Fracture, Distal Phalanx

By admin On Dec 3, 2023

Ovid: 5-Minute Sports Medicine Consult, The

Thomas L. Pommering

Basics

Fractures of the distal tip (Tuft fracture):
- Open
- Closed
Fractures of the shaft:
- Longitudinal
- Transverse
Fractures of the base:
- Mallet fracture
- Reverse mallet fracture (jersey finger)
- Pediatric epiphyseal fractures:
  - Salter-Harris type I or type II
  - Seymour fracture (pediatric jersey finger)

Description

Mallet finger: A pure tendon injury where there is disruption of the extensor tendon caused by forced flexion of the fingertip while the distal interphalangeal (DIP) joint is in extension; the result is that the active extension of the DIP joint is lost, leaving the fingertip in slight flexion
Mallet fracture: A disruption of the terminal extensor tendon from its insertion onto the proximal aspect of the distal phalanx dorsally with a bony avulsion
Jersey finger: Flexor digitorum profundus (FDP) rupture from its insertion onto the palmar distal phalanx; can be a pure tendinous injury or include a bony avulsion
Swan-neck deformity: Reverse boutonniere deformity; hyperextension of the proximal interphalangeal (PIP) joint caused by disruption of the volar plate attachment to the middle phalanx causing relaxation of the extensor mechanism and allowing the unopposed flexor digitorum to draw the distal phalanx into flexion; often the result of an undiagnosed or untreated mallet finger or mallet fracture
Seymour fracture: Extraarticular transverse fracture of the base of the distal phalanx usually involving the distal physis (SH I or II) or 1–2 mm distal to the physis; this fracture mimics mallet finger deformities but does not involve the articular surface. The FDP tends to pull the distal metaphyseal fragment volarly, whereas the extensor tendon insertion onto the proximal aspect of the distal phalanx pulls the epiphysis dorsally, in the opposing direction.
Tuft fracture: A fracture of the distal tip of the distal phalanx; usually from a crush injury and associated with a subungual hematoma and/or a nail bed injury; can be an open or closed injury.

Epidemiology

Incidence

Most common peak incidence is during early teenage years, followed by a second peak during toddler years (crush injury in doors)
In the pediatric population, physeal fractures of the phalanges account for 37% of all physeal fractures, with the small finger being affected most often (30%), followed by the thumb (20%).
Hand injuries, in general, account for 9% of all sports injuries.
Seen more often with contact sports, where direct trauma is more likely (eg, football), or with sports where the hand is exposed to projectiles (eg, baseball)

Risk Factors

Crush injury to tip of finger (eg, getting stepped on by opponent's spiked shoes) results in comminuted fracture or tuft injury.
Acute flexion of an extended DIP joint (eg, catching a ball on the tip of the finger or striking an object with the finger extended) results in mallet finger.
Forced extension while actively flexing the DIP joint (eg, grabbing a jersey of a ball carrier in football or catching the rim while dunking a basketball) results in jersey finger.

General Prevention

Seen more often with contact sports where direct trauma is more likely (eg, football) or with sports where the hand is exposed to projectiles (eg, baseball)
Buddy taping to the adjacent digit or interphalangeal joint taping for high-risk athletes

Etiology

The tip of the distal phalanx ends with broad, spadelike ungual tuberosity that provides a stable and protective base for the distal digital pulp.
On the palmar surface, the FDP inserts onto the midportion of the distal phalanx.
On the dorsal side, the terminal extensor tendon attaches to the proximal aspect of the distal phalanx (or the epiphyseal plate in children), blending with the joint capsule and periosteum.
Collateral ligaments span the DIP joint (or the epiphyseal plate in children) and insert onto the metaphysis of the distal phalanx.
Lateral interosseous ligaments originate on and span the distance of the distal phalanx, protecting the neurovascular bundle as they pass dorsally from the pulp to the nail bed.

