Grammont reverse prosthesis: Design, rationale, and biomechanics

222

129

Background Reverse total shoulder arthroplasty (RTSA) was introduced to treat rotator cuff tear arthropathy but is now used to treat a variety of problems. Although its use has expanded substantially since the FDA's approval in 2004, the appropriateness in patients with rotator cuff disease is unclear. Questions/purposes We review the use of RTSA in patients with rotator cuff disease to (1) describe classification of rotator cuff tear reparability and the concept of a balanced shoulder; (2) explore the theory behind RTSA design relative to rotator cuff arthropathy; (3) discuss the indications and contraindications for RTSA; and (4) review published outcomes of RTSA for rotator cuff arthropathy.Methods We performed a selective review of the literature on the use of RTSA in the treatment of rotator cuff disease.Results Modern RTSA designs restore deltoid tension and a functional fulcrum to the rotator cuff deficient shoulder, which allows recovery of active shoulder elevation and effectively restores function in short-and mediumterm followup studies. Conclusions In short-term followup the RTSA relieves symptoms and restores function for patients with cuff tear arthropathy and irreparable rotator cuff tears with pseudoparalysis (preserved deltoid contraction but loss of active elevation). Severely impaired deltoid function, an isolated supraspinatus tear, and the presence of full active shoulder elevation with a massive rotator cuff tear and arthritis are contraindications to RTSA. Clinical Relevance For properly selected patients who have symptomatic and disabling rotator cuff deficiency, RTSA can result in life-changing improvements in pain, motion, function, and patient satisfaction. Level of Evidence Level V therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Indications for Reverse Total Shoulder Arthroplasty in Rotator Cuff Disease

Drake¹,

O’Connor

Edwards

2010

222

129

“…The two basic biomechanical principles of the Grammont RSA are a medialization of the glenohumeral center of rotation and a lowering of the humerus [6]. These principles reduce torque on the glenoid component and increase the deltoid lever arm, overcoming weak or absent rotator cuff musculature [5,34]. However, a number of problems and complications, attributed to the medialized design, have been reported in the literature One author (PB) declares a commercial association (Tornier) that might pose a conflict of interest in connection with the submitted article.…”

Section: Introductionmentioning

confidence: 99%

“…Each author certifies that his or her institution approved or waived approval for the human protocol for this investigation and that all investigations were conducted in conformity with ethical principles of research. [5,6,13,16,21,22,27,29,37,40,41]. Inferomedial impingement of the humeral insert against the pillar of the scapula during adduction and rotation of the arm is responsible for bone erosion and polyethylene wear (known as ''inferior scapular notching'') and has been observed in 50% to 96% of postoperative radiographs [6,7,27,29,30,32,36,41].…”

Section: Introductionmentioning

confidence: 99%

Bony Increased-offset Reversed Shoulder Arthroplasty: Minimizing Scapular Impingement While Maximizing Glenoid Fixation

Boileau

Moineau

Roussanne

et al. 2011

Self Cite

416

326

Background Scapular notching, prosthetic instability, limited shoulder rotation and loss of shoulder contour are associated with conventional medialized design reverse shoulder arthroplasty. Prosthetic (ie, metallic) lateralization increases torque at the baseplate-glenoid interface potentially leading to failure. Questions/purposes We asked whether bony lateralization of reverse shoulder arthroplasty would avoid the problems caused by humeral medialization without increasing torque or shear force applied to the glenoid component. Patients and Methods We prospectively followed 42 patients with rotator cuff deficiency treated with bony increased-offset reverse shoulder arthroplasty. A cylinder of autologous cancellous bone graft, harvested from the humeral head, was placed between the reamed glenoid surface and baseplate. Graft and baseplate fixation was achieved using a lengthened central peg (25 mm) and four screws. Patients underwent clinical, radiographic, and CT assessment at a minimum of 2 years after surgery. ResultsThe humeral graft incorporated completely in 98% of cases (41 of 42) and partially in one. At a mean of 28 months postoperatively, no graft resorption, glenoid loosening, or postoperative instability was observed. Inferior scapular notching occurred in 19% (eight of 42). The absolute Constant-Murley score improved from 31 to 67. Thirty-six patients (86%) were able to internally rotate sufficiently to reach their back over the sacrum. Conclusions Grafting of the glenoid surface during reverse shoulder arthroplasty effectively creates a long-necked scapula, providing the benefits of lateralization. Bony increased-offset reverse shoulder arthroplasty is associated with low rates of inferior scapular notching, improved shoulder rotation, no prosthetic instability and improved shoulder contour. In contrast to metallic lateralization, bony lateralization has the advantage of maintaining the prosthetic center of rotation at the prosthesis-bone interface, thus minimizing torque on the glenoid component.

“…The variables in the current prostheses have been developed to address concerns that have arisen with reverse shoulder arthroplasty. The persistent problems and high complication rate with this procedure have been described extensively in the current literature, with complications including hematoma formation [48], infection [5,15,18,45,48,49], scapular notching [28,44,45,49], instability [18,48,49], acromial insufficiency [15,48], and glenoid component failures [14,17,42,45]. Additionally, complications and patient satisfaction vary among primary cuff tear arthroplasty, revision cases, and fractures [5,15,18,45,48,49].…”

Section: Discussionmentioning

confidence: 99%

A History of Reverse Total Shoulder Arthroplasty

Flatow

Harrison

2011

191

108

Background Management of the cuff-deficient arthritic shoulder has long been challenging. Early unconstrained shoulder arthroplasty systems were associated with high complication and implant failure rates. The evolution toward the modern reverse shoulder arthroplasty includes many variables of constrained shoulder arthroplasty designs. Questions/purposes This review explores the development of reverse shoulder arthroplasty, specifically describing (1) the evolution of reverse shoulder arthroplasty designs, (2) the biomechanical variations in the evolution of this arthroplasty, and (3) the current issues relevant to reverse shoulder arthroplasty today. Methods Using a PubMed search, the literature was explored for articles addressing reverse shoulder arthroplasty, focusing on those papers with historical context. Results Results of the early designs were apparently poor, although they were not subjected to rigorous clinical research and usually reported only in secondary literature. We identified a trend of glenoid component failure in the early reverse designs. This trend was recognized and reported by authors as the reverse shoulder evolved.Authors reported greater pain relief and better function in reverse shoulder arthroplasty with the fundamental change of Grammont's design (moving the center of rotation medially and distally). However, current reports suggest lingering concerns and challenges with today's designs. Conclusions The history of reverse shoulder arthroplasty involves the designs of many forward-thinking surgeons. Many of these highly constrained systems failed, although more recent designs have demonstrated improved longevity and implant performance. Reverse shoulder arthroplasty requires ongoing study, with challenges and controversies remaining around present-day designs.