Major Upper Extremity Amputation: Injury Patterns and Outcomes Associated With Replantation

Background:  Limited evidence exists to guide surgical decision-making following traumatic major upper extremity amputations, with few published reports focusing on clinical indications for attempting replantation.^1-4  This study characterizes major upper extremity amputation in a civilian population, ascertains clinical factors associated with the decision to attempt replantation, and analyzes associations between reconstructive efforts and favorable clinical outcomes.

Methods:  A retrospective cohort study was conducted on patients treated at the University of Michigan Level One trauma center between June 2000 and August 2011.  Patients who experienced traumatic upper extremity amputation at or proximal to the radio-carpal joint were included in the study.  The subset of patients who subsequently underwent replantation was identified.  Medical records were reviewed to collect patient demographics, injury characteristics, operative details, and clinical outcomes.  Bivariate analysis was performed to identify factors associated with attempted replantation, as well as resultant clinical outcomes.

Results:  Sixty two patients were treated for traumatic upper extremity amputation and 20 patients underwent attempted replantation.  Mean follow up was 2.8 years. Injury factors associated with attempted replantation included a sharp/penetrating injury (p=0.004), distal level of amputation (p=0.017), injury severity score (ISS) of less than 16 at presentation (p=0.020), absence of avulsion (p=0.002), absence of significant contamination (p=<0.001), and lack of multilevel involvement (p=0.007).  Upper extremity replantation exhibited a complete survival rate of 70%.  An ISS ≥ 16 was associated with failure of the replanted limb (p=0.004).  Patients who underwent replantation demonstrated an increased overall rate of secondary surgical revisions (75%) compared with those who were not replanted (26.2%, p=<0.001), including a significantly increased requirement for post-operative split-thickness skin grafts (30% vs. 2.4%, p=0.003) and complex tissue rearrangements (20% vs. 0%, p=0.009).  Replanted patients also demonstrated an increased overall rate of postoperative complications (85.0%) compared to patients who received revision amputations (52.4%, p=0.023), and specifically exhibited an increased rate of wound breakdown/chronic wound formation (40% vs. 14.3%, p=0.048).  Replantation was also associated with a greater length of hospital stay (15 vs. 9 days, p=0.024).

Conclusion:  Several injury characteristics are associated with the decision to attempt replantation of the upper extremity.  When performed, a high global injury severity (ISS≥16) is associated with replantation failure.  Furthermore, patients who undergo attempted replantation demonstrate higher resource utilization, a finding which spurs further cost-analysis and outcomes investigation.