Topic | Hand Examination and Pathology |
Author | Segn Nedd |
Duration | 2.5 hours |
Equipment required | Finger bandages, zimmer boards, plaster of paris sets, green sterile needle or cauterisation device. |
- Basics (30 minutes)
- Main Session (2 x 15 minutes) case discussions covering key points and evidence
- Advanced Session (2 x 20 minutes) case discussions covering diagnostic dilemma, advanced management
- Sim scenario (30 minutes)
- Quiz (5 minutes)
- Infographic sharing (5 minutes): 5 take home learning points
Expectation is for the learners to have watched or read one of the basic anatomy/pathology links before the session
Anatomy and Common injuries:
- https://litfl.com/bscc/clinical-anatomy/hand-anatomy/
- https://dontforgetthebubbles.com/finger-injuries-basics-and-bones/
- https://teachmeanatomy.info/upper-limb/bones/bones-of-the-hand-carpals-metacarpals-and-phalanges/
- https://teachmeanatomy.info/upper-limb/muscles/hand/
Examination:
- https://geekymedics.com/hand-examination/
- DFTB Finger injury Basics, Know the terms to describe finger injuries: https://www.youtube.com/watch?v=_t4UIUuASOA
- Index flexor tendon injuries (lacerations, zones, assessment) https://www.youtube.com/watch?v=xrCbsjEfMcY
Management:
- Finger tips: https://dontforgetthebubbles.com/finger-tips/
- Finger collateral ligament injuries (gamekeepers thumb) https://www.youtube.com/watch?v=6F8ZK5g1BRw
- Finger collateral ligament injuries (gamekeepers thumb) https://www.youtube.com/watch?v=6F8ZK5g1BRw
Basics
(From teachmeanatomy and LITFL)
In children and adolescents, the hand is the most commonly injured body part. This is partly because the hands (including fingers) of children & young people have a tendency to fracture without as much compressive force being applied to the bones when compared with adult hands. Soft tissue injuries are also very common and can also occur as children explore the world in younger years often trapping digits in doors and through accidents during play and sporting activities.
Descriptive Terms
When describing injuries of the hand for documentation or referral purposes it is important to know the terminology that is widely in use in order to convey an accurate description to others. Injuries present on the palmar surface would be described as palmar or volar. Injuries on the back of the hand are dorsal. The proximal part of the hand is more towards the forearm, whereas the distal end is towards the fingers. The thumb lies on the radial side and the little finger is on the ulnar side.
Anatomy:
(from Radiopedia, NYSORA & teachme anatomy)
It is important to have knowledge of the underlying structures that form the hand. This will facilitate your ability to understand what you are examining and the associated pathologies that need to be considered. The hand has a complex anatomy with bony structures that are surrounded by a matrix of soft tissues including muscles, tendons and ligaments. It additionally has an intricate blood and nerve supply. We will focus on the most important structures when assessing paediatric hands in the emergency department.
Bones:
A good mnemonic to remember the position of the carpal bones is to describe them starting from the base layer level from the thumb to little finger, followed by the top layer level from the little finger to thumb.
The soft tissue structures of the hand work together with the support of the bones to facilitate movements and flexibility. The bones of the hand can be divided into three categories:
- Carpal bones – eight irregularly shaped bones located at the base of the hand. They also form part of the wrist joint as they articulate with both the radius and ulnar.
- Metacarpals – There are five metacarpals. They articulate with the carpal bones proximally and the phalanges distally.
- Phalanges – These are the bones which form the fingers. The thumb has 2 phalanges whilst each other finger has three.
The soft tissues of the hand
An intricate matrix of muscles, tendons and ligaments are present in the hand. Each having its role in assisting to support the structure of the hand and also enable good manual function and dexterity to occur.
Ligaments:
There are multiple ligaments of the hand which connect the carpal bones together but also play a vital role in the stability of the wrist joint. Some of the most clinically important ligaments in achieving this are labelled as above. Ligaments of the hand are not visible on X-ray and the best mode of imaging is MRI if there is a continued concern of injury following examination and specialist hand team review. However, increases in the spacing between bones on plain X-rays can indicate a ligament injury with clinical correlation.
Finger Ligaments:
(from the British Society for Surgery of the Hand & teachme anatomy)
The ligaments are strong structures in the hands that prevent a joint from going into an abnormal position. They are very important in the flexor pulley system of the hand- that helps to keep the flexor tendons against the phalanges so they do not bowstring on flexion of the fingers.
These ligaments are split into 3 groups. The annular, cruciate and oblique ligament of the hand.
There are 5 annular ligaments on each finger and 2 for the thumb, 3 Cruciate ligaments associated with each finger and 1 Oblique ligament that is associated with the thumb. Each ligament is named after the first initial of its group and then assigned a number depending on their position on each digit.
Hand tendons
(British Society for Surgery of the Hand/teachmeanatomy)
Tendons are classified in the hand into extensor and flexor tendons. They are strong smooth cords that connect muscles to bones
In relation to the extensor tendons of the hands, the long tendons from the forearm muscles are joined by the short tendons from the small muscles in the hand to form a complicated sheet of tendon fibres over the back of the finger. This sheet has a central band that straightens the middle joint of the finger and two lateral bands that separate and join together again to straighten the end joint of each finger.
The extensor tendons are just under the skin and are easily injured by any cut across the back of the wrist, hand or fingers. The tendons are especially vulnerable where the cut is over the back of the joints of the fingers.
There are two flexor tendons to each finger and one for the thumb. The tendons run inside tunnels (carpal) at the wrist and in the fingers, they help to bend the fingers. The tendons can be damaged by any cut across the palmar surface of the wrist or hand, especially at the finger creases where the tendons lie just under the skin. Occasionally, the tendon is detached from the bone by a violent pulling injury to the finger volar plate injury.
Flexor Tendons:
Extensor tendons:
Muscles
(from radiopedia & teachmeanatomy)
There are multiple muscles that work on different parts of the hand. However, these are often broken into two main subgroups: extrinsic and intrinsic muscles of the hand.
