Leech therapy for chronic non-specific low back pain: a randomized controlled trial
Hohmann CD, Stange R, Steckhan N, Robens S, Ostermann T, Paetow A, Michalsen A (2018) · Deutsches Ärzteblatt International · n=56
RCT evidence detailTrial reference
GRADE LowCohort / case series
Study Profile
- Design
- single-center, open-label, randomized controlled trial (Berlin)
- Sample size (n)
- 56
- Intervention
- Single session of 4-7 Hirudo medicinalis leeches applied to paraspinal muscles at the level of maximal pain
- Comparator
- Standardized exercise program (3x/week for 4 weeks) plus pain education
- Primary endpoint
- Pain intensity (mean of last 7 days on 0-10 NRS) at day 28
- Primary result
- Pain NRS dropped from 5.6 to 3.2 in leech group vs 5.4 to 4.6 in exercise group at day 28 (between-group difference 1.4 points, 95% CI 0.7-2.1, p<0.001)
- Effect size (Cohen's d)
- 0.74
- Follow-up duration
- 4 months
- PMID
- 30636672
Key Findings
- First RCT of hirudotherapy for chronic non-specific low back pain
- Effect emerged at day 7 and sustained through 4 months
- Oswestry Disability Index improved 8.4 points in leech vs 2.7 in exercise (p=0.004)
- Patient global impression of change favored leech arm (74% 'much improved' vs 32%)
- Mild local AEs only — no neurological events from paraspinal application
Limitations
- Single center (Charité Berlin)
- Open-label, no sham
- Comparator exercise program may not represent best-practice multimodal LBP care
- Sample (n=56) modest
- Excluded patients with radiculopathy — generalizability narrow
Clinical Implications
Hohmann 2018 extends hirudotherapy efficacy from joint OA to chronic musculoskeletal pain syndromes. Chronic non-specific LBP is the most common indication in primary care and notoriously hard to treat. Demonstrating a 7-day onset of pain relief with a single application offers a novel option, particularly for patients seeking non-pharmacologic care. The trial supports cautious clinical use at the GRADE 'low' tier pending replication and longer follow-up.