Metatarsal osteotomy for primary metatarsalgia: radiographic and pedobarographic study.

The effect of surgical procedures for primary metatarsalgia on the load distribution and bony architecture of the forefoot is poorly understood. A prospective study was performed on 45 feet with this diagnosis treated by dorsal wedge osteotomy and compared with 29 symptom-free contralateral feet. Each foot was evaluated preoperatively and postoperatively with quantitative radiographic analysis, a pedobarographic study, and by physical examination. Following osteotomy there was a 4.5-mm increase in average height from ground and a 7.0 psi decrease in pressure. The symptom-free control group demonstrated no statistically significant changes. Residual pain occurred with an average height increase of less than 3.5 mm and an average pressure decrease of less than 1.5 psi. Transfer lesions developed in three of four patients with a height increase of greater than 4.5 mm. The symptoms of metatarsalgia are altered by changes in height of the metatarsal or the pressure beneath it. It is not possible to predict the surgical elevation of the metatarsal head required to precisely decrease the pressure beneath the metatarsal head, thereby eliminating symptoms.