Extrinsic Muscles:
These are a group of muscles including the long flexors and extensors. Their name is derived from the fact that their muscle origin and bellies are outside (extrinsic to) the hand and come from the forearm (mostly humerus). The extrinsic muscles however do insert into structures in the hand
A way to further classify the extrinsic muscles relates to the side of the forearm compartment that the muscles lie within. This includes the anterior compartment and the posterior compartment.
Anterior compartment:
The anterior compartment houses muscle associated with pronation of the forearm and flexion of the wrist and fingers
The muscles in this compartment lie in three layers, superficial, intermediate & deep. The blood supply to these muscles mostly comes from the ulnar & radial arteries. They are mostly innervated by the median nerve.
Posterior compartment:
The muscles in the posterior compartment are often called the extensor muscles. They are mostly responsible for extension of the wrist and fingers. The muscles here can be divided into superficial and deep layers. These layers are separated by a layer of fascia. The nerve supply to this group of muscles comes from the radial nerve.
Intrinsic muscles of the hand:
(radiopedia & teachmeanatomy)
The intrinsic muscles of the hand (also known as the small (or short) muscles of the hand) is a term used to refer to those muscles of the hand that are intrinsic (inside) the hand. This means that they originate from and insert into the hand.
There are lots of muscles to remember when looking at the intrinsic muscles of the hands. Here are some useful mnemonics which may help you to recall them.
This mnemonic facilitates recall of the muscles in relation to their palmar position from lateral (thumb- pollicis) to medial (little finger- digiti minimi)
Further classifications are used to describe the area where these muscles lie:
Thenar muscles– three short muscles located at the base of the thumb. The muscle bellies produce a bulge, known as the thenar eminence. They are responsible for the fine movements of the thumb.
Hypothenar muscles– three muscles forming a muscular bulk called the hypothenar eminence. This is on the ulnar side of the palm of the hands. The muscle group primarily acts on the little finger.
Lumbricals – There are four lumbrical muscles in the hand, each associated with a finger. They are very crucial to finger movement, linking the extensor tendons to the flexor tendons.
Interossei -The interossei muscles are located between the metacarpals. They can be divided into two groups: the dorsal and palmar interossei. Dorsal interossei facilitate abduction and palmar palmar interossei facilitate adduction of the fingers.
Other intrinsic muscles of the hand
The other muscles in the palm include the palmaris brevis muscle. This is a small intrinsic muscle in the hand that overlies the hypothenar muscles, but is not part of the hypothenar muscle group. It is important in strengthening grip. The adductor pollicis muscle is another intrinsic muscle of the hand. It lies deep to the thenar eminence. Its role is to help adduct the thumb.
The Nervous System:
(from NYSORA)
The ulna, median, and radial nerves innervate the hand. The course of these nerves traverse the wrist. Terminal nerve branches can be easily damaged due to direct trauma to the hand. However, due to the courses the nerves of the hand take, damage can also occur following wrist injuries. Terminal branches can also be damaged by direct injury to the hand. The nerves of the hand have an important role in functionality of the hand. The radial nerve facilitates extension of the metacarpophalangeal (and wrist) joints. The ulnar nerve facilitates movement of the small muscles of the hand. The median nerve supports finger extension and the anterior interosseous branch enables thumb flexion at the interphalangeal joint and flexion of the index finger at the distal interphalangeal joint.
The corresponding dermatomal innervation of the hand (and wrist) is illustrated below.
Vasculature:
(from teachmeanatomy, orthobullets & American society of surgery for the hand ASSH)
Arising from bifurcations of the brachial artery in the cubital fossa, the radial and ulnar arteries (and their branches) supply blood to the forearm, wrist and hand. The radial artery supplies the posterolateral aspect of the forearm and is important in contributing to the blood supply of the carpal bones. The ulnar artery supplies the anteromedial aspect of the forearm. It mostly supplies blood to the elbow joint, but its branches do however help supply some of the deeper structures in the forearm and therefore some of the intrinsic muscles of the hand.
These radial and ulnar arteries merge in the hand forming the superficial palmar and the deep palmar arches.
The Deep Palmar Arch: As the radial artery continues into the hand, it wraps around the thumb and comes across the palm deeply to the soft tissues in an arch shape. Its branches supply blood to the thumb and index finger.
Superficial Palmar Arch: As the ulnar artery continues into the hand, it travels across the palm, forming a superficial arch shape. This vessel communicates with the deep palmar arch. Its branches (common digital arteries) supply blood to the fingers. These Common Digital Arteries mostly split in the palm to provide blood to two different fingers. This is through vessels that are then called the proper digital arteries to the fingers.
The thumb receives its blood supply from the digital arteries to the thumb. The largest branch is from the deep palmar arch and is called the “princeps pollicis” artery.
A note on finger nails & nailbeds:
(from teachmeanatomy)
The nail unit is a complex structure located on the dorsal surface of each finger (and toe). It has two main functions:
- Protection – protects the digits from trauma
- Sensation – assists with tactile sensation
The nail unit consists of the nail plate (finger nail as it is commonly called) and the surrounding soft tissues:
- Nail plate– this hard but flexible keratin structure forms the outer part of the nail unit
- Nail folds- skin that surround and protect the proximal and lateral parts of the nail plate
- Nail bed (sterile matrix)– lies underneath the nail plate and holds it to the distal phalanx (it does not contribute to nail plate growth).
- Germinal matrix– soft tissue proximal to the sterile matrix. This is where new nail plate growth originates.
- Lunula – white “half moon” appearance of the germinal matrix through the nail plate
- Hyponychium – area distal to the nail bed, underneath the free edge of the nail plate
- Eponychium (cuticle) – Layer of tissue which extends between the skin of the finger and proximal nail plate
Clinical Approach:
History:
(from DFTB)
It is important to ask questions around a number of pertinent topics. In order to ask the right questions that will appropriately direct your further assessment & management a really helpful memory aide is to take a “HAND” history.
