Phalangeal fractures and dislocations
Introduction
Hand fractures and Phalangeal fractures and dislocations are one of the most common injuries and its incidence continues to rise. Hand fractures can be complicated by deformity from no treatment, stiffness from overtreatment, and both deformity and stiffness from poor treatment.This chapter aims to provide a simple guide for primary care health professionals on management of finger fractures.
Terminology
Tuft fracture: Fracture involving the tip of the distal phalanx usually due to crushing injury, often associated with lacerations of the nail matrix or pulp.
Seymour fracture: Epiphyseal fracture of the distal phalanx characterised by apex dorsal angul
ation, and often associated with transverse laceration of the nail matrix and avulsion of the nail plate superficial to the proximal nail fold.
Pilon fracture: Intraarticular fracture involving the PIPJ with comminution and splaying of the base of the middle phalanx.
POSI: Position of safe immobilisation. Also called intrinsic-plus or Edinburgh position. The wrist is in 0-30⁰ extension, MCPJ 70-90⁰ flexion, and IPJ in full extension.
History
Age: paediatric fractures are treated differently and more conservatively. Amputated fingertips can be sutured back as a composite graft in paediatrics in the acute setting.
Occupation: Treatment should be tailored to the needs of certain groups of patients such as manual laborers, and musicians.
Mechanism of injury: High energy trauma can result in comminuted fractures with significant soft tissue injury.
Twisting injuries results in spiral fractures.
Contaminated open fractures such as sewage, marine or animal / human bite injuries are surgical emergencies.
Smoking: is detrimental to fracture healing and should be stopped.
Hand examination:
Look
- Skin:
- Erythema: may indicate local inflammation or infection.
- Lacerations: may indicate open fractures. Nail bed injuries and subungual haematoma (comment on the degree whether less than or more than 50%) may indicate tuft fractures.
- Hand cascade: loss indicate tendon injury
- Deformities
- Malrotation: presents with finger scissoring (finger is crossing over the adjacent finger) on finger flexion (fig.1). If patient is unable to flex, observe the position of the nail plate compared to normal fingers. More common with oblique and spiral fractures.
- Angulation: More common with transverse fractures.
- Depressed or sunken knuckles in cases of metacarpal head or neck fractures.
Feel
After documenting the neurovascular status of the fingers and hand, local anaesthetic can be administered to facilitate the rest of the palpation.
- Neurovascular status:
- Capillary refill time (normal 2-3 seconds).
- Sensation on either side of each finger using light touch and comparing to the same finger on the other hand, sensation can be scaled from 0-10.
- Palpation
- Phalanges, metacarpal, and carpal bones for tenderness, bony spikes
- Over the tendon sheath for tenderness
- Raised temperature may indicate bone or soft tissue infection.
- Joints stability: Stress test for volar plate. lateral stress test for collateral ligament integrity. Ligamentous injury can be classified into
- Grade I pain with no laxity.
- Grade II: some laxity and there is a firm endpoint.
- Grade III: gross laxity and no firm endpoint.8
Move
- Active movement
- Assess all range of movements of each joint.
- Scan for nerve injury: O sign to test for anterior interosseus nerve function, Thumb extension to test radial nerve function, and star sign with abduction of fingers to test for ulnar nerve function.
- Passive movement: useful in observing any deformity and identifying the limitation of function which could be due to soft tissue injury or a fracture.
Fig.1 shows scissoring of the little finger under the ring finger due to a spiral fracture of the proximal phalanx of the little finger
Investigation
Bloods
- WCC and CRP, lactate if suspecting infection or sepsis, clinical exam is more appropriate as can be normal in 75% of cases.
XR
- At least 2 views; posteroanterior and true lateral for phalangeal fractures. For metacarpal and complex articular fractures, an additional oblique view should be performed.
- Other special views are:
- The Brewerton view shows collateral avulsion fractures of the metacarpal head.
