Humeral shaft injuries

Cite this article as:
PJ Whooley. Humeral shaft injuries, Don't Forget the Bubbles, 2021. Available at:
https://doi.org/10.31440/DFTB.29682

Six-year-old Rosie was running in from the back yard when she just tripped over the skateboard that her mum had told her to tidy up. She landed directly onto her left arm. She was brought to the ED and it was noted she was unable to extend her left wrist and she had pins and needles over the back of her hand. 

Humeral shaft fractures are uncommon, accounting for less than 10% of paediatric fractures. Children have a great ability to remodel and heal with little or no deformity despite significant displacement and angulation therefore most of these fractures can be managed with simple immobilization. 

Anatomy

The thick periosteal sleeve of the humerus limits the displacement of humeral fractures and promotes excellent healing. The main anatomical feature that is important to remember is the radial nerve, which curves around the back of the mid humerus and is at risk of injury. That said, injuries of the radial nerve secondary to humeral fractures are rarely associated with long-term deficits with the majority being temporary neuropraxia.

Mechanism of injury

Neonates – hyper extension or rotation as they pass through the birth canal. The typical fracture is a transverse midshaft fracture. 

Older children – Fall on an outstretched hand (FOOSH), a direct blow to the upper arm or high energy trauma such as a motor vehicle collision. 

Adapted from Orthobullets.com 

Pathological fracture – suggested when a midshaft humeral fracture occurs after only minimal trauma. The humerus is a common site for bone cysts and other benign lesions. These occur most commonly in children 3-12 years of age. 

Case courtesy of Dr. Hani Makky Al-Salam, Radiopaedia.org. From the case rID: 13537

Non accidental injury – Is the mechanism inconsistent with the injury or is there a fracture in a healthy child younger than 3 years? This should raise concern for child abuse. These fractures can be transverse fractures from a direct blow or an oblique or spiral fracture caused by traction with humeral twisting. 

Evaluation

These injuries often present with mid arm pain and swelling. If a humeral fracture is present with no visible deformity, it is typically minimally displaced. 

Determine if there is any distal neurovascular compromise (check out the elbow examination post for some top tips on neurovascular assessment in upper limb injuries). Vascular injuries are extremely rare but midshaft fractures are associated with radial nerve injuries in 5% of fractures. This will be evident with paraesthesia / numbness in the dorsum of the hand between the 1st and 2nd metacarpal and motor deficit with reduced thumb and wrist extension and reduced forearm supination. 

Radiology

Typical Anterior-posterior (AP) and lateral views are sufficient. A prominent vascular groove in the distal humerus is commonly seen on plain film and should not be confused with a fracture line. 

Case courtesy of Kellie Grant, Radiopaedia.org. From the case rID: 39526

Describing humeral fractures

There are four key descriptors of humeral fractures:

  1. Anatomical location: proximal, middle or distal third
  2. Fracture pattern: spiral, short oblique, transverse or comminuted
  3. Degree of displacement and angulation
  4. Presence of soft tissue damage: is the fracture open or closed?

Analgesia and immobilisation

Give early analgesia. These are sore and children often require opiate analgesia such as intranasal fentanyl or diamorphine, which are safe to give if there is no facial trauma or signs of head injury present. 

Immobilization in a sling and swathe or shoulder immobilizer enhances patient comfort and reduces the chance of further fracture displacement. Be sure to check for and document any neurovascular deficit pre and post immobilization.

Infants – sling and a swathe for 4 weeks is sufficient regardless of the degree of displacement.

Older children – In incomplete fractures then a sling and swathe, a collar and cuff sling or a shoulder immobiliser can be used. 

Complete and moderately displaced fractures are better managed in a hanging U-slab. This uses gravity to decrease the deformity by relaxing the muscles and also improves the child’s comfort. Provided there is no radial nerve injury, the fracture can be reduced under procedural sedation to improve clinical alignment. After reduction, the child is placed in a U-slab or coaptation splint for 2 weeks. In the fracture clinic, they will then be reassessed and braced in a functional clamshell brace until approximately 4 weeks.

Hanging U-slab

Refer for orthopaedic assessment in ED if there are any of the following features present:

  • Compound fracture with neurovascular compromise
  • Open fracture
  • 100% displacement
  • Fracture with clinical deformity 
  • Angulation more than 20° in children and 10° in adolescents
  • Compartment syndrome (rare in midshaft humeral fractures)

Operative management involves open reduction and internal fixation. It is indicated in many of the above but also the multiply injured patient to aid in early ambulation including concomitant forearm fractures resulting in a “floating elbow”.  

‘Floating elbow’ in a child with concomitant humeral and forearm fractures. Image from Orthobullets.com

Outcomes

  • Malunion is common, but there’s usually little functional loss. These remodel well.
  • Initial fracture shortening may be compensated for by later overgrowth
  • Nonunion is uncommon
  • Radial nerve palsy is less common, and when occurs, is usually a temporary neuropraxia

Rosie was brought to theatre for an open reduction of her left midshaft humerus fracture. The radial nerve was trapped in the fracture line but not severed. After a few weeks of physio Rosie has regained full movement of her wrist and hand and she loves the fact that she has a scar on her arm. Skateboards have been banned from the house…

References

  1. JC. Cheng, JY. Shen. Limb fracture pattern in different pediatric age groups: a study of 3,350 children. J Orthop Trauma. 1993;7(1):15
  2. S. Carson, DP. Woolridge, J. Colletti, K. Kilgore, Pediatric upper extremity injuries. Pediatr Clin North Am. 2006 Feb;53(1):41-67, v.
  3. Figure 3 – Case courtesy of Dr Hani Salam, <ahref=”https://radiopaedia.org/”>Radiopaedia.org</a>. From the case <ahref=”https://radiopaedia.org/cases/13537″>rID: 13537</a>
  4. https://emedicine.medscape.com/article/1231103-overview
  5. https://www.rch.org.au/clinicalguide/guideline_index/fractures/Humeral_shaft_fractures_Emergency_Department/

Midshaft radius and ulna fractures

Cite this article as:
Rie Yoshida. Midshaft radius and ulna fractures, Don't Forget the Bubbles, 2021. Available at:
https://doi.org/10.31440/DFTB.21902

Alvaro is a 12-year-old boy who presents to the ED with a painful and swollen right arm. He was trying out his new skateboard and fell whilst trying to master the kickflip. (He tells you it’s not cool to say he’s been skateboarding: “It’s skating, but not the on-ice kind, that’s not cool either.”)

On examination, he is tender in the middle third of his right forearm with swelling and some mild deformity.  There are no open wounds. There is pain on forearm rotation with limited pronation and supination but a good range of movement at the wrist and elbow.  There are no signs of neurovascular compromise or compartment syndrome. 

You top him up with some intranasal fentanyl and send him for an x-ray. His AP film shows a greenstick in the middle third of the ulna. 

Case courtesy of Dr. Jeremy Jones, Radiopaedia.org. From the case rID: 66836

But when you look at his lateral you do a double-take. There’s pretty significant angulation with radial bowing. You always make sure you look at both x-ray views but this really shows why that’s so important.

Case courtesy of Dr. Jeremy Jones, Radiopaedia.org. From the case rID: 66836

You know that ulna fractures can be associated with radial head dislocations as part of the Monteggia fracture-dislocation pattern so send Alvaro back for an elbow x-ray.  Radio-capitellar alignment is maintained so you’re happy this isn’t a Monteggia injury but given the significant ulna angulation, you give your orthopaedic on-call colleague a ring.

 

Epidemiology

Forearm fractures are the most common fractures in children, representing 40% of all childhood fractures. Although the majority of these occur at the distal end of the forearm, 20% are located at the midshaft and often involve both bones.  Peak incidence occurs between ages 10-14.

 

Anatomy

The radius and ulna are connected by an interosseous membrane and meet at the distal and proximal radioulnar joints at the wrist and elbow.  Due to these connections, a break in one bone is often accompanied by a break in the other.  It is also important to look at the proximal and distal radioulnar joints to identify Monteggia and Galeazzi fracture-dislocations.

Mechanism

Midshaft radius and ulna fractures usually occur due to a fall from a height onto the forearm or an outstretched hand or direct blow to the forearm.

 

Examination findings

Examine the forearm, wrist and elbow joint.  You may find swelling and possible deformity with tenderness of the forearm. Check for any open wounds and check the tetanus status of the child.

The range of movement will be reduced, particularly with forearm pronation and supination. Check for signs of neurovascular compromise or compartment syndrome.

 

Investigations

For all midshaft forearm injuries, order true AP and lateral x-rays of the forearm including the wrist and elbow (including distal humerus). Note: 5% of forearm fractures are associated with supracondylar fractures.

In a true AP x-ray, the distal radius (R) and ulna (U) should be visualized with minimal overlap. The trochlea (T) and capitellum (C) should be seen in profile, as long as the child is old enough for them to have both to have ossified.

In a true lateral, the distal radius (R) and ulna (U) will be superimposed at the wrist.  If there is no plastic deformity the posterior border of the ulna is straight, sitting on an imaginary horizontal line, and the radius is bowed. The trochlea and capitellum will be superimposed at the elbow (denoted by *).

True AP: Case courtesy of Dr. Aditya Shetty, Radiopedia.org, rID:31106 True lateral: Case courtesy of Dr. James Hayes and Dr. Aditya Shetty, Radiopedia.org, rID:31107

 

Classification

The Rule of Fours can be used to describe the fracture and identify the correct fracture pattern.

There are 4 types of fracture patterns:

  • Plastic deformation: there is bowing of the bone with no cortex disruption. It’s most commonly seen in the ulna and is easily missed on x-ray. A top tip for spotting on x-ray: on the lateral view, a normal ulna has a straight posterior border.  But if the posterior border does not sit nicely on a horizontal line there is plastic deformation.

  • Greenstick fractures: there is a break on one side of one bone that does not extend all the way through the bone.
  • Complete fractures: there is a fracture through both cortices of the radius and/or ulna, often with displacement.
  • Comminuted fractures: these are fractures with multiple bony fragments. They are uncommon in midshaft fractures in children.

 

Treatment

The vast majority of paediatric forearm fractures can be managed non-operatively, with closed reduction and casting.

Firstly, check whether the fracture needs to be referred to the orthopaedic team. Any fracture with complications, either a plastic, comminuted or open fracture or one with neurovascular compromise, compartment syndrome or associated Monteggia or Galeazzi dislocation, must be referred to the on-call orthopaedic clinician.

