PLANTAR PRESSURES AND TROPHIC ULCERATION

Abstract

1. With the object of perfecting the design of footwear for feet anaesthetic from leprosy, pressures on the soles of feet during walking were measured with transducers sufficiently thin to be worn inside ordinary shoes. 2. It was found that anaesthetic feet without deformity or muscle imbalance did not produce significantly higher pressures than normal feet during barefoot walking on a flat surface. The pressure distribution under drop feet with active posterior tibial muscles differed from normal, with increased pressure under the lateral forefoot and decreased pressures elsewhere. 3. Loss of toes or function of the toes results in high, sharp pressure peaks under the anterior end of the foot during push-off. In deformed feet these pressures are usually concentrated at one or two small areas. 4. In anaesthetic feet the prevention of trophic ulceration largely depends on the even distribution of pressure over the sole of the foot. 5. Moulding by carefully placed arch supports or metatarsal bars effectively redistributes plantar pressure. 6. A shoe with a rigid sole pivoting on a rocker near the centre of the foot most effectively reduces pressures under the forefoot of shortened, deformed feet. 7. We recommend the use of insoles made of microcellular rubber (approximately 1 5 degrees shore). 8. The importance of studying each deformed foot for areas of high pressure before fitting shoes is stressed; a pressure-indicating footprint is satisfactory for this purpose.