The application of custom 3D-printed hemi-elbow prosthesis in the repair and reconstruction of bone defects following distal humeral tumor resection.

Abstract

<h4>Background</h4>Reconstruction of bone defects after distal humeral tumor resection remains technically challenging because of the complex anatomy of the elbow and the need to preserve postoperative joint function. This study aimed to investigate the clinical value of a custom 3D-printed hemi-elbow prosthesis for the repair and reconstruction of distal humeral bone defects after tumor resection and to evaluate the short-term and midterm outcomes of patients treated with this technique.<h4>Methods</h4>This retrospective study included 5 patients with aggressive or malignant tumors of the distal humerus who were treated at our center between September 2021 and August 2023. All patients underwent tumor resection followed by reconstruction with a custom 3D-printed hemi-elbow prosthesis.<h4>Results</h4>The surgical procedures for all 5 patients were completed successfully. All cases achieved either marginal or wide resection, and the prostheses were successfully implanted in each case without any intraoperative complications. The mean follow-up period was 33.4 ± 10.8 months (range: 24-46 months). Four patients remained alive without evidence of tumor recurrence, while 1 patient ultimately died due to lung metastasis progression. At the final follow-up, there were no signs of degenerative joint disease, aseptic loosening, or postoperative prosthetic infections. However, complications included 1 case of early ulnar nerve palsy that subsequently developed elbow stiffness and 1 case of ulnar nerve injury.At final follow-up, the mean elbow flexion was 126° ± 15° (range, 100°-140°), the mean extension deficit was 15° ± 9° (range, 5°-30°), and the mean arc of elbow motion was 111° ± 22° (range, 70°-135°). The mean forearm rotation was 161° ± 16° (range, 130°-175°). The average Musculoskeletal Tumor Society 93 score was 27.2 points, and the average Mayo Elbow Performance score was 97 points.<h4>Conclusion</h4>The application of a custom 3D-printed hemi-elbow prosthesis for the repair and reconstruction of bone defects following distal humeral tumor resection results in good elbow joint mobility and postoperative function. Subsequent follow-up showed no occurrence of degenerative joint disease, loosening, or infection-related complications. Additionally, the use of mesh grafts facilitates improved joint capsule reconstruction and promotes early postoperative mobilization. To reduce the risk of postoperative elbow stiffness, careful attention must be paid to the placement of mesh grafts, minimizing their contact with muscle bellies to lower the risk of adhesions. Further improvements in prosthetic design and an emphasis on postoperative elbow rehabilitation are necessary to enhance clinical outcomes.