Background: Removing the nondominant part and reconstructing the dominant part is the most common procedure for thumb duplication. But the results for complex congenital deformities are not satisfied. This study demonstrates our microsurgical reconstruction procedures for complex thumb duplication. Methods: For Wassel types I, II, and IV, a neurovascular pedicle flap was elevated from the deleted thumb and improved the contour of remained thumb. There were multiple procedures included with bone wedge osteotomy, tendon rebalancing, and ligament reconstruction. For Wassel types V and VI, both thumbs were used to achieve better contour. A neurovascular pedicle wrap-around flap or combined flap was harvested. The relative normal bone and joint were kept, while others were removed. With this procedure, a combined thumb was reconstructed. Percutaneous K-wire was always used to fix the bone and joint after ligament reconstruction completed. The wire was removed after 1 month. Splint was used 8 to 12 weeks after surgery. Results: From 2004 to 2013, 35 children with congenital complex thumb duplication were treated. The age of children at the time of operation was between 8 and 37 months old. The mean follow up after surgery was 27 months. All flaps and transferred thumbs were survived. We had no cases of delayed union or bone resorption. The appearance and function were all satisfactory. Conclusion: This microsurgical procedure can provide a satisfactory option for complex congenital thumb duplication.