Next, assess the degree of angulation. If the child is under 5 years of age, up to 20 degrees angulation is acceptable; aged 5 – 9 up to 15 degrees is allowable; and in children 10 years and older fractures with angulation of up to 10 degrees will remodel without manipulation. Fractures that are more angulated than this will need to be reduced.

Closed reduction should be performed by an experienced ED practitioner or clinician or by the orthopaedic team.  It may be done either under procedural sedation in the ED or in theatre with image intensification if this fails (or if the fracture is complicated).  Always, always, reassess neurovascular status and repeat an x-ray after manipulation to reassess the degree of angulation and ensure no further complication has arisen. And finally, an above-elbow (long arm) cast should be applied with follow-up in fracture clinic within a week.

 

Indications for orthopaedic referral

  • Open fracture
  • Neurovascular compromise
  • Compartment syndrome
  • Comminuted fracture
  • Monteggia or Galeazzi fracture
  • Failed reduction or unable to perform in the ED

 

Top tips

  • Always check both lateral and AP films. Alignment can look deceptively good in one plain and very angulated in another.
  • If a break in one forearm bone is identified, remember to look at the other bone and the radioulnar joints. Don’t forget forearm fractures are associated with supracondylar fractures and can be complicated by Monteggia or Galeazzi fracture-dislocations.

 

Alvaro’s ulna greenstick fracture had over 10 degrees of angulation and you and your orthopaedic colleague agree a closed reduction in ED is called for.  You manage Alvaro’s procedural sedation while the orthopaedic doctor re-moulds the fracture and places Alvaro in an above elbow backslab.  Post-reduction films show good alignment.  A few months later you’re walking past the local skate park and you smile to yourself as you see Alvaro with his skateboard (correction, on his board). He gives you a grin as he spins into a kickflip.

 

Selected References

Vopat, Matthew L et al. “Treatment of diaphyseal forearm fractures in children.” Orthopedic reviews vol. 6,2 5325. 24 Jun. 2014, doi:10.4081/or.2014.5325

Orthobullets Both Bone Forearm Fracture – Pediatric https://www.orthobullets.com/pediatrics/4126/both-bone-forearm-fracture–pediatric

Schweich P. Midshaft forearm fractures in children. Post TW (Ed). UpToDate, Waltham, MA. 2019.

Price CT. Acceptable alignment of forearm fractures in children: Open reduction indications. J Pediat Ortho 2010; 30: S82-4.

Clavicle fractures

Cite this article as:
PJ Whooley. Clavicle fractures, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.29144

Darragh is a 7 year old who needed to get his ball back from his neighbour. He decided to jump the tall fence but fell before he got over the top and landed on his right shoulder. Mum brings him in and he is holding right arm to his side and not happy when you try and examine his shoulder. The ED doctor has ordered an x-ray.

Epidemiology

Clavicular fractures are the most common shoulder fracture in children (8% to 15% of all paediatric fractures). They are common during delivery too and occur in 0.5% of all normal and 1.6% of breech deliveries, accounting for 90% of obstetric fractures.

Anatomy

80% of clavicular growth occurs at the medial epiphysis. It ossifies between 12-19 years of age and fuses fully by 22-25 years. The clavicle is the first bone in the body to ossify (intrauterine week 5), but the medial clavicular epiphysis is the last to appear and close. There are multiple ligamentous connections that are relevant.

Mechanism of injury

There are two mechanisms of injury: indirect and direct.

Indirect injuries commonly occur after a fall onto an outstretched hand (FOOSH).

Direct fractures are sustained from direct trauma to the clavicle or acromion and are associated with a higher incidence of injury to underlying neurovascular and pulmonary structures.

Evaluation

Children typically present with a painful, palpable and tender mass. There is usually a discrete tender swelling, but tenderness may be diffuse in the cases of a plastic bowing. Bony crepitus and ecchymosis are often present. It is important to ensure there is no overlying skin compromise.

Assess neurovascular status as although brachial plexus and subclavian artery injuries are rare, they can occur and will require urgent orthopaedic intervention.

In the setting of direct trauma, assess the child’s respiratory status. Rarely medial clavicular fractures may be associated with tracheal compression in the setting of significant posterior displacement.

Radiology

Clavicle plain films are often sufficient rather than full shoulder x-rays. Often a single view might be all that is obtained. The diagnosis may be made as an incidental finding on other x-rays such as a chest x-ray. In the trauma setting, 2 views are ideally better than one: a frontal view and a cephalic tilt (15-45 degree).

In most cases, clavicle fractures are easily identified on plain x-ray. There is commonly displacement of the fracture; the medial fragment is pulled upwards by the sternocleidomastoid while the distal fragment is pulled downwards by the weight of the arm. Occult fractures may also be present. When describing a clavicle fractures note the location of the fracture along the shaft. The Allman Classification of clavicle fractures separates the segments into thirds.

Look for angulation and/or displacement of the fracture. Is it comminuted?  If there is shortening, measure, and document the degree of overlap (> or < 2cm), sometimes best seen on a PA chest x-ray.

Note any relevant negatives and associated findings. Comment on any variation in sternoclavicular (SC) joint, acromioclavicular (AC) and coracoclavicular (CC) alignment and distances.

Normal acromio-clavicular alignment

Midshaft clavicular fractures

Midshaft clavicular fractures are the most common paediatric shoulder fractures, accounting for 10-15% of all fractures. Half of these are in children <10 years. They almost always heal but if they don’t, the malunion is usually not of clinical significance. There is excellent remodeling within one year and complications are very uncommon. Thankfully, like many other children’s fractures, they commonly fracture in a greenstick pattern.

Operative management is reserved for adults and children over the age of 10 years, particularly if the clavicle is significantly shortened or displaced.

Case courtesy of Dr Ian Bickle, Radiopaedia.org. From the case rID: 53795

Neer classification of midshaft fractures

  • Non-displaced: If there is less than 100% displacement, these are managed conservatively
  • Displaced: If there is greater than 100% displacement, the non-union rate is 4.5%. These are managed operatively.

Medial Clavicular Injuries

Medial clavicular injuries are much less common in children. Most medial clavicular injuries are Salter-Harris type I or II.

True sternoclavicular (SC) joint dislocations, though rare, may occur and in the case of posterior dislocations, 30% are associated with life-threatening mediastinal injuries.

I’ll take a minute to describe this as it’s an important point. In SC joint dislocations, the clavicle typically displaces anteriorly in up to 90% of cases.

If concerned, then x-raying both sides (called a serendipity view) would help make a diagnosis.  If there remains concern, then a CT scan of the SC joint can be helpful, and is generally favoured as the imaging modality of choice.

Clinical image showing a protrusion over the right SCJ. Corresponding AP plain film demonstrating widening of the SCJ. From brownemblog.com

Most children with an anterior SC joint dislocation can be managed with a sling or collar and cuff.

Much less often the clavicle moves posteriorly in relation to the sternum, especially in the setting of tremendous force applied to the shoulder or the medial clavicle. If there is no evidence of medial epiphyseal fracture but pain and swelling is present you must consider a dislocation. Posterior dislocations can present with pain over the anterior chest, increased on shoulder movement. A dislocation may impact the structures behind including the trachea and blood vessels in that region. Hoarseness could indicate a recurrent laryngeal nerve injury or airway compromise.

SC joint dislocations are classified as Grades I-V, with Grade V being a posterior dislocation. Any child with a suspected posterior SC joint dislocations should be referred to the on-call orthopaedic team – these are orthopaedic emergencies, with CT angiograms favoured to characterise the extent of vascular injury and operative reduction performed, often in consultation with vascular surgeons.

Lateral third clavicle fractures

These can be easily confused with acromioclavicular (AC) joint injuries. Both present clinically with pain and tenderness around the AC joint plus swelling and bruising. The ‘cross-arm test’ (ABDuction across the chest) results in increased pain in both conditions. Little or no deformity may be seen on x-ray unless a Salter-Harris II fracture is present.

Management

Nonoperative management involves sling immobilisation with gentle range of motion exercise at 2-4 weeks and strengthening at 6-10 weeks. This is indicated in fractures of the middle 1/3, if there is shortening and displacement that is under 2cm with no neurology.

Operative management, open reduction and internal fixation (ORIF), is indicated in open fractures, displaced fractures with skin compromise and/or subclavian artery or vein injury and in major trauma with a floating shoulder where the clavicle and scapular neck are both fractured.

Complications

Non-union can occur in up to 5% of all types of clavicular fractures. Clavicular injuries that are most at risk of non-union include comminuted fractures and 100% displaced fractures with shortening that is over 2cm, resulting in decreased shoulder strength and endurance. Children over the age of 10 with displaced clavicular fractures will often have a face to face consultation in fracture clinic to discuss operative options to optimize outcome.

Who doesn’t need follow-up?

Children under 10 with an undisplaced fracture don’t need follow-up (although some places offer virtual follow-up), with simple management with a broad arm sling for 2 weeks and no contact sports for another 6 weeks after the sling is removed. It’s important to tell the child’s parents that a lump will form at the fracture site and will last for about a year. Give safety netting advice to return if they develop any sensory changes.

Thankfully Darragh only suffered a midclavicular greenstick fracture with minimal angulation. His arm was placed in a broad arm sling and his parents were told to keep it on for 2 weeks and no fence vaulting for a couple of months! As Darragh’s only 7 years old and his fracture was not significantly displaced, his parents were reassured that it would heal nicely. Most importantly he eventually got his ball back. Phew!

References

JS. Zember, ZS Rosenberg, S. Kwong, SP. Kothary, MA. Bedoya. Normal Skeletal Maturation and Imaging Pitfalls in the Pediatric Shoulder.  Radiographics. 2015 Jul-Aug;35(4):1108-22

https://radiopaedia.org/articles/paediatric-shoulder-radiograph-an-approach

Acromio-clavicular joint injuries

Cite this article as:
PJ Whooley. Acromio-clavicular joint injuries, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.29623

John went in for the ball but was tackled off it and ended up falling onto his shoulder to the ground. He was able to finish the game but had a lot of pain when he stretched his arm across the front of his chest.

AC joint anatomy

The acromioclavicular (AC) joint combines the distal clavicle and the acromion (the superolateral part of the scapula). The joint is supported by a ligament complex as well as the surrounding fascia and muscles. The main ligaments involved are the acromioclavicular ligaments and the coracoclavicular (CC) ligament. The CC ligament is made up of the lateral trapezoid ligament and the medial conoid ligament. 

