Real-World Use of Manual Therapy and Exercise for Managing Knee Osteoarthritis—A Military Health System Analysis

OBJECTIVES: To (a) describe the health system-level use of exercise and manual therapy for knee osteoarthritis and (b) compare downstream healthcare use between groups that received these interventions. Additionally, to assess the relationship between exercise dose and hazard of undergoing knee arthroplasty. DESIGN: Observational cohort study METHODS: Individuals aged 18-75 years who were diagnosed with knee osteoarthritis between 2013-2017 were grouped by intervention: exercise only, manual therapy only or both. Downstream healthcare use and costs within one year of diagnosis were compared descriptively. Survival analyses examined associations between exercise dose and progression to knee arthroplasty within one year. RESULTS: Of 24,496 eligible individuals, 89.1% (n = 21,820) received no exercise or manual therapy. For the 10.9% (n = 2,676) who received care, 54.3% (n = 1,454) received exercise only, 1.4% (n = 38) received manual therapy only, and 43.2% (n = 1,156) received both interventions. Downstream healthcare use and costs were similar between groups. For each additional exercise visit, there was an 11% lower hazard of knee arthroplasty for those who received exercise only (aHR = 0.89, 95% CI 0.75, 1.05; p = 0.16) and 10% lower hazard for those who received exercise and manual therapy (aHR = 0.90, 95% CI 0.78, 1.04; p = 0.16), but neither were significant. CONCLUSION: Patients rarely received manual therapy without exercise and incurred similar downstream healthcare use compared to patients who received exercise only. Total knee-related costs were similar, regardless of therapy received. Exercise reduced the hazard of knee arthroplasty, but it was not significant.