Examination:
(From Geeky medics & DFTB)
The look, feel, move & function approach is generally used to examine the hand (& wrist).
As functions involve both areas they are often examined together.
Look | |
1 | Perform general inspection |
2 | Inspect the dorsum of the hands |
3 | Inspect the palms of the hands and elbow |
Careful note should be taken to ensure that full inspection is undertaken. This may identify any bruising, overlying skin changes, swelling or deformity. Remember also to always examine the joint above and the joint below.
Feel | |
1 | Asses and compare temperature of wrist and small joints of hand |
2 | Palpate radial and ulnar pulse & check capillary refill |
3 | Palpate thenar and hypothenar eminence |
4 | Asses median nerve sensation |
5 | Asses ulnar nerve sensation |
6 | Asses radial nerve sensation |
7 | Perform MCP squeeze |
8 | Bimanually palpate hand and finger joints |
9 | Palpate anatomical snuff box |
10 | Bimanually palpate the wrist joints |
It is important not to miss any neurovascular compromise when examining the wrist and hand. Findings to suggest compromise may include colour change, coolness to touch, prolonged capillary refill time and altered sensation/parasthesia.
Move | |
1 | Assess finger extension |
2 | Assess finger flexion |
3 | Assess active wrist extension |
4 | Assess active wrist flexion |
5 | Assess wrist/finger extension against resistance (radial nerve) |
6 | Assess index finger ABduction against resistance (ulnar nerve) |
7 | Assess thumb ABduction against resistance median nerve) |
Where possible movements should be actively undertaken by the patient. Take notice of any movements that are undertaken with difficulty or cause pain in undertaking.
A combination of movements described by Dawson can be used to assess motor and neurological function in the hand and wrist. This can be done by starting a game of rock, paper, scissors. The addition of the OK sign and also encouraging pronation and supination by “turning the key”, turning the door handle” or “turning the lightbulb” will allow easy testing of wrist and hand movement and functionality.
Function | |
1 | Assess power grip |
2 | Assess pincer grip |
3 | Assess picking up small objects |
4 | Supination and pronation- twisting key movement |
The next section will use cases to explore some of the common presentations and management considerations that clinicians should be aware of when seeing a child who presents to the paediatric emergency department with a hand injury.
A 4-year-old boy is brought to ED with his father. He had been playing hide & seek with his cousins. Whilst playing, he had caught his fingers in the metal-hinged side of the fire door. He presents to the department crying and had his ring finger wrapped in a wet kitchen paper towel. His X-ray was as follows:
- What does this x-ray show?
- His dad handed you a folded tissue reporting it had the end of his finger in it. What should you do with it?
- How would you manage this injury?
Discussion
(from Orthobullets, Relias media & EM News blog)
What does this x-ray show?
The patient’s x-ray shows loss of soft tissue of the ring finger. In this case there was no loss of bone but it was exposed. It is always important to get an AP & lateral view of the affected areas to properly discern this.
Finger injuries caused by fingers being caught in closing doors are extremely common presentations to the paediatric emergency department. The resulting injuries include crush injuries, fractures, avulsions, lacerations and amputations. Complete finger and fingertip amputations are more likely to occur from injuries with sharp objects and so are more common in older children. However these can still occur following finger entrapment (~ 6%) of “trapped fingers in door” presentations.
His dad handed you a folded tissue reporting it had the end of his finger in it. What should you do with it?
Keep it and try to best preserve it until a decision on viability is made by the plastics team. Patients occasionally present with an amputated finger in a bag or on ice, and they can still be eligible for replantation.
If presented in a dry towel, place the amputated finger in a saline-soaked gauze, place it in a sterile plastic bag/container to prevent it drying out.
This bag/container can then be placed in another bag/container with ice. Do not place any of the loose parts directly in ice (frostbite), soak them in water (destroys remaining tissue), or scrub them with antiseptic. Time is ischemia, so prompt referral, consultation, and in-person surgical review are imperative.
How would you manage this injury?
As with any trauma, the initial evaluation of fingertip injuries includes assessing hemodynamic stability. Control active bleeding with direct pressure (or brief tourniquet if needed). The extent of amputation should be assessed, as this will determine management options. Hand dominance, mechanism of injury and vascular, neurological, and musculoskeletal status should all be evaluated and documented.
Analgesia – Providing adequate analgesia is of utmost importance, intranasal opioids and early ring block will be required as severe pain will continue to occur during assessment, cleaning, handling and management of the wound. Elevating the injured hand will also help to minimize swelling. This will help to reduce pain alongside immobiliation of the affected hand and wrist with a short splint.
The stump or affected digit in a partial amputation should be gently cleaned with saline. Minimal disruption of the tissues of the stump should occur if there is a potential for any tissue re-implantation). This should be done following a nerve block and it should have a dressing placed over it until more definitive management is possible. During this time antibiotics (as per local policy) should be given and tetanus status checked (and booster given if there is any uncertainty on status).
Imaging will be important to facilitate the specialist teams’ planning of the optimal management. The patient will need to have X-rays of the affected area of the hand. Three views – AP, lateral and oblique should be obtained. Ensure that any other injuries are looked for and investigated at the same time where possible (if this does not delay limb-saving treatment). Also be mindful that ongoing pain may occur and so top-ups and or escalation of initial analgesia may be required on return from X-ray and at other points during the patient journey. It is therefore important to undertake & document repeated pain score assessments at regular intervals.
Clinical Factors affecting management choice
(from EM News blog, teachmeanatomy, orthobullets)
The extent and location of the amputation will determine what treatment options are most appropriate. Although this will be the decision of the Hand surgery team as the emergency physician it is important to be able to clearly describe the injury during referrals and discussions with specialist teams so that delays to definitive management are minimised.
The fingertip can be divided into 3 (Allen) zones. Further zones are used to demarcate more proximal parts of the finger. These zones are helpful when fingertip amputations occur and can be used to classify the extent of the injury to the bone.
