CLINICAL APPLICATION OF 3D PRINTING TECHNOLOGY FOR PREOPERATIVE PLANNING OF THUMB RECONSTRUCTION

ABSTRACT Objective: This study aimed to explore the clinical application of preoperative precise design for 3D printing and thumb reconstruction, which could help manage the patients with thumb defect and achieve better function and appearance. Methods: This was a retrospective study of 20 patients who underwent the surgery of harvesting toe transplant and thumb reconstruction between January 2015 and December 2016. The 3D model of the thumb defect was created and printed. The dimensions of skin and bones from donor site were precisely designed as reference for surgical operation. The surgery was performed according to the model. Results: Perfect repair of defects was achieved with satisfying appearance and function. The reconstructed thumbs all survived (survival rate of 100%). Follow-up was 3-9 months. The maximum dorsiflexion was 8-30° and the maximum flexion was 38-58°. The two-point sensory discrimination was 9-11 mm. In total, 17 patients reposted “Excellent” satisfaction and three “Good”, each for the reconstructed thumb and hand function, respectively. The satisfaction rate was 85%. Conclusion: Preoperative digital design and 3D printing according to the donor and recipient sites allowed a tailored operation. The operation was more precise, the appearance of the reconstructed thumb was good. Level of Evidence II, Retrospective Study.

Sensate Neurovascular Island Flap for Thumb Reconstruction

Thumb pulp defects require adequate reconstruction for satisfactory sensate function and aesthetic appearance. We report a reconstructive case using a sensate neurovascular island flap raised from the ulnar side of the middle finger for a tactile thumb pad defect. The flap was elevated as a modified version of the conventional heterodigital neurovascular island flap in order to restore thumb sensation without the “double-sensibility” phenomenon. The ulnar digital nerve of the flap was sectioned at the middle phalanx level of the donor digit and coaptated to the ulnar and radial digital nerves of the thumb through end-to-side and end-to-end neurorrhaphy. The remaining radial digital nerve of the donor finger was preserved, and the proximal end of the sectioned nerve was coaptated end-to-side to the radial digital nerve to prevent neuroma formation. No postoperative complications including venous congestion were observed. This technique is a relatively simple and reliable option for reconstructing thump pulp defects.