Diagnosis

History

Crush, torsional, or hyperflexion/hyperextension mechanism (“jammed finger”)
Blunt trauma or projectile force against the fingertip resulting in forced flexion: Mallet finger/fracture
Forced extension on a flexed distal phalanx (eg, grabbing a jersey during a tackle): Jersey finger

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Physical Exam

Signs and symptoms include:
- Pain, swelling, and ecchymosis
- Loss of range of motion (ROM), malalignment or angular deformities noted with flexion
- Obvious deformity, especially if associated with dislocation
- Subungual hematomas
- Traumatic swelling and tenderness over the volar aspect of the distal phalanx with additional palmar pain is a rupture of the FDP until proven otherwise.
Physical examination should include the following:
- Sites of tenderness, loss of active ROM, evidence of instability, and neurovascular examination
- Radiographs should be obtained before any manipulative examination.
- Mallet finger: 40–45-degree loss of extension at the DIP joint with inability to extend the distal phalanx; there also is pain and swelling over the dorsal aspect of the joint.
- Jersey finger: Inability to flex the distal phalanx, with tenderness over the volar aspect of the joint and in the palm secondary to retraction of the tendon after rupture

Diagnostic Tests & Interpretation

Imaging

Imaging should be obtained before any manual reduction attempts.
Three views of the affected digit: Anteroposterior (AP), lateral, and oblique views
Consider comparison views of the unaffected side when skeletal immaturity is involved.
Rarely do MRI, CT scan, or US add useful diagnostic information for distal phalangeal injuries.
- MRI is occasionally useful to delineate soft tissue ligamentous or tendon injury.
- CT scan is occasionally useful to delineate osseous injury for preoperative planning.

Differential Diagnosis

Fracture
Sprain
Tendon rupture or avulsion
Interphalangeal dislocations

Treatment

Distal phalanx or tuft fractures:
- Closed with minimal to no displacement:
  - Inherently stable
  - Often have an associated subungual hematoma that may need evacuated (see “Other Procedures”) for pain control
  - Ice for swelling and pain control
  - Simple moldable aluminum splint covering the tip of the finger for support and protection; usually not needed for more than 3 wks
  - Union by 6–8 wks
- Open:
  - Inherently unstable because of disruption of the supporting pulp and nail bed
  - Require careful débridment, irrigation, and soft tissue repair often with loop magnification
  - Oral antibiotics and tetanus prophylaxis
  - Consider surgical consultation.
Shaft fractures:
- Closed longitudinal or transverse shaft:
  - Usually inherently stable
  - Longitudinal fractures: Heal within 3–4 wks; splint for protection
  - Transverse fractures: Take longer, requiring slightly longer support until clinical discomfort abates or radiographic union is evident
- Open shaft fractures:
  - Unstable; also often associated with underlying nail bed injury
  - Proper alignment is necessary.
  - Surgical consultation is recommended.
Base-of-phalanx fractures:
- Tend to be unstable regardless of the overlying soft tissue involvement owing to the deforming traction of the extensor or flexor tendons
- Lack the intrinsic support of the overlying nail and nail plate
- Tend to angulate with the apex pointing dorsally
- If >1/3 to 1/2 of the articular surface is involved or if displaced, consider surgical consultation.
Closed nondisplaced fracture of the dorsal surface in adults (mallet fracture):
- Continuous 24 hr/day splinting with the DIP joint in extension using a molded volar aluminum splint or properly fitted polythene (Stack) splint for 6–8 wks; night splinting is recommended for an additional 2–6 wks.
- Hyperextension of the DIP joint should be avoided.
- PIP joint is always left free.
- Any momentary loss of extension (eg, during changing or removal of splint for hygiene) mandates restarting back at day 1 of immobilization.
- Some extension lag after treatment is expected.
- The goal is to prevent a hyperextension PIP joint deformity (swan-neck deformity).
- Because the surgery often is deceptively difficult to perform and is associated with several complications, operative management is reserved for injuries with volar subluxation of the distal phalanx or if displaced and involving >50% of the joint surface.
- Discussion with your surgical consultant is advised.