- A skyline metacarpal view is useful in clenched-fist injuries as it shows the dorsal articular surface of the MCPJ.
- CT scans can be used for preoperative planning of articular fractures and carpal bone dislocations and fractures.
Indication for surgery in phalangeal and metacarpal fractures
- Unstable fractures:
- All Irreducible Fractures
- Spiral and short oblique fractures are at high risk of displacement.
- Presence of Deformity with Malrotation, angulation, shortening, especially with failed closed reduction.
- Specific fractures: displaced articular and subcapital phalangeal fractures.
- Open fractures, associated soft tissue injury and Segmental bone loss
- Multiple injuries:
- Polytrauma with hand fractures.
- Multiple hand or wrist fractures.
Metacarpal Fractures
Case
25 year old patient comes to your clinic after punching a wall in anger. He has a grossly swollen hand with bruising and scissoring of middle finger under ring finger when he makes a fist.
Metacarpal neck fracture
Usually involves the little and ring fingers metacarpals and are called Boxer’s fractures although they rarely occur in professional boxers. Most of those closed fractures are treated nonoperatively.
The little finger tolerates higher degrees of angulation (up to 70 degrees) due to the CMC movement in contrast to the index and middle fingers which have a low tolerance to angulation (10-15 degrees).13
Management
Non operative:
- Closed reduction can be achieved using Jahss maneuver of reduction by flexing the MCPJ into 90 degrees this allows the proximal phalanx to be used to apply upward pressure on the metacarpal head and help in reduction while counter pressure on the metacarpal shaft is applied downward as shown in fig.2.16
- A Dorsal forearm ulnar gutter splint for the little and middle fingers where the wrist is 30 degrees dorsiflexed and MCPJ is 70 degrees flexed. Referral to physio therapy or hand therapy important for rehab.
Operative:
- Open fracture
- Rotation or scissoring of fingers due to malalignment and if there is pseudoclawing (MCPJ hyperextension and PIPJ flexion) that affects the function.
- Unacceptable degree of displacement
Fig.2 Jahss maneuver for reduction of metacarpal neck fractures. (A) The arrows show the direction of applied pressure. (B) shows the ulnar gutter splint post-reduction.13
Metacarpal shaft fracture
- Classified into transverse, oblique, and comminuted.
- In spiral or oblique fractures, a minimal degree as low as 5 degrees can lead to a 1.5 cm overlap between fingers. This should be assessed clinically as it is hard to assess on radiographs.17
- Most metacarpal fractures are managed non-operatively.
Non operative management: immobilization in a plaster splint for 3 weeks (splint is removed once there is no tenderness)
Indication for surgery is as explained above (open fracture, unstable, multiple fractures or rotation deformity): K-wire fixation or ORIF
Phalangeal fractures
Distal phalangeal fracture classification:5
- Tuft (simple – comminuted)
- Shaft (transverse – longitudinal – stable – unstable)
- Articular fractures (volar – dorsal – epiphyseal)
Tuft fractures
Fracture involving the tip of the distal phalanx, usually due to crushing injury (Fig 3). Tuft fracture should be assessed for pattern (simple or comminuted), closed or open (associated subungual hematoma, lacerations of the nail matrix or pulp, fig 4).
Comminuted tuft fractures rarely require internal fixation. These fractures often fail to unite but are stabilized by a fibrous union.
Fig.3 Tuft fracture
Fig.4 open tuft fracture with nail bed / pulp laceration
Algorithm of management
* Splinting is continued for 10-14 days for symptomatic relief
** Nail trephination can be achieved by a small drill bit, heated paper clip, or electrocautery. Trephination theoretically turns a closed fracture into an open one which warrants antibiotics intake.
*** Surgical repair involves repair of pulp lacerations and nail matrix and replacing the nail plate as a splint.
Shaft fractures of distal phalanx
Shaft fracture should be assessed for pattern (transverse or longitudinal fig. 5), displacement, and whether open or closed.