- Zone I Injuries: are distal to the bony phalanx. No bone is exposed. These can often be treated conservatively with frequent dressing changes over many weeks.
- Zone II injuries: are distal to the lunula of the nail and involve partial tuft fractures or bone exposure. These often need surgical intervention.
- Zone III injuries: the entire nail bed is lost (amputation is proximal to the distal end of the lunula). They involve the loss of bone and nail. These will almost always need surgical intervention to support wound healing, retain as much functionality as possible and for cosmetic purposes.
Treatment options
(from orthobullets, orthoinfo & the plasticsfella)
The decision on definitive treatment of any amputation mostly comes from the specialist plastics teams. However, as a paediatric emergency physician when discussing the patient journey with patients and their carers it is useful to have an understanding of the possible longer term management options
The goal of treatment is to have a pain-free fingertip that is covered by healthy skin and functions normally. Secondary goals include trying to preserve the length and appearance of the affected finger(s).
Although each case will be assessed there are some patterns of injury which will be likely to predict the required course of management. Aside from the zones affected, the angle of the fingertip injury/amputation also affects treatment choice.
____ Wounds made along the green lines will probably heal on their own.
____ Wounds made along blue lines will probably need some sort of surgery to heal.
Non-operative approaches
There is ongoing controversy regarding the best treatment of fingertip amputations, More extensive wounds are treated surgically. However, even in Allen III amputations, there is a lack of evidence to support enhanced healing and function of fingertips after surgical treatment compared to conservative management. Adults & children with zone 1 amputations (where no bone or tendon is exposed) and with < 2cm skin loss can often have their wounds managed conservatively with monitoring to ensure that the finger tip is healing appropriately by secondary intention. In young children even when the bone is exposed there may be times where conservative management can still lead to good outcomes due to their rapid cell turnover and associated healing ability.
Regarding fingertip amputations after animal bites, thorough surgical debridement is the preferred treatment due to various micro-organisms which may have contaminated the wound. Again there is no consensus about the primary closure of the wound. However, there is some emerging evidence that semi-occlusive dressing for treating fingertip amputations-only injuries may be effective.
Operative approaches
(from orthoinfo & the plasticsfella)
More extensive wounds (often zone 2 & 3) are treated surgically. Where the amputated fingertip tissue is still viable tissue replants may be feasible but this will be assessed on a case-by-case basis. In younger (often preschool age) children, if the patient has sustained multiple digit losses, salvage reimplantation is often attempted and the relative contraindications (severe crush injuries, multilevel amputations & prolonged detachment time & single digit proximal to the insertion of flexor digitorum superficialis) are ignored. More proximal amputations (beyond the fingertip) in adults are not often replanted. However, again in younger children with single-finger amputations after thoroughly cleaning fingers are often reattached to the finger stump. The fingertip may continue to grow relatively normally, even if bone was exposed. This is especially possible in children younger than 2 years of age.
Options for surgical management include primary closure (with removal of the exposed bone) following washout, full-thickness skin grafting taken from the hypothenar region & flap reconstruction.
A 15-year-old girl presented to ED at 23:30 on Tuesday night. She attended with her 15-year-old cousin and reported that they had been attacked by a group of girls whom she did not know. She reported that in self defense she had punched one of the attackers and accidentally hit a metal post they were near. She has since reported pain and swelling to her hand. Her X-rays are as follows.
What does the x-ray show?
How would you examine this patient?
How would you manage this patient?
What other considerations are necessary in this case?
Discussion
(From DFTB, reliasmedia & RCH)
What does the x-ray show?
The x-rays undertaken are AP, Lateral & oblique views. The x-ray shows a fracture through the neck of the fifth metacarpal with palmar angulation (Boxer’s Fracture).
Hand fractures are very common in children & young people. One study reported that up to 40% of these were attributable to metacarpal fractures. In general metacarpal fractures often occur whilst the child/ young person is undertaking sports activities.
Metacarpal fractures can be divided into fractures of the neck, head, shaft, and base. They however occur most commonly in the neck and are commonest in the 4th and 5th fingers (up to 80% of metacarpal fractures). A boxer’s fracture is the name given specifically to a fracture in the neck of the 5th (or 4th) Metacarpal. Commonly, the patient has punched something (or is hit by an object such as a sports bat while their fist is closed). When fractures occur in the metacarpal head (often also as a result of direct trauma). There is a high risk of joint involvement. These are at very high risk of late complications such as arthritis. It is therefore important that they can be correctly identified and referred early.
How would you examine this patient?
The child/adolescent will usually present with bruising, swelling and pain over the dorsum of the hand. Additional signs to look out for include loss of knuckle prominence and rotational deformity of the little finger. This can be looked for by asking the patient to make a fist. No degree of malrotation is acceptable. If present an orthopaedic/hand surgery team referral must be made.
How would you manage this patient?
Treatment is generally based on the level of injury (e.g. head, neck, shaft and base) and clinical findings (rotational deformities, open wounds, fracture stability). Simple nondisplaced and stable fractures of the neck or shaft of the 2nd – 5th fingers can often be treated conservatively. An ulnar gutter back slab should be applied and the patient referred for fracture follow-up. If there is any angulation in a neck of metacarpal fracture this will need a surgical review and treatment options will then depend on the degree of angulation. These however may include closed reduction in the emergency department with a nerve block and/or under procedural sedation. In some cases however, surgery will be required. This is especially if there are any open wounds, suspected tendon injuries or significant angulation/rotational deformity.
What other considerations are necessary in this case?
Ensure that the skin overlying the fracture has been checked. Substantial skin wounds may need surgical wash out and patients with “fight bites” will also need antibiotics. Tetanus status must also be checked and vaccine given when there is doubt in status. It is also important to check that the flexor/ extensor wounds near any injury are not affected.
