(See also Overview and Evaluation of Hand Disorders.)
A felon is an infection of the pulp space of the fingertip, usually with staphylococci and streptococci.
The most common site is the distal pulp, which may be involved centrally, laterally, or apically. The septa between pulp spaces ordinarily limit the spread of infection, resulting in an abscess, which creates pressure and necrosis of adjacent tissues. The underlying bone, joint, or flexor tendons may become infected. There is intense throbbing pain and a swollen, warm, extremely tender pulp.
Treatment of felon involves prompt incision and drainage (using a midlateral incision that adequately divides the fibrous septa) and oral antibiotic therapy. Empiric treatment with a cephalosporin is adequate. In areas where methicillin-resistant Staphylococcus aureus (MRSA) is prevalent, trimethoprim/sulfamethoxazole, clindamycin, doxycycline, or linezolid should be used instead of a cephalosporin.