Tumors, Infection, and Miscellaneous Hand/Wrist Conditions
Core concepts
Ganglion cyst is the most common hand mass, arising from a joint or tendon sheath. Enchondroma is the most common primary bone tumor of the hand and often presents with pathologic fracture. Giant cell tumor of tendon sheath is a firm, painless nodule; glomus tumor causes cold sensitivity and point tenderness beneath the nail. Malignancy is rare; watch for rapid growth, ulceration, and atypical features such as nail-bed melanoma or squamous cell carcinoma.
Infection is common and occasionally limb-threatening. Paronychia and felon are frequent; flexor tenosynovitis is diagnosed by Kanavel's four signs, namely fusiform swelling, tenderness along the sheath, finger held in slight flexion, and pain with passive extension, and requires urgent irrigation. Necrotizing fasciitis is a surgical emergency. Human bites over the MCP joint, the fight bite, need exploration and antibiotics.
Miscellaneous conditions include Kienbock disease (lunate avascular necrosis, Lichtman staging), De Quervain tenosynovitis (Finkelstein test), trigger finger, and complex regional pain syndrome.
Traps
Treating a fight bite as a simple laceration, mistaking a glomus tumor for paronychia, missing a pathologic fracture through an enchondroma, and attributing a swollen finger to infection when it is inflammatory arthritis are frequent errors.
Rule of thumb
Any hand mass that is not a classic ganglion, or a ganglion recurring atypically, should be imaged or referred before excision; any flexor sheath infection goes to the operating room rather than receiving oral antibiotics alone.