Foot & ankle for FRCS (Tr & Orth)

What the paper tends to test

• Hallux valgus questions give the radiographic angles and the state of the first metatarsophalangeal and tarsometatarsal joints, and ask which type of procedure fits.
• Flatfoot questions are staged: is the hindfoot deformity flexible or rigid, can the patient perform a single-leg heel raise, and is the ankle involved?
• Cavus foot questions test the Coleman block test and the search for a neurological cause.
• Diabetic foot questions ask you to separate Charcot neuroarthropathy from infection and to know the principles of offloading.
• Ankle arthritis questions ask for the factors that favour fusion or replacement, and the position in which an ankle is fused.

Classic traps and discriminators

• The Coleman block test shows whether hindfoot varus is driven by a plantarflexed first ray: if the heel corrects to valgus with the first ray hanging off the block, the hindfoot is flexible and the deformity is forefoot-driven.
• A unilateral or rapidly progressive cavus foot is not assumed to be idiopathic: it needs a neurological examination and imaging of the spine.
• In an acutely hot, swollen, neuropathic foot with intact skin, Charcot neuroarthropathy is more likely than osteomyelitis; diabetic foot infection almost always begins from an ulcer.
• An arthritic first metatarsophalangeal joint with hallux valgus is treated by fusion, not by a realignment osteotomy.
• An Achilles tendon rupture is diagnosed clinically — a palpable gap and absent plantarflexion on calf squeeze — and active plantarflexion can be preserved by the other flexors, so its presence does not exclude rupture.

Foot & ankle questions, answered