Mechanism of injury

Injury to the AC joint means disruption of the AC ligaments with or without disruption of the CC ligament. It occurs in up to 10% shoulder girdle injuries and is more common in athletes. Injury typically occurs from a direct blow or following a fall onto the superior or lateral part of the shoulder with the arm adducted. This results in the acromion being forced inferiorly and medially to the clavicle. Injury with a low force causes an AC sprain, with progressively increased force causing AC ligament rupture and then additional sprain and rupture of the CC ligaments. 

Examination 

AC joint injury presents with pain and tenderness over a possibly swollen AC joint. The pain may also be referred to the trapezius muscle. When compared to the contralateral side there may be an abnormal contour. 

If the diagnosis is in doubt you can perform the crossbody ADDuction (Scarf test) to compress the AC Joint. If this is painful, this is suggests AC joint injury. A careful distal neurovascular exam of the involved extremity shoulder be performed, documenting radial, ulnar and median nerve function (take a look at the examining paediatric elbow post for top tips on conducting a proper neurovascular assessment in upper limb injuries).

Young boy trying to hurt his sister (and failing)

It is important to rule out atraumatic distal clavicle osteolysis, a repetitive stress injury in young athletes who do high level upper weight training.

AC injury infographic

Radiology

There are two approaches to plain film imaging in suspected AC joint injury:

  • a single AP view including both AC joints 
  • one AP view of each shoulder comparing affected with the unaffected side

This image from Orthobullets.com shows AC joint widening on the left compared to a normal AC joint on the right.

If there is still some doubt the AC joints can be better seen on Zanca views using a 10-15 degrees of cephalic tilt. Stress views are often used with weights in each hand to determine AC joint instability. This is important also to out-rule coracoid fractures often seen in stress overuse as in young athletes who do repetitive weight training.

Zanca views of the left shoulder. In these images, the ACJ has not become widened on weight-bearing indicating a normal AC joint, with no injury. Case courtesy of Dr Henry Knipe, Radiopaedia.org. From the case rID: 68155

Look carefully at the clavicle for any associated occult clavicle fractures.

Classification

Paediatric AC joint injuries are classified as grades I – VI by the Rockwood classification

In the ED, the most common injuries, occurring after minor trauma, are types I to III, ranging from stretching of the AC ligament to complete tear with clavicle lifting: 

  • I – AC ligament sprain with intact periosteal sleeve
  • II – Partial periosteal sleeve disruption with AC Joint widening (CC distance <25% contralateral side)
  • III – Disrupted periosteal sleeve with superior (upwards) displacement of the clavicle, with between 25 – 100% displacement

Types IV to VI typically occur after high energy trauma and need surgical intervention:

  • IV – Distal clavicle displaced posteriorly through the trapezius
  • V – Deltoid and trapezius detachment and clavicle displacement >100%
  • VI – Clavicle displaced inferiorly under the coracoid

Management

Rockwood Grades I – III AC joint injuries: Non-operative management is the mainstay as these are low energy injuries. Analgesia, ice and rest in a sling or figure-of-eight braces followed by gentle range of motion exercise once the pain has settled. Early rehabilitation with cautious exercise results in earlier return of normal shoulder range of motion, with functional motion by 6 weeks and normal activity by 12 weeks. The lower the grade the earlier the return to normal function. Caution needs to be taken to avoid manoeuvres that that strain the ligaments and cause pain. Avoid cross-body ADDuction, extreme internal rotation (i.e. behind the back) and overhead movements.

Rockwood Grades IV to VI injuries: Operative management is indicated in grades IV to VI but also in Grade III that have failed non operative treatment or in elite athletes and for cosmesis.

Complications

Up to 30 – 50% of patients with AC joint injuries complain of residual pain. 

John thankfully only had a Grade II AC joint injury and wore a shoulder immobilizer for 3 weeks. He’s already back training but is a little more cautious when he goes in for the tackle. 

References

AD. Mazzocca, RA. Arciero, J. Bicos. Evaluation and treatment of acromioclavicular joint injuries. Am J Sports Med 2007;35:316-329.

JD. Gorbaty, JE Hsu. AO. Gee.  Classifications in Brief: Rockwood Classification of Acromioclavicular Joint Separations. Clin Orthop Relat Res. 2017 Jan; 475(1): 283–

S. Evrim. N. Aydin, OM. Topkar. Acromioclavicular joint injuries: diagnosis, classification and ligamentoplasty procedures. EFORT Open Rev 2018;3:426-433

Talk ortho like a pro

Talk ortho like a pro

Cite this article as:
Orla Callender. Talk ortho like a pro, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.30463

Clear and structured communication between the emergency and orthopaedic team is paramount to ensuring a smooth transfer of care for children with fractures and traumatic injuries. Use this checklist to structure your referrals to ortho like a pro, and test your x-ray interpretation skills with the quiz below.

History

Injury is force meets child; child is damaged. Force causes an easy-to-remember event – shock, pain, ‘crack’, blood, fear – so there will always be a history of an injury. When taking a history, remember the six honest men: when, how, where, what, who and why.

In addition to a full history of presenting complaint and past medical, vaccination and developmental history, a trauma history should include:

  • Date and time of injury
  • Exact mechanism of injury when possible, preferably in parent’s or child’s own words
  • Environment in which the injury occurred
  • Symptoms at time of injury and subsequently
  • Hand dominance for upper limb injury
  • Analgesia administered
  • Fasting status
  • Relevant past medical history such as bleeding disorders

Sadly, we must always remain vigilant for signs of non-accidental injury (NAI). The presenting injury needs to reasonably fit with the account as to the mechanism of injury.

Examination

Whilst the majority of the examination of a traumatic injury is centred on the affected site, the examination must always include:

The examination should be broken down into:

  • Inspection
  • Palpation
  • Movements and gait
  • Neurovascular status
  • Special tests

Imaging

Fractures can generally be identified on an AP and lateral radiograph. Use a systematic approach and apply the rule of two’s.

Apply rule of two’s:

  • Two views as standard; occasionally other views may be required
  • Two joints viewed
  • Two sides where comparison of normal is necessary
  • Two occasions before and after procedures or in specific instances (such as when a scaphoid fracture is suspected)

A fracture may appear as a lucency (black line) where a fracture results in separation of bone fragments or as a dense (white) line where fragments overlap. If bone fragments are impacted, then increased density occurs which may be the only radiological evidence that a fracture exists.

Sometimes, there is no direct evidence of a fracture and instead, we need to rely on indirect evidence. Looking for radiological soft tissue signs can provide clues to fractures. These include displacement of the elbow fat pads or the presence of a fluid level.

The AABCS approach, described by Touquet in 1995, can be used to carry out a structured interpretation of a limb x-ray.

Key points:
•   Examine the entire radiograph in detail before concentrating on the area of concern – Look at the whole x-ray and the x-ray as a whole
•   Remind yourself of mechanism of injury – Are the radiographic findings relevant to patient history? How do the findings correlate with clinical findings? Do you need to re-examine the patient?
•   Take an x-ray before and after procedures
•   Get help – If the x-ray doesn’t look right ask someone else, and ensure there is a backup reporting system in place
•   Document both what you see and what you don’t see on the x-ray

Describing fractures

Fractures are described systematically. Start with the site (name and part/portion of bone), then extent (fracture type/line, open/closed, articular involvement), then describe the distal fragment (displacement and angulation). Describe any involvement of the skin and damage to related tendons and structures such as nerves or blood vessels.

Describing the site

Long bones are often described based on thirds: proximal, middle (diaphyseal) and distal segment. Including nearby anatomical landmarks (head, neck, body /shaft, base, condyle, epicondyle, trochanter, tuberosity etc.) helps describe the area of interest.

In paediatrics, fractures are described including the anatomical divisions of the bone segments: the epiphysis, the epiphyseal plate, the metaphysis and the diaphysis.

  • The diaphysis is the shaft of the bone
  • The physis is the growth plate. Also known as the epiphyseal plate, the physis occurs only in skeletally immature patients and is a hyaline cartilage plate in the metaphysis, at the end of a long bone.
  • The metaphysis lies between the diaphysis and the physis. An easy way to remember this is to think of the word metamorphosis – a change; the metaphysis is the area of change between the physis – the growth plate – and the diaphysis – the shaft. The metaphysis is only used to describe a bone before it matures – it is the growing end of the long bone. Metaphyseal fractures are almost pathognomonic of NAI. They are also known as corner fractures, bucket handle fractures or metaphyseal lesions
  • The epiphysis sits above the growth plate – epi (Greek for over or upon – like the epidermis) – physis – upon the physis

Describing the extent

For revision of specific terms to use to describe the type of fracture, see the fracture terminology glossary below. Key characteristics to add include whether the fracture is open or closed, and whether the fracture is intra-articular (inside the joint capsule) or extra-articular. Extra-articular fractures are usually less complicated.

Describing the distal fragment

There is a convention to ensure that the same injury is described in the same way: angulation, displacement, and dislocation are described by where the distal fracture fragment is in relation to the proximal fragment, or in the direction of the fracture apex.

Displacement is the loss of axial alignment: dorsal (posterior), volar (anterior) or lateral displacement of the distal fragment with respect to the proximal fragment. The degree of displacement can be roughly estimated from the percentage of the fracture surfaces in contact. Where none of the fracture surfaces are in contact, the fracture is described as having ‘no bony opposition’ or being ‘completely off-ended’, and are potentially unstable. Displacement is usually accompanied by some degree of angulation, rotation or change in bone length.

Angulation is the angle created between the distal fragment and the proximal fragment as a result of the fracture. The anatomical reference point is the long axis. Angulation is described using words like: dorsal / palmar; varus / valgus; radial /ulnar. It may be described either by reference to the direction in which the apex of the fracture points (apex volar or apex dorsal) or by indicating the direction of the tilt of the distal fragment. Medial angulation can be termed ‘varus’, and lateral angulation can be termed ‘valgus’. To measure angulation, one line is drawn through the midline of the shaft. A second line is then drawn through the midline of the fragment and the angle can now be measured.

Rotation is present when a fracture fragment has rotated on its long axis relative to the other. It may be with or without accompanying displacement or angulation. It is more readily diagnosed on clinical examination.

