Reverse shoulder arthroplasty in cases of glenoid defects using primary-revision metaglene

BACKGROUND: Reverse shoulder arthroplasty is one of the surgical treatment methods of the shoulder joint injuries and diseases accompanied by pronounced changes in the anatomy of the articular structures. Considering the positive aspects of reverse shoulder arthroplasty, the indications for this operation are expanding over time. However, during this operation, errors are possible that lead to early dislocation of the endoprosthesis, compression of the metaglene to the scapula, screw instability and migration of the scapular component. Given the lack of a generally recognized clear algorithm of actions in these complex cases, the problem of reversible shoulder arthroplasty in case of defects in the articular surface of the scapula are relevant. AIM: To develop and evaluate the effectiveness of the method of compensating for the lack of bone tissue of the scapula in the reverse shoulder arthroplasty MATERIALS AND METHODS: In the Department of Adult Orthopaedics of the N.N. Priorov National Research Medical Center, reverse shoulder arthroplasty was performed in patients with scapular bone mass deficiency, who needed to fill in both marginal defects for the installation of metaglene with the correct angle of inclination, and the replacement of extensive defects with the necessary level of glenosphere lateralization. RESULTS: Follow-up of patients who underwent glenoid remodeling using bone autoplasty and subsequent shoulder reverse artroplasty within a period of 6 to 24 months. Remodeling and osseointegration of the grafts were determined, without signs of metaglene instability by the end of the 3rd month after the operation. The complex of rehabilitation measures and the time of recovery of movements in the operated joint did not differ from those of conventional reverse arthroplasty. CONCLUSION: Given the high efficiency of the proposed algorithm, the method used to compensate for the lack of bone tissue of the scapula in shoulder reverse arthroplasty can be recommended for implementation in a wide clinical practice.

Maximizing Muscle Function in Cuff-Deficient Shoulders: A Rehabilitation Proposal for Reverse Arthroplasty

Purpose The purpose of this review is to describe the role of altered joint biomechanics in reverse shoulder arthroplasty and to propose a rehabilitation protocol for a cuff-deficient glenohumeral joint based on the current evidence. Methods and Materials: The proposed rehabilitation incorporates the principles of pertinent muscle loading while considering risk factors and surgical complications. Results In light of altered function of shoulder muscles in reverse arthroplasty, scapular plane abduction should be more often utilized as it better activates deltoid, teres minor, upper trapezius, and serratus anterior. Given the absence of supraspinatus and infraspinatus and reduction of external rotation moment arm of the deltoid in reverse arthroplasty, significant recovery of external rotation may not occur, although an intact teres minor may assist external rotation in the elevated position. Conclusion Improving the efficiency of deltoid function before and after reverse shoulder arthroplasty is a key factor in the rehabilitation of the cuff deficient shoulders. Performing exercises in scapular plane and higher abduction angles activates deltoid and other important muscles more efficiently and optimizes surgical outcomes.