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Mallet finger:
- Pure tendon injury with normal radiographs
- Treated similarly to mallet fracture with 6–8 wks of continuous 24 hr/day DIP joint splinting followed by night splinting
- Failed or interrupted treatment can be restarted because extended splinting time will not alter clinical outcomes and may even yield good results.
- Conservative treatment is preferred owing to the complication risks of surgical treatment.
Closed nondisplaced fracture of the volar surface in adults (jersey finger):
- Essentially opposite of mallet finger
- Ring finger involved 75% of the time
- Avulsed fragment from the volar surface is attached to the FDP, which tends to promote displacement.
- Prompt surgical referral (within 7–10 days) should be the rule to optimize full functional outcome and avoid late complications.
- Rare injury in children (see below); when present, usually occurs in adolescents near skeletal maturity
Pediatric considerations:
- Children <5 yrs of age often have a SH I or II fracture (Seymour fracture).
- The FDP tendon is attached to the distal shaft, pulling it in the volar direction, whereas the epiphysis remains extended owing to the traction of the extensor tendon.
- Extraarticular fracture of the base of the distal phalanx before closure of the epiphysis
- Clinically, mimics mallet fracture or DIP joint dislocation (although is not an intraarticular injury)
- Splint application for up to 6 wks in slight hyperextension
- Close follow-up with weekly lateral radiographs for the 1st 2 wks to confirm alignment and stability to prevent permanent deformity
- Surgical referral for open fractures, those not amenable to closed reduction, or if unfamiliar with treatment of this injury in children
Reduction techniques:
- Transverse or comminuted distal phalanx fractures: No reduction usually is required, only protective splinting for 3–4 wks, elevation, and analgesics. Treat associated subungual hematomas.
- Displaced distal phalanx fractures with AP displacement: Apply traction to the distal aspect, and mold the fragments by squeezing the end of the finger between your thumb and index finger. Lateral displacement is corrected by compressing the lateral borders of the terminal phalanx with your thumb and index finger. Be aware that these can be difficult to reduce when soft tissues become interposed between fragments. If uncorrected, this may lead to nonunion.
Postreduction evaluation:
- Repeat radiographs
- Neurovascular examination

Pre-Hospital

Protect and splint

Medication

If reduction is needed or repair of associated soft tissue injuries (eg, nail bed laceration), a hematoma block, digital block, or wrist block can be used.
Conscious sedation or reduction under general anesthesia may be needed.

Second Line

Chronic pain control usually can be achieved with nonnarcotic analgesics or mild narcotic pain medication.

Additional Treatment

Hematoma evacuation from the nail bed when >30–50% of the nail is involved or there is a need for pain control
Usually accomplished using either a heated paper clip or electric cautery device

Referral

Displaced fractures not responsive to manual reduction
Anytime there is suspected flexor tendon involvement
Open fracture of the shaft or intraarticular fracture
Open tuft fractures are often unstable and involve complex injuries to the nail bed requiring skilled repair under loop magnification.
Suspected neurovascular injury or secondary infection

Additional Therapies

With fractures associated with subungual hematomas involving >30–50% of the nail, concomitant nail bed lacerations should be suspected and repaired if present. This is usually done using 5–0 or 6–0 dissolvable sutures and replacing the nail plate if possible. This is treated as an open fracture in the sense that it should be done under sterile conditions followed by antibiotic coverage for 7–10 days.
Physical therapy with a qualified hand therapist is recommended in postoperative cases, after prolonged immobilization, and after splinting mallet finger if return to full ROM is not progressing.
With mallet finger, patients should be warned against strong passive ROM in an attempt to hasten flexion owing to the risk of additional damage to the extensor insertion. Gradual progression is usually the rule.

Surgery/Other Procedures

FDP tears or jersey finger
Mallet finger with volar subluxation of the distal phalanx
Comminuted distal phalanx fracture with significant displacement (Tuft fracture)
Any distal phalanx fracture with malalignment that is not reducible by closed methods

In-Patient Considerations

Generally reserved for severe, infected, or complicated injuries requiring surgical intervention

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Ongoing Care

Follow-Up Recommendations

Repeat radiographs:

Mallet fractures: Consider at 1–2 wks to document stability (x-ray in splint) and possibly at 4–6 wks if there is any evidence of extension lag
Pediatric epiphyseal fractures (including Seymour fracture): At 1–2 wks to document stability; optional at 4 wks as the clinical picture dictates
Longitudinal and transverse shaft fractures: At 2 wks

Prognosis

In general, distal phalanx fractures are usually stable and heal with an uneventful course.

