Radical resection of a giant cell tumor of the distal ulna and reconstruction with a 3D-printed distal ulnar prosthesis: A case report.

Rationale: Giant cell tumors (GCTs) of the distal ulna are rare. Despite their benign nature, these tumors can exhibit local aggressiveness and have the potential to recur after undergoing conventional treatment involving curettage and bone grafting. For aggressive GCTs, radical resection is more suitable. However, these methods have inherent shortcomings, including a high postoperative recurrence rate and poor mechanical stability. Medical applications of the 3D printing technique are on the rise, with orthopedic repair and reconstruction benefiting from the successful implementation of custom-made prostheses created via 3D printing technology.

Patient Concerns: A 38-year-old male patient presented to a local clinic complaining of a slow-growing painless on over the ulnar aspect of his left wrist for 1 month. The biopsy confirmed the diagnosis of GCTs and was graded as Campanacci grade III.

Diagnoses: The diagnosis of GCTs of the distal ulnar was confirmed by biopsy.

Interventions: The patient received a 2-month preoperative adjuvant chemotherapy with denosumab. Then, a radical distal ulnar resection and hemiarthroplasty are performed using a 3D-printed prosthesis to reconstruct wrist joint function.

Outcomes: During the 2-year follow-up after the surgery, there were no signs of recurrence, and the left wrist function of the patient remained normal.

Lessons: A well-fitted personalized prosthesis, made using 3D printing techniques, can effectively reconstruct joint function and bone defects resulting from radical distal ulnar resection due to GCTs. This case demonstrates that the combination of radical resection of a GCT in the distal ulna and reconstruction with a 3D printed personalized prosthesis could lead to successful oncologic and functional outcomes.