Recovery of Contractile Properties of the Knee-Extensor Muscles after Arthroscopic Partial Meniscectomy

Context: Contractile characteristics of the knee extensors after arthroscopic meniscectomy are poorly understood. Objective: To measure the recovery of knee-extensor-muscle contractility after arthroscopic partial meniscectomy. Design: Single-group repeated measures. Setting: Kinesiology and biomechanics laboratory. Subjects: Fourteen patients with arthroscopic partial medial meniscectomies. Main Outcome Measures: Maximal isometric voluntary contraction (MVC) force, rate of force development (MRFDES), and half-relaxation time (HRTES) of evoked tetanic contraction preoperatively and during 6 months postoperatively. Results: Two weeks postoperatively, a reduction in MVC force of 27.1% and in MRFDESof 17.8% and a prolongation of HRTESof 34.0% in the injured leg were found. A significant MVC-force deficit (17.5%) was observed 3 months postoperatively. Conclusions: The recovery of knee-extensor-muscle voluntary strength is more delayed than are evoked tetanic-contractile characteristics after partial meniscectomy. The rehabilitation protocol seems to be insufficient to attain effective recovery of knee-extensor-muscle voluntary strength.