Purpose: This study aimed to develop a scoring system for evaluating the nail appearance after nail fusion plasty of the duplicated thumb, and to investigate the operation indication of the combination procedure and its effect on the postoperative nail appearance.
Methods: The nail fusion plasty technique was carried out in 20 patients with congenital thumb duplication. The patients were followed up to observe the appearance of nail, and the results were assessed by our nail appearance evaluation criteria.
Results: Twenty patients were followed up for 18 to 92 months (48 months on average). According to our criteria, we achieved excellent results in 12 cases, good in 6 cases, fair in 1 case, and poor in 1 case.
Conclusions: The combination procedure is recommended when the size of the thumb is less than 80% of the size of the normal side or the width of the nail is less than 80% of that of the normal side. Satisfactory results can be obtained by careful operation. The newly devised scoring system assesses the nail appearance in a very comprehensive manner.