Aeitiology

1. Unknown
2. Increased incidence in
   • Familial clusters
   • people who wear enclosed footwear
   • Associted with rheumatoid arthritis
   • secondary to metatarsus primsu varus 

Approach

• Expose both ankles and feet
• Kneel in front of the patient

1. Look

   

   • Unilateral / bilateral?
   • Estimate degree of valgus
   • Rotation of nail?
   • Bunion? (prominence of medial aspect of 1st MT head with or without and underlying bursa)
   • Signs of inflammation of bursa?
   • Hammered or retracted toe?
   • Look at soles of feet ?callosities present
2. Feel
   • Inflammation of bunion
   • Localised tenderness
3. Move
   • Assess range of movement of MTPJ
   • Note any hypermobility (indicates instability)

Completion

1. Assess range of motion of other toes
2. Gait assessment - allows inspection of heel and ankle from the back
3. Examine shoes - reflected in pattern of wear
4. Ask how condition affects life

Investigations

• Weightbearing X-rays

1. degree of valgus deformity
2. First / second intermetatarsal angle (IMA) and distal metatarsal articular angle
3. Presence of OA of first MTPJ

Treatment options

1. Non-surgical
   • Appropriate footwear - wide shoe, soft upper wide toe box and protective padding
   • Physiotherapy
2. Surgical
   • Bunionectomy
   • First metatarsal realignment osteotomy
   • Excision arthroplasty (Kellers' procedure)
   • Fusion / arthrodesis