OBJECTIVE: The purpose of this study were to present a new surgical classification, based on types of injuries, and to evaluate significance of our post-operative protocol for fingertip replantation, especially crush-avulsion cases.

METHODS:Twenty fingertip amputations in 20 consecutive patients were replanted at our institute for recent 5 years. There were 17 male patients and 3 female patients, ranging in age from 19 to 62 years(mean,45.3years). All cases were classified as crush and avulsion according to Yamano. There were 13 amputations in Zone I and 7 in Zone II according to Tamai’s classification for the level of amputation. Also, we classified our cases based on the type of injury. [New Classification] Type IA: Distal transverse palm arterial arch (DTPA) is remained in the proximal part Type IB: DTPA is remained in the amputated part Type II : Loss of DTPA There were 4 cases in Type IA, 4 in Type IB, and 12 in Type II. Postoperatively, 12000–24000U of urokinase and 500 ml of low molecular-weight dextran were given intravenously for 7 consecutive days. In very severe crush/avulsion cases, 10000–15000 U of heparin were given intravenously for 5 days additionally.

RESULTS: The overall survival rate of the 20 replantations was 90.0% (zone I:83.3%, Zone II:100%). The survival rate was 100% in type IA, 100% in type IB, and 83.3% in type II. For arterial repair, vein grafts were necessary in 1 of 4 type IA(25%), 1 of 4 type IB(25%), and 11 of 12 type II(91.7%). In 3 of 4 type IA, end to end anastomosis were possible by the technique of transpositioning DTPA. In 3 of 4 type IB, proper digital artery was anastomosed to central artery of the pulp. Regarding functional outcomes with a follow-up period greater than 6mons, excellent cases were 87.0% (according to Tamai’s functional classification). The mean range of motion of the distal interphalangeal joint was 40 degrees. All patients achieved protective sensation of replanted fingertips. Other complications were cold intolerance(22.2%), nail deformity(66.6%), and pulp atrophy (33.3%). Blood transfusions were not necessary in all cases.

CONCLUSIONS: Our new classification of fingertip amputation based on DTPA was available for strategy of arterial repair, because if DTPA is lost, most cases (91.7%) need vein grafts. Also, in crush/avulsion fingertip amputation, our clinical protocol was very useful and raised success rate of fingertip replantation (90.0%) for crush-avulsion cases.

This study was undertaken to elucidate the mechanism of biological repair at the tendon-bone junction in a rat model. The stump of the toe flexor tendon was sutured to a drilled hole in the tibia (tendon suture group, n = 23) to investigate healing of the tendon-bone junction both radiologically and histologically. Radiological and histological findings were compared with those observed in a sham control group where the bone alone was drilled (n = 19). The biomechanical strength of the repaired junction was confirmed by pull-out testing six weeks after surgery in four rats in the tendon suture group. Callus formation was observed at the site of repair in the tendon suture group, whereas in the sham group callus formation was minimal. During the pull-out test, the repaired tendon-bone junction did not fail because the musculotendinous junction always disrupted first.

In order to understand the factors that influenced callus formation at the site of repair, four further groups were evaluated. The nature of the sutured tendon itself was investigated by analysing healing of a tendon stump after necrosis had been induced with liquid nitrogen in 16 cases. A proximal suture group (n = 16) and a partial tenotomy group (n = 16) were prepared to investigate the effects of biomechanical loading on the site of repair. Finally, a group where the periosteum had been excised at the site of repair (n = 16) was examined to study the role of the periosteum. These four groups showed less callus formation radiologically and histologically than did the tendon suture group.

In conclusion, the sutured tendon-bone junction healed and achieved mechanical strength at six weeks after suturing, showing good local callus formation. The viability of the tendon stump, mechanical loading and intact periosteum were all found to be important factors for better callus formation at a repaired tendon-bone junction.

Fracture of the atlas is rare in children. We report a case of fracture of the atlas through a synchondrosis of the anterior arch complicated by atlantoaxial rotatory fixation in a four-year-old girl.