The present status of the problem of pes cavus

Notable historical aspects relating to the etiology and treatment of pes cavus have been critically examined. The characteristic features of the deformity are described and an explanation offered for the mechanism of their production. Although its etiology remains uncertain, a study of the literature and a great deal of clinical material has established certain well supported conclusions regarding the etiology and pathology of the condition. Certain aspects of cerebral palsy serve to strengthen impressions of earlier authors that the primary center of origin of pes cavus lies somewhere in the central nervous system. Localized foci of partial damage lying adjacent to tracts of nerve cells more seriously affected by a neurological disease could emit irritating stimuli capable of producing degrees of over-action of the invertor muscles varying from obvious spasm to clinically undetectable increase in muscle tone. Biral or other factors which stop short at creating nothing more than such a focus of irration could explain the insidious onset of the deformity in the idiopathic group. Over-action of invertor muscles for one reason or another, including ischemia, is almost certainly responsible for initiating the deformity, though primary contracture of the plantar fascia could possibly do so. With the appearance of supination of the heel, the calcanean tendon becomes an active invertor adding its force to that of the plantar fascia to produce structural varus of the calcaneum. Contracture of the plantar fascia and supination of the heel are regarded as features of major importance. Correction of the latter can be achieved more effectively by suitable osteotomy than by subtaloid fusion, which is regarded with great disfavor. Conservative treatment consists of exercises and shoe appliances. Surgical correction is based on calcanean osteotomy and plantar fasciotomy supplemented where necessary by suitable tendon transplantations, correction of clawing of the toes, and tarsal or metatarsal wedge resections. Preservation of the midtarsal subtaloid joint complex is essential. With the heel correctly aligned the degree of improvement to be expected in the forefoot deformity is such that any structural operation on it should be deferred until a fair period of walking has been tried.