Finally, perfecting your referral

Referrals to the orthopaedic team, using a framework like the ISBAR tool, should start with the child’s name, hospital number and who is attending with the patient. Then proceed to give a history, including a full history of the presentation, hand dominance, fasting status and any relevant clinical risk factors such as bleeding disorders. Describe your clinical findings, including neurovascular examination, and then the radiological findings in the order of:

  • the bone(s) involved
  • part of bone
  • type of fracture
  • fracture line
  • extent of deformity and angulation
  • and any associated clinical findings

Describe any other investigations, management to date and on-going treatment. Summarise events that have occurred before referral – analgesia, backslab casts, splints, antibiotics, tetanus boosters, wound cleansing, dressings etc.

As with any good referral, be clear about why the child is being referred. It may be reasonable to transfer full care of a child. Or, the referral may simply be to gain a second opinion on the diagnosis followed by management. Be clear about the type of care expected. And finally, discuss whether you feel the referral is urgent or not. It should be stated how quickly you expect the patient to be seen. Do you feel they need to be seen urgently, soon or routinely?

At this stage, a management plan and expected outcome can be discussed and agreed. This information can then be reiterated to the child and family. Make sure everything is clearly and concisely documented.

Done!

Fracture terminology

Non-displaced fracture: A fracture where the pieces of the bone line-up.

Displaced fracture: The pieces of the bone are out of line.

Closed fracture: Either the skin is intact or, if there are wounds, these are superficial or unrelated to the fracture.

Open / compound fracture: A wound is in continuity with the fracture site.

Unstable fracture: A fracture with a tendency to displace after reduction.

Complete fracture: The fracture line extends across the bone from one cortex to the other separating the bone into two complete and separate fragments.

Greenstick fracture: Only one cortex is fractured.

Torus / buckle: Buckling of the cortex with no break.

Comminuted: There are more than two fragments.

Transverse fracture: A fracture across the bone.

Oblique fracture: A fracture at an angle to the length of the bone.

Spiral fracture: A fracture that curves around the bone diameter.

Depressed: A portion of bone is forced below the level of the surrounding bone.

Avulsion fracture: The muscle have torn off the portion of bone to which is attached.

Stress fracture: Tiny cracks in the bone caused by repetitive injuries. A cortical break is not always seen but there is greying of the cortex due to callus formation.

Pathological fracture: A fracture arising within abnormal bone weakened by benign or malignant cysts or tumours.

Impacted fractures: One fracture fragment is driven into the other.

Plastic deformation: Deformation of bone without fracture of the cortex.

Epiphyseal fractures: A fracture to the growing end of a juvenile bone that involves the growth plate. Use the Salter-Harris classification if the fracture involves the epiphyseal plate.

Fractures don’t always occur in isolation – a joint may be involved.

Fracture-dislocation: A dislocation is complicated by a fracture of one of the bony components of the joint, such as a Galeazzi or Monteggia fracture-dislocation.

Subluxation: The articulating surfaces of a joint are no longer congruous, but loss of contact is not complete.

Dislocation: Complete loss of contact between the articulating surface of a joint. Displacement of one or more bones at a joint.

References

Bickley S. & Szilagyi P. (2003) Bates’ Guide to Physical Examination and History Taking (8th edn.) Philadelphia. J.B. Lippincott, Philadelphia.

Davis, F.C.W., 2003. Minor Trauma in Children. A pocket guide. London: Arnold.

Duderstadt, K. 2006. Pediatric Physical Examination. Mosby. Elsevier.

Purcell, D. 2003. Minor Injuries. A Clinical Guide. Edinburgh: Churchill Livingstone.

Larsen, D. & Morris, P. 2006. Limb X-ray Interpretation. Whurr Publishers Limited.

McRae, R. 2003. Pocketbook of Orthopaedics and Fractures. 3rd ed. Edinburgh: Churchill Livingstone.

Raby, N., Berman, L. & De Lacey, G., 2001. Accident & Emergency Radiology. A Survival Guide. Edinburgh: W.B. Saunders.

Touquet et al, 1995. The 10 Commandments of Accident and Emergency Radiology. BMJ 1995; 311: 571.

Image source for final quiz case: https://radiopaedia.org/cases/2c1840c5145638e56f599031f23dd0c8?lang=us

Wrist x-rays

Cite this article as:
Sian Edwards. Wrist x-rays, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.29082

The wrist is one of the most commonly requested X-Rays in the children’s emergency department. Wrist views are requested when injury to the distal radius/ulna or carpal bones are suspected. Below is a systematic approach to interpretation.

The wrist series examines the carpal bones (scaphoid, lunate, triquetrum, pisiform, trapezium, trapezoid, capitate and hamate), the radiocarpal joint and the distal radius and ulna. 

There are eight carpal bones present and each one is named according to its shape:

  1. Scaphoid (boat-shaped)
  2. Lunate (crescent moon-shaped)
  3. Triquetrum (pyramidal)
  4. Pisiform (pea-shaped)
  5. Trapezium (irregular trapezium-shaped)
  6. Trapezoid (wedge-shaped)
  7. Capitate (head-shaped) – *the largest of the carpal bones
  8. Hamate (wedge-shaped with a bony extension, or ‘hook’)
Labelled XR of carpus
AP
Proximal carpal rowDistal carpal row
ScaphoidTrapezium
LunateTrapezoid
TriquetrumCapitate
PisiformHamate

How to best remember the carpal bones

There are many mnemonics around – some too rude for mention here! You will need to find the one that works for you… here’s one that’s super suited for clinicians working with kids:

Sam Likes To Push The Toy Car Hard

Failing that, save an image to your phone for quick reference!

Mnemonic for remembering carpal bones

Ossification

The carpal bones are formed entirely from cartilage at birth – this is important from a radiological viewpoint as it means they are not visible on x-ray initially. They begin to ossify from about 1-2 months of age and are fully developed by the age of 8-12 years. Although there is variability in the timing, the order is always the same.

  1. Capitate 1-3 months
  2. Hamate 2-4 months
  3. Triquetrum 2-3 years
  4. Lunate 2-4 years
  5. Scaphoid 4-6 years
  6. Trapezium 4-6 years
  7. Trapezoid 4-6 years
  8. Pisiform – 8-12 years

Generally, on x-ray, one carpal bone is visible every year until full development – this acts as a handy (pun intended) ageing tool!

On requesting wrist X-Rays, most commonly you will receive posteroanterior and lateral projections, with oblique views forming part of the series usually when carpal injury is suspected.

1. Check the soft tissues

Look for signs of swelling or any incidental findings.

2. Trace the bony cortices

Trace each bone in turn to look for breaks or irregularities in the cortex.

Look closely at the distal radius, proximal carpal row (especially the scaphoid) and the proximal metacarpals. Disruptions in the cortex may be very subtle as in the case of this torus fracture (aka a buckle fracture)

Buckle fracture of radius
Buckle fracture

3. Check bony alignment

On the AP view:

The distal radial articular surface should curve round the carpals with the articular surface getting more distal towards the ulnar styloid. The articular surfaces of the proximal and distal carpal rows should form three smooth arcs – these can be traced on the AP film.

The spacing between all carpal bones should be 1-2mm.

If the arc is broken or there is widening or lack of uniformity between the spaces, think about carpal dislocation.

The articular cortex at the base of each metacarpal parallels the articular surface of the adjacent carpal bone.

The carpo-metacarpo (CMC) joint spaces should be clearly seen and of uniform width (1-2mm).

The 2nd to 5th CMC joints are visualised as a zigzag tram line – on a normal view, there will always be the “light of day” seen between the bases of the 4th and 5th metacarpals and the hamate bone. If this is narrowed, think dislocation of the 4th or 5th metacarpal.

Labelled AP view of wrist
AP view

On the lateral view:

The distal radius, lunate and capitate should articulate with each other in a straight line on the lateral x-ray – the apple, cup, saucer analogy – the cup of the lunate should never be empty.

Lateral view of carpus
Normal capitate – lunate – radius alignment. Image adapted from a case courtesy of Dr Jeremy Jones, Radiopaedia.org. From the case rID: 37947

If the cup is empty, this suggests a perilunate dislocation.

Perilunate dislocation
Perilunate dislocation. Image adapted from a case courtesy of Dr Ian Bickle, Radiopaedia.org. From the case rID: 46714
The apple and cup model of perilunate dislocation
The slipped cup of the perilunate dislocation

References

https://radiopaedia.org/articles/wrist-radiograph-an-approach?lang=gb

Galeazzi fracture-dislocations

Cite this article as:
Rie Yoshida. Galeazzi fracture-dislocations, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.21150

Patrick is a 15-year-old boy who presents to the Emergency Department with a painful left arm.  He tells you he fell off his bicycle, putting out his left hand out to break the fall.  On examination, his left forearm is deformed at the wrist.  There are no open wounds and no signs of compartment syndrome. The limb is neurovascularly intact.  

He has declined analgesia in triage but you convince him to take paracetamol and ibuprofen prior to his x-ray. You order a lateral and AP film of his left forearm including the wrist and elbow.  

Th. Zimmermann [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0)]
His x-ray shows a distal radial fracture.  Whilst you are assessing the degree of angulation, a medical student leans over your shoulder and asks, ‘Should the head of the ulnar be sticking out like that?’. You nearly missed it but Patrick has a rare Galeazzi fracture-dislocation! 

Galeazzi fracture-dislocations consist of a fracture of the radius with dislocation of the distal radio-ulnar joint.  The fracture usually affects the distal third of the radius.

Galeazzi injuries are very rare in children (more commonly seen in the adult population).  The mechanism of injury is usually due to a fall on an outstretched hand with forearm rotation.

Examination findings

Examine the forearm, wrist and elbow joint.

Inspection and palpation: swelling, tenderness and likely deformity of the distal forearm and wrist. Check for any open wounds.

Range of movement: Maybe reduced at the wrist joint.

Check for signs of neurovascular compromise or compartment syndrome.  Ulnar nerve injury is uncommon.

Investigations

True AP and lateral X-rays of the forearm including the wrist and elbow (including distal humerus).

The key point here is if a distal to mid-shaft radial fracture is seen on  X-ray, have a good look for signs of distal radioulnar joint disruption.

Classification 

Galeazzi fractures are classified according to the direction of ulna displacement.

Galeazzi-equivalent fracture

A Galeazzi-equivalent fracture may occur in children.  This characterised by both

  • fracture of the distal radius
  • fracture of the growth plate of the ulna (separation of the ulnar physis), as opposed to dislocation of the distal radio-ulnar joint, DRUJ.

