Effectiveness of leech therapy in osteoarthritis of the knee: a randomized, controlled trial
Randomized controlled trial published in Annals of Internal Medicine (2003)
Abstract
BACKGROUND: Leech therapy was commonly used in traditional medicine for treating localized pain. Clinically significant pain relief after leech therapy for osteoarthritis of the knee has been demonstrated by preliminary data. OBJECTIVE: To evaluate the effectiveness of leech therapy for symptomatic relief of osteoarthritis of the knee. DESIGN: Randomized, controlled trial. SETTING: Outpatient department for integrative medicine of an academic teaching hospital. PATIENTS: 51 patients with osteoarthritis of the knee (leech therapy: 24 patients, mean age [+/-SD], 62.5 +/- 10.2 years; topical diclofenac therapy: 27 patients, mean age [+/-SD], 65.5 +/- 6.7 years). INTERVENTION: A single treatment with 4 to 6 locally applied leeches (leech therapy group) or a 28-day topical diclofenac regimen (control group). MEASUREMENTS: Mean of the pain, function, and stiffness subscores of the Western Ontario and McMaster Universities Osteoarthritis Index and physical sum score of the Medical Outcomes Study 36-Item Short-Form Health Survey with group comparisons at days 3, 7, 28, and 91. RESULTS: The primary end point, pain at day 7, was reduced from a mean (+/-SD) of 53.5 +/- 13.7 to 19.3 +/- 12.2 after leech therapy compared with 51.5 +/- 16.8 to 42.4 +/- 19.7 with topical diclofenac (estimated group difference, -23.9 [95% CI, -32.8 to -15.1]; P < 0.001). Although the difference between group pain scores was no longer significant after day 7, differences for function, stiffness, and total symptoms remained significant in favor of leech therapy until the end of study and for quality of life until day 28. Results were not affected by outcome expectation. CONCLUSIONS: Leech therapy helps relieve symptoms in patients with osteoarthritis of the knee. The potential of leech therapy for treating osteoarthritis and the pharmacologic properties of leech saliva remain to be clarified.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Landmark single-blind RCT of 51 patients with knee OA; single leech treatment (4–6 leeches) produced greater pain relief at 7 days versus topical diclofenac (mean VAS reduction 53.5 vs 19.2 mm), persisting at 28 and 84 days.
Why This Matters for Hirudotherapy
This randomized, controlled trial compared the effectiveness of a single leech therapy session against a 28-day topical diclofenac regimen in 51 patients with knee osteoarthritis. Leech therapy resulted in significantly greater pain reduction at day 7, with sustained improvements in joint function, stiffness, and overall symptoms lasting until the end of the 91-day study. The study offers valuable clinical data for hirudotherapy by demonstrating the superiority of leech application over a standard NSAID treatment for localized pain and functional recovery. While well-designed, the authors acknowledge that the specific pharmacologic properties of the leech saliva responsible for these clinical benefits remain to be clarified.
Citation
Effectiveness of leech therapy in osteoarthritis of the knee: a randomized, controlled trial.
Michalsen A et al. · Annals of internal medicine, 2003
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