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.
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.
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.
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.
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.
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.
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.
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.
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.
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!
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