A healthy 34-year-old woman has had “bunion pain” for 5 years. Her custom-made orthoses alleviate 50% of her pain. On examination, she has severe lateral deviation of the hallux (Figure 208-1), a mildly dorsiflexed second digit, tenderness at the medial prominence, painless first metatarsophalangeal (MTP) range of motion, and a callus under the second metatarsal head. Radiographs (Figure 208-2) show medial angulation of the first metatarsal and lateral deviation of the hallux.

The patient was referred to podiatry for surgical correction of the bunion deformity. After surgery, she was placed in a short-leg cast for 6 weeks. She progressed to a regular shoe over the next month and was encouraged to use the custom-made orthoses for her flatfoot to prevent recurrence of the bunion.

Bunion deformity is characterized by the presence of a medial prominence at the first MTP joint, caused by an abducted hallux and adducted first metatarsal. The deformity causes irritation in a tight shoe and pain in the MTP joint. Initial therapy can be conservative with correction of footwear and padding. Surgical procedures correct the misalignment, rather than shave the medial prominence.

Hallux valgus, hallux abducto valgus, metatarsus adductovarus.

• The prevalence of bunions ranges from 2% to 50%.1
  
• It is far more common in women.

Bunion deformities are caused by multiple factors:

• Genetic and hereditary factors.
  
• Abnormal biomechanics (limb length discrepancy, hypermobility/ligament laxity, flatfoot deformity, malaligned skeletal structures, and ankle equinus).2
  
• Neuromuscular diseases.
  
• Ill-fitting shoes.
  
• Trauma.
  
• Iatrogenic causes.

• Flatfoot.
  
• Family history.
  
• Ligamentous laxity.