Chondral Defect Repair After the Microfracture Procedure A Nonhuman Primate Model

BackgroundThe extent and time course of chondral defect healing after microfracture in humans are not well described. Although most physicians recommend a period of activity and weightbearing restriction to protect the healing cartilage, there are limited data on which to base decisions regarding the duration of such restrictions.HypothesisEvaluation of the status of chondral defect repair at different time points after microfracture in a primate model may provide a rationale for postoperative activity recommendations.Study DesignDescriptive laboratory study.MethodsFull-thickness chondral defects created on the femoral condyles and trochlea of 12 cynomolgus macaques were treated with microfracture and evaluated by gross and histologic examination at 6 and 12 weeks.ResultsAt 6 weeks, there was limited chondral repair and ongoing resorption of subchondral bone. By 12 weeks, the defects were completely filled and showed more mature cartilage and bone repair.ConclusionIn the primate animal model, significant ...