Abstract
The aim of this study was to determine if a deficit existed in the truncated range average torque (TRAT) values of the knee extensor muscles of the operated limb in subjects with patellar tendon autograft anterior cruciate ligament reconstructions when compared with the non-operated limb at 12 and 18 weeks following surgery. Subjects were assessed using the Kin-Com (500 H) dynamometer utilising a proximal pad to reduce shear force through the tibio-femoral joint. Three isokinetic velocities (60, 120 and 180 deg/sec) for concentric and one velocity (60 deg/sec) for eccentric muscle actions were tested. Results of the TRAT for knee extensors showed average concentric deficits of 25.4% at 12 weeks and 17.6% compared to the non-operated limb on both testing occasions. There was a significant improvement of TRAT scores of the operated limb from 12 to 18 weeks for all testing velocities except 120 deg/sec. The results of this study not only provide quantitative values of knee extensor strength deficits at 12 and 18 weeks post-surgery but also indicate a significant improvement in knee extensor strength of the operated limb over the same time period. This confirms both the large strength deficits and improvements in strength which clinicians have long suspected exist at this early stage following reconstructive surgery.