Complications

Nonunion or malunion
Infection for open fractures
Joint stiffness or arthrofibrosis
Permanent loss of flexor tendon function or dysfunction with undiagnosed or delayed treatment for flexor tendon avulsions or disruptions
Physeal arrest in children
Avascular necrosis with displaced unicondylar fractures, especially in children
Swan neck deformity
Neurovascular injury
Skin necrosis from splints applied too tightly
Skin hypersensitivity with distal injuries
Osteoarthritis for late, undiagnosed, or inadequately healed intraarticular fractures

Additional Reading

Flynn JM, Nagda S. Upper extremity injuries. In: Dormans JP, ed. Pediatric orthopaedics and sports medicine. 1st ed. St. Louis: Mosby, 2004:21–25.

Heaps RJ, Levin LS. In: Garrett WE, Speer KP, Kirkendall DT, eds. Principles and practice of orthopaedic sports medicine. 1st ed. Philadelphia: Lippincott Williams & Wilkins, 2000:235–236.

Jobe MT, Calandruccio JH. Fractures, dislocations and ligamentous injuries. In: Canale ST, ed. Campbell's operative orthopedics. 10th ed. Philadelphia: Mosby, 2003:3515–3516.

Jupiter JB, Axelrod TS, Belsky MR. Fractures and dislocations of the hand. In: Browner BD, Jupiter JB, Levine AM, et al. eds. Skeletal trauma: basic science, management, and reconstruction. 4th ed. Philadelphia: W.B. Saunders, 2008:121–141. (accessed on line www.mdconsult.com, 8/25/09).

Leggit JC, Meko CJ. Acute finger injuries: part II. Fractures, dislocations, and thumb injuries. Am Fam Physician. 2006;73:827–834, 839.

Lindley SG, Rulewicz. Hand fractures and dislocations in the developing skeleton. Hand Clin 2006;22:253–268.

Papadonikolakis A, Zhongyu L, Smith BP et al. Fractures of the phalanges and interphalangeal joints in children. Hand Clin. 2006;22:11–18.

Peterson JJ, Bancroft LW. Injuries of the fingers and thumb in the athlete. Clin Sports Med. 2006;25:527–542.

Shepler T. The pediatric hand. In: DeLee JC, Drez D, Miller MD, eds. DeLee and Drez's orthopaedic sports medicine. 3rd ed. Philadelphia: Saunders, 2009:1–43 (accessed on line www.mdconsult.com, 8/25/09).

Waters PM. The upper limb. In: Morrissy RT, Weinstein SL, eds. Lovell and Winter's pediatric orthopaedics. 5th ed. Philadelphia: Lippincott Williams & Wilkins, 2001:886–887.

Codes

ICD9

736.1 Mallet finger
816.02 Closed fracture of distal phalanx or phalanges of hand
816.12 Open fracture of distal phalanx or phalanges of hand

Clinical Pearls

Patients who remove a stack splint even for a moment (eg, during the treatment of mallet finger) must start treatment over at day 1.
- Proper healing depends on continuous splinting of the DIP joint for 6–10 wks. To ensure this, patients are shown how to change their splints while keeping the DIP joint extended against a hard surface before splint application. Patients are seen again after 1–2 wks to be sure that they have complied or can comply with the strict protocol.
Late, untreated mallet fingers with no functional problems need not be treated.
With mallet finger, some experts recommend a second course (8 wks) of full-time splinting in the event of significant extensor lag after initial splinting.
Return to play with uncomplicated distal phalanx fracture depends on several factors:
- Athlete's (and parent's, if a minor) wishes and expectations. They need to be involved in the decision and understand the risks and benefits.
- Rules governing the athlete's sport and whether an effective splint that meets the safe play criteria be fabricated.
- Athlete's sport and/or position: Will splint protect the DIP joint and allow the athlete to play at a competitive level?
- Depending on the athlete and his or her age and maturity, many times he or she can return to play in a protective splint once the initial swelling and pain have subsided.