Common adult foot deformities
Common adult foot deformities include hallux valgus (bunion), hammertoe, and pes planus or pes cavus, each diagnosed by inspection of the standing, weight-bearing foot and managed first with footwear modification and orthoses before surgery is considered.
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What this article covers
- Overview
Common adult foot deformities are structural malalignments of the forefoot and midfoot that develop over years, most often hallux valgus (bunion), hammertoe, and pes planus (flatfoot) or pes cavus (high arch).
- Epidemiology
Hallux valgus (bunion) is common in adults, particularly women; its cause is not fully established and it occurs even in people who do not wear narrow-toe-box shoes.
- Risk factors
Constricting or narrow-toe-box footwear, a longstanding association with both hallux valgus and hammertoe, although deformity also occurs without this exposure.
- Pathophysiology
Hallux valgus: progressive lateral deviation of the great toe at the first MTP joint with medial displacement of the first metatarsal head produces a medial bony prominence; shoe pressure on the…
- Clinical features
Hallux valgus is recognized on inspection as lateral deviation of the great toe at the first MTP joint with a medial bony prominence, sometimes with overlying erythema; this visual pattern alone…
- Differential diagnosis
Morton neuroma: forefoot pain and paresthesia between the metatarsal heads, most commonly the third web space, with the sensation of walking on a pebble, but without a fixed toe or arch deformity.
- Diagnosis
Common adult foot deformities are diagnosed clinically by inspection of the standing, weight-bearing foot: hallux valgus by visible lateral deviation of the great toe at the first MTP joint…
- Management
First, for all deformities, start with footwear modification: a wide, deep toe box that avoids pressure on the deformity, the single most effective, inexpensive first step.
- Complications
Chronic pain and gait disturbance from an uncorrected fixed deformity altering weight distribution across the foot.
- Prognosis
Most hallux valgus and hammertoe deformities are managed successfully long-term with footwear modification alone, without progression to disability.
- Prevention
A toe box at least as wide as the forefoot, with heel height under 2 inches (5 cm), avoiding narrow, pointed, or high-heeled shoes, reduces progression of hallux valgus and hammertoe.
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