Fig.5 Longitudinal shaft distal phalanx fracture
Management
- Nondisplaced closed fractures: splinting for 10-14 days for symptomatic relief
- Displaced / unstable transverse closed fracture: Fixation with axial K-wire.
- Displaced / unstable transverse open fracture: Fixation with longitudinal K wire and soft tissue repair.
Epiphyseal fracture of distal phalanx (Seymour fracture)
Apex dorsal angulated physeal fracture in children, commonly with transverse nail matrix laceration and avulsed proximal nail plate superficial to the proximal nail fold, especially in
children. It occurs mainly due to hyperflexion injury. It can present as open mallet injury and can be mistaken for DIPj dislocation.
Management: Surgical: removal of nail plate, washout, fracture reduction, repair of nail matrix, replacing the nail to act as a splint. Postoperative splinting is required usually for 2 weeks, keeping the distal fragment in extension.
Avulsion fractures of the volar lip of the base of the distal phalanx (Jersey finger) (fig7)
Common in contact sports due to the extension of the DIP during maximal flexion.
Avulsion of the flexor digitorum profundus is classified by Leddy and Packer26
- Type I avulsion of the FDP into the palm needs urgent surgical repair as the tendon loses the binocular blood supply.
- Type II avulsion of the FDP into PIP joint. Sometimes a primary repair can still be done up to 6 weeks as part of the vincular blood supply is still intact.
- Type III avulsion fracture of the FDP into the distal end of the A4 pulley with a large bone fragment. This requires surgical repair with k-wire or screw fixation.
- Type IV27 fracture and avulsion where there is avulsion of the tendon from the fractured fragment. The proximal stump may retract to the palm or stays in the flexor sheath. This type needs US or MRI to diagnose. Treated by fixing the fracture first and then suturing the tendon into the distal phalanx.
Pull-out suture of the tendon over a dorsal button is used to fix the tendon as there is no distal tendon stump to suture.
All avulsion fractures should be treated early as it is difficult to predict the retraction level of the FDP proximal stump. Advanced imaging aids to detect the level of proximal tendon retraction.
Fig.7 Avulsion fracture of the volar base of the distal phalanx of the thumb
Fractures of the middle and proximal phalanges
Classification
- Articular fractures of the phalanges
- Condylar
- Other phalangeal head fractures
- Phalangeal base fractures
- Non-articular fractures of the phalanges
- Neck fractures
- Shaft fractures
Condylar fractures
Classification:
- Type I: Stable fractures without displacement
- Type II: Unicondylar, unstable fractures.
- Type III: Bicondylar or comminuted fractures (Fig.8)
Even with initially nondisplaced, condylar fractures are inherently unstable.6
Fig.8 Bicondylar displaced fracture head of proximal phalanx
Management
- Non-operative: splinting and very close follow up due to high risk of displacement.
- Operative:
- Multiple k-wires: Provides best final range of motion.
- Lag screws (Fig.9)
Minicondylar plates
Fig.9 Fixation with 2 lag screws
Other phalangeal head fractures Collateral ligament avulsion fractures of head of proximal phalanx
Management: test for lateral stability
- Stable: conservative management with splinting and hand therapy for early mobilisation.
- Unstable: ORIF (depending on fragment size) / ligament reconstruction.
Extensively comminuted head fractures
Management include ORIF vs conservative treatment. Management is individualised per case.
Phalangeal base fractures
Avulsion fractures
- Dorsal base of middle phalanx: Caused by avulsion of central slip with extensor lag. Can be associated with anterior PIPJ dislocation. Boutonniere deformity can occur if untreated.
- Lateral volar base of middle and proximal phalanges: Caused by collateral ligament avulsion (Fig.10)
Fig.10 collateral ligament avulsion fracture base of P2
Management
Assess size of the fragment, degree of displacement and joint stability.
