Therapeutic Exercise May Benefit Specific Populations With Osteoarthritis

Patients with higher levels of osteoarthritis (OA)- related pain and disability may benefit from therapeutic exercise, according to results of a systematic review published in Lancet Rheumatology.

To combat the rising incidence of knee and hip OA worldwide, several organizations (American College of Rheumatology/Arthritis Foundation, Osteoarthritis Research Society International) have recommended therapeutic exercise as a core treatment. Systematic reviews have cited exercise as beneficial for pain and physical function. However, observed benefits were shown to decline over time, with only half of participants achieving treatment response. Researchers aimed to assess the overall effects of exercise among patients with OA and identify individual-level characteristics that may affect outcomes related to pain and physical function. 

A systemic review and individual participant data meta-analysis was conducted from March 2012 to February 2019. Data were extracted from randomized controlled trials (RCTs) comparing the effects of therapeutic exercise vs no/different forms of exercise on pain and physical function in patients with knee and/or hip OA.

The primary outcomes of interest were short term (12 weeks), medium term (6 months) and long term (12 months) effects of exercise in relation to self-reported pain and physical function. Twelve moderators (individual characteristics) were also assessed in relation to the primary outcomes. Pain was measured on a standardized 0-100 scale, with a score of 100 corresponding with the worst pain.

A total of 31 RCTs comprised of 4241 patients were included in the final analysis. Eighteen studies evaluated patients with knee OA, 6 with hip OA, and 7 with mixed knee and hip OA. Across all studies, mean baseline patient pain score was 39.7. Median baseline physical function score was 36.8. 

Overall, relative to the non-exercise-controlled conditions, therapeutic exercise was found to reduce pain by 6.36 points in the short term, 3.77 points in the medium term, and 3.43 points in the long term.

Physical function showed similar results when compared with non-exercise-controlled conditions. Exercise improved physical function with a difference of -4.46, -2.71, and -3.39 points in the short, medium, and long term, respectively.

Among the 12 moderators that were assessed, baseline pain severity and physical function were shown to moderate the effects of exercise. Patients that reported more severe pain and worse physical function at baseline benefitted more from exercise compared against those with less severe pain and better physical function. Results of this moderation were more prevalent in the short term. The additional 10 moderators did not alter the benefits of therapeutic exercise.

This study was limited by heterogeneity among the RCTs included in the analysis. Additionally, as individual patient data was only obtained from 40% of eligible trials, bias may be present in study results.

The researchers stated, “Although our findings question the magnitude of expected therapeutic benefit from exercise in people with knee, hip, or mixed osteoarthritis, we acknowledge that exercise is unlikely to be harmful and can have multifaceted benefits for general health and for comorbid conditions, irrespective of osteoarthritis.”

“Targeting individuals with higher levels of osteoarthritis-associated pain and disability for exercise therapy might therefore be of merit,” they concluded.

 Disclosures: Some study authors declared affiliations with biotech, pharmaceutical, or device companies. Please see the original reference for a full list of disclosures.