American Society of Hirudotherapy

Outcomes of single digit replantation for amputation proximal to the flexor digitorum superficialis insertion: A systematic review with meta-analysis

Research article published in Microsurgery (2022)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Meta-analysisDrug DevelopmentWong S et al. · Microsurgery, 2022

Abstract

BACKGROUND: A single digit amputated proximal to the flexor digitorum superficialis (FDS) insertion is a relative contraindication to replantation. The aim of this study is to conduct a systematic review on replantation of these injuries to synthesize best available evidence on outcomes. METHODS: This review was registered in PROSPERO under registration number CRD42021277305. A MEDLINE, CENTRAL, and EMBASE databases search yielded 1536 studies. Primary clinical studies on single digit replantation and functional outcome with at least 10 cases were included. Data on revision amputation and replantation distal to the FDS were collected as comparators. Data extracted included demographics, type of digit, level of injury, secondary surgeries, duration of sick leave, survival, function, and patient-reported outcomes. All studies were assessed using the Risk of Bias In Non-randomized Studies of Intervention (ROBINS-I) tool and data synthesis was completed using RevMan and Microsoft Excel. RESULTS: Six studies representing 182 replanted single digits that were amputated proximal to the FDS insertion were included. The average PIPJ motion of replanted single digits was 50° in those amputated proximal to the FDS insertion compared to 82.5 in those amputated distal to the FDS. The average Michigan Hand Questionnaire (MHQ) score was 84.78 in replantation group versus 76.81 in the amputation group which was statistically significant (p < .00001). Mean Disability of Arm, Shoulder, and Hand Questionnaire (DASH) score was 12 in replantation group compared to 18.5 in amputation group, however this was not statistically significant (p = .17). CONCLUSION: Few studies exist on outcomes of single digit replantations proximal to FDS insertion. Although range of motion is inferior in the replant group, this has increased since initial studies were performed, and patient satisfaction and patient reported outcomes are high. This is promising evidence for achieving reasonable outcomes in replantation of single digits amputated proximal to the FDS. LEVEL OF EVIDENCE: Level III.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeMeta-AnalysisSystematic ReviewJournal Article
Indexed MeSH termsHumansAmputation, TraumaticFinger InjuriesReplantationHandAmputation, SurgicalRetrospective Studies

Summary

Peer-reviewed research on therapeutic compound development relevant to leech-derived anticoagulants and antithrombotic agents. Indexed in PubMed and verified against the NCBI record.

Why This Matters for Hirudotherapy

This PROSPERO-registered systematic review with meta-analysis synthesized 6 studies covering 182 single digits replanted after amputation proximal to the flexor digitorum superficialis (FDS) insertion — a relative contraindication to replantation — and found inferior range of motion (mean PIPJ motion 50° vs 82.5° for distal amputations) but high patient-reported outcomes, including a significantly better Michigan Hand Questionnaire score in the replantation versus revision-amputation group (84.78 vs 76.81, p < .00001). The relevance to hirudotherapy is the setting rather than the intervention: these proximal single-digit replants are precisely the marginal, venous-congestion-prone cases in which medicinal leeches are most often called upon to salvage outflow, so evidence that such replants yield acceptable patient-reported outcomes supports continued attempts where leech adjuncts may matter. As a review the authors flag the very small evidence base (6 studies, Level III, ROBINS-I-assessed non-randomized data) and the abstract does not address leech use directly.

Citation

Outcomes of single digit replantation for amputation proximal to the flexor digitorum superficialis insertion: A systematic review with meta-analysis.

Wong S et al. · Microsurgery, 2022

Added to ASH library: May 28, 2026 · Site last updated: June 18, 2026

This website provides educational information and does not constitute medical advice, diagnosis, or treatment recommendations. Medicinal leech therapy carries clinically meaningful risks and should be performed only by qualified clinicians under institutionally approved protocols. FDA 510(k) clearance for medicinal leeches is limited to specific indications; investigational and off-label discussions are labeled accordingly. For patient-specific guidance, consult a qualified healthcare provider.