A Boxer’s fracture, a common injury often sustained from striking a hard object with a closed fist, is a break in the neck of the fifth metacarpal bone, the long bone connecting the wrist to the pinky finger. The good news is that most of these fractures can be treated successfully without surgery, but the decision is always based on the specific characteristics of the break. Treatment for this fracture is highly individualized, depending on the severity of the bone displacement and alignment.
Defining the Injury
This injury involves the metacarpal supporting the little finger, making it the most frequent type of hand fracture seen in emergency departments. The mechanism of injury is typically axial loading, where a force is driven straight down the length of the bone. Patients usually experience immediate pain, significant swelling, and bruising on the outer side of the hand, near the knuckle. A visible deformity, where the knuckle appears sunken or the finger looks bent, can also be present. The most important characteristic determining treatment is the degree of “angulation,” which refers to how much the broken bone fragments have bent away from their normal straight alignment. This angulation is typically measured from X-rays and is a key factor in deciding whether the fracture is stable enough for non-surgical care.
Standard Non-Surgical Management
Treatment often begins with a procedure called closed reduction, where a clinician manually manipulates the hand to realign the broken bone fragments without making an incision. This is usually performed after the area is numbed with a local anesthetic. Following a successful reduction, the hand is immobilized using a cast or specialized splint, such as an ulnar gutter splint. The splint keeps the wrist and the fourth and fifth fingers protected, often molded to hold the metacarpophalangeal (MCP) joints in a flexed position to maintain alignment. Immobilization typically lasts for approximately three to six weeks, allowing the bone a chance to heal, with repeat X-rays taken during the first week to ensure the reduction has held and the fragments have not shifted.
When Surgery Becomes Necessary
The most common indication for surgical intervention is excessive angulation, generally considered to be greater than 30 to 40 degrees for the fifth metacarpal, though some literature suggests angulations up to 70 degrees may be acceptable. Surgeons use these thresholds as guidelines because the hand can tolerate a greater degree of angulation in the mobile fifth metacarpal compared to the other fingers. A more significant concern than angulation is the presence of rotational deformity, where the finger twists along its long axis. Even a small amount of rotation is poorly tolerated because it causes the little finger to cross over the adjacent ring finger when making a fist, severely affecting grip function. Other indications for surgery include open fractures (where the skin is broken by the bone fragments) or severely comminuted fractures (involving multiple bone pieces), with the operation performed to restore proper anatomical alignment and stability beyond what can be achieved through non-surgical methods.
Healing and Return to Function
Regardless of whether the fracture is treated with or without surgery, the initial period of immobilization is typically four to six weeks for the bone to achieve a stable union. Once the cast or splint is removed, patients often notice stiffness in the finger joints, which is a common consequence of prolonged immobilization. At this stage, physical therapy becomes a highly important part of the recovery process, focusing on restoring the full range of motion in the finger and hand and rebuilding grip strength. While a small bump or a slightly less prominent knuckle may remain at the fracture site, this generally does not affect the long-term function of the hand. Most patients can expect a good recovery and an eventual return to sports and other activities, often within two to three months following the injury, provided they adhere to their rehabilitation program.