BACKGROUNDAn increasingly aging population implies an increasing prevalence of osteoarthritis (OA) of hip or knee. It has been ascertained that unspecific hydrotherapy of OA according to Sebastian Kneipp not only improves the range of mobility but also reduces pain significantly and increases the quality of life of the patients affected.

OBJECTIVEThe main aim of this pilot study was to determine the effects of hydrotherapy in comparison to conventional physiotherapy, and to analyze the feasibility of the study design under clinical circumstances.

DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONSThe study design is a prospective randomized controlled three-arm clinical pilot trial, carried out at a specialist clinic for integrative medicine. Thirty patients diagnosed with symptomatic OA of hip or knee and radiologic findings were randomly assigned to one of two intervention groups and a control group: hydrotherapy (group 1), physiotherapy (group 2), and both physiotherapy and hydrotherapy (group 3, control group) of the affected joint.

MAIN OUTCOME MEASURES

PRIMARY OUTCOMEpain intensity of the affected joint in the course of inpatient treatment; secondary outcome: health-related quality of life, joint-specific pain and mobility in the course of the study.

RESULTSConcerning the main outcome, intervention group 1 showed most beneficial effects in the course of inpatient treatment, followed by groups 3 and 2, and also the indirect flexion ability of hip or knee together with the general patient mobility through the "timed up and go" test were mainly improved within group 1 followed by groups 3 and 2.

CONCLUSIONThe results of this pilot study demonstrate beneficial effects of hydrotherapy. The study design is feasible. For statistically significant evidence and a robust conclusion of efficacy of Kneipp's hydrotherapy, a larger sample size is necessary.

TRIAL REGISTRATION NUMBERNCT 00950326.