skin callus

Etiology

• structural defects
  • excessive pronation resulting in excessive pressure on the metatarsal heads
  • hammer toes, subluxation & trauma
  • changes in weight bearing associated with neuropathy
• improper footwear
  • high heels
  • ballet dancers
  • athletes

Pathology

• thickened, hardened stratum corneum
• hyperkeratosis

Clinical manifestations

• pain on weight-bearing
• pruritus
• burning sensation
• circumscribed area of hypertrophied & keratinized skin on plantar surface of foot
  • frequently over bone
  • generally over the metatarsophalangeal joint
• flat papule or plaque at the site of repetitive trauma
• may occur on any area of the forefoot
• soft surfaces are often sites of structural abonormalities

Laboratory

none

Differential diagnosis

• plantar keratosis
• plantar wart (does not occur over metatarsophalangeal joint)

Management

• patient education
  • use of pumice stone
    • may wish to avoid in patients with peripheral neuropathy
  • use of emery board
  • softening callus in a warm soak is helpful
  • diabetics must not damage healthy skin causing the callus to bleed
• office care for painful callus
  • remove area of hyperkeratosis with scalpel
  • use small parallel cuts
  • may be needed every 2-3 months
  • debridement is needed to evaluate for the presence of an ulcer or an abscess that is not visible on the surface of the skin
• prevention
  • proper footwear
  • low-heel, soft-sole shoes
  • insoles or orthotics to relieve friction
  • custom footwear
• padding around pressure points
  • comma-shaped pad or 'cookie' over the metatarsal pad
  • moleskin
• topical keratolytic therapy
  • recalcitrant callus
  • more comonly done on plantar warts
  • diabetic patients should not use keratolytic agent
• referral to podiatrist
  • surgical correction of structural defects
    • malaligned metatarsal head can be corrected
    • other bony prominances can be reduced surgically
    • procedures that will lessen excessive pronation
  • non-surgical intervention
    • debridement for patients with diabetes mellitus, peripheral vascular disease, or rheumatoid arthritis
    • source of metatarsal pads, insoles, molds etc
  • referral for failure of more conservative measures

More general terms

• skin disease (dermatologic disorder, dermatopathy, dermatosis)

More specific terms

• skin corn (clavus)