Safety Advice:
A child/adolescent who presents to paediatric ED with a hand injury because of a fight or an injury mechanism such as punching a wall requires special attention. This includes screening for mental health and/or social problems. In this particular case there are safeguarding concerns in relation to the time of day of presentation without parents/ carers being in attendance. Screening tools such as the HEEADSSS assessment can help to direct questions. Consideration and also time to gain rapport to sensitively discuss any potential gang violence, domestic violence or associated concerns in relation to child exploitation should also be given. Involvement of medical social worker teams or mental health teams may be necessary. Additionally where available locally Youth violence/ youth worker teams should be involved.
A 12-year-old child had been helping their grandfather with some DIY at home and whilst hammering a nail tac into some wood accidentally hit themself. They presented to the emergency department crying with an extremely sore thumb. At triage they were sent for x-rays and you were asked to see them on their return.
- What is the diagnosis?
- What analgesia would be most appropriate?
- How would you manage this injury? And when would you refer?
- Would you give any other medications (antibiotics)?
Discussion points:
(from DFTB, Orthobullets, EM News Blog, Royal Children’s Hospital Melbourne)
What is the diagnosis?
The image shows a subungual haematoma. The x-ray additionally confirms that there is an underlying tuft fracture.
This injury is a type of nail bed injury. These types of injury can vary in severity and range from subungual haematomas to nailbed avulsions. A nail bed injury refers to damage to the soft tissue underneath the nail plate. This includes injury to the nail bed and/or the germinal matrix.
Subungal haematomas are often caused by a blow to the fingertip. This then leads to bleeding under the nail. They can be incredibly painful. To unsuspecting patients and carers they can also be very scary to look at.
Subungual haematomas are fairly commonly seen in the paediatric emergency department. They are commonly caused by a direct blow to the finger. It is therefore not surprising that children/young people often sustain these injuries through accidents during play such as objects falling onto fingers (and similarly toes) or via accidents occurring around everyday activities such as accidental entrapment of fingers in car/ fire doors.
In a subungual haematoma the bleeding may be confined to only a small part of the nail. It however could extend to include the area under the whole nail plate. As blood accumulates in this closed compartment so does the pressure. This then causes immense pain. If there is a nail bed injury an x-ray of the affected finger is required. This is to check if there is an associated bony fracture (most commonly of the distal phalanx).
What analgesia would be most appropriate?
The child/young person will have already gone through a distressing event to have ended up with a subungual haematoma. Calming down the child through parental support and/or distraction including the support of play specialists will be vital in enabling you to comprehensively assess a child and manage them appropriately.
In relation to the subungual haematoma some relief will occur if it is evacuated however there is potentially still & underlying fracture and or surrounding soft tissue injury which will also be a source of pain. Analgesia must always be given and consideration of the need for escalation depending on the level of treatment that is required.
Type of pain relief/ Management options
Simple analgesia (paracetamol/Ibuprofen) | Should be offered to every patient as minimum unless there is a medical contraindication |
Intranasal opioid | Useful in very distressed children, if multiple digit involvement, associated fractures or large open wounds |
Ring block | Useful if associated fractures or large open wounds, or very dirty wounds requiring thorough washout, or management under plastic |
Entonox | May be suitable in a child old enough (usually > 5 yrs) can hold mouth piece and co-ordinate breathing |
Procedural sedation | Useful if associated fractures or large open, or very dirty wounds requiring thorough washout, or management under plastics |
Despite maximal analgesia in ED sometimes the only way of really examining the wound to establish if there is an associated nail bed laceration is using a general anaesthetic. This may also be necessary in younger children when distraction is not possible and or in cases with more significant and other associated injuries where procedural sedation is contraindicated or not available in the department. Once in theatres (especially if the subungual haematoma covers > 50% of the area under the nail plate) the wound is cleaned and often the nail lifted up or removed.
How would you manage this injury? And when would you refer?
The ultimate goal is to drain the accumulated blood and relieve the painful pressure. Simple first aid measures are helpful in terms of management including putting direct pressure on wounds to help control ongoing bleeding. Other measures such as elevation helps with pain reduction and associated swelling. Using a cold compress may also provide some additional relief. It is easy to see the injured nail and focus all attention here. It is however still important to check that no other structures of the hand are affected especially in smaller children who may not be able to describe pain in other areas especially if they have a distracting injury.
Trephining a subungual haematoma
Although treatment options may vary locally. There is a general consensus that if the haematoma involves less than 50% of the visible nail then simple techniques can be used in ED to relieve the pressure (trephining). Some departments have specific cauterising devices. Alternatively drilling slowly with a green needle can also relieve the pressure. It is important to note that PPE must be worn as the blood may squirt out of the opening in the nail plate as the high pressure is released. It is also important to note that in order for the procedure to be successful the blood must be fresh. After a maximum of around 48 hours the trapped blood may become too congealed to flow out of the small opening created. If more than 50% of the nail bed is involved then it may be necessary to lift up the nail to evacuate the haematoma. This requires a surgical referral as to patients who present with other injuries such as associated large lacerations and or nail bed avulsions.
Here is a video from don’t forget the bubbles which will help to show you how it’s done:
The heat is on: trephining a nail to release a subungual haematoma
If there is an associated nail bed avulsion even if the nail plate looks very loose; do not be tempted to remove it. If necessary this should be done by the plastics team. It can take six to twelve weeks for the nail to regrow and if the germinal matrix is damaged it may become either ridged or deformed. The partially attached nail often provides the best protection for the underlying finger tip so don’t remove it.
When there is substantive injury and may involve nail plate fixation may be done via suturing the nail plate to the bed. This allows the nail plate to be anchored to the nail bed to provide protection and encourage better new nail growth. In these cases sutures may be required to stay in place for 10-14 days. However there is emerging evidence that cryoacrylates (Adhesives) may be as effective as suturing for fixation purposes. An alternative management approach is open (surgical) reduction and nail bed repair may be needed. Surgical repair can also be an option to improve the cosmetic appearance of the new nail growing through. In these situations the nail is removed, and the laceration repaired with absorbable sutures. Following this type of nail bed repair, it can take around 6 months for the new nail to fully grow through and the finger can be sensitive to cold during this time.Simple subungual haematomas that have been trephined do not need any further dressings applied. However in more complex injuries or those that have required surgical management finger dressings are important. A non adhesive dressing should be first applied to the wound to minimise the risk of new trauma occurring during dressing changes/removal. A finger tip protector can be made with either an aluminium splint or with the simple plastic fake finger tips. Injuries treated conservatively should heal on their own in two to three weeks.
