A boxer’s fracture is a common injury involving a break in the neck of the fifth metacarpal bone, the long bone connecting the little finger to the wrist. This injury typically occurs when a person strikes a hard object with a closed fist. While the fracture can cause significant pain and deformity, most cases heal successfully without the need for an operation. The decision between non-surgical and surgical treatment depends on the specific characteristics of the break.
Recognizing the Injury
The injury is usually caused by an axial load applied to a clenched fist, forcing the fifth metacarpal bone to bend until it fractures. This mechanism commonly results in an apex-dorsal angulation, where the bone fragments point toward the back of the hand. Symptoms include immediate, severe pain and tenderness focused on the little finger’s knuckle.
Swelling and bruising develop rapidly around the fracture site, and a noticeable change in the hand’s contour is common. The knuckle may appear sunken or flattened, and the little finger might look shortened or crooked. Diagnosis is confirmed using X-rays, which show the fracture’s location, displacement, and angulation of the bone fragments, guiding the treatment plan.
Non-Surgical Treatment Options
The majority of Boxer’s fractures are managed conservatively without an operation. For fractures with acceptable alignment, treatment begins with a short period of immobilization using an ulnar gutter splint or cast, which supports the injured finger and the one next to it.
The splint is often applied with the metacarpophalangeal (MCP) joint—the knuckle—flexed between 70 and 90 degrees. This specific position keeps the collateral ligaments from shortening, which helps prevent long-term joint stiffness. The period of immobilization is typically brief, lasting between one and four weeks, allowing for an earlier return to function.
If the initial X-ray shows excessive angulation, a procedure called closed reduction may be performed under local anesthesia to realign the bone fragments. After reduction, the hand is immobilized, and follow-up X-rays confirm stable alignment. Many fractures with angulation up to 70 degrees heal well with this conservative approach, offering functional outcomes comparable to surgical intervention.
When Operative Intervention is Necessary
Surgery is reserved for complex or unstable fractures where non-surgical methods cannot achieve or maintain proper alignment. The most common reason for operative intervention is excessive angulation. While the fifth metacarpal can tolerate significant angulation, up to 70 degrees, greater angles may lead to poor grip strength and functional impairment.
Rotational deformity, or malrotation, is considered a more serious indication for surgery than angulation. This occurs when the fractured finger overlaps or scissored over an adjacent finger during a fist. Unlike angulation, which the hand can often compensate for, rotational malalignment is poorly tolerated.
Other indications include open fractures, where the bone pierces the skin. Fractures that extend into the joint surface (intra-articular fractures), or those with significant shortening of the bone, typically exceeding five millimeters, also require surgery. Multiple metacarpal fractures or associated injuries, such as a dislocation at the wrist joint, increase the likelihood of surgery.
The Surgical Process and Post-Op Recovery
When an operation is necessary, the goal is to stabilize the bone fragments to promote healing. Two common techniques are used for internal fixation: percutaneous pinning and plate and screw fixation. Percutaneous pinning involves inserting small metal wires through the skin to hold the bone fragments together.
This method is less invasive, but the pins often remain exposed through the skin for several weeks, requiring careful pin site care to prevent infection. Open reduction and internal fixation (ORIF) involves making an incision to directly visualize and realign the fragments. The surgeon then uses small screws and a metal plate to stabilize the fracture.
Following surgery, the hand is immobilized in a splint or cast for several weeks. Once initial healing has progressed, the focus shifts to aggressive physical or occupational hand therapy. Rehabilitation involves exercises to restore the range of motion, strength, and flexibility lost during immobilization. Most individuals can expect a return to full activities between six and twelve weeks after the operation.