Treatment

All Galeazzi fracture-dislocations should be referred to orthopaedics on-call as a surgical intervention may be required for unstable or irreducible fractures.  The usual approach in children is conservative management with closed reduction and immobilisation in an above-elbow cast.  They should be followed up in the fracture clinic in 7 days.  Complications include malunion, compartment syndrome and nerve injury but these are more common in adults and if the diagnosis is delayed.  Children tend to have good outcomes with closed reduction and casting, even if the diagnosis is initially missed.

You are congratulated by the ED consultant for identifying Patrick’s Galeazzi fracture-dislocation.  You call the Orthopaedic surgeons.  It is a stable fracture and he has a successful closed reduction performed under procedural sedation in ED.  An above-elbow back slab is applied.  A few hours later, Patrick is ready to go home as he has recovered from the sedation.  On their way out, his mother asks you if he will recover fully.  You explain that he will be followed-up in the fracture clinic in 7 days but that his outcome should be good as the fracture was identified early and the post-reduction x-ray shows good alignment.  On your next day off, you decide to make a table of the differences between Monteggia and Galeazzi fracture-dislocations to aid your memory. 

[wpsm_comparison_table id=”10″ class=””]

*One way of remembering that both Monteggia and Galeazzi require review by orthopaedic surgeons is to remember that both fracture types are named after Italian surgeons!

Top tips

  • If you identify a distal to mid-shaft radial fracture, look for signs of distal radioulnar joint disruption or ulna physis disruption.
  • A useful mnemonic to remember the key differences between Monteggia and Galeazzi fracture-dislocations is MUGR (Monteggia fractured Ulna, Galeazzi fractured Radius)

Selected references

Eberl, R., Singer, G., Schalamon, J., Petnehazy, T. and Hoellwarth, M.E., 2008. Galeazzi lesions in children and adolescents: treatment and outcome. Clinical orthopaedics and related research466(7), pp.1705-1709.

Johnson NP, Smolensky A. Galeazzi Fractures. [Updated 2019 May 2]. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2019 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK470188/

Shoulder x-ray interpretation

Cite this article as:
PJ Whooley and James Foley. Shoulder x-ray interpretation, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.29653

Don’t be bamboozled by a paediatric shoulder x-ray. Use an ABCD approach and pick up some tips and tricks in our step-by-step guide.

A – An adequate x-ray 

Is it the right patient and do you have the 2 views you want to see? The typical views are AP (external rotation) and the scapular Y view. (Not sure why then thisx meme may help).  Occasionally an axillary view is added to assess for dislocations and glenohumeral instability. 

B – Bones

Go through the bones one at a time. Follow the cortex of every bone in each view. Look for a disruption or a buckle in the cortex or any fracture fragments. They should all be smooth.  

  • The clavicle is a good bone to start with – it is by far the most common paediatric shoulder injury. Midshaft fractures account for 80% of clavicle fractures. Make sure there are no distal or medial fractures as they can often be subtle. 
  • Move onto the proximal humerus – check the epiphysis and metaphysis. A normal humeral head looks like a walking stick on the AP view. The most common fracture of the humerus is a metaphyseal fracture. Metaphyseal fractures occur in ages 5-12 and Salter-Harris fractures outside of this range. 
  • Don’t forget the scapula, seen best on the Y view. Management is conservative but a fracture here indicates a significant trauma. 

Like the paediatric elbow, the paediatric shoulder has ossification centres, so x-ray appearances differ depending on the age of the child.

At birth, the humeral diaphysis, mid position of clavicle and the body of the scapula are ossified – the rest are essentially cartilage.

The proximal humerus has three ossification centres:

  • Head – 1 year of age
  • Greater tubercle – 3 years
  • Lesser tubercle – 5 years

  • The scapula has 7 secondary ossification centres. 
Ossification centres of the scapula

Look carefully for the following two – if they appear early they may be the only sign of an avulsion fracture:

  • The sub-coracoid ossificiation centre appears between 8 to 10 years and completely fuses between 16 and 17 years of age, forming the upper third of the glenoid articular surface . If it appears before the age of 8, this may indicate an avulsion (pulled by the long head of biceps at its attachment to the superior glenoid). 
  • The inferior glenoid ossification centre, appears at the lower two-thirds of the glenoid articular surface. It grows and fuses to form a horseshoe shaped epiphysis that combines with glenoid rim and sub-coracoid ossification centre. This appears between 14 and 15 years (although sometimes as young as 11 years), with complete fusion by 17 to 18 years. It can be difficult to view on standard radiographs but sometimes it can be seen on the Grashey (AP oblique) view 

A top tip: If you are unsure whether what you are seeing is an avulsion fracture or a simple ossification centre, then press directly on the patient where the fragment is. If this isn’t painful then it is highly likely to be an ossification centre and not an avulsion. Range of movement is another great give-away – it is quite hard to have an avulsion fracture and intact range of movement! If in doubt, speak to a friendly radiologist (in hours) or be conservative and place in an arm sling and bring back to clinic (out of hours) for re-assessment (when the x-ray will have been reported).

Don’t forget the other bones that don’t make up the shoulder. Have a look for rib fractures, and if you see old healing rib fractures then consider non accidental injury.

C – Connections & Connective Tissue

Are all the bits connected to where they should be? Ask yourself a few questions when you’re looking at the different joints.

Glenohumeral joint:

  • Do the articular surfaces of the humerus and glenoid have 2 parallel lines with an even joint space?
  • Does the humeral head sit evenly on the glenoid in all views?
  • Does the humeral head sit adjacent to the glenoid on the AP view? Does it sit over the glenoid on the Y view? If the answers to these questions are no, and instead the humeral head is lying under the coracoid process, this indicates an anterior shoulder dislocation

Anterior Shoulder Dislocation (AP and Y views).The humeral head is located beneath the coracoid on the AP view and no longer located centrally on the Y view. In addition there is flattening of the humeral head suggesting a Hill Sachs lesion (more on this in the upcoming shoulder dislocation post)

  • Has the humeral head lost its characteristic walking stick appearance on the AP view? Does it instead look rounder, like a light bulb? If the answer to these questions is yes, this suggests a posterior shoulder dislocation.
  • Is there a joint effusion or lipohaemarthorsis present? This could indicate an intra-articular fracture of the glenoid or the humeral head. 
Case courtesy of Dr Garth Kruger, Radiopaedia.org. From the case rID: 21129

Acromioclavicular (AC) joint:

  • Does the bottom of the acromion lines up with the bottom of the distal clavicle? If there’s a step, think clavicle fracture or physeal injury
Normal alignment of the AC joint
  • Is there widening of the acromioclavicular joint (normal is 5-8mm) or coracoclavicular distance (normal is 10-13mm)? A widened AC joint > 8mm suggests an AC ligament rupture. If the coracoclavicular (CC)  distance is >13 mm consider CC ligament rupture. If you’re unsure, get weighted views of both AC or CC joints to compare each side (literally with the child holding weights in each hand to stress the joints).
AP view of shoulder

D – Don’t forget the other tissues

Always look around the area to look for foreign bodies or subcutaneous emphysema indicating a pneumothorax or pneumomediastinum. If there are, then a dedicated chest x-ray should be performed.

And finally, although the above may seem complicated, realistically common things are common.

  • Clavicle Fractures. By far the most common. 80% are mid-shaft and occur following a fall onto the outstretched hand or shoulder or direct trauma from a seatbelt or during sport.
  • Proximal humeral fractures. These occur in older children. 
  • Anterior shoulder dislocation. Usually in older children playing sports. Falls result in forced ABDuction, external rotation, and extension. Account for 95% of shoulder dislocations. 

Don’t miss

  • Acromioclavicular Joint injuries – widening or step at acromioclavicular joint and/or increased coraco-clavicular distance. 
  • Rib fractures – healing rib fracture? Consider NAI

References

  1. JS. Zember, ZS Rosenberg, S. Kwong, SP. Kothary, MA. Bedoya. Normal Skeletal Maturation and Imaging Pitfalls in the Pediatric Shoulder.  Radiographics. 2015 Jul-Aug;35(4):1108-22
  2. https://radiopaedia.org/articles/paediatric-shoulder-radiograph-an-approach

Soft tissue knee injuries

Cite this article as:
Lisa Dann. Soft tissue knee injuries, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.25908

Sam, a 12-year-old boy, presents to your department after a soccer blitz. He was tackled, heard a pop, and now can’t weight bear on his right knee.

As popularity and intensity of children’s sports increases there are increased demands placed on children and adolescents. This has resulted in an increased presentation of children like Sam. They can present with knee pain that is traumatic or atraumatic, acute or chronic. Paediatric patients are particularly vulnerable to overuse injuries involving the physes and apophyses due to their inherent weakness (see post, hyperlink article on fractures around knee).

Along with these there has also been an increase in soft tissue injuries. These are seen more commonly in older children/adolescents as their bones become stronger and are less likely to fracture with age.

History/examination

Important points to note on the history include:

  • If there was clear onset of pain
  • Traumatic or atraumatic
  • Duration of pain
  • Previous injury/surgery
  • Site of the pain (try be as specific as possible)
  • Severity of pain
  • Nocturnal pain
  • Systemic symptoms
  • Associated swelling (intermittent or progressive)
  • Contralateral injuries (may result in abnormal gait placing additional pressure on knee)
  • Hip or back pain

Recalling the anatomy of the knee makes evaluating the site of pain easier.  The following make up the knee and all can be can be injured/inflamed and cause pain.

  1. Bones around knee – femur ends at lateral and medial condyles which articulates with tibial plateau and anteriorly the patella unsheathed in the patellar tendon.
  2. Ligaments – anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial and lateral collateral ligaments.
  3. Meniscus – medial and lateral menisci act as shock absorbers and interdigitate into the ACL and PCL for more stability.
  4. Bursae – supra-patellar bursa, infra-patellar bursa, pre-patellar bursa, and pes anserine bursa (medial aspect of knee).
  5. Tendons – quadriceps tendon (inserts into patella), patellar tendon (inserts into tibial tuberosity)
  6. Other – iliotibial band (fibrous support of fascia lata originating at the external lip of iliac crest and inserting into the lateral condyle of the tibia).

Examination in the acute setting is often difficult and may be limited. This is due to swelling, pain and anxiety. Try your best to be as detailed as possible but ensure you note any red flags on examination. These are:

  • Inability to do straight leg raise (extensor mechanism rupture)
  • Ligamentous laxity
  • Catching, locking or giving away (meniscal injury)
  • Inability to fully straighten the knee

After a thorough history and examination you discover he was tackled and the other player’s foot landed on the lateral aspect of his knee. On examination you find a swelling on medial aspect of the knee and laxity of the medial collateral ligament when valgus stress is placed on the right knee.  You clinically diagnose a medial collateral ligament injury. He is placed in a brace and referred to orthopaedic clinic.

