Effectiveness of Manual Physical Therapy and Exercise in Osteoarthritis of the Knee

BACKGROUND: Few investigations include both subjective and objective measurements of the effectiveness of treatments for osteoarthritis of the knee. Beneficial interventions may decrease the disability associated with osteoarthritis and the need for more invasive treatments. OBJECTIVE: To evaluate the effectiveness of physical therapy for osteoarthritis of the knee, applied by experienced physical therapists with formal training in manual therapy. DESIGN: Randomized, controlled clinical trial. SETTING: Outpatient physical therapy department of a large military medical center. PATIENTS: 83 patients with osteoarthritis of the knee who were randomly assigned to receive treatment (n = 42; 15 men and 27 women [mean age, 60 +/- 11 years]) or placebo (n = 41; 19 men and 22 women [mean age, 62 +/- 10 years]). INTERVENTION: The treatment group received manual therapy, applied to the knee as well as to the lumbar spine, hip, and ankle as required, and performed a standardized knee exercise program in the clinic and at home. The placebo group had subtherapeutic ultrasound to the knee at an intensity of 0.1 W/cm2 with a 10% pulsed mode. Both groups were treated at the clinic twice weekly for 4 weeks. MEASUREMENTS: Distance walked in 6 minutes and sum of the function, pain, and stiffness subscores of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). A tester who was blinded to group assignment made group comparisons at the initial visit (before initiation of treatment), 4 weeks, 8 weeks, and 1 year. RESULTS: Clinically and statistically significant improvements in 6-minute walk distance and WOMAC score at 4 weeks and 8 weeks were seen in the treatment group but not the placebo group. By 8 weeks, average 6-minute walk distances had improved by 13.1% and WOMAC scores had improved by 55.8% over baseline values in the treatment group (P < 0.05). After controlling for potential confounding variables, the average distance walked in 6 minutes at 8 weeks among patients in the treatment group was 170 m (95% CI, 71 to 270 m) more than that in the placebo group and the average WOMAC scores were 599 mm higher (95% CI, 197 to 1002 mm). At 1 year, patients in the treatment group had clinically and statistically significant gains over baseline WOMAC scores and walking distance; 20% of patients in the placebo group and 5% of patients in the treatment group had undergone knee arthroplasty. CONCLUSIONS: A combination of manual physical therapy and supervised exercise yields functional benefits for patients with osteoarthritis of the knee and may delay or prevent the need for surgical intervention.