Hemiarthroplasty versus reverse shoulder arthroplasty in 4-part displaced fractures of the proximal humerus: Multicenter retrospective study

Introduction: Complex 4-part fractures of the proximal humerus are one of the most difficult fractures to manage. For several years, reverse total arthroplasty (RSA) has been proposed as an alternative to hemiarthroplasty (HA) when internal fixation is insufficient. The goal of this study was to compare the short and intermediate term results of these 2 different types of arthroplasty. Materials and methods: In a retrospective, multicenter study, 57HA and 41 RSA were reviewed after a follow-up of at least 2 years. The clinical evaluation was based on the absolute and adjusted Constant scores, Simple shoulder value (SSV) and the quick-DASH scores. The radiological assessment included standard radiological tests. Results: After a mean follow-up of 39 months, the RSA group had a significantly higher adjusted Constant score than the HA group (83% vs 73%, respectively P = 0.02). However, there was no significant difference in the absolute Constant score, the quick-DASH or the SSV scores. Active anterior elevation was better in the RSA group, while internal rotation was better in the HA group (130◦ vs 112◦, P = 0.01; sacrum vs L3, P = 0.03). There was no significant difference in external rotation (28◦ vs 23◦, P = 0.31). The rate of complications was higher in the HA group than in the RSA group (24% vs 10%, P = 0.01). The radiological rate of union of the greater tuberosity was similar in both groups (70%) and scapular notching was found in 23% of the RSA group. Conclusion: The short and intermediate term clinical outcomes are better with RSA than with HA. The complication rate is higher with HA. Nevertheless, scapular notching occurred in more than 20% of patients with RSA, suggesting that care should be taken when using this prosthesis in young, active patients

Biomechanical properties of transosseous bony Bankart repair in a cadaver model

INTRODUCTION: We compared two arthroscopic repair techniques to an intact shoulder using a biomechanical model of anterior shoulder dislocation with an anterior glenoid rim fracture (Ideberg IA fracture). We hypothesized that transosseous repair is sufficient to effectively stabilize the glenoid fracture. The primary objective was to define the mechanical properties of transosseous repair of an Ideberg IA fracture relative to an intact shoulder (control group). The secondary objective was to determine the contribution of supplemental anteroposterior screw fixation of the bone fragment. MATERIALS AND METHODS: Fifteen fresh cadaver shoulders were divided into two groups: 5 specimens in the control group and 10 in the fracture fixation group, with sequential performance of transosseous repair followed by transosseous repair+screw fixation. A fracture at the inferior portion involving more than 30% of the glenoid's surface area was made. RESULTS: The load to failure was 457 N in the control group, 277 N in the transosseous repair group and 325 N in the transosseous repair+screw fixation group. The stiffness of the constructs was 26.2N/mm for the control group, 14.6N/mm for transosseous repair and 24.6N/mm for transosseous repair+screw fixation. The difference between the two repair techniques was significant for the load to failure (p=0.02) and stiffness (p=0.001). DISCUSSION/CONCLUSION: This study showed that transosseous repair restores the shoulder's anatomy but not the mechanical strength of the