What to do with the broken bone?
In this particular case in the finger with the subungual haematoma there was a tuft fracture at the distal tip of the distal phalanx. This requires no further management in relation to the fracture. However it is imperative that a child presenting with a similar clinical picture that X-rays are carefully reviewed to ensure that there is not a Seymour’s fracture.
A Seymour fracture is an injury unique to children. This fracture pattern is usually caused by a crush injury. The resultant injury is an angulated Salter-Harris type I or type II fracture with an associated nail bed injury.
In contrast to adult bones, children’s bones are still developing. They have cartilaginous discs which separate the epiphysis from the metaphysis of long bone. This area is called the growth plate (physis).
Physeal fractures are classified by the Salter-Harris classification. A Type II fracture is the most common type.
In relation to a Seymour’s fracture it is important to recognise this fracture pattern early as referral to a hand surgeon is important to avoid complications. Possible complications include osteomyelitis, malunion, and pre-closure of the physis. Treatment may be conservative – especially in closed injuries which are managed with closed reduction and splinting. Operative management may however be required with open (surgical) reduction.
Would you give any other medications (antibiotics)?
Antibiotics; To give or not to give, that is the question.
Current evidence supports the stance that Isolated tuft fractures do not require a course of prophylactic antibiotics especially when adequate wound cleaning has occurred. They do not improve outcomes. A BestBets evidence review in 2011 looked at 4 published papers between 1948 & 2011. This included over 500 cases in total. It attempted to answer whether patients with compound fractures of the distal phalanges needed antibiotics to prevent osteomyelitis. The conclusion was that Antibiotics are not indicated if appropriate initial wound management takes place. There is no clear evidence that use of antibiotics has a significant effect on reducing overall infection rates.
Some clinicians still advocate for prescribing antibiotics to children, especially heavily contaminated nail bed injuries. However, most agree that antibiotics are not needed if trephining the nail with no nail bed laceration. In all patients, tetanus status must be checked and boosters should be given if there is uncertainty to the patients’ vaccine status.
A 12-year-old child presented to ED with a painful finger whilst tackling another player in a rugby lesson at school. She complained of pain in her right ring finger and was unable to move it. An x-ray was done but no fracture was seen. There was swelling and she reported tenderness along the palm side of the numbness at the finger fingertip, which looks a little blue.
- What anatomical structures are you concerned may be damaged?
- How would you assess this child? (this can be discussed or role-played)
- How would you manage this patient?
Discussion
(RCEMlearning, BSSH, PEMinfographics, DFTB, ASSH, orthoinfo)
What anatomical structures are you concerned may be damaged?
Many times when there are no overt fractures on an x-ray we conclude that the patient has a “soft tissue” injury or sprain. Even when bony pathology cannot be identified on x-rays it is important to consider if there is damage to the muscles, ligaments and tendons of the hand. It can have a significant impact on a child’s ability to undertake daily activities especially if the injury is to their dominant hand. It is therefore important to be confident in being able to examine the hands and ascertain when significant soft tissue injury has occurred which needs further management. As with any injury presenting to the emergency department, pain should also always be assessed and managed.
In this case the history would suggest that there is potential for an injury to the flexors of this finger (namely flexor digitorum profundus). This is an injury that often occurs following sudden hyperextension of an actively flexed finger (such as grabbing a top/jersey during sporting activities). It is therefore known as a Jersey, sweater or rugby finger. There is an avulsion of the flexor digitorum profundus (FDP) from the volar base of the distal phalanx base. It most commonly affects the 4th digit. This is because the FDP insertion into the ring finger is anatomically weaker than that of the middle finger (and these two digits are the ones used mostly when trying to grip a moving object).
How would you assess this child? (this can be discussed or role played)
In the earlier part of this module we looked at methods of assessing the hand. The approach of look, listen & feel should always be undertaken. (see section 1 for a step by step approach to hand examinations).
It is important to try and examine the hand in the position it was in during the injury in order to assess that part of the tendons affected.
Look – for any deformity, swelling, bruising, colour change or overlying lacerations
Feel – Asses for any bony tenderness, remember to assess for any signs of neurovascular compromise and check sensation in the forearm and hand.
Move – Making tasks quick and easy to reproduce will assist in making identification of pathologies easier when assessing children. Don’t forget to use the scissors, paper, rock, ok manoeuvres to help you quickly do a screening check of the integrity of parts of the key nerve and muscle groups of the hand (and wrist).
There are lots of soft tissue structures in the hand. We have earlier described some of the functions of the intrinsic and extrinsic muscles of the hand. When examining it is also important to carefully isolate & examine the tendons. As the forearm is compressed, the digits are drawn into flexion. The digits also extend and flex when passively moving the hand and wrist through flexion and extension. There are a number of special tests which are therefore useful to help identify the specific structures in the hand that have been affected following an injury. Testing should be undertaken under resistance as active function can still be maintained with even up to 90% of a tendon being lacerated/disrupted.
Tendon Evaluation Tests
(from RCEM learning)
Testing the Flexor Tendons:
Flexor digitorum superficialis (FDS)
Hold fingers not being tested in full extension (inactivating deep flexors). The patient should then bend the affected finger. The DIPJ should be flaccid. N.B: The index finger has a separate muscle belly so in order to isolate this FDS – keep DIPJ extended & check resisted PIPJ flexion.
Flexor digitorum profundus (FDP)
If the PIPJ is held in extension this isolates the FDS. The patient should then be asked to flex the tip of the finger.
