The biomechanical effects of talectomy on the foot.

ABSTRACT

The biomechanical effects of talectomy on the foot were investigated in seven fresh below-the-knee amputation specimens using pressure-sensitive films placed on the facets of the calcaneus, footprints, and loading-pattern diagrams in the intact foot and after talectomy with anterior and posterior displacement of the foot. Both talectomy techniques distorted the loads carried by the facets of the calcaneus. In the intact foot, 65.6% of the loads were carried by the posterior facet of the calcaneus and 34.4% by the anterior and middle facets. After talectomy with anterior displacement of the foot, although the loads carried by the anterior and middle facets decreased significantly (P = .018), the increase in the loads carried by the posterior facet was not significant compared with the intact foot (P = .176). Similarly, the loads carried by the posterior facet decreased significantly after talectomy with posterior displacement of the foot (P = .028), but the increases in the loads carried by the anterior and middle facets were not significant (P = .735). Comparing the two types of talectomy, the loads carried by each facet changed significantly (P = .018). Talectomy with posterior displacement of the foot also changed the loading patterns and resulted in significant pronation of the foot. These results suggest that talectomy should be performed only as a salvage procedure and that talectomy with anterior displacement of the foot may be preferred when talectomy is indicated.