Choice of treatment modalities was not influenced by pain, severity or co-morbidity in patients with knee osteoarthritis.
BACKGROUND AND PURPOSE
Patients with knee osteoarthritis (OA) are commonly treated by physiotherapists in primary care. The physiotherapists use different treatment modalities. In a previous study, we identified variation in the use of transcutaneous electrical nerve stimulation (TENS), low level laser or acupuncture, massage and weight reduction advice for patients with knee OA. The purpose of this study was to examine factors that might explain variation in treatment modalities for patients with knee OA.


METHODS
Practising physiotherapists prospectively collected data for one patient with knee osteoarthritis each through 12 treatment sessions.We chose to examine factors that might explain variation in the choice of treatment modalities supported by high or moderate quality evidence, and modalities which were frequently used but which were not supported by evidence from systematic reviews. Experienced clinicians proposed factors that they thought might explain the variation in the choice of these specific treatments. We used these factors in explanatory analyses.


RESULTS
Using TENS, low level laser or acupuncture was significantly associated with having searched databases to help answer clinical questions in the last six months (odds ratio [OR] = 1.93, 95% confidence interval [CI] = 1.08-3.42). Not having Internet access at work and using more than four treatment modalities were significant determinants for giving massage (OR = 0.36, 95% CI = 0.19-0.68 and OR = 8.92, 95% CI = 4.37-18.21, respectively). Being a female therapist significantly increased the odds for providing weight reduction advice (OR = 3.60, 95% CI = 1.12-11.57). No patient characteristics, such as age, pain or co-morbidity, were significantly associated with variation in practice.


CONCLUSIONS
Factors related to patient characteristics, such as pain severity and co-morbidity, did not seem to explain variation in treatment modalities for patients with knee OA. Variation was associated with the following factors: physiotherapists having Internet access at work, physiotherapists having searched databases for the last six months and the gender of the therapist. There is a need for more studies of determinants for physiotherapy practice.