The efficacy and safety of medical leech therapy for osteoarthritis of the knee: A meta-analysis of randomized controlled trials
Meta-analysis published in International journal of surgery (London, England) (2018)
Abstract
BACKGROUND: It is controversial on whether medical leech therapy is effective in improving pain and functional outcome in patients with knee osteoarthritis (OA). Therefore, we perform a meta-analysis from randomized controlled trials (RCTs) to evaluate the efficacy and safety of medical leech therapy in patients with knee OA. MATERIALS AND METHODS: The PubMed, EMBASE, ScienceDirect, and Cochrane Library databases were systematically searched for literature up to January 2018. RCTs involving medical leech therapy in patients with knee OA were included. Two independent reviewers performed independent data abstraction. The I2 statistic was used to assess heterogeneity. A fixed or random effects model was adopted for meta-analysis. All meta-analyses were performed by using STATA 12.0. RESULTS: Four RCTs with 264 patients were included in this meta-analysis. The current meta-analysis showed that there were significant differences in terms of visual analogue scale (VAS) scores and WOMAC scores at 1 week, 4weeks and 7 weeks compared with control groups. However, leech therapy was associated with a significantly higher incidence of adverse events. The overall evidence quality is moderate, which means that further research is likely to significantly change confidence in the effect estimate but may change the estimate. CONCLUSION: Medical leech therapy was associated with a significantly improved outcome in pain relief and functional recovery in patients with symptomatic knee OA. However, given the inherent limitations in the included studies, this conclusion should be interpreted cautiously.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
It is controversial on whether medical leech therapy is effective in improving pain and functional outcome in patients with knee osteoarthritis (OA). Therefore, we perform a meta-analysis from randomized controlled trials (RCTs) to evaluate the efficacy and safety of medical leech therapy in patients with knee OA.
Why This Matters for Hirudotherapy
This meta-analysis synthesized four randomized controlled trials (264 patients total) evaluating medical leech therapy for symptomatic knee osteoarthritis, reporting significant improvements in VAS pain scores and WOMAC scores at 1, 4, and 7 weeks compared with controls, alongside a significantly higher incidence of adverse events. This study is directly relevant to hirudotherapy, as it provides aggregated clinical evidence on the efficacy and safety of medicinal leech application for a common musculoskeletal condition, addressing ongoing controversy about its therapeutic value. The authors rated the overall evidence quality as moderate and cautioned that inherent limitations in the included studies warrant careful interpretation. While the findings support pain relief and functional recovery, the elevated adverse event rate and limited number of trials mean that conclusions remain provisional and further high-quality RCTs could alter the effect estimates.
Citation
The efficacy and safety of medical leech therapy for osteoarthritis of the knee: A meta-analysis of randomized controlled trials.
Wang H, Zhang J, Chen L · International journal of surgery (London, England), 2018
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