Flexor pollicis longus (FPL)
When holding the thumb over the proximal phalanx the patient should try to bend the tip.
Testing the Extensor Tendons:
Long extensors of the hand
The fingers should be straightened against resistance. The long extensors straighten at the MCPJ, and resistance should be applied to the dorsum of the proximal phalanx.
Extension at the PIPJ can be caused by the intrinsic muscles. Observe for loss of active extension at the DIPJ, i.e. a mallet deformity.
Extensor pollicis longus (EPL)
With the patients hand palm-down on a table, ask the patient to lift up their thumb, against resistance.
How would you manage this patient?
When there is a suspected flexor tendon injury for description purposes (referral and documentation) it is useful to describe the location of injury in regards to zones of the hand. A Jersey injury is a zone 1 injury.
Flexor tendon injury classifications
- FDP only
- Insertion of FDS and edge of palmar crease
- Palmar proximal end of 1st annular pulley – distal edge of carpal tunnel
- Carpal tunnel
- Proximal to the carpal tunnel
Management of flexor tendon injuries often involves early surgical repair of flexor tendon disruption. This is then followed by a postoperative passive-motion rehabilitation programme.
Non-operative approaches: Tendons cannot heal unless the ends are touching. In most cases, a cut or torn tendon must be repaired surgically. It however may be possible if there is an injury which has only caused a partial tear to manage it conservatively. In such a case splints would be used to protect the hand. In a level 1 injury a specialised finger splint/orthosis may be required. For an injury in zone 2 or above larger splints +/- plaster casting will be required. The splints are always on the dorsal side. This is so that the area is held in flexion so that there is no extra strain on the repaired tendon.
Operative management: Following a Jersey injury, surgery will be required. The vast majority of flexor tendon injuries will need surgical intervention. Most will require suturing back into place or potentially bone fixation where avulsions have occurred. Following this there will need to be an ongoing process of healing followed by rehabilitation. Following surgery the hand and fingers may be placed in a splint/cast with the fingers and wrists in a bent position. This is usually required for 6-8 weeks following surgery. This is to reduce any tension around the repair site. Physiotherapy input will then be required in order to support a number of exercises aiming to bring back function to the affected areas. Overall, a flexor tendon injury takes approximately 3 to 4 months in total to heal before the hand is strong enough to use without restrictions.
Though specific designs will vary by location, below are some examples of the types of splints that may be used following a flexor tendon injury.
Dorsal blocking orthosis (Kleinert Protocol)
The Kleinert protocol was established to incorporate a dynamic pull on the involved finger(s) to avoid tension on the sutured tendon. An elastic thread/rubber band is attached to the involved finger. This rubber band pulls the involved finger(s) into complete PIPJ and DIPJ flexion and attaches to the volar forearm or a volar placed strap. It can be adjusted to help with exercises
Dorsal Based orthosis (Manchester Protocol)
Splints like this may be used following surgical repair of flexor tendon injuries in Zone 2. It allows maximal wrist flexion and blocks Metacarpophalangeal joint extension at 30 degrees.
Wounds: When lacerations/open hand wounds have caused injury to the hand, careful clinical evaluation of the integrity of the tendons, nerves and vascular functions in the affected area is needed.
Any deep wound that breaches the deep fascia or palmar aponeurosis needs formal surgical exploration.
Long-term outcomes:
Generally patients have good outcomes following interventions. However, flexor tendon injuries can be very challenging to treat. Some patients may still develop stiffness and poor function (permanent loss of flexion at the DIPJ) of a digit even after flexor tendon injury and repair. This will be especially problematic if in the dominant hand of a child. Sometimes after a flexor tendon repair surgery, scar tissue forms and this may cause the tendon to stick to the tendon sheath. Initially physiotherapy is used to try to improve this. However if it does not improve a surgical release (tenolysis) may then be required. This surgery can only be performed once the initial repair has healed (4-6 months post initial repair), adding to the overall healing time. It is therefore really important to identify when tendon injury has occurred and ensure that a prompt hand surgery team review occurs so that the correct management plan can be made.
Depending on the experience of the learners in your group please choose and adapt the following practical elements:
- Role-play hand examinations in pairs. Identifying techniques to follow and signs to exclude. Can be done in OSCE format.
- Trephining – demonstration by facilitator techniques to trephine subungual haematoma. Technique dependent on what devices are available in your department. Alternatively videos from below could be used prior to a learner practice session: The heat is on DFTB – Youtube
- Splint, bandages and/or Plaster of Paris hard cast application- specifically volar splints and finger splinting demonstration by facilitators or alternatively videos from below:
- Ulnar gutter Backslab: https://www.youtube.com/watch?v=DBmm8wQw2PQ
- Volar Backslab: https://www.youtube.com/results?search_query=volar+splint
- Finger Dressing: https://www.youtube.com/watch?v=23H6Cq6icXU
Question 1
Which of the following is true?
A: In a subungual haematoma a course of antibiotics is often required if there is a tuft fracture
B: The nail growth comes from the germinal matrix of the nail bed
C: A Seymour’s fracture is a fracture of the mid shaft of the distal phalanx associated with a subungual haematoma
D: Zone 3 fingertip amputations are often treated conservatively in young children
Answer 1
The correct answer is B.
In relation to the anatomy of the nail unit, nail growth arises from the germinal matrix. If the injury to a fingertip affects this area further nail growth is likely to occur and a surgical opinion should be sought. In a child with a subungual haematoma and tuft fracture there has been no clear evidence of proven benefit in giving a prophylactic course of antibiotics to prevent infection. They are therefore rarely indicted. A Seymour’s fracture is associated with a subungual haematoma. However the fracture is a salter-harris 1 or 2 fracture of the distal phalanx. Finally, zone 1 fingertip amputations may sometimes be treated conservatively, however zone 2 and 3 in children often are treated surgically with a replant in young children (in contrast to adults). Therefore keeping any tip bought along by parents/ carers in good condition is important.
Question 2
Which tendon/tendons will be affected in a Jersey finger injury?
