A comparison of isokinetic strength testing and gait analysis in patients with posterior cruciate-retaining and substituting knee arthroplasties

Fourteen patients with a posterior-stabilized prosthesis in one knee and a posterior cruciate-retaining prosthesis in the contralateral knee and both scoring good or excellent on the Hospital for Special Surgery (HSS) knee sc ale were evaluated by isokinetic muscle testing and comprehensive gait anal ysis at a mean follow-up of 98 months after arthroplasty. The average HSS k nee score (93 points) and the average Knee Society score (94 points) were t he same for the cruciate-retaining and posterior-stabilized knees. No diffe rences were noted between the cruciate-retaining and the posterior stabiliz ed knees with respect to isokinetic muscle testing parameters (peak torque, endurance, angle of peak torque, and torque acceleration energy) for both quadriceps and hamstrings. No significant differences were found between th e cruciate-retaining and the posterior-stabilized knees with regard to gait parameters, knee range of motion, and electromyographic waveforms during l evel walking and stair climbing. Cruciate-retaining and posterior-stabilize d total knee prostheses perform equally well during level gait and stair cl imbing.