Boxer’s Fracture - Causes, Symptoms, Diagnosis, and Treatment

Introduction

The hand comprises many parts, like bones, tendons, ligaments, and muscles. The hand utilizes these components collectively to perform various tasks. The metacarpals are the long bones in the palm that connect the wrist bones to the fingers. They are labeled as one, two, three, four, and five, beginning from the side where the thumb is. Fractures in the metacarpal bones make up 40% of all hand fractures.

What Is a Boxer’s Fracture?

A boxer's fracture happens when the neck of the fifth metacarpal bone is broken. This usually happens when the hand is hit directly while it is tightly closed in a fist.. Boxer's fractures make up 10 % of all hand fractures. This fracture is significantly more frequent in males, with males between the ages of 10 and 19 having the highest incidence, followed by males aged 20 to 29.

What Causes a Boxer’s Fracture?

The mechanism of injury primarily involves direct trauma to a clenched fist. Boxer's fractures can be due to various factors like:

• A primary cause of a boxer's fracture is the forceful impact of a clenched fist against a solid surface, often seen in scenarios such as sports-related activities, altercations, or accidents where the hand forcefully contacts a rigid object.

• Athletes, particularly those engaged in combat sports like boxing and martial arts, face an elevated risk of boxer fractures due to the repetitive high-impact stress on their hands.

• Falling onto an outstretched hand or striking the hand against the ground can result in a boxer's fracture, especially when the hand is clenched during the fall.

• Individuals employed in manual labor or operating heavy machinery are susceptible to boxer's fractures as accidents in the workplace may lead to this condition.

What Are the Symptoms of a Boxer’s Fracture?

Common symptoms include:

• The most prominent symptom of a boxer's fracture is localized pain in the hand at the site of the fracture.

• The injured area may become swollen, which is the body's natural response to injury.

• In some cases, a visible deformity, such as an angulated or crooked finger, may be present.

• Limited ability to move the finger and trouble with moving it are common signs of a boxer's fracture.

• Bruising around the injured area is a typical symptom, as damaged blood vessels can leak blood into the surrounding tissues.

• Numbness or tingling in the affected finger may occur due to nerve compression or damage.

How Is a Boxer’s Finger Diagnosed?

Boxer’s finger is diagnosed by a complete physical examination along with different imaging tests.

Physical Examination.

• The skin is closely examined for any breaks or injuries, particularly near the metacarpal head, which is the point of impact in most cases.

• In cases where a blow to the face causes the fracture, it is important to look for lacerations or abrasions known as "fight bites." These may require surgical irrigation and debridement.

• A neurovascular exam checks how well the body part beyond the injury can feel, move, and get enough blood. This helps ensure there is no damage to nerves or blood vessels.

• Boxer's fractures are often associated with apex dorsal angulation, resulting in depression of the metacarpophalangeal (MCP) joint and a loss of the normal knuckle contour.

• Severe angulation can lead to pseudo-clawing, characterized by hyperextension of the MCP joint and flexion at the proximal interphalangeal (PIP) joint.

• Rotational alignment is assessed by examining the hand with the MCP and PIP joints in flexion and the extended distal interphalangeal (DIP) joints.

• Comparing the injured hand to the uninjured one is also important in diagnosing the condition.

Imaging Tests

• Plain radiographs, including anteroposterior, lateral, and oblique views, diagnose a boxer’s fracture. The lateral view is crucial for measuring the degree of angulation in the metacarpal shaft compared to the fracture fragment's midpoint.

• While CT scans are not routinely used for diagnosing metacarpal fractures, they may be necessary to detect occult fractures in cases with high clinical suspicion for fracture, and plain radiographs appear negative.

How Are Boxer’s Fractures Managed?

The appropriate treatment for a Boxer's fracture depends on factors like whether it is an open or closed fracture, the degree of angulation or rotation, and any associated injuries.

Immobilization:

• If the Boxer's fracture is closed (no break in the skin), not angulated (not bent too much), and not rotated or displaced, it can be initially treated with immobilization.

• Ulnar Gutter Splint - An initial approach is immobilizing the fractured hand using an ulnar gutter splint. This splint provides support and protection for the injured area.

• Buddy Taping - Alternatively, a simpler method known as buddy taping can be used in uncomplicated cases. This involves tapping the little and ring fingers together. Buddy taping is effective in reducing the risk of rotational deformity.

• The hand is positioned specifically during splinting to prevent loss of motion and functional problems.

Closed Reduction:

• If the Boxer's fracture has significant angulation (bent too much, over 30 degrees), it may require a closed reduction.

• For pain control during this procedure, the doctor might use local anesthesia. Young children or very anxious patients may need sedation, but most people can tolerate this procedure without it.

• The doctor will use the 90-90 method, where they flex the knuckle and finger joints to 90 degrees. Pressure is applied to the top part of the fracture while pushing down on the bent finger joint. This helps align the fractured bone.

• The hand is then put in an ulnar gutter splint, and follow-up X-rays are taken to ensure the bone is aligned correctly.

Surgical Treatment:

• Surgical options include open reduction internal fixation (ORIF) or closed reduction with percutaneous pinning, where pins are inserted through the skin to hold the bone in place.

• Kirschner wires are often used for stable fractures when conservative methods are insufficient. They are minimally invasive and easy for percutaneous and open fracture stabilization.

• Intramedullary fixation involves placing implants like nails or headless screws within the bone's medullary canal.

• Plate and screw fixation is preferred when dealing with significant comminution (bone breaking into several pieces) or multiple metacarpal neck fractures.

• Surgical treatment is required in the following cases:

  • Open fracture.

  • Complex or multiple fractures.

  • Fracture extends into the head of the metacarpal.

  • Malunion and non-union.

  • Fracture extends into the joint.

  • Shortening of the metacarpal bone by more than 5 mm.

  • Volar angulation, where the fracture fragment bends toward the palm.

  • Rotational deformity, where the finger is twisted.

  • Failure to achieve proper realignment and reduction.

Follow-Up:

• Patients with Boxer's fractures should be closely monitored with regular follow-up visits.

• X-rays are typically taken within a week and continued every two weeks until clinical and radiographic healing is confirmed (usually in four to six weeks).

• Follow-up care may involve hand exercises to prevent stiffness and improve range of motion.

Conclusion

Complications of boxer’s fracture are rare, and the commonly occurring ones include malunion, loss of the esthetic appearance of the finger, and digital malrotation. Most boxer's fractures heal well when managed appropriately, and patients can regain full hand function. Many patients can expect a return to their regular activities and work within a reasonable time frame.