Rehab after TKR Needs to Kick Up the PaceSo it's been a year since you had a total knee replacement (TKR), and your leg strength still isn't what it should be. Join the club. Researchers confirm that despite decreased pain and increased motion after TKR, walking and stair climbing speeds are reduced by 50 percent compared to normal adults in the same age range.
Knee pain doesn't seem to be the problem. Weakness of the quadriceps muscle is the main problem. The quadriceps muscle along the front of the thigh straightens the knee. Muscle activation and atrophy account for 85 percent of the change in quadriceps strength. Failure to voluntarily contract muscle fibers seems to be the biggest problem.
But if pain isn't causing failure of the muscles to contract, what is? Researchers aren't sure. Until this mystery is solved, they suggest the rehab program should focus on improving quadriceps muscle activation as early as possible after surgery.
More studies are needed to find out which rehab program is best. High-intensity muscle contractions may be the best way to start. Biofeedback and neuromuscular electrical stimulation may also help improve quadriceps strength.
Ryan L. Mizner, MPT, PhD, et al. Early Quadriceps Strength Loss after Total Knee Arthroplasty. In The Journal of Bone and Joint Surgery. May 2005. Vol. 87-A. No. 5. Pp. 1047-1053.