Exercise as Medicine During the Course of Hip Osteoarthritis

Inger Mechlenburg; Lisa Cecilie Urup Reimer; Troels Kjeldsen; Thomas Frydendal; Ulrik Dalgas


Exerc Sport Sci Rev. 2021;49(2):77-87. 

In This Article

Exercise as Secondary and Tertiary Prevention in Mild to Moderate Hip OA

In patients with mild hip OA, pain is present during hip movements, whereas muscle strength, hip range of motion, and walking speed are impaired compared with healthy individuals.[75] These symptoms result in limitations in activities of daily living and have negative impact on QoL.[76] Consequently, symptomatic treatment modalities in mild-moderate hip OA should aim at improving these deficits. Currently, it is recommended that conservative nonpharmacological treatments should be included as a first-line strategy for the initial management of hip OA.[77] Importantly, the effectiveness of exercise as a conservative treatment for mild hip OA has become well established during the last decade.[43,44,78,79] A meta-analysis by Goh et al.[78] found that all types of exercise (aerobic, strengthening, mind-body, flexibility, and mixed) were significantly better than usual care for pain and patient-reported and performance-based function in people with hip OA. They also found that exercise was more beneficial among participants who were not awaiting joint replacement compared with those who were.[79] Furthermore, a Cochrane review and meta-analysis published in 2014 reported high-level evidence supporting the effectiveness of land-based exercise as a means to reduce pain and improve physical function in people with symptomatic hip OA.[43] Moreover, the Ottawa Panel recommends land-based exercise, notably strength training, to reduce pain, stiffness, and self-reported disability and for improving physical function in hip OA.[80] Further supporting the role of exercise in mediating pain, a meta-analysis found that exercise, land based or water based, is effective for reducing pain in the short term among patients with hip OA.[44] However, this effect was not found in studies applying medium- to long-term follow-up.[44] In agreement with these findings, the aforementioned meta-analysis by Goh et al.[79] found that the beneficial effects of exercise interventions for patients with hip OA generally peak around 2 months and then gradually decrease until they are no better than people receiving usual care at the 9- to 18-month follow-up. This may reflect that the evaluated exercise interventions are either too short or that persons with hip OA tend to stop exercising after the (often short) exercise intervention. However, the Cochrane review found no effect on QoL, seemingly due to sparse evidence with only three low-quality studies investigating this outcome.[43] Since the review was published, Krauß et al.[45] conducted a randomized controlled trial (RCT) investigating the effect of exercise on pain, patient-reported function, and QoL. They compared 12 wk of neuromuscular exercise and education with ultrasound placebo treatment and a no-intervention control group in patients with clinically diagnosed hip OA who had moderate functional limitations. Despite observing superior results for the exercise group on the primary outcome, the Short Form-36 pain subscale, no effects on general health-related QoL was found. As the study population in this study had a better score on the general health subscale of the Short Form-36 compared with the normative German population, the general lack of QoL improvements across the literature, therefore, may be explained by only minimal impairments of this domain in the existing studies.

It is still unclear what the optimal exercise modality is for patients with mild to moderate hip OA. The meta-analysis by Goh et al. that included both knee and hip OA found that mixed exercise was the least effective modality for all outcomes, whereas aerobic exercise and mind-body exercise were superior at improving pain and performance-based function.[78] Strengthening and flexibility exercise improved multiple outcomes at a moderate level, yet these findings may be biased by the included knee OA studies, and it subsequently remains to be established in data solely from hip OA. Bieler et al.[81] conducted an RCT in 152 patients with hip OA comparing 4 months of either supervised Nordic walking, or supervised resistance training, or home exercise. The improvement in the primary outcome, the 30-s sit-stand test, was largest in the Nordic walking group. This result may be influenced by a high drop-out rate in the Nordic walking group and an inefficient resistance training intervention showing no improvement in muscle strength. Another RCT in women with hip OA compared home-based resistance training performed at either high or low velocity using elastic bands, showing no between-group differences in the improvements of muscle strength, and only one of their performance-based tests, the Timed Up and Go test, showed a superior improvement in the high-velocity group.[82]

To summarize, exercise may offer tertiary prevention in patients with mild to moderate hip OA in terms of pain reduction and improved physical function, whereas no evidence supporting secondary prevention could be located. In addition, the optimal exercise modality remains to be elucidated.