Use of physical therapy and corticosteroid injections in the management of knee osteoarthritis in the U.S. military health system

Abstract

Purpose: The prevalence of osteoarthritis (OA) in active duty military members is much higher than age-matched groups in the general population. OA is one of the most common and costly conditions encountered in military healthcare. Physical therapy management has been shown to result in clinically relevant improvements in pain, function and disability levels in patients with knee OA. However, several studies have shown that in civilian healthcare settings, very few patients with knee OA receive physical therapy treatment. To date, no data exists on the utilization and timing of healthcare services for this population in the military healthcare system. The purpose of this study is to determine the utilization rates and timing of physical therapy services for patients with knee OA in the military healthcare system. Methods: This was a retrospective review of data extracted from the Military Health System Data Repository (MDR) from 2008 to 2013. Patients presenting to a primary care clinic for a knee OA diagnosis without any care for that diagnosis in the preceding 12 months were included in the analysis. The date of diagnosis in the primary care clinic became the "index date" and healthcare utilization was examined for a 12-month period following the index date. Utilization and timing of physical therapy and corticosteroid injections were analyzed for the management of each patient for that 1-year period. Results: There were 135,049 unique patients across the entire MHS that met the criteria during this 5-year period. Within the 1 year of care following diagnosis, 40.0% of patients received a corticosteroid Injection and 29.2% of patients received physical therapy. Only 12.9% of patients received both physical therapy and a corticosteroid injection during their 1-year course of care. Timing of interventions also varied. For corticosteroid injection, 50.9% received a CSI within 30 days of the diagnosis, and 27.5% occurred on the same day as the diagnosis. Conversely, only 29% of physical therapy visits began within 30 days of the diagnosis, and 45% occurred after 90 days. Within the 1-year timeframe, 5.0% underwent arthroscopic surgery and 4.6% underwent knee arthroplasty. Only 8% of patients that underwent arthroplasty and 26% of patients that underwent arthroscopy had physical therapy prior to their respective surgeries. Conclusions: Clinical practice patterns within the MHS do not seem to follow established guidelines for the use of physical therapy. These findings corroborate other findings of poor adherence with guidelines in the civilian healthcare system. When the initial choice for conservative treatment is between a corticosteroid injection or physical therapy, it seems that corticosteroid injection is more frequently chosen. There appears to be underutilization of a trial of physical therapy prior to surgical management for knee OA.