Felon

Background

• Subcutaneous pyogenic infection of the pulp space compartments of the distal finger
• Do not mistake for pulp erythema due to paronychia or herpetic whitlow
• Infection typically begins w/ minor trauma to dermis overlying finger pad
  • May spread to flexor tendon sheath, IP joint, or underlying periosteum

• The inciting event is often a foreign body such as a splinter

Clinical Features

Felon

• Red, tense, and markedly painful distal pulp space

Diagnosis

• Gram stain and culture (chronic infections may be caused by atypical organisms)

Differential Diagnosis

Hand and finger infections

• Bed bugs
• Closed fist infection (Fight Bite)
• Hand cellulitis
• Hand deep space infection
• Hand-foot-and-mouth disease
• Herpetic whitlow
• Felon
• Flexor tenosynovitis
• Paronychia
• Scabies
• Sporotrichosis

Look-Alikes

• Digital mixoid cyst

Workup

• Xray to assess for foreign body

Treatment

Incision and drainage

Incision of felon.

• The incision should be made along the ulnar aspect of the index, middle, and ring fingers and along the radial aspects of the thumb and little finger.
• Number 11 blade is used to make incision on nonoppositional side of affected digit
• Start incision 5 mm distal to flexor DIP crease
• End incision 5mm proximal to nail plate border
• Bluntly dissect and explore wound until abscess is decompressed

no need for packing

Complications

DO NOT perform a "fishmouth" incision since it results in an:

• Unstable finger pad
• Neuroma
• Loss of Sensation

Disposition

• Instruct pt to keep extremity elevated
• Antibiotics indicated for felons associated with cellulitis
• Dispo with followup in 2 days for wound check
• Ortho only if complications

See Also

• Hand and finger infections

Source

• Clark, DC. Common Acute Hand Infections. Am Fam Physician 2003;68:2167-76