Courtesy: Prof Nabil Ebraheim, University of Toledo, Ohio, USA

Seymour Fracture

Definition

• Open physeal fracture of the distal phalanx.
• Usually a Salter Harris Type I or II injury.
• Associated with a nail bed injury.
• Frequently mistaken for a mallet finger.

Mechanism of Injury

• Crush injury to the fingertip.
• Finger caught in a closing door.
• Flexion force applied to the distal phalanx.

Pathoanatomy

• Fracture through the distal physis.
• Extensor tendon disruption.
• Flexor digitorum profundus remains intact, producing a flexion deformity.
• Nail plate becomes interposed within the fracture site.

Clinical Features

• Flexion deformity of the fingertip resembling a mallet finger.
• Displaced or superficially positioned nail plate.
• Bleeding at the nail fold.
• Swelling and pain.

Diagnostic Clues

• Bleeding around the nail fold should be considered evidence of an open fracture until proven otherwise.
• Maintain a high index of suspicion even when deformity appears minimal.

Imaging

• Anteroposterior and lateral radiographs of the finger.
• Physeal fracture of the distal phalanx.
• Fracture displacement may be subtle.

Seymour Fracture versus Mallet Finger

Seymour fracture

• Open physeal fracture.
• Nail bed injury is present.
• High risk of infection.
• Requires surgical treatment.

Mallet finger

• Extensor tendon avulsion with or without a small bony fragment.
• Nail bed is intact.
• Low risk of infection.
• Usually treated conservatively.

Complications

• Infection.
• Nail deformity.
• Growth disturbance.
• Malunion.

Treatment

• Treat as an open fracture.
• Administer antibiotics.
• Provide tetanus prophylaxis when indicated.
• Remove the nail plate.
• Perform irrigation and debridement.
• Achieve anatomical fracture reduction.
• Stabilize with K wire fixation if required.
• Repair the nail bed.

Immobilization

• Protect the finger with a splint or cast following fixation.

Exam Pearls

• Seymour fracture should always be considered an open fracture until proven otherwise.
• Bleeding at the nail fold is an important diagnostic clue.
• Commonly misdiagnosed as a mallet finger.
• Nail plate interposition is a characteristic finding.
• Prompt surgical management is essential to prevent infection and growth disturbance.