Replantation of amputated fingertips: reconstruction of circulation via proximal subungual arch artery or nail bed vein anastomosis.

Background: If no palmar digital artery or subcutaneous vein is available for anastomosis in the amputated distal fingertip tissue, conventional replantation methods cannot effectively restore blood circulation. This study introduces a surgical approach and evaluates its outcomes for replantation of distal fingertip amputated tissue when the palmar digital artery is unavailable for anastomosis. In such cases, the proximal subungual arch artery is anastomosed as an alternative to the palmar digital artery to restore arterial supply, while standard anastomosis of the dorsal subcutaneous vein is performed to restore venous drainage. When the subcutaneous vein is unavailable, the proximal nail bed vein is anastomosed as an alternative to the subcutaneous vein to restore venous drainage, while standard anastomosis of the palmar digital artery is performed to restore arterial supply. The aim is to improve the replantation rate, survival rate, and survival quality of amputated distal fingertip tissue. Methods: From January 2019 to December 2025, our institution performed replantation surgery on three patients with three digits of distal fingertip amputated tissue lacking a palmar digital artery for anastomosis. In these cases, the proximal subungual arch artery was anastomosed as an alternative to the palmar digital artery to restore arterial supply, while standard anastomosis of the dorsal subcutaneous vein was performed to restore venous drainage. Additionally, replantation surgery was performed on nine patients with nine digits of distal fingertip amputated tissue lacking a subcutaneous vein for anastomosis. In these cases, the proximal nail bed vein was anastomosed as an alternative to the subcutaneous vein to restore venous drainage, while standard anastomosis of the palmar digital artery was performed to restore arterial supply. Intraoperative measurements included the diameter of the proximal subungual arch artery or proximal nail bed vein used as an alternative vessel, and the duration of finger ischemia as well as the operative time were recorded. Postoperatively, the survival of the replanted tissue was observed, and complications such as vascular crisis, wound infection, nonunion of the fracture, and tissue necrosis were assessed. At the final follow-up, the function of the affected finger was evaluated using the Fingertip Injuries Outcome Score (FIOS). Results: In the 3 patients (3 digits) who underwent anastomosis of the proximal subungual arch artery as an alternative to the palmar digital artery, the arterial diameters were 0.2 mm, 0.3 mm, and 0.3 mm (mean: 0.27 mm). In the 9 patients (9 digits) who underwent anastomosis of the proximal nail bed vein as an alternative to the subcutaneous vein, the venous diameters ranged from 0.6 mm to 1.0 mm (mean: 0.72 mm). The mean warm ischemia time for the 12 amputated digits was 4.75 h (range: 3-11 h). The mean operative time for the 12 replantations was 1.97 h (range: 0.5-2.83 h). All 12 replanted digits survived, with no cases of vascular crisis, wound infection, fracture nonunion, or tissue necrosis. At a mean follow-up of 12.17 months (range: 3-43 months).The function scores of the affected fingers ranged from 11 to 15, with an average of 12.5. The results were rated as excellent in 6 cases and good in 6 cases. Conclusions: The proximal subungual arch artery and nail bed vein can be anastomosed under microscopic visualization. Anastomosis of the proximal subungual arch artery can replace the palmar digital artery to restore arterial supply to the distal amputated tissue block, while anastomosis of the proximal nail bed vein can replace the subcutaneous vein to restore venous drainage of the distal amputated tissue block. For patients with distal fingertip amputation injuries lacking a palmar digital artery or subcutaneous vein available for anastomosis, replantation can be performed by intraoperatively anastomosing the proximal subungual arch artery as an alternative to the palmar digital artery or the proximal nail bed vein as an alternative to the subcutaneous vein to restore arterial supply or venous drainage. This approach effectively improves the replantation rate, survival rate, and survival quality of the replanted tissue, and is worthy of widespread clinical application.