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

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.