Glenohumeral arthrodesis is a salvage procedure in the shoulder with few indications. However, in young patients with flail shoulder, shoulder arthrodesis is a durable, functional option. Allograft or autograft can be used to reconstruct the defect during glenohumeral arthrodesis. Autografts be vascularized or nonvascularized. The use of vascularized autograft can increase operative time and is associated with substantial donor-site morbidity. The reamer-irrigator-aspirator, a system that irrigates and aspirates reamed bone and medullary contents, including mesenchymal stem cells, isolating bone graft with little donor-site morbidity, is a potential solution. We used this system for glenohumeral arthrodesis in a 22-year-old man with massive proximal humeral bone loss, axillary nerve injury, deltoid muscle atrophy, and soft-tissue coverage needs complicated by infection. Isolated graft was placed in the bony defect, and the arthrodesis was stabilized with a 16-hole plate. There were no intraoperative or postoperative complications. At 3 months after surgery, his bone graft had incorporated, with no evidence of instrumentation loosening or breakage. Six months after surgery, he had good function of the operative extremity with consolidation of the fusion mass and no loss of fixation. This patient's outcome highlights that this method has low donor-site morbidity, allows for rapid osseointegration and union, and preserves functional outcomes, despite necessary humeral shortening.