Extensor strength in the anterior cruciate reconstructed knee.

Truncated range average torque (TRAT), peak torque (PT) and angle of peak torque (APT) in the knee extensor musculature of subjects with patellar tendon autograft anterior cruciate ligament reconstructions were compared with non-operated limbs two to four years following surgery. Twenty subjects were assessed using a Kin-Com 500H isokinetic dynamometer at three velocities for both concentric and eccentric muscle actions. Results of TRAT for the knee extensors showed average concentric and eccentric deficits of 8.48 per cent and 6.73 per cent, respectively. Deficits in PT were 8.26 per cent concentrically and 7.96 per cent eccentrically. There was no difference in the APT for each action or velocity. Despite an accelerated rehabilitation program, significant residual deficits were evident. Continued strengthening of the knee extensor muscles is recommended.