Analgesic Use in Hip, Knee Osteoarthritis Reduced After Exercise Therapy

Man exercising his knee
Man exercising his knee
Analgesic use in patients with knee and hip osteoarthritis significantly reduced after supervised exercise therapy.

Analgesic use among patients with knee and hip osteoarthritis (OA) was found to be reduced after supervised exercise therapy and patient education, according to results of an observational study published in the British Journal of Sports Medicine.

Researchers aimed to investigate changes in analgesic use, including paracetamol, nonsteroidal anti-inflammatory drugs (NSAIDs), and opioids, before and after an 8-week supervised exercise therapy and a patient education program in patients with knee or hip OA.

The retrospective cohort study included data from the Good Life with Osteoarthritis in Denmark (GLA:D) registry from January 2013 to August 31, 2017. Inclusion criteria for the GLA:D registry were patients with joint problems from the knee and/or hip that resulted in contact with the healthcare system. The GLA:D intervention consisted of 2 to 3 sessions of patient education provided by a trained physiotherapist and 12 sessions of supervised neuromuscular exercise therapy delivered twice weekly for 60 minutes over a 6-week period. Analgesic use was assessed by the treating physiotherapist at baseline, with a focus on the use of paracetamol, NSAIDs, and opioids. Pain intensity in the index joint within the previous month was patient-reported by a visual analog scale (VAS; 0-100 mm).

A total of 16,499 of the 25,933 eligible patients (64%; mean age, 64.9±9.6 years; 73% women) who met the criteria and participated in clinical follow-up were included in the study. Study results showed a reduction in the percentage of all analgesic users from 62.2% (95% CI, 61.5%-63.0%) at baseline to 44.1% (95% CI, 43.3%-44.9%) at follow-up. Absolute change was 18.1% (95% CI, 17.3%-19.0%), with a relative reduction of 29%. Analgesic use reduction was mainly caused by 36% relative reduction in the number of NSAID users, with an absolute change of -12.2% (95% CI, -13.0% to -11.5%).

Decreased analgesic use was similar among patients with knee (n=12,324) and hip OA (n=4175), despite patients with hip vs knee OA having a higher relative use of analgesics at baseline and clinical follow-up. Among patients with analgesic use at baseline, 52% changed to a lower risk analgesic or discontinued analgesic use; however, a large group (46%) also continued using the same analgesic at clinical follow-up.  On average, VAS pain improved 13.2 mm (95% CI, 12.8-13.6 mm) from baseline to follow-up in 14,087 study participants. Patients who stopped using analgesics reported the largest reductions in pain (improvement, 21.0 mm; 95% CI, 20.3-21.6 mm).

Study limitations included the retrospective assessment by a physiotherapist resulting in an inherent risk for recall bias, a potential social desirability risk bias, and the lack of information about dose and frequent of analgesic use.

“These data encourage [randomized controlled trial] evaluation of whether supervised exercise therapy in combination with patient education can reduce analgesic use, including opioid use, among patients with knee and hip OA pain,” the researchers concluded.


Thorlund JB, Roos EM, Goro P, Ljungcrantz EG, Grønne DT, Skou ST. Patients use fewer analgesics following supervised exercise therapy and patient education: an observational study of 16499 patients with knee or hip osteoarthritis. Published online September 21, 2020. Br J of Sports Med. doi:10.1136/bjsports-2019-101265