- Minimally displaced fractures with stable joint: conservative management with splinting and hand therapy for early mobilisation
- Significantly displaced fractures > 2mm and joint instability: ORIF
Comminuted Pilon base fractures
Axial load on the joint that causes central articular depression and splay of articular margins (fig.11).
Fig.11 Pilon fracture base of P2
Management
- Splinting
- Traction across the joint
- ORIF +/- Hemihamate reconstruction.
Splinting causes more severe stiffness. Traction and ORIF have similar results. Regardless of
the treatment, significant articular remodelling occurs over time.
Shaft fractures involving the joint
A long spiral fracture of the proximal (and sometimes middle) phalanx may project into the retrocondylar space of the IP joint and can be a mechanical block to flexion (fig.12).
Fig.12 Displaced long spiral fracture blocking PIPj flexion.
Management
- ORIF is usually necessary.
- In unreduced healed with a residual spike: can be removed to improve flexion.
Non-articular fractures of the phalanges
Neck fractures
More common in toddlers than adults. Can be best diagnosed on true lateral views. The head fragment lacks tendon attachment therefore can easily displace dorsally and rotate up to 90 degrees with articular cartilage pointing dorsally.
Classification7
- Type I: non-displaced
- Type II: Displaced with some bone-to-bone contact.
- Type III: Displaced with no bone-to-bone contact.
Management
- Non-displaced fractures: splinting.
- Displaced fractures
- Closed reduction and splinting
- Closed reduction and K wires
- ORIF
Shaft fractures
Fracture pattern:
- Transverse: More common with middle phalanx. Most common deformity is angulation.
- Oblique / spiral: More common with proximal phalanx. Most common deformity is rotation and shortening (fig13)
- Comminuted: Most common deformity is shortening (fig.14)
Fig.13 Shaft oblique displaced fracture.
In proximal phalanx it is usually apex volar angulated due to strong interossei muscle insertion. It is variable with middle phalanx
Fig.14 Comminuted fracture of middle phalanx of right ring finger
Management
Open fractures: will require surgical washout, ORIF and soft tissue repair / reconstruction.
Closed fractures: Assess stability and fracture pattern. Unstable fractures include those prone to deformity, oblique / spiral / comminuted patterns, and failure to maintain initial closed reduction.
- Non-displaced stable fractures: Splinting in POSI for 3 weeks followed by mobilisation with buddy taping for 2 weeks
- Displaced fracture but stable after reduction: Splinting in POSI for 3 weeks, with buddy taping of adjacent fingers. This is followed by mobilisation with buddy taping for 2 weeks.
- Displaced unstable fractures: closed reduction (open if closed failed) and fixation.
Dislocations
MP joint dislocation18
- Dorsal dislocations are due to hyperextension, they are rare and mostly affect the index and little fingers.
- Classified into simple which reduces easily or complex dislocation that has soft tissue interposition mostly volar plate between the metacarpal head and the proximal phalanx. Rarely the metacarpal head projects between the flexor tendons and the lumbricals. This is called Kaplan’s lesion and usually requires open reduction and release of A1 Pulley to release the tension.
- For closed and stable dislocations post reduction: early active movement as tolerated with buddy strapping to the adjacent finger.
- Volar dislocations are extremely rare and mostly managed by closed reduction but if unsuccessful then ORIF is required.
Collateral ligament rupture of MP joint
UCL is rare, RCL is more common, affects the ulnar 3 fingers, and presents with pain with passive flexion, tenderness on the radial aspect of the MCP joint, swelling, and ulnar deviation of the affected fingers.
Management: Immobilization at 30 degrees flexion for 3 weeks then re-assess if it is still unstable then buddy-tap it to the adjacent finger for another 2-3 weeks. If it is still not stable or painful then surgical repair is indicated.
Proximal interphalangeal joint dislocations
The most common site of ligamentous injury in the hand is the PIPJ.
The lateral collateral ligaments (proper / accessory) and volar plate prevent lateral deviation and hyperextension of the PIPJ respectively as shown in fig.15. The joint has to be disrupted in two planes for it to be dislocated.