Injured ligaments are considered “sprains” and are graded on a severity scale.

  • Grade 1 sprains: The ligament is mildly damaged. It has been slightly stretched, but is still able to help keep the knee joint stable.
  • Grade 2 sprains: The ligament has been stretched to the point where it becomes loose. This is often referred to as a partial tear of the ligament.
  • Grade 3 sprains: This type of sprain is most commonly referred to as a complete tear of the ligament. The ligament has been split into two pieces, and the knee joint is unstable.

Ligament specific examinations:

  • Anterior and posterior drawer tests – asses anterior and posterior cruciate ligament integrity.
  • Lachman test – assesses ACL integrity. Most sensitive test for ACL rupture. Non-dominant hand cups and support knee. Ensure quads and hip flexors relaxed for it to work. Dominant hand grasps proximal tibia, knee flexed at 20-30 degrees. Pull sharply. Tibia shouldn’t move much and should have distinct end point.
  • Posterior sag test – patient supine, hip flexed at 45 degrees and knee at 90 degree. Look at knee from lateral position. If PCL damaged you’ll see tibia sagging posteriorly.
  • Varus and valgus stresses – assess integrity of medial and lateral collateral ligaments. Compare both sides for laxity.

Management:

  • Unstable joints require a thorough examination of neurovascular status, orthopaedic consultation and very close follow up.
  • ACL tears often have poor healing abilities and may require surgical repair if injury is significant.
  • PCL is much better at healing itself than ACL and low grade tears are managed non-operatively with grade 3 or higher needing reconstruction.
  • Collateral ligament injuries have good healing potential so rest, ice, bracing and slow advancement of range of motion is the management primarily undertaken.

A short while later one of Sam’s team mates, Patrick, presents to ED. He was also playing in the soccer blitz. He got sudden knee pain when turning and his knee is now locked. Following assessment you suspect a meniscal injury.

Meniscal injuries

Meniscal injuries can be traumatic or atraumatic. Suspect if the knee is locked, there was a twisting mechanism, a tearing sensation, or an effusion.

Specific examinations include:

  • McMurray test – patient supine, hip and knee flexed at 90 degrees. Non-dominant hand placed over joint line. Dominant hand grasps patient’s heel and internally and externally rotates tibia exerting valgus and varus forces while extending the leg. This helps to grind on either the medial or lateral menisci. Pain, popping or clicking is a positive test.
  • Appley compression test – the patient lies prone with the knee bent at 90 degrees. The examiner rotates the leg externally and internally several times under simultaneous vertical pressure. A painful pop can point to a meniscal injury.

Treatment includes physiotherapy to compensate for the tear but surgical management may ultimately be required. Follow up with orthopaedics is required.

Patrick’s sister was also brought for review. She is 15 years old and has been having intermittent knee pain for the last few months but it gets much worse after she plays sports. She also says it really hurt her after the cinema yesterday. You suspect patellofemoral pain syndrome.

Patellofemoral pain syndrome (PFPS)

The pain is frequently described as anterior but is often poorly localised. It may feel like it’s “under” or “around” the patella. Pain is classically exacerbated by prolonged periods of sitting, use of stairs and squatting (theatre sign). Pain may be present for several weeks, exacerbated by activity and relieved after periods of rest. Frequently there is a deterioration in sports performance or inability to participate prompts patients to seek medical review.

Clinical examination should look for gait abnormalities, increased lumbar lordosis, and any asymmetry in hips or lower extremity. It is not uncommon to have reduced flexibility in the hamstrings or quadriceps.

Clarkes sign – positive in PFPS. Patient supine, knee extended. Grab the superior pole to the patella with thumb and index finger and have the patient activate the quadriceps while you inhibit the patellar movement. This causes grinding of the articular surface between patella and femur. Pain is indicative of PFPS.

Investigations are not routinely required. However, knee radiographs may assist in ruling out other conditions such as osteochondritis dissecans of the knee/patella and stress fractures of the patella. Radiographic imaging in PFPS is not diagnostic. It is necessary to combine any findings with your clinical examination.

Management of this is conservative as it is a self-resolving condition. It typically resolves over weeks to months but has been known to take up to two years for complete resolution of symptoms. Management involves reduction in activity (complete cessation usually not required), ice, rest, anti-inflammatory for pain control (short term use), avoidance of aggravating exercises (e.g. squatting) and some find relief with taping/knee-braces. Exercises that strengthen and increase flexibility of the quadriceps, hamstrings, soleus and gastrocnemius muscles are also recommended.

Further specific examinations and possible causes of non-specific knee pain

  • Ask the patient to tighten knee and palpate the quadriceps tendon at superior pole (tenderness indicates possible tendonitis), straight leg raise (assessing quadriceps strength and integrity).
  • Palpate body of patella for tenderness (Sinding-Larsen syndrome) and then patellar tendon and tibial tuberosity (Osgood-Schlatter syndrome).
  • Palpate the medial side of patella (possible inflamed medial plica band) and also palpate the proximal tibial surface (medial anserine bursa- pain, swelling, tenderness may indicate bursitis).
  • Feel under the patella (tenderness on articular surface could indicate patella-femoral syndrome).
  • Lateral – assess for patellar instability (need quadriceps relaxed and knee flexed at 30 degrees). Apprehension indicates patellar laxity and potentially previous dislocation.
  • Joint line – bend the knee and palpate either side slowly and carefully. Try to localize as much as possible. Tenderness may indicate a meniscal tear.
  • Hamstring muscles: With the knee flexed palpate the hamstring muscles. Laterally is the biceps femoris and medially semi-tendinosus and semi-membranosus. Chronic tightness may be the cause of knee pain.
  • Patellar ballottement- effusion

Bottom line

A thorough history and examination can greatly assist in reaching the diagnosis. A correct diagnosis helps to properly counsel patients and appropriately manage their expectations. Without proper treatment, knee injuries can lead to chronic knee problems, early onset arthritis, injury to surrounding tissues, and prolonged healing times. Missed injuries can also cause recurrent cartilage damage, instability in the knee, and unnecessary time away from physical activity. It is our duty to diagnose these injuries in a timely manner and provide appropriate advice, support and follow up.

Below is a useful table outlining the causes of intrinsic knee pain, separated by site of pain on examination (table 1).

References

Finlayson C. Knee injuries in the young athlete. Pediatr Ann. 2014;

Brooke Pengel K. Common overuse injuries in the young athlete. Pediatr Ann. 2014;

Beck NA, Patel NM, Ganley TJ. The pediatric knee: Current concepts in sports medicine. J Pediatr Orthop Part B. 2014. doi:10.1097/BPB.0b013e3283655c94.

Calmbach WL, Hutchens M. Evaluation of patients presenting with knee pain. Part II Am Physician. 2003.

PEM Playbook Knee Pain podcast https://pemplaybook.org/podcast/knee-pain/

Tillaux fractures

Cite this article as:
Tadgh Moriarty. Tillaux fractures, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.26111

Jenny is a 14-year-old girl who was at soccer training when she had an awkward injury to her left ankle. She was running for the ball when her foot caught in a clump of grass and she externally rotated her leg while her foot remained planted. While the pain was instantaneous, there was very little swelling. Her father has brought her in remarking that ‘it’s probably just a sprain’. But as you call her down to the cubicle to examine her, you think there might be more to it.

Incidence

Tillaux fractures are a type of ‘transitional’ ankle fracture which occur almost exclusively in adolescents. These occur during the unique closure pattern of the distal tibial physis. This closes over an eighteen-month period; first in the middle, then medially and finally laterally. During the closure, this area is vulnerable to these distinctive transitional fractures; the triplane fracture and the Tillaux fracture.

These fractures account for roughly 3% of paediatric ankle fractures. They are seen more commonly in females and tend to occur at slightly different ages depending on gender. It tends to occur later than a triplane fracture; between 12-14 years in girls and 15-18 years in boys.

Mechanism

This Salter-Harris 3 fracture occurs at the anterolateral distal tibial epiphysis. It tends to cause avulsion of the tibial fragment by the tibiofibular ligament; this strong ligament extends from the anterior aspect of the lateral distal tibial epiphysis to the anterior aspect of the fibula. The lack of a fracture through the coronal plane distinguishes this injury from that of a triplane fracture.

This injury pattern occurs usually through a combination of supination and external rotation of the foot in relation to the leg. It usually occurs through low-velocity trauma for example in skateboard accidents or sports with a sliding injury.

Presentation

These injuries are almost exclusively seen in adolescents. Similar to most ankle injuries there will be a history of trauma, symptoms of pain, swelling, and an inability (or painful) weight-bearing.

The clinical exam often reveals localised tenderness to the anterior joint line. This contrasts with a sprain where the tenderness is usually below the joint line. Marked displacement is prevented by the fibula.

Imaging

Do not be misled by lack of swelling – have a low threshold to image injuries which present with an inability to weight bear (at least four steps). When requesting an ankle x-ray AP and lateral views will be included as standard – if you have a high index of suspicion for a Tillaux fracture ask for an oblique or ‘mortise’ view – this can improve your detection by avoiding the obstructed view through the fibula and potentially making the subtle fracture more apparent.

This injury can sometimes have an associated ipsilateral tibial shaft fracture or a proximal fibular injury. During your clinical exam if you illicit tenderness proximal to the ankle, then include a full-length tibia/fibula x-ray with your request.

Does this injury require a CT? Perhaps! See the controversy section below for a more thorough explanation. CT is generally only required by the orthopaedic team to assist with surgical planning.

Image courtesy of Orthobullets.com

Image showing CT scan of same fracture with >2mm displacement courtesy of Orthobullets.com

This injury however often requires a CT scan to assist the orthopaedic team in deciding between conservative and operative management.

A study by Horn et al showed CT as being more sensitive than plain film at detecting fractures with greater than 2mm displacement (the cut-off point adopted for operative fixation).

Treatment

These fractures are important as they involve the weight-bearing surface and can lead to significant morbidity if missed. The treatment of these injuries is not uniform – different methods and cut-offs are described in different case reports and case series. Having that said the current marker for operative versus conservative treatment is the degree of displacement of the fracture fragment.

