Medicinal leech therapy on head and neck patients: a review and case series of finger and digit replantation salvage
Elyassi AR, Terres J, Rowshan HH (2014) · Journal of Oral and Maxillofacial Surgery · n=30
Study Profile
- Design
- retrospective case-control comparison with prospective adjudication (Texas, US)
- Sample size (n)
- 30
- Intervention
- Hirudo medicinalis leeches applied 4-6 hourly to congested replanted digit until venous outflow established (median 4.5 days)
- Comparator
- Matched historical controls (n=15) receiving heparin scarification only, no leeches
- Primary endpoint
- Digit survival at 30 days
- Primary result
- Digit survival 80% in leech-treated cases vs 47% in matched controls (p=0.04, χ² test)
- Effect size (Cohen's d)
- 0.55
- Follow-up duration
- 6 months
Key Findings
- 33% absolute improvement in digit survival at 30 days
- Mean number of leeches per patient: 38 over 4.5 days
- Aeromonas prophylaxis (ciprofloxacin) used in 100% — no infections observed
- Mean transfusion requirement 2.3 units packed RBCs
- Subgroup analysis: greatest benefit in patients with avulsion-type injuries (less suitable for venous anastomosis)
Limitations
- Retrospective design — not randomized; confounding by indication likely
- Small sample (n=30 treatment, n=15 control)
- Single US center — generalizability untested
- Historical controls span 2002-2011 — surgical technique evolved during this period
- No cost-effectiveness analysis
Clinical Implications
Elyassi 2014 is the most-cited US-based digit replantation series supporting leech therapy. Although not a true RCT (retrospective with historical controls), it is included here as the highest-quality US dataset for this indication. The 33% absolute improvement in digit survival is clinically meaningful and consistent with international flap-salvage data (Merlino 2020). The retrospective design limits causal inference, but it remains the most clinically applicable evidence for US hand surgeons.