Effect of interposition material on mechanical behavior in partial physeal resection: a canine model.

Abstract

A canine model was used to investigate the mechanical properties of the partially resected physis and the role of load-sharing interposition material. Ten puppy knees were loaded axially, with strain gauges placed across the proximal tibial physis. After partial physeal resections, the knees were retested with and without polymethylmethacrylate (PMMA) in the resection gap. PMMA interposition moderated the change in physeal displacement noted with increasing areas of resection. The Heuter-Volkman law predicts decreased growth in response to increased physeal stress. We therefore recommend use of a load-sharing interposition material in resection of large physeal arrests in weightbearing areas.