Comparison of the effectiveness of medicinal leech and TENS therapy in the treatment of primary osteoarthritis of the knee: A randomized controlled trial; [Vergleich der Wirksamkeit von medizinischer Blutegel- und TENS-Therapie zur Behandlung der primären Gonarthrose: Eine randomisierte kontrollierte Studie]

Objectives: The aim of this study was to evaluate the effects of leech therapy in the treatment of knee osteoarthritis in terms of duration of effectiveness and symptom relief and to compare these results with transcutaneous electrical nerve stimulation (TENS) therapy. Material and methods: This study was designed as a prospective, single center, randomized, single-blind and parallel group study. A total of 90 patients were included in the study, 46 in the leech group and 44 in the TENS group. Primary outcome measures were changes of the pain scores in visual analogue scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) on the measurements day 0, 21 and 180. Secondary outcome measures were the changes in the sub-groups of the WOMAC scores. Five leeches were applied to the affected knee, once every week for 3 weeks. Results: The VAS pain score showed a similar decrease in both groups in the evaluation on day 21 (p < 0.001). The course of the change of the VAS pain score in both groups was similar in the comparisons between groups. Long-term benefits of the TENS therapy group were slightly more than the leech therapy group. All the sub-scores of WOMAC in both therapy groups showed a similar decrease (p = 0.819). Throughout the study this decrease was statistically significant in both groups (p < 0.001). Conclusion: Leech therapy relieves symptoms in patients with osteoarthritis of the knee and is as effective as TENS therapy in the management of osteoarthritis of the knee. This treatment has the potential of being an additional or alternative therapy for the non-surgical management of osteoarthritis of the knee. © 2016, Springer-Verlag Berlin Heidelberg.