An update on reverse total shoulder arthroplasty: current indications, new designs, same old problems

Abstract

Reverse total shoulder arthroplasty (RTSA) was originally developed because of unsatisfactory results with anatomic shoulder arthroplasty options for the majority of degenerative shoulder conditions and fractures. After initial concerns about RTSA longevity, indications were extended to primary osteoarthritis with glenoid deficiency, massive cuff tears in younger patients, fracture, tumour and failed anatomic total shoulder replacement. Traditional RTSA by Grammont has undergone a number of iterations such as glenoid lateralization, reduced neck-shaft angle, modular, stemless components and onlay systems. The incidence of complications such as dislocation, notching and acromial fractures has also evolved. Computer navigation, 3D planning and patient-specific implantation have been in use for several years and mixed-reality guided implantation is currently being trialled. Controversies in RTSA include lateralization, stemless humeral components, subscapularis repair and treatment of acromial fractures. Cite this article: EFORT Open Rev 2021;6:189-201. DOI: 10.1302/2058-5241.6.200085

The Evolution of Reverse Total Shoulder Arthroplasty—From the First Steps to Novel Implant Designs and Surgical Techniques

“…To overcome complications of glenoid baseplate loosening in the early designs of RTSA, the center of rotation was consequently medialized to reduce the mechanical torque at the glenoid component [ 2 , 36 ]. As a result, higher rates of scapular notching were observed [ 36 ]. Reviewing the literature, incidences of scapular notching following RTSA ranged from 4.6% to 96% [ 37 , 38 , 39 , 40 ].…”

“…One of the most common failures following RTSA is the malpositioning of the glenoid component, which is associated with increased humeral instability, leading to inferior outcomes and ultimately to component loosening [ 36 , 83 , 126 ].…”

Diagnosis and Management of Glenohumeral Arthritis in the Active Adult

“…Recently, Kozak et al and Garver et al have reported promising outcomes in younger age groups, especially in the presence of posterior glenoid wear and/or humeral head subluxation, such as a B2 glenoid 86,89 . One study by Ernstbrunner et al showed an average improvement of 40% in the CS scores and no radiographic signs of loosening of the humeral stem or glenoid component at 11.7 years after surgery 90 .…”

Prosthesis Designs and Tuberosity Fixation Techniques in Reverse Total Shoulder Arthroplasty: Influence on Tuberosity Healing in Proximal Humerus Fractures

“…The original prosthesis had a large hemispherical glenoid component with a small cup covering less than half of the glenosphere and an inlay humeral design with an almost horizontal 155 • neckshaft angle. In this design, the adduction angle is limited, resulting in scapular notching from mechanical impingement of the humerus against the inferior scapular neck [43,44]. Another important limitation of this design is its inability to restore active internal and external rotation due to decreased moment arms of the rotator cuff remnants [45].…”