Cost-Effectiveness of Nonpharmacologic, Nonsurgical Interventions for Hip and/or Knee Osteoarthritis: Systematic Review

This systematic review published in Value in Health in 2012 investigated the cost-effectiveness of conservative interventions for hip and knee osteoarthritis, a condition that affects millions of people worldwide and represents a substantial public health burden. The authors conducted a comprehensive search across multiple databases through October 2010, including Medline, Embase, PubMed, and other specialized sources, identifying 1,287 potentially relevant articles. After rigorous selection criteria, 11 studies were included that met the established standards for economic analysis based on randomized or quasi-randomized clinical trials. The methodologic protocol used the Quality of Health Economic Studies (QHES) instrument to assess the quality of economic analyses, setting a threshold of 75 points to classify studies as high-quality.

In parallel, the authors applied internal validity criteria recommended by the Cochrane Collaboration Back Review Group to assess the risk of bias of the underlying clinical trials. The analysis revealed considerable heterogeneity across the interventions evaluated, including exercise programs, acupuncture, rehabilitation programs, and lifestyle interventions. The most promising results emerged from the exercise program studies, where all three studies evaluated demonstrated that the interventions resulted in cost savings while delivering better health outcomes. Specifically, a class-based exercise program for patients with knee osteoarthritis, supervised by senior physical therapists, proved superior to home exercise alone in both cost and effectiveness.

Similarly, aquatic therapy and combined aerobic and resistance exercise programs demonstrated favorable cost-effectiveness ratios. The single acupuncture study included in the analysis showed encouraging results, with an incremental cost of $25,707 per quality-adjusted life year (QALY), a value considered acceptable by conventional cost-effectiveness standards that set $50,000 per QALY as the threshold. The treatment involved needle acupuncture with manual stimulation performed by certified physicians, with the number of needles and points determined by clinical judgment. Rehabilitation programs showed contradictory results, with some studies showing QALY losses despite reduced costs.

The behavioral graded activity program, although it resulted in savings of $63,000 per QALY lost, raises questions about the interpretation of cost-effectiveness when health outcomes worsen. Lifestyle interventions, including educational and self-management programs, generally did not demonstrate adequate cost-effectiveness when QALYs were used as the benefit measure. However, some of these programs showed significant improvements on specific scales such as WOMAC, suggesting clinical benefits that may not have been fully captured by quality-of-life measures. A critical limitation identified was that 6 of the 11 studies presented a high risk of bias for cost and/or effectiveness components, compromising the reliability of their estimates.

Additionally, 6 studies used comparators of unknown cost-effectiveness, limiting the ability to determine whether the new interventions actually improve overall efficiency of health care spending. The clinical implications suggest that, although international guidelines recommend conservative treatments as first-line therapy for osteoarthritis, the cost-effectiveness evidence remains limited. Exercise programs emerge as the most promising option, offering the best cost-benefit ratio for conservative management of hip and knee osteoarthritis. Acupuncture, based on limited but high-quality evidence, may represent a cost-effective option for selected patients.