Digital avulsion injuries: epidemiology and factors influencing finger preservation.

Introduction: The surgical treatment of ring avulsion injuries is still challenging. This study provides data concerning epidemiology and factors influencing finger survival rate. We wanted to answer the question whether microsurgical advancement and a high level of surgical expertise nowadays may improve the outcome.

Patients And Methods: Between 11/2007 and 06/2016 95 ring avulsions were treated (classified according to Kay). Complete documentation was available from 87 patients (25 female). The mean age was 34 (4-82) years. Intact perfusion (Kay I) was preoperatively seen in 20 fingers while 67 were avascular (Kay II-IV).

Results: In 89%, the ring finger was injured during mainly private accidents. Primary amputation was performed in 38 Kay II-IV injuries. Revascularization was applied to 29 fingers while 8 of them (28%) primarily failed. After initially successful revascularization/replantation of 21 fingers, 6 had to be amputated secondarily (success rate: 52%). There was no significant correlation between affected finger and rate of finger preservation. Climbing over a fence as trauma mechanism significantly correlated with lower finger preservation rates and higher incidence of Kay IV injuries.

Conclusion: Despite microsurgical advances and high levels of surgical expertise the finger survival rate after ring avulsion injuries still seems to be mostly influenced by the extend of intrinsic damage.