Fig.15 box-shaped PIPJ formed of the collateral ligament and volar plate.19
Dorsal PIPJ Dislocation20
Usually due to hyperextension injuries with the ball hitting the tip of the finger causing longitudinal compression. The volar plate avulses distally in 80% of dorsal dislocations.
XR: The subluxation can be easily missed as the joint is reduced. The dorsal V sign is commonly seen indicating dorsal dislocation and malalignment of the dorsal articular surface which can be tested in flexion to test for the degree of malalignment and if it is unstable it won’t improve with the range of motion as shown in fig.16.
Fig. Dorsal v sign and unstable PIPJ on flexion due to volar plate avulsion fracture.
Classification of dorsal PIPJ dislocation (fig.16)
- Type I (hyperextension): 70-80 degrees hyperextension but there is still intact partial joint articulation.
- Type II (dorsal dislocation): complete dorsal displacement and vertical split of the collateral ligaments and there is no joint articulation.
- Type III (fracture-dislocation): the volar base of the middle phalanx is fractured and avulsed with the attached volar plate.
- Stable: Less than 40% of the volar articular surface of the middle phalanx is disrupted but the dorsal collateral ligament will be attached to the middle phalanx
- Unstable: more than 40% of the volar articular surface of the middle phalanx is disrupted and most of the collateral ligament and the volar plate will be attached to the fractured fragment. The reduction cannot be maintained.
Fig.16 Classification of dorsal PIPJ dislocation21
Treatment20,22
All types are treated non-operatively except unstable type III
- Type I: reduced and immobilized in a dorsal splint in 20-30 degrees flexion for a week.
- Type II: as type I but is immobilized for 2-3 weeks.
- Type III (stable): same as type I for 3 weeks and reduce the flexion by 10-15 degrees each week. Followed by exercises.
- Type III (unstable): for comminuted fractures, dynamic skeletal traction or hemihamate arthroplasty could be done. However, ORIF is better for large bony avulsed fracture fragment. If not possible then volar plate arthroplasty.
Lateral dislocations of PIPJ
Usually occurs when there is collateral ligament injury in addition to a tear in the volar plate. A complete collateral tear is considered if the joint deviates more than 20 degrees with a lateral stress test.
Management: Buddy taped and early range of motion is encouraged.
Surgical intervention is considered for subacute and chronic cases if the joint is unstable.19
Volar PIPJ dislocation13
These are rare (Fig.17).
- Volar dislocation: the base of the middle phalanx displaces volarly without rotation. The central slip is ruptured. Elson test is useful in identifying central slip injury by asking the patient to flex his PIP and DIP joints over the edge of the table and then asking him to extend the PIP joint against the resistance of the examiner. If there is a hyperextension or firm extension at the DIP joint this is indicative of central slip injury.
- Volar rotatory subluxation
is still attached to one collateral ligament leading to rotation.
Management:
- Closed reduction: By applying traction while MP and PIP joints are flexed. If adequate reduction is achieved and a stable joint post-reduction (clinically and radiologically), splint PIPj in extension for 4-6 weeks.
- Open reduction: If closed reduction unsuccessful.
Fig.17 volar dislocation PIPj
Distal interphalangeal joint and thumb interphalangeal joint
It has the same ligamentous anatomy in addition to the tendinous insertions of the extensors and flexors which provide more stability and decrease the risk of dislocations compared to the PIP joints. Dislocation is usually lateral or dorsal.
Management:
Non operative: dorsal splint for 2-3 weeks.
Operative: Failed closed reduction and presence of avulsion fracture of the FDP or FPL
Dorsal dislocation of thumb MP joint
Occur with hyperextension injuries due to rupture of the volar plate.
Management: Reduction and immobilization at 20 degrees MP flexion for two weeks then active mobilization for another 2 weeks within the dorsal blocking splint.