The clenched fist injury classically occurs when the metacarpophalangeal (MCP) joint contacts human teeth, resulting in a laceration. Many patients will not divulge the true circumstances surrounding the injury; all wounds at the MCP joint, especially of the dominant hand, must be considered a fight bite until proven otherwise. Serious complications can result, including infection, loss of function, and amputation. Most wounds are polymicrobial. Patients who present early may have little evidence of intra-articular injury on examination, whereas those who present more than 18 hours after injury are more likely to have evidence of infection, including pain, swelling, erythema, and purulent drainage.
Management and Disposition
All wounds should be irrigated, debrided, explored, and immobilized. Patients should receive antibiotics directed at both oral and skin flora. Augmentin is the treatment of choice unless a patient has a penicillin allergy. Tetanus prophylaxis is given if needed. Radiographs should be obtained to evaluate for fractures and foreign bodies. These wounds should never be closed and should be allowed to heal by secondary intention. Reliable patients who present early, without evidence of infection or significant comorbidity, and no involvement of bone, joint, or tendon, may be treated on an outpatient basis with 24-hour follow-up. Any patient who does not meet these requirements must be hospitalized for intravenous antibiotics and wound care.
Complications include cellulitis, lymphangitis, septic arthritis, abscess formation, osteomyelitis, and flexor tenosynovitis.
All wounds need to be examined in full flexion and extension to evaluate for tendon injuries.
Clenched Fist Injury. The lacerations in this photograph were sustained from teeth during a fight. Note the subtle black ink stamp across the proximal metacarpals possibly revealing a clue about the wound’s etiology. (Photo contributor: Lawrence B. Stack, MD.)