The rheumatoid foot is a whole subject in itself. Ninety per cent of patients with rheumatoid arthritis will have involvement of their feet. This usually affects the metatarso-phalangeal joints of both feet symmetrically. Patients develop hallux valgus deformities with gradual subluxation and dislocation of the lesser toe MTP joints. The usual complaint is the feeling of “walking on pebbles” due to the prominent metatarsal heads.
Treatment is initially by accommodative shoe wear and orthotics. Surgical treatment consists of excision of the metatarsal heads and a realignment and fusion of the great toe MTP joints. This so called forefoot arthroplasty provides excellent symptomatic relief both in the short and long term.
Rheumatoid arthritis can also affect the hind foot classically producing a marked piano valgus deformity. This is managed initially with accommodative shoe wear and orthotics. If this approach fails a triple fusion is often the procedure of choice. In patients with rheumatoid arthritis great care must be taken with the soft tissues and, as in all foot surgery, a careful assessment of the peripheral vascular supply must be taken.