A Boxer’s fracture is a common injury involving a break in the neck of the fifth metacarpal bone, which connects the little finger to the wrist. This injury earned its name because it frequently results from punching a hard object with a closed fist, causing the bone to fracture and typically angulate towards the palm. Treatment depends on the fracture’s severity, particularly the degree of bone displacement and angulation. Most cases can be managed without surgery, but a detailed assessment is necessary to determine the best path to recovery.
Initial Assessment and Determining Treatment
A medical professional begins the process with a physical examination, checking for obvious deformity, swelling, and bruising, and assessing the hand for rotational malalignment. Rotational deformity is a significant finding where the little finger crosses over or under the ring finger when the patient attempts to make a fist, which can severely impact long-term hand function. X-rays are the definitive diagnostic tool used to confirm the fracture location and, more importantly, to measure the degree of angulation.
The angulation, or how much the bone is bent at the fracture site, is the primary factor dictating treatment. The fifth metacarpal has a remarkable capacity to heal and remodel, allowing for a higher degree of angulation than other hand bones. Angulation up to 70 degrees is sometimes considered acceptable for non-operative management, though many surgeons prefer to intervene if the angulation exceeds 30 degrees. If the fracture is stable and the angulation is within an acceptable limit, the treatment will involve simple immobilization.
Immobilization and Closed Reduction
For fractures that are minimally displaced or within the acceptable angulation range, non-surgical treatment is the standard approach. This management focuses on immobilization to allow the body’s natural healing process to solidify the bone segments. For fractures that exceed the acceptable angulation threshold or show rotational issues, a procedure called closed reduction is performed.
Closed reduction involves manually manipulating the fractured bone fragments back into a satisfactory alignment without making a surgical incision. This is often performed under local anesthesia, such as a hematoma block, to numb the area and minimize patient discomfort. A common reduction technique is the 90-90 method, where the metacarpophalangeal (MCP) joint is flexed to 90 degrees, and a dorsally directed force is applied to the finger to push the bone head back into position.
Following the reduction, the hand is immediately immobilized using a cast or splint, such as an ulnar gutter splint, which supports the ring and little fingers. The splint is specifically positioned to keep the MCP joints flexed at 70 to 90 degrees and the interphalangeal joints extended, a position that helps maintain the reduction and prevents joint stiffness. Immobilization typically lasts for three to four weeks, during which follow-up X-rays are taken to confirm the fracture remains stable and in good alignment. In some highly stable, non-displaced fractures, a less restrictive approach like buddy taping the little finger to the ring finger may be used.
When Surgery is Necessary
Surgery is reserved for specific conditions where non-operative treatment is unlikely to result in a functional hand or has failed to maintain the bone alignment. Indications for surgical intervention include an open fracture where the bone has broken through the skin, the involvement of multiple metacarpals, or a failure to achieve or maintain reduction. Surgery is also usually performed if the fracture causes a severe rotational deformity, which can lead to the finger overlapping its neighbor when making a fist, significantly impairing grip.
Two primary surgical techniques are employed to stabilize the fracture. Closed Reduction and Percutaneous Pinning (CRPP) involves realigning the fracture manually, and thin metal wires, known as K-wires, are inserted through the skin to hold the bone fragments in place. Open Reduction and Internal Fixation (ORIF) requires an incision to directly visualize the fracture, realign the fragments, and secure them with small plates and screws. While surgery ensures better anatomical alignment, it carries risks such as infection, hardware irritation, and a longer overall recovery period compared to non-operative management.
Recovery and Regaining Hand Function
After the period of immobilization, whether by splint or post-surgery, the focus shifts to rehabilitation to restore full hand function. The hand often experiences stiffness, swelling, and weakness immediately after the cast or splint is removed due to being held in a static position for several weeks. Patients will often be referred to a hand therapist to begin a regimen of exercises.
Hand therapy focuses on regaining a full range of motion, starting with gentle active exercises for the joints. As the bone solidifies, exercises to improve grip strength and dexterity are introduced, often involving squeezing soft putty or using resistance bands. A general timeline for returning to light daily activities is typically a few weeks after immobilization ends, but avoiding heavy lifting and contact sports is usually recommended until the bone is solidly healed, which can take eight to twelve weeks from the initial injury.