Web-Based Strengthening Exercise, Physical Activity Improves Pain and Function in Knee Osteoarthritis

older woman, home exercise, yoga, stretching
Deutschland, NRW, Köln, Frau entspannt in Altbauwohnung, Silver Surfer
Researchers evaluated the effects of a web-based strengthening exercise and physical activity program on pain and function in patients with knee osteoarthritis.

In patients with knee osteoarthritis (OA), the use of a self-directed web-based strengthening exercise regimen and physical activity guidance supported by automated behavior-change text messages was found to improve knee function and pain at 24 weeks, according to study results published in JAMA Internal Medicine.

Investigators sought to explore the impact of a web-based program supported by text messages on patients with a clinical diagnosis of knee OA.

The study (Australian New Zealand Clinical Trials Registry Identifier: ACTRN12618001167257) was a participant-blinded, assessor-blinded, parallel, 2-arm, superiority randomized clinical trial, which included participants from communities across Australia between July 2018 and August 2019 via online advertisements and the volunteer database of the Centre for Health Exercise and Sport Medicine. Study inclusion criteria were clinical criteria for OA (age ≥45 years, activity-associated knee pain, and morning knee stiffness for ≤30 minutes); knee pain on most days for 30 months or more; average overall knee pain severity of 4 or more on an 11-point numeric rating scale (NRS) during the previous week; ownership of a mobile phone with available text messaging; home internet access; and the ability to consent, participate, and complete assessments.

Individuals who fulfilled the clinical criteria for knee OA were enrolled in the study; follow-up was at 24 weeks. Participants were randomly assigned in a 1:1 ratio to the intervention group or to the control group. Participants in the control group were provided with access to a custom-built website that included information on OA, as well as on the importance of physical activity and exercise, and those in the intervention group were provided with access to the same information, along with a prescription for a 24-week, self-directed strengthening regimen and guidance on increasing levels of physical activity, which was supported by automated behavior-change text messages that were intended to encourage adherence to exercise.

The primary study outcomes included change in overall knee pain (NRS, 0-10) and difficulty with physical function (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC], 0-68) over 24 weeks. Secondary outcomes included Knee Injury and Osteoarthritis Outcome Score (0-68), sport and recreation function, physical activity, overall improvement, treatment satisfaction, quality of life, and self-efficacy.

Of the 206 eligible participants, 180 (mean age, 60 years; 61% women) completed both of the primary outcome measures at 24 weeks. Individuals who did not complete both primary outcome measures at 24 weeks reported greater use of prior injections, nonsteroidal anti-inflammatory drugs, and oral opioids for the management of their knee pain, as well as increased rates of foot problems at baseline.

Study results at 24 weeks showed that the number of participant-reported knee exercise sessions in the previous week was similar among both groups. However, between-group differences in adherence to knee exercises were observed, as measured by the Exercise Adherence Rating Scale, which significantly favored the intervention group (mean difference, 2.6 units; 95% CI, 0.8-4.4 units; P =.005).

Further, the intervention vs control group exhibited significantly greater improvements in overall knee pain (mean difference, 1.6 units; 95% CI, 0.9-2.2 units; P <.001) and WOMAC physical function (mean difference, 5.2 units; 95% CI, 1.9-8.5 units; P =.002).

Significant differences were reported in the intervention group compared with the control group with respect to the percentage of participants who exceeded the minimal clinically important improvement in pain (72.1% vs 42.0%, respectively; risk difference, 0.30; 95% CI, 0.16-0.44; P <.001) and physical function (68.0% vs 40.8%, respectively; risk difference, 0.27; 95% CI, 0.13-0.41; P <.001).

A major limitation of the current study included the potential for bias, with the participants self-selecting to volunteer for a study that evaluated different digital resources to support the management of knee OA, possibly leading to the inclusion of individuals with more favorable views of technology.

Researchers concluded that the use of “this unsupervised, free-to-access intervention could be an effective option for improving patient access to recommended OA exercise and supporting clinicians in providing exercise management to people with knee OA at scale across the population.”


Nelligan RK, Hinman RS, Kasza J, Crofts SJC, Bennell KL. Effects of a self-directed web-based strengthening exercise and physical activity program supported by automated text messages for people with knee osteoarthritis: a randomized clinical trial. JAMA Intern Med. Published online April 12, 2021. doi:10.1001/jamainternmed.2021.0991