Isokinetic peak torque and work relationship in the laterally unstable knee

The purpose of this investigation was to assess the relationship between the isometric and isokinetic peak torque (speed of movement 0 degrees, 60 degrees, and 180 degrees/s) and the total work output of multiple contractions (180 degrees/s) of the quadriceps and hamstrings in subjects suffering from a chronic insufficiency of the lateral ligament compartment (LAT) of the knee. At every test speed the Pearson product moment (r) and the Spearman rank (rs) correlation coefficients between the peak torque and total work were highly significant for both muscle groups in the uninjured (r = .87-.97, rs = .86-.93) as well as in the laterally unstable (r = .65-.90, rs = .71-.90) knees. In both knees and in both muscle groups the correlation coefficients increased towards the highest speed of the isokinetic movement, obviously since the total work was registered at that speed. In conclusion, concerning laterally unstable knees the total work analysis may offer little additional information to that attained by more simple measurement, the peak torque analysis.