Hand-held dynamometer identifies asymmetries in torque of the quadriceps muscle after anterior cruciate ligament reconstruction.

Abstract

Purpose: To verify the validity and diagnostic accuracy of the hand-held dynamometer (HHD) with the isokinetic dynamometer for evaluating the quadriceps strength of subjects who have undergone ACL reconstruction (ACLR).

Methods: This validity and diagnostic accuracy study was conducted prospectively by examining 70 consecutive participants who had undergone ACLR at least 6 months previously. All participants performed strength evaluation of the quadriceps muscle using the HHD and isokinetic dynamometer.

Results: The HHD presented high test-retest reliability [intraclass correlation coefficient (ICC) = 0.98], moderate to good validity with the isokinetic dynamometer when compared for the quadriceps strength (r = 0.62), 100% perfect specificity [LR + infinity, 95% confidence interval (CI) 81.4%-100%] to identify those with LSI > 10%, and a sensitivity of 63.4% (48.9%-76.3%).

Conclusion: The HHD is an instrument valid and reliable of low cost and easy handling compared to the isokinetic dynamometer to evaluate the quadriceps torque and the limb symmetry index after the ACLR with high diagnostic accuracy.

Level of evidence: I.