Preoperative Physical Therapy
Limited evidence supports that supervised exercise before total knee arthroplasty (TKA) might improve pain and physical function after surgery.

Rationale
Four high quality studies (Villadsen 2013, Gstoettner 2011, McKay 2012, D’Lima 1996) and four moderate quality studies (Rooks 2006, Topp 2009, Weidenhielm 1993, Brown 2012) compared pre-operative structured exercise program to groups receiving no-exercise, placebo exercise, or education.
 
One study of high quality (Villadsen 2013) and two studies of moderate quality (Topp 2009, Brown 2012) investigated the effects of exercise programs that combined primarily functional training, resistance training, and flexibility exercises compared to not receiving such exercise programs. Villadsen et al compared an exercise program of  eight week duration (1 hour twice a week) supervised by physical therapists that combined warm-up, core stability, postural orientation, resistance training, and functional exercises, to a group who received education on exercise. They reported significantly improved physical function and pain six weeks after surgery, but the differences were no longer significant 3 months after total knee arthroplasty. Topp et al compared an experimental group who received supervised exercise program of four week duration (3 times per week) that combined flexibility exercises, resistance training, and step training, to a group who did not exercise. They reported conflicting results for physical function and pain. At 3 months after total knee arthroplasty the exercise group performed more sit-to-stand repetitions than the control group but the control group ascended stairs faster than the exercise group. The exercise group has less pain during stairs descend but more pain during sit-to-stand task as compared to the control group. Brown et al compared a 8-week (3 session per week) supervised exercise program comprised of warm up, resistance training at moderate intensity, flexibility exercises, and step training, to a control group who did not exercise. They reported better physical function in the exercise group.
 
Two studies of high quality (McKay 2012, D’Lima 1996) and one study of moderate quality (Weidenhielm 1993) evaluated the effects of resistance training primarily. McKay et al compared a group who performed 6 weeks of moderate-intensity strength training of the lower body to a group who did upper body resistance training (placebo). D’Lima designed a three-group study to compare strength training of lower and upper body, aerobic training, and routine care (no exercise). D’Lima was the only study on pre-rehabilitation that had an exercise group who did aerobic training only. Weidenhielm et al compared a 5-week exercise program of knee range of motion and lower body strength training to a group who did not exercise. These studies found no significant differences in outcome between groups. One study of moderate quality (Rooks 2006) et al compared a 6-week exercise program with cardiovascular, strength, and flexibility training to an attention-control group who received education on total knee arthroplasty. Amongst the outcomes evaluated at 8 and 26 weeks after total knee arthroplasty, only bodily pain at 26-week was significantly less in the exercise group. One study of high quality (Gstoettner 2012) demonstrated that 6-week of stretching and balance training was not effective on physical function and pain.