Progressive Quad Strengthening Enhances Clinical Outcomes post-TKA

Progressive quadriceps strengthening with or without neuromuscular electrical stimulation (NMES) enhances clinical improvement after total knee arthroplasty (TKA), achieving similar short- and long-term functional recovery and approaching the functional level of healthy older adults, says an article published in the February 15 Issue (Vol 61, Issue 2) of Arthritis Care & Research. Conventional rehabilitation does not yield similar outcomes, added the authors, which include APTA members Stephanie Petersen, PT, MPT, Ryan Mizner, PT, MPT, PhD, and Lynn Snyder-Mackler, PT, ScD, SCS, FAPTA.   

A randomized controlled trial was conducted between July 2000 and November 2005 in an academic outpatient physical therapy clinic. Two hundred patients who had undergone primary, unilateral TKA for knee osteoarthritis were randomized to one of two interventions 4 weeks after surgery; 41 patients eligible for enrollment who did not participate in the intervention were tested 12 months after surgery (standard of care group). All randomized patients received 6 weeks of outpatient physical therapy two or three times per week through one or two intervention protocols: an exercise group (volitional strength training) or an exercise-NMES group (volitional strength training and NMES). Treatment effects were evaluated by a burst superimposition test to assess quadriceps strength and volitional activation at 3 and 12 months postoperatively. The Medical Outcomes Study Short Form 36 and Knee Outcome Survey were completed. Knee range of motion, Timed Up and Go, Stair-Climbing Test, and 6-Minute Walk also were measured.

Strength, activation, and function were similar between the exercise and exercise-NMES groups at 3 and 12 months. The standard of care group was weaker and exhibited worse function at 12 months compared with both treatment groups.