Manual therapy is effective in reducing VAS pain scores in patients with osteoarthritis

Abstract

Osteoarthritis (OA) affects more than 30 million American adults over the age of 40. Current physical therapy treatment regimes to treat OA do not always include manual therapy and the efficacy of manual therapy remains controversial. Additionally, pain associated with OA can lead to increased stress and cortisol exposure. Our goal was to determine if manual therapy, in addition to prescriptive exercise and ultrasound, is more effective in reducing OA-associated pain and cortisol exposure as compared to prescriptive exercise and ultrasound alone. We hypothesized that the addition of manual therapy would promote an increased reduction in pain and cortisol. Participants were randomly assigned to either a control group (n=19) receiving ultrasound (US) and prescriptive exercise or to an experimental group (n=24) receiving manual therapy in addition to US and prescriptive exercise over a 6-week treatment period. Outcome measures included change in visual analogue scale (VAS) pain level and change in basal salivary cortisol levels. Participants who received the manual intervention experienced a significantly greater reduction in pain level and this was more evident among women, participants with low or normal BMI scores and participants with affected weight-bearing joints. No correlation between change in pain-level and change in basal cortisol was found. Limitations of this study include the small sample size, the length of the study follow up and extrinsic factors that are difficult to control for including stressors in the environment and timing of medication ingestion as it related to cortisol collection time. Overall our data support the efficacy of manual therapy in a physical therapy plan of care to promote the reduction of OA associated pain.