Physical training reduces pain – even in severe knee osteoarthritis

Patients with severe Osteoarthritis (OA) benefit from a combination of optimisation of analgetics and a physical training program.

Improvement in all endpoints

Patients with severe Osteoarthritis (OA) benefit from a combination of optimisation of analgetics and a physical training program.

“We have a high quality evidence from 44 trials including over 3536 patients with OA that an exercise program can reduce pain in a moderate effect size”, says Marike van der Leeden, Department of Rehabilitation Medicine, VU University Medical Center, Amsterdam (the Netherlands). However, most trials included only patients with mild to moderate OA.

The mode of action responsible for this pain reducing effect is not entirely clear: It is probably a combination of physiologic factors such as an increase in muscle strength and improvement of proprioception and psychosocial factors such as a general increase in well being or a decrease of depressive factors. In addition, exercise has an anti-inflammatory effect, and inflammation is considered to be a key feature of knee OA.

“Although we know that exercise decreases pain, particularly patients with severe OA fear pain, which may hamper their ability to engage in an exercise program”, explains van der Leeden.
This was the rationale to test the efficiency of a combination of analgetics and an exercise program to reduce OA pain. “By optimizing medication we allowed patients to participate in the program”, explained van der Leeden. The optimisation followed a certain protocol, the first step being paracetamol followed by increasingly intensive regimen (according to WHO and Bart). When the pain on a numerical rating scale (NRS) was ≤ 5 the exercise program was started with increasing intensity over 12 weeks.

Measurements of OA pain were performed at baseline, after the medication phase and after completion of the physical training program. Although 95% of patients took paracetamol, only in 39% of patients a painscore of ≤ 5 could be reached before the start of the exercise program. “Many patients were not willing to do the next step in the pain protocol, others had contraindications”, explained van der Leeden this result. However, 78% of patients were still able to perform the training program.

After completion of the analgetic phase, an improvement could be demonstrated in all outcome measures (pain and physical functioning). During the exercise phase, there was a further 17% improvement in physical functioning and a staggering 30% improvement in the pain on NRS.
Patients who were not able to participate in the training program had more severe radiological symptoms or a comorbidity of anxiety and depression. “In these group our approach is not recommendable, they might benefit from a different program”, concludes van der Leeden. The trial shows however, that by optimizing medical therapy, even patients with severe OA can take part and benefit from a physical training program.

1. Van der Leeden M. Exercise therapy to reduce pain in knee osteoarthritis: mechanism and treatment optimization. Abstract SP0016, presented on the 10th of June.
2. 2016 Annual EULAR Meeting