Makindo Medical Notes

Introduction

A Boxer’s fracture refers to a fracture of the neck of the 5th metacarpal, typically resulting from a direct blow to the distal-dorsal aspect of a closed fist. It is one of the most common fractures of the hand, often occurring when an individual punches a hard object, such as a wall or another person. Though commonly associated with fighting, these fractures can occur in any situation involving blunt trauma to the hand.

Mechanism of Injury

Boxer’s fractures usually occur when a clenched fist strikes a hard surface. The force of the impact drives the distal 5th metacarpal head into the palm, resulting in a volar angulation of the metacarpal neck. This angulation, particularly at the neck of the 5th metacarpal, leads to the typical deformity seen in this type of fracture.

Clinical Presentation

• Pain and swelling over the dorsal aspect of the hand, particularly at the base of the little finger.
• Loss of knuckle prominence, with flattening of the knuckle, when making a fist (due to displacement of the metacarpal head).
• Pain and limited movement when trying to form a fist.
• Occasional rotation of the 5th finger, which can be noted when the patient tries to flex their fingers.
• Bruising over the dorsal aspect of the hand.

Diagnosis

• Physical Examination: Tenderness over the 5th metacarpal with possible deformity and loss of knuckle prominence.
• Imaging:
  • AP, lateral, and oblique X-rays of the hand are the imaging modality of choice. These will demonstrate the fracture, degree of angulation, and any associated injuries.
  • Check for rotational deformities by asking the patient to make a fist—misalignment of the fingers suggests rotation of the fractured bone.

Management

Management of a Boxer’s fracture depends on the degree of angulation and the presence of any rotational deformities.

• Closed Reduction: Indicated if volar angulation exceeds 40 degrees. The goal is to realign the metacarpal to prevent long-term functional and cosmetic issues.
• Immobilization: If the fracture is stable (after reduction or if angulation is within acceptable limits), the patient is placed in an ulnar gutter splint for 4-6 weeks to allow proper healing.
  • Ulnar gutter splint should be applied with the hand in a position of function (wrist slightly extended, MCP joints flexed at 70-90 degrees, and IP joints in extension).
• Indications for Surgery:
  • Significant rotational deformity that cannot be corrected through closed reduction.
  • Fractures that remain unstable after reduction.
  • Open fractures or those with significant soft tissue injury.

Follow-up and Prognosis

Regular follow-up appointments are essential to monitor healing and ensure that the fracture is properly aligned. Repeat X-rays may be taken after one week to confirm stability.

• Most Boxer’s fractures heal well with conservative management and do not lead to significant long-term complications.
• In cases of delayed treatment or inadequate reduction, patients may experience malunion, leading to cosmetic deformities or reduced grip strength.
• Post-reduction exercises to restore range of motion and strength should be initiated once the splint is removed.

Complications

• Malunion, resulting in a permanent deformity of the hand.
• Loss of grip strength or reduced range of motion.
• Persistent pain or stiffness.
• Non-union or delayed healing in severe cases.