A Boxer’s fracture is a frequently encountered hand injury resulting from a sudden, forceful impact to a closed fist. This injury is one of the most common breaks seen in the bones of the hand. This article explores the specific anatomy involved, how the injury is identified, and the expected path toward recovery.
Defining the Injury
A Boxer’s fracture is a break near the end of one of the metacarpal bones in the hand, specifically involving the neck of the bone just beneath the knuckle. The injury most commonly affects the fifth metacarpal (little finger), though the fourth metacarpal (ring finger) is also sometimes involved. The name derives from the mechanism of injury, which is typically an axial load applied when a clenched fist strikes a solid object.
The force from the impact travels through the length of the bone, causing a fracture at the weakest point, the metacarpal neck. This break nearly always results in the fractured bone segment bending toward the palm, a displacement known as apex dorsal or volar angulation. The natural pull of the small muscles in the hand contributes to this specific angle of the fracture.
Recognizing the Signs
The injury presents with immediate and acute pain centered at the site of the break, accompanied by rapid swelling and bruising on the back of the hand. A noticeable symptom is the loss or depression of the knuckle, as the head of the metacarpal bone shifts downward toward the palm. The hand may also display a rotational deformity, where the injured finger appears to cross over or under the adjacent finger when attempting to make a fist.
Diagnosis begins with a thorough physical examination to check for tenderness, swelling, and evidence of rotational misalignment. A neurovascular assessment is performed to ensure the nerves and blood vessels to the finger are intact. X-rays are taken to confirm the diagnosis, determine the severity, and precisely measure the degree of angulation and rotational malalignment of the bone fragments.
Treatment Options
The approach to treatment is dictated by the severity of the fracture, primarily the degree of angulation and the presence of any rotational deformity. Fractures with minimal angulation and no rotation are managed non-surgically with immobilization in a splint or cast. This conservative treatment involves a short arm splint, such as an ulnar gutter splint, to hold the hand in a position that promotes healing.
If the angulation is beyond an acceptable limit—often considered more than 30 to 40 degrees for the fifth metacarpal—or if rotational deformity exists, a closed reduction procedure is performed. This involves manually manipulating the hand to push the bone fragments back into proper alignment while the patient is under local anesthesia. After successful reduction, the hand is immobilized in a cast or splint.
For severely displaced, unstable, or complex fractures, surgical intervention may be required. Surgical techniques include Closed Reduction and Percutaneous Pinning, where small wires or pins are inserted through the skin to stabilize the bone fragments. Alternatively, Open Reduction and Internal Fixation (ORIF) may be necessary, involving an incision to directly realign the bone, which is then secured with small plates or screws.
Recovery and Return to Activity
Following initial treatment, the hand is typically immobilized in a cast or splint for four to six weeks to allow for bone consolidation. Early mobilization is encouraged for less severe fractures, sometimes beginning after just one week of splinting. Once the cast is removed, the hand often exhibits stiffness, reduced range of motion, and decreased grip strength.
Physical therapy is necessary to restore full function, focusing on gentle range-of-motion exercises and tendon gliding activities to prevent stiffness. This rehabilitation phase gradually transitions into strengthening exercises for the hand and forearm muscles. A full recovery and return to regular activities, including non-contact sports, generally occurs between six and eight weeks, though contact sports may require up to twelve weeks.