A: Flexor digitorum superficialis
B: Extensor digitorum
C: Flexor digitorum profundus
D: All of the above
Answer 2
The correct answer is C.
A jersey injury affects the ability of a person to flex the distal interphalangeal joint (tip of finger). It can also help to flex the proximal interphalangeal joints, however this is also done by the flexor digitorum superficialis (hence there is primarily tip function loss). It occurs following sudden hyperextension of an actively flexed finger (such as grabbing a top/jersey during sporting activities). There is an avulsion of the flexor digitorum profundus (FDP) from the volar base of the distal phalanx base. This is not always visible on X-ray. It most commonly affects the 4th digit. The extensor digitorum extends the metacarpophalangeal joints.
Question 3
Which statement is false?
A: The radial nerve facilitates active flexion of the thumb
B: An ulnar nerve disruption will affect finger strength (adduction/abduction)
C: The median nerve may be affected following a wrist injury
D: The radial nerve facilitates thumb extension
Answer 3
The correct answer is A.
It is in fact the median nerve that facilitates active flexion of the thumb. All of the other statements are true. To recap the innervations of the muscles of the hand see tables 1, 2 and 3. Here is also a screening overview.
- https://litfl.com/bscc/clinical-anatomy/hand-anatomy/ video series on hand and wrist injuries
- https://teachmeanatomy.info/upper-limb/bones/bones-of-the-hand-carpals-metacarpals-and-phalanges/
- https://teachmeanatomy.info/upper-limb/muscles/hand/
- https://teachmeanatomy.info/upper-limb/misc/flexor-system-hand/
- The Carpal Tunnel – Borders – Contents – TeachMeAnatomy
- https://doi.org/10.53347/rID-66814
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- https://teachmeanatomy.info/upper-limb/joints/wrist-joint/
- https://teachmeanatomy.info/upper-limb/vessels/arteries/
- https://teachmeanatomy.info/upper-limb/muscles/posterior-forearm/
- https://teachmeanatomy.info/upper-limb/muscles/anterior-forearm/
- https://radiopaedia.org/articles/intrinsic-muscles-of-the-hand?lang=gb
- Intrinsic muscles of the hand (mnemonic) | Radiology Reference Article | Radiopaedia.org
- https://www.bssh.ac.uk/patients/conditions/27/extensor_tendon_injury#What_are_the_extensor_tendons_
- https://www.bssh.ac.uk/patients/conditions/26/flexor_tendon_injury
- https://www.rcemlearning.co.uk/reference/soft-tissue-injuries-of-the-hand/#1583314726481-cfe0feb0-a6b8
- https://www.orthobullets.com/hand/6007/blood-supply-to-hand
- https://www.nysora.com/techniques/upper-extremity/wrist/wrist-block/
- https://teachmeanatomy.info/upper-limb/misc/nail-unit/
- https://geekymedics.com/hand-examination/
- https://dontforgetthebubbles.com/finger-tips/
- https://www.cureus.com/articles/63084-nail-regeneration-of-an-allen-iii-fingertip-amputation-after-a-dog-bite-using-the-semi-occlusive-dressing-technique-a-case-report-and-literature-review
- http://www.emdocs.net/evidence-based-approach-to-nailbed-injuries-ed-presentations-evaluation-and-management/
- Nail Bed Injury – Hand – Orthobullets
- https://www.youtube.com/watch?v=YWxawOCt2rs
- https://www.reliasmedia.com/articles/115717-pediatric-hand-injuries-part-ii-lacerations-amputations-bites-and-nail-bed-injuries
- BestBets: The Role of Prophylactic Antibiotics in Compound Fractures of the Distal Phalanges of the Hand
- https://journals.lww.com/em-news/blog/theproceduralpause/pages/post.aspx?PostID=99
- https://orthoinfo.aaos.org/en/diseases–conditions/fingertip-injuries-and-amputations
- https://www.reliasmedia.com/articles/114255-pediatric-hand-injuries-part-i-fractures-and-dislocations
- https://www.rch.org.au/uploadedFiles/Main/Content/hand-therapy/paediatric_hand_trauma_fractures.pdf
- https://www.assh.org/handcare/condition/boxers-fracture
- https://radiopaedia.org/cases/boxer-fracture-3
- Clinical Practice Guidelines : Phalangeal Finger Fractures (rch.org.au)
- https://www.rch.org.au/fracture-education/growth_plate_injuries/Physeal_growth_plate_injuries/
- https://www.rch.org.au/clinicalguide/guideline_index/fractures/Distal_radius_and_or_ulna_metaphyseal_fractures_Emergency_Department_setting
- https://www.peminfographics.com/infographics/rock-paper-scissors-ok
- https://litfl.com/bscc/clinical-anatomy/hand-and-wrist-injuries/
- http://www.emdocs.net/hand-expedited-examination-key-points-regarding-ed-diagnoses/
- https://www.rcemlearning.co.uk/reference/soft-tissue-injuries-of-the-hand/#1583314726481-cfe0feb0-a6b8
- https://orthoinfo.aaos.org/en/diseases–conditions/flexor-tendon-injuries/
- https://www.orfit.com/blog/dorsal-blocking-orthosis-for-flexor-tendon-rehabilitation/
- https://www.youtube.com/results?search_query=volar+splint
- https://www.youtube.com/watch?v=23H6Cq6icXU
- https://functionalanatomyofthehand.wordpress.com/2016/04/14/anatomy-of-the-hand-3/fds/
- https://www.bsuh.nhs.uk/library/wp-content/uploads/sites/8/2020/06/Paediatric-guidelines-hand-injuries-2019-2.pdf
- Georgoulis D J, Melissaridou D, Zafeiris I, et al. (August 10, 2021) Nail Regeneration of an Allen III Fingertip Amputation After a Dog Bite Using the Semi-occlusive Dressing Technique: A Case Report and Literature Review. Cureus 13(8): e17068. doi:10.7759/cureus.17068