The Effectiveness of Leech Therapy in Chronic Low Back Pain A Randomized Controlled Trial

Background: Leech therapy has been found to be effective in the treatment of a number of chronic musculoskeletal pain syndromes. Leeches are also often used empirically to treat chronic low back pain, but data from clinical trials have been lacking to date. We therefore conducted the first randomized trial of leech therapy for chronic low back pain. Methods: Patients with chronic low back pain were randomized to receive either a single session of local treatment with 4-7 leeches or four weekly sessions of exercise therapy (1 hour each) led by a physical therapist. The primary endpoint was a change in average back pain intensity, as measured using a 100-mm visual analog scale (VAS), after 28 days. Secondary end-points included functional impairment (Roland-Morris Disability Questionnaire, Hannover Functional Ability Questionnaire), quality of life (Short-Form Health Questionnaire [SF 36]), pain perception (pain perception scale = Schmerzempfindungsskala [SES]), depressivity (Center for Epidemiological Studies Depression Scale [CES-D]), and analgesic consumption (questionnaire/diary). Trial visits took place before treatment and on days 28 +/- 3 and 56 +/- 5 after the start of treatment; the overall duration of the trial was 56 +/- 5 days. Results: The mean low back pain score improved from 61.2 +/- 15.6 before treatment to 33.1 +/- 22.4 on day 28 in the leech therapy group (n = 25) and from 61.6 +/- 14.8 to 59.8 +/- 16.7 in the exercise therapy group (n = 19) (group difference -25.2; 95% confidence interval [-41.0; -9.45]; p = 0.0018). Significant benefits of leech therapy were also found at both time points with respect to physical impairment and function as well as physical quality of life. The patients' expectations from treatment were higher in the leech therapy group but did not significantly affect the findings. Conclusion: A single session of leech therapy is more effective over the short term in lowering the intensity of pain over the short term and in improving physical function and quality of life over the intermediate term (4 weeks and 8 weeks, respectively). The limitations of this trial are the lack of blinding and the small number of patients. Leech therapy appears to be an effective treatment for chronic low back pain.