Those with < 2mm displacement can generally be treated conservatively. This usually involves an above-knee cast for up to 4 weeks (to control the rotational component) followed by either a walker boot or below-knee cast for a further 2-4 weeks. This conservative approach is well documented in having a satisfactory outcome.

Those with displacement >2mm generally require intervention to ensure articular congruity of the joint surface is restored. Intervention can occur in different forms; some may be suitable for a closed reduction under procedural sedation (or general anaesthetic). Different reduction techniques exist however longitudinal traction while the knee is flexed followed by internally rotating a maximally dorsiflexed ankle seems to achieve greater anatomic reduction. A review by Lurie et al concluded those left with a residual gap of more than 2.5mm led to worse functional outcomes. Therefore post-reduction radiological confirmation should show minimal displacement (the figure of <2mm tends to be favoured in the literature) otherwise operative intervention is required. Many orthopaedic surgeons favour CT as the post-reduction imaging modality of choice and then follow this reduction with serial radiographs to confirm maintenance of the reduction over time.

Operative intervention can involve K-wire insertion, use of lag screws or a novel technique involving percutaneously inserted wires with arthroscopic or radiological guidance. This new technique is seen as less invasive and as-effective but is technically complex and demanding. If this injury presents with a neurovascular compromise or critical skin then emergent surgery is indicated. This is, thankfully, rare.

What to tell the patient

Recovery: Both operative and conservative measures tend to require up to 8 weeks of immobilisation followed by a rehab phase. This phase will vary depending on the age of the patient. Most patients have a good outcome with 86% having complete recovery and no sequelae. Very few will have pain or limitation of ankle movement. Late presentation and a non-anatomical reduction will increase the risk of this.

Complications

These are less common than other ankle fractures; delayed or malunion, osteonecrosis of the distal tibial epiphysis, premature growth arrest and compartment syndrome are all very rare occurrences. Early-onset arthritis can occur, those with late presentations or missed fractures are more at risk.

Operative intervention carries the additional (albeit small) risk of physeal damage from direct pressure by blunt instruments and inadvertent damage to the superficial peroneal nerve.

Controversies

Radiological evaluation remains controversial. Plain x-ray usually identifies the transitional fracture, and the degree of displacement. However, CT (ideally with 3D reconstruction) is more accurate in estimating the degree of displacement and fracture separation.

Case courtesy of Dr Yasser Asiri, Radiopaedia.org. From the case rID: 64778

CT can help in identifying the number and position of fragments. The issue of whether CT or MRI alters treatment or prognosis when compared with plain X-ray has not been fully investigated. Limited research has been carried out on whether CT, with its greater accuracy, actually affects treatment or patient outcome. Liporace et al in 2012 found that interobserver and intra-observer agreements about primary treatment plans did not differ significantly between radiography alone and radiography plus CT. This showed that the addition of CT did not actually change the impression about the degree of displacement in each case. This raises the question as to whether CT really alters outcomes despite having perceived greater benefits.

Jenny is found to have significant tenderness about her distal tibia on exam and an x-ray confirms a Tillaux fracture which is minimally displaced. She is placed in an above-knee backslab and referred to the orthopaedic fracture clinic. She is left disappointed that she will miss this season’s matches, but thankfully you didn’t misdiagnose this as a sprain!

References

Orthobullets.com/paediatrics/4028/tillaux-fractures

Wheelers textbook of orthopaedics (updated 2015) Clifford J Wheeless Tintinnali 7th Ed

Tiefenboeck TM, Binder H, Joestil J et al. Displaced juvenile Tillaux fractures: surgical treatment and outcome. Wien Klin Wochenschr. 2017; 129 (5-6):169-175

Rosenbaum AJ, DiPreta JA, Uhl RL. Review of distal tibial epiphysis transitional fractures. Orthopaedics. 2012;35(12):1046-1049

Horn BD, Cristina K, Krug M, Pizzutillo PD, MacEwen GD. Radiologic evaluation of juvenile Tillaux fractures of the distal tibia. J Pediatr Orthopaedics. 2001; 21(2): 162-4

Cooperman DR, Spiegel PG, Laros GS. Tibial fractures involving the ankle in children. The so-called triplane epiphyseal fracture. J Bone Joint Surg Am. 1978 Dec. 60 (8):1040-6

Panagopoulos A, van Niekerk L. Arthroscopic assisted reduction and fixation of a juvenile Tillaux fracture. Knee Surg Sports Traumatol Arthrosc 2007;15:415-417

Manderson EL, Ollivierre CO. Closed anatomic reduction of a juvenile tillaux fracture by dorsiflexion of the ankle. A case report. Clin Orthop Relat Res. 1992 Mar. (276):262-6.

Crawford AH Triplane and Tillaux fractres: is a 2mm residual gap acceptable. J Pediatr Orthop. 2012 Jun;32 Suppl1:S69-73

Schlesinger I, Wedge JH. Percutaneous reduction and fixation of displaced juvenile Tillaux fractures: a new surgical technique. J Pediatr Orthopaedics. 1993;13:389-391

Stefanich RJ, Lozman J. The juvenile fracture of Tillaux. Clin Orthopaedics Relat Res. 1986;210:219-227

Kaya A, Altay T, Ozturk H, Karapinar L. Open reduction and internal fixation in displaced juvenile Tillaux fractures. Injury 2007;38:201-205

Choudhry IK, Wall EJ, Eismann EA. Crawford AH, Wilson I. Functional outcome analysis of triplane and tillaux fractyres after closed reduction and percutaneous fixation. J Pediatr Orthop. 2014;34:139-43

Jennings MM, Layaway P, Schubert JM. Arthroscopic assisted fixation of juvenile intra-articular epiphyseal ankle fractures. J Foot Ankle Surg 2007;46: 376-386

Rockwood and Wilkin’s fractures in children. 6th Edition.2006

Kim JR, Song KH, Song KJ, Lee HS. Treatment outcomes of triplane and Tillaux fractures of the ankle in adolescence. Clin Orthop Surg. 2010 Mar. 2 (1):34-8

Haapamaki VV, Kiuru MJ, Koskinen SK. Ankle and foot injuries: analysis of MDCT findings. AJR Am J Roentgenol. 2004 Sep. 183 (3):615-22

Charlton M, Costello R, Mooney JF et al. Ankle joint biomechanics following transepiphyseal screw fixation of the distal tibia. J Pediatr Orthopaedics. 2005;25: 635-640

Liporace FA, Yoon RS, Kubiak EN, Parisi DM, Koval KJ, Feldman DS, et al. Does adding computed tomography change the diagnosis and treatment of Tillaux and triplane pediatric ankle fractures?. Orthopedics. 2012 Feb 17. 35 (2):e208-12

Lurie B, Van Rysselberghe N, Pennock AT, Upsani VV. Functional outcomes of Tillaux and triplane fractures with 2-5millimetres of intra articluations gap. J Bone Joint Surg Am. 2020;102:679-686

Rapariz AJ, Avocets G, Gonzalez-Herman P, Texas et al. Distal tibial triplane fractures: long term follow up. J Pediatr Orthopaedics. 1996; 16: 113-118.

Elbow dislocations

Cite this article as:
Becky Platt. Elbow dislocations, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.28344

You are called to assess 14-year old Oliver who has presented to your ED by ambulance with an elbow injury.  He dived to make a save while playing football and landed on his outstretched hand.  He reports feeling a click in his elbow, followed by excruciating pain.  He was given methyoxyflurane in the ambulance which has helped. 

Assessment of any child and examination of their elbow should be approached in an age-appropriate and systematic way.  In addition to examining for bony tenderness, vascular and neurological status should be tested.

Oliver’s elbow looks significantly swollen, deformed and bruised.  You feel for a radial pulse – it’s there – and  undertake a neurovascular assessment, which is intact.  You prescribe him some intranasal fentanyl and order AP and lateral x-Rays of his elbow.

The elbow is an incredibly stable joint due to the way the humerus and ulna articulate (giving anterior-posterior and varus-valgus stability), strengthened by the medial and lateral collateral ligaments and the joint capsule.  Muscles and tendons further strengthen this ring.  A significant amount of force is needed to dislocate the elbow. 

Traumatic dislocation of the elbow is rare in the paediatric population comprising only 3-6% of all childhood elbow injuries, but the most common large joint dislocation (Lieber et al., 2012).  It is usually the result of a fall onto an outstretched hand, often with a large amount of force involved.  

Clinically, it is obvious that there is significant injury around the elbow; this is not something you will miss or be tempted not to x-ray.  Displaced supracondylar fractures can sometimes be confused with elbow dislocation as both present with a grossly swollen elbow and significant pain.  A quick and easy way to distinguish the two clinically is to palpate for the equilateral triangle formed by the olecranon and the two epicondyles: this is lost in elbow dislocation as the humerus creates a fullness in the antecubital fossa. There is no need to check movements in a deformed elbow but be sure to undertake a neurovascular assessment as a priority.  

The easiest way to classify simple elbow dislocations is by describing the direction of ulna dislocation in relation to the distal humerus.

Classification of elbow dislocations

90% of paediatric elbow dislocations are postero-lateral with the radiographic appearance as below:

But beware: elbow dislocations rarely present in isolation.  They often coexist with other elbow injuries. Associated fractures are likely to occur prior to closure of the epiphyses; when they are closed, collateral ligaments are likely to be ruptured (Lieber et al., 2012). The most common associated fracture is a medial epicondyle avulsion which can become incarcerated in the joint – scrutinize the elbow x-rays for associated fractures. This illustrates the importance of knowing CRITOE.

Elbow dislocation with medial epicondyl avulsion from Orthobullets.com. The white arrow points to the avulsed medial epicondyl while the red arrow shows where it has been avulsed from.

Oliver returns from x-ray and you review his films. You note the posterior dislocation but cannot see any associated fractures on Oliver’s films. You contact your orthopaedic team for further assistance.

Management

Many elbow dislocations reductions can be carried out in the emergency department with adequate muscular relaxation and appropriate analgesia.  A reasonable amount of force is often required to achieve reduction using traction on the forearm with counter-traction around the elbow.  This should be carried out or supervised by a clinician experienced in the procedure. 

Common pitfalls in elbow reduction

Be very careful to conduct a thorough neurovascular assessment before attempting reduction. The brachial artery and median nerve may become stretched over the displaced proximal ulna and ulnar nerve can become damaged when medial epicondyle avulsions complicate elbow dislocations. If a deficit is found after reduction you need to know whether it was present before you attempted relocation…

And if you can’t reduce the dislocation go back and have another look at the x-ray – it could be due to an avulsed medial epicondyle in the joint. Any elbow dislocation with an incarcerated piece of avulsed bone in the joint must be reduced in theatre and not in the ED.

