During a recent PW Podcast episode, Ewa Roos, PhD, a professor of musculoskeletal function and physiotherapy at the University of Southern Denmark, talked about changes in outcomes among patients with knee or hip osteoarthritis (OA). The following includes highlights from that interview.

What was the reason behind your study?

Clinicians who treat patients with osteoarthritis share a common perception that patients with knee osteoarthritis (OA) have better outcomes from exercise than those with hip OA, which may have to do with anatomical differences, such that the muscles in the knee are suspected of playing a greater role in stabilizing joints than those in the hips. As a result, clinicians may prioritize recommending an exercise program for patients with knee OA over patients with hip OA to treat their symptoms. However, results of the few studies assessing this topic were inconclusive.

How did you set out to conduct your research?

We utilized the large Good Life with osteoArthritis in Denmark (GLA:D) database in which outcomes are collected prospectively from patients with knee and hip OA treated with education and exercise therapy. A total of 24,241 patients with knee OA and 8,358 patients with hip OA were included. Among the variables we compared were changes in pain intensity, knee injury/hip disability scores, QOL, and results of 40-meter walk tests at 3 and 12 months.

What were your key findings?

Patients with knee OA and hip OA were on average more alike in outcome than different. Symptom duration, pain intensity, use of pain medication, physical function, and QOL were similar in both groups. Over time, improvements were found in both groups and any differences in outcome between them were insignificant. We observed more obesity among patients with knee OA than among those with hip OA. In addition, more patients with knee OA presented with bilateral symptoms. We found that symptoms in the hips of patients with knee OA were less common than symptoms in the knees of patients with hip OA. In patients with knee OA, previous injury and surgery were far more common than in those with hip OA.

What would you like to see explored in future research on this topic?

We have sufficient data to know that exercise therapy works well for both groups of patients, and that exercise therapy is a cornerstone for the treatment of OA in all available clinical guidelines. The mystery is why this treatment is not taken seriously or sufficiently implemented.