Ring avulsion replantation is a technically challenging procedure with a very low success rate. Because the zone of arterial injury is more extensive than what it appears to be in such avulsion amputations, a technique was developed to debride the avulsed digital artery for a long distance, extending well into the digital pulp, thereby creating healthy arterial ends to be bridged by one or two segments of long venous grafts. Using this technical approach, 7 patients with complete amputations of ring avulsion injury (Urbaniak's class III) were operated. In all amputations the bone was disrupted at the distal interphalangeal level (except in 1 patient) and the soft tissues at the proximal phalanx level, with the proximal interphalangeal joint and the flexor digitorum superficialis tendons being intact. Results indicated that replantation was successful in all patients. However, 2 patients presented with unusually late arterial failure 28 and 30 days after surgery respectively. Although one of these cases was salvaged by reoperation, the other case (followed by conservative management) demonstrated partial distal necrosis. Therefore, the ultimate success rate in this series was 85% in the long term. At follow-up, sensibility was protective in all patients, with an average static two-point discrimination of 7.8 mm (range, 6-14 mm). The total active motion of the replanted digits was 194 deg on average (range, 155-205 deg) without loss of function of the proximal interphalangeal joint except in 2 patients who had late vascular problems. The authors conclude that microsurgical replantation of completely amputated ring avulsion injuries with an intact proximal interphalangeal joint and flexor digitorum superficialis tendon, is a worthwhile procedure that results in good functional and aesthetic results. Furthermore, using an aggressive approach for debridement of the avulsed digital artery, as described in this article, an experienced microsurgeon can replant successfully nearly all cases. However, one should be cautious in the follow-up of such patients, because late arterial failure may be encountered, as was observed in 2 patients in this series. The authors suggest immediate reoperation in such unusual circumstances.

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The authors describe the functional and aesthetic results of microsurgical replantation of 21 fingertip amputations at or distal to the nail base-namely, zone I amputations. There were 15 male and 6 female patients, with an average age of 26 years (age range, 1-41 years). Replantations were performed using the anastomosis of the artery-only technique, with neither vein nor nerve repair. Venous drainage was provided by an external bleeding method with a fish-mouth incision in "distal" zone I amputations for approximately 7 days, and by the use of leeches in more "proximal" zone I amputations for 10 to 12 days. Results indicated that the overall survival rate was 76%, with 16 of 21 digits surviving. Sensory evaluation at an average follow-up of 12 months (range, 6-18 months) revealed an average static two-point discrimination of 6.1 mm (range, 2.0-8.0 mm). Considering the unfavorable results and the donor site morbidity of various fingertip reconstructions, a microsurgical fingertip replantation should always be considered except in extremely distal, clean-cut, pediatric cases, in which case a composite graft is a possibility. The results of this series indicate that an amputated fingertip in zone I can be salvaged successfully by microvascular anastomosis of the artery only, with a nonmicrosurgical method of venous drainage. Furthermore, acceptable sensory recovery can be expected without any nerve coaptation.

The authors describe a case of microvascular ear replantation with repair of the artery only and medicinal leech therapy that survived for 14 days but ultimately failed as a result of the absence of development of venous channels between the replant and the recipient bed. A 35-year-old man presented with complete avulsion of 80% of the right external ear. The auricle was revascularized successfully via transposition of the superficial temporal artery (STA) and end-to-end anastomosis between the STA and an identified arterial branch on the posterior surface of the ear, using the technique of longitudinal wedge resection. No suitable veins could be found, therefore medicinal leech therapy was used for venous drainage as well as for systemic heparinization. Although the replant remained viable, frequency of leeching did not decrease over 2 weeks. On postoperative day 14, despite obvious viability of the replanted ear, leeching was stopped, considering the ongoing blood loss. Unfortunately, the auricle was found to be necrosed totally the following day. In retrospect, the authors think that inadequate debridement of nonvital tissues may have led to the failure of development of venous channels between the replant and the recipient bed, as manifested by the frequent requirement of leeching to relieve venous congestion long after revascularization. They conclude that the importance of thorough debridement cannot be overemphasized in microsurgical ear replantation with no vein anastomosis, as demonstrated in their patient. From the point of view of creation of venous drainage channels, deepithelialization of the posterior ear skin may be beneficial.