Complications

Possible complications following elbow dislocation include residual limitation of the range of movement, recurrent instability, neurovascular injury, avascular necrosis of the epiphyses and degenerative arthritis. Early diagnosis and stable reduction, with fixation of concomitant fractures if necessary, are generally associated with better outcomes.  For the Emergency department clinician, it is therefore critical that children with this injury are assessed and managed with the minimum possible delay, ensuring that associated fractures are recognised and managed appropriately.

After sedation with ketamine, Oliver’s elbow is reduced in the department with a satisfying clunk signifying reduction.  His elbow is put through a full range of movement to test joint stability and an above elbow backslab applied.  You order repeat x-Rays to evaluate the position and to check for the joint spacing and any fracture fragments within the joint as this would require surgical intervention.  The post-reduction films are good and Oliver’s neurovascular assessment remains normal and he leaves your ED with a follow-up appointment in fracture clinic in a week’s time.

References

Cadogan, M. (2019) Elbow Dislocation https://lifeinthefastlane.com/elbow-dislocation/

Edgington, J. (2018) Elbow Dislocation – Pediatric.  

https://www.orthobullets.com/pediatrics/4013/elbow-dislocation–pediatric

Lieber, J., Zundel, S., Luithle, T., Fuchs, J., & Kirschner, H-J. (2012) Acute traumatic posterior elbow dislocation in children.  Journal of Pediatric Orthopaedics B. 21(5) 474-481

Rasool, M. N. (2004). Dislocations of the elbow in children. The Journal of Bone and Joint Surgery, 86, 1050–1058. 

Sibenlist, S. & Biberthaler, P. (2019) Simple Elbow Dislocations in Biberthaler, P., Sibenlist, S. & Waddell, J.P. Acute Elbow Trauma.  Fractures and dislocation injuries (eBook).  Springer

Sofu, H., Gursu, S., Camurcu, Y., Yildirim, T., & Sahin, V. (2016). Pure elbow dislocation in the paediatric age group. International Orthopaedics, 40(3), 541–545

Radial head and neck fractures

Cite this article as:
Becky Platt. Radial head and neck fractures, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.21165

Aisha is 10 years old. She loves gymnastics but today, during a cartwheel, she injured her right elbow.  Aisha is cradling her right arm in her left hand and is reluctant to move it, despite having had ibuprofen at home.  

 

Assessment of any child and examination of their elbow should be approached in an age-appropriate and systematic way.  In addition to examining for bony tenderness, vascular and neurological status should be tested.

 

On examination, you note swelling around the elbow, especially on the lateral aspect.  Aisha has tenderness particularly over the radial head and complains of pain on any movement especially supination and pronation.  She has normal sensory and motor function of radial, ulnar and median nerves and normal pulses, colour and capillary refill time to her hand. You prescribe further analgesia, apply a broad arm sling for comfort and order lateral and AP x-rays of her elbow.

Radial head and neck fractures comprise around 5% of all elbow injuries in children, with a peak at 9-10 years of age. They normally result from a FOOSH (‘fall onto an outstretched hand’).  Fractures through the radial head are rare in children: more commonly the physis (the growth plate: the disc of cartilage between the epiphysis and metaphysis), or radial neck will be involved.

 

Radial Neck fractures

Radial neck fractures can generally be diagnosed on lateral and AP elbow x-ray.  It’s useful to remind yourself of the elbow anatomy prior to looking at the x-ray so that you know what you’re looking for.  It’s really important to appreciate that part of the radial neck sits outside of the capsule. Most radial neck fractures occur at the level of the annular ligament, which forms a collar around the radial neck to anchor it to the ulna.

Elbow ligaments. From RCEM Learning

This means that not all radial neck fractures have a joint effusion. Don’t be fooled by a lateral elbow x-ray without a fat pad sign – this just means there’s no joint effusion; it doesn’t mean there isn’t a radial neck fracture.

The appearance can be quite subtle, so it’s useful to remind yourself what the radial neck looks like on a normal X-ray:

Normal radial neck. Case courtesy of Dr Henry Knipe, Radiopaedia.org. From the case rID: 24158

In particular, notice how the contours of the radial neck form smooth curves, as above. These smooth curves are lost in radial neck fracture:

Radial neck fracture. Case courtesy of Dr Jeremy Jones, Radiopaedia.org. From the case rID: 42688

 

Mildly angulated radial neck fracture (black arrow) and posterior fat pad (white arrow). Reproduced with permission from Emery et al. Ped Rad. 2016; 46:61-6

How are radial neck fractures classified?

Radial neck fractures were classified by O’Brien (1965)  as follows:

Type I: <30 degrees displacement

Type II: 30-60 degrees displacement

Type III: >60 degrees displacement

O’Brien’s classification of radial neck fractures. From Orthobullets

 

Other radial neck classifications have been described so, to avoid confusion, it’s probably safest to describe the degree of displacement rather than the classification type, especially as displacement of radial neck fractures in children is uncommon.

 

How should radial neck fractures be managed?  

Most paediatric radial neck fractures are type I: undisplaced or minimally displaced.  These do really well with conservative management with immobilization in a collar and cuff.  Those with displacement of >30 degrees tend to have a worse outcome and should be referred to orthopaedics as reduction, and possible internal fixation will be required.

 

Which children need to be discussed with the orthopaedic team before they go home?

  • Any displaced radial neck fractures
  • Any radial neck fractures with a second elbow injury

 

Radial neck fractures – do not miss…

30-50% of children with a proximal radial fracture have another fracture – examine the child and their x-rays very carefully.  Having a second injury is associated with a poorer outcome. The most common associated injuries are:

  • elbow dislocations
  • medial epicondyle fractures
  • olecranon fractures

 

Radial neck fractures can also be associated with compartment syndrome of the forearm, although thankfully this is rare.   Compartment syndrome is a limb-threatening condition caused by increased pressure within the closed space of a muscular compartment which causes compression of the nerves, muscles, and vessels within the compartment.  Untreated, this can lead to ischaemic injury within 4-8 hours.

 

Assessing for compartment syndrome – the 5 Ps

  • Pain – the most important indicator.  Often diffuse and progressive, not resolved by analgesia, worsened by passive flexion of the injury.
  • Pallor – assess distal to the injury.  Dusky or cool skin (compared to the other side) or delayed capillary return.
  • Pulse – weak or absent pulse indicates poor perfusion,
  • Paralysis – assess active movement of the wrist and fingers.  This may cause pain but the purpose is to assess ability to move.
  • Paraesthesia – ask about pins and needles or a feeling of the hand “falling asleep”.  Assess sensation with light touch or using an object such as a pen lid.

Any concerns about potential compartment syndrome must be escalated to an ED or orthopaedic senior without delay as this is a time-critical situation.

 

Radial Head fractures

Like radial neck fractures, radial head fractures are also most often due to a FOOSH.  Unlike radial neck fractures, radial head fractures typically occur after the proximal radial physis has closed so are more common in older children. They are usually clearly visible on x-ray and the majority are undisplaced and respond well to conservative management in a collar and cuff or sling.  Displaced fractures of the radial head are rare and will need an urgent orthopaedic referral.

Radial head fracture. Case courtesy of Dr Henry Knipe, Radiopaedia.org. From the case rID: 24158

 

 

Aisha returns from X-Ray and you spot an undisplaced fracture of the radial neck, visible on the AP and lateral views.  You remember that associated fractures are common and so have a careful look for other injuries and check the epiphyses using the CRITOE rule.  Aisha has an isolated, non-displaced radial neck fracture with no other injuries: you pop her in a collar and cuff and organize virtual fracture clinic follow up.  You make sure to give her and her family advice about analgesia and signs of any neurovascular compromise before they leave.

 

References

Barclay, T. (2019) Elbow Joint. Innerbody https://www.innerbody.com/image/skel14.html

Davies, F., Bruce, C. E., & Taylor-Robinson, K. J. (2011). Emergency Care of Minor Trauma in Children. London: Hodder & Stoughton.

De Mattos, C. B., Ramski, D. E., Kushare, I. V., Angsanuntsukh, C., & Flynn, J. M. (2015). Radial Neck Fractures in Children and Adolescents. Journal of Pediatric Orthopaedics, 36(1), 6-12.

Edgington, J. & Andras, L. (2018) Radial head and neck fractures – pediatric https://www.orthobullets.com/pediatrics/4011/radial-head-and-neck-fractures–pediatric

Emery, K. H., Zingula, S. N., Anton, C. G., Salisbury, S. R., & Tamai, J. (2016). Pediatric elbow fractures: a new angle on an old topic. Pediatric Radiology, 46(1), 61–66.

Gaillard, F. https://radiopaedia.org/articles/radial-head-fractures?lang=us Accessed 23/06/2019

Gomes, C. & Lowsby, R. (2018) Elbow Injuries.  RCEM Learning https://www.rcemlearning.co.uk/reference/elbow-injuries/

Hill, C. E., & Cooke, S. (2017). Common Paediatric Elbow Injuries. The Open Orthopaedics Journal, 11, 1380–1393.

Kraus, R. (2014). The pediatric vs. the adolescent elbow. Some insight into age-specific treatment. European Journal of Trauma and Emergency Surgery, 40(1), 15–22.

Lampert, L. (2016). Compartment Syndrome – The 5 Ps. Ausmed. Retrieved from https://www.ausmed.com/cpd/articles/compartment-syndrome

Nicholson, L. T., & Skaggs, D. L. (2019). Proximal Radius Fractures in Children. The Journal of the American Academy of Orthopaedic Surgeons, 00(00), 1–11.

Nickson, C. (2018) Compartment Syndrome. Life in the Fast Lane https://lifeinthefastlane.com/compartment-syndrome/

O’Brien, P.I. (1965) Injuries involving the proximal radial epiphysis.  Clinical Orthopaedic related Research, 41, 51-58.

Shabtai, L., & Arkader, A. (2016). Percutaneous reduction of displaced radial neck fractures achieves better results compared with fractures treated by open reduction. Journal of Pediatric Orthopaedics, 36(4), S63–S66.

Tan, B. H., & Mahadev, A. (2011). Radial neck fractures in children. Journal of Orthopaedic Surgery (Hong Kong), 19(2), 209–212.