Fingertip pulp is divided into numerous small compartments by vertical septa that stabilize the pad. Infection occurring within these compartments can lead to abscess formation, edema, and rapid development of increased pressure in a closed space. This increased pressure may compromise blood flow and lead to necrosis of the skin and pulp.
Wooden splinters, thorns, or minor cuts are common predisposing causes, yet no history of injury exists in over one half of patients. Infection also may spread from a paronychia.
The infection often begins as cellulitis, which is initially confined by the tough fibrous septa that course throughout the pad. At this stage, patients may report pain, redness, and swelling. Mild infections may resolve with antibiotics.
If resolution does not occur, abscess formation is accompanied by progression of swelling and intense throbbing pain.
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Adequate early treatment of a felon can prevent abscess formation and other serious complications.
Administer antibiotics with activity against methicillin-resistant Staphylococcus.
Decompression is essential to preserve blood flow, whether or not a frank abscess has formed.
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