MECHANICAL COMPARISON OF BIPLANAR PROXIMAL CLOSING WEDGE OSTEOTOMY WITH PLANTAR PLATE FIXATION VERSUS CRESCENTIC OSTEOTOMY WITH SCREW FIXATION FOR THE CORRECTION OF METATARSUS PRIMUS VARUS

Proximal crescentic metatarsal osteotomy is a clinically successful te chnique for correcting metatarsus primus varus in hallux valgus surger y. However, there have been instances of dorsal elevation of the metat arsal head with this technique. Mechanical testing on 10 matched pairs of cadaver feet was performed to evaluate a new technique combining a biplanar closing wedge osteotomy and plantar plate fixation versus cr escentic metatarsal osteotomy. The specimens were tested in cantilever -bending mode on an MTS Mini Bionix test frame. The mean load-to-failu re values were 127.2 +/- 81.9 N (SD) for biplanar osteotomy with plate fixation and 44.9 +/- 43.3 N for crescentic osteotomy (P = 0.019); th e mean stiffness values at the initial portion of the load-deflection curve were 83.11 +/- 73.76 N/mm and 31.95 +/- 43.00 N/mm, respectively (P = 0.012). The biplanar wedge osteotomy with plantar plate fixation demonstrated significantly stronger fixation than the crescentic oste otomy, with higher mean load-to-failure and stiffness values. this new ly described technique may provide an acceptable alternative for patie nts at risk for dorsal elevation of the metatarsal, particularly those who are noncompliant or have osteopenia. Clinical study will determin e whether this new technique offers satisfactory long-term results.