Effectiveness of leech therapy in chronic lateral epicondylitis: a randomized controlled trial
Bäcker M, Lüdtke R, Afra D, Cesur Ö, Langhorst J, Fink M, Bachmann J, Dobos GJ, Michalsen A (2011) · The Clinical Journal of Pain · n=40
Study Profile
- Design
- single-center, open-label, randomized controlled trial (Kliniken Essen-Mitte)
- Sample size (n)
- 40
- Intervention
- Single treatment with 2-4 locally applied Hirudo medicinalis leeches over the lateral epicondyle
- Comparator
- 30-day course of topical diclofenac applied to the lateral epicondyle
- Primary endpoint
- Change of pain sum score on day 7, calculated from 3 VAS scales for pain during motion, grip, and rest
- Primary result
- Pain sum score decreased from 143.7 ± 36.9 to 95.3 ± 45.1 in leech group vs 131.6 ± 29.6 to 134.7 ± 70.7 in diclofenac group at day 7 (mean difference -49.0, 95% CI -82.9 to -15.1, p=0.0075); group difference reduced by day 45 (-27.5, p=0.110) as diclofenac effect emerged
- Follow-up duration
- 45 days
- PMID
- 21368667
Key Findings
- First RCT of leech therapy for chronic lateral epicondylitis (tennis elbow)
- Significant short-term (7-day) pain reduction vs topical diclofenac
- DASH disability score improved more strongly in leech arm, with effect most prominent at day 45 (p=0.0007)
- Quality-of-life (SF-36) increased non-significantly in leech group; grip strength favored leech
- Results not affected by outcome expectation — argues against pure placebo explanation
Limitations
- Single center (Kliniken Essen-Mitte) — same group as Michalsen 2003 and Michalsen 2008
- Open-label, no sham control
- Small sample (n=40)
- Topical diclofenac comparator may underestimate maximum NSAID effect (oral or injection routes not tested)
- 45-day follow-up too short for a chronic-relapsing condition
Clinical Implications
Bäcker 2011 extended hirudotherapy's evidence base from OA into tendinopathy and is the first RCT of leech therapy for lateral epicondylitis indexed in PubMed. The 7-day onset of pain relief in a notoriously refractory condition supports cautious clinical use, particularly for NSAID-intolerant or corticosteroid-averse patients. The trial is referenced in subsequent narrative reviews of leech therapy for pain syndromes (Koeppen 2013 Wien Med Wochenschr) and supports the ASH clinical indication for lateral epicondylitis at the GRADE 'low' tier pending independent replication outside Essen.