Arthrodesis of the shoulder.

Shoulder arthrodesis is an end-stage salvage option for the failing, painful joint that cannot undergo or has failed reconstruction. It is indicated for irreversible and nonreconstructible massive rotator cuff tears and deltoid muscle denervation as well as for detachment of the deltoid from its origin. Rarely, arthrodesis is done to stabilize the glenohumeral joint after many failed attempts at shoulder reconstruction. Arthrodesis for failed prosthetic arthroplasty or tumor resection presents additional challenges because of the associated bone loss on the humeral and/or glenoid side of the joint. Primary arthrodesis requires rigid internal plate fixation and both an extra- and an intra-articular site of fusion. Depending on bone volume and quality needed, the patient may require bracing for 8 to 10 weeks, autogenous or allograft bone grafting, or a vascularized fibular bone graft to reconstruct the bone deficiency, along with prolonged spica cast immobilization. The optimal position for arthrodesis is 20 degrees of forward flexion, 20 degrees of abduction, and 40 degrees of internal rotation, with modifications based on patient body size or other patient-specific factors. Bone fusion is attained in nearly all patients, with marked pain reduction and improved function. Postoperatively, the patient should be able to lift the arm to near shoulder height and to reach the top of the head, the mouth, the ipsilateral back pocket, and the groin. Complications include nonunion, malposition, pain associated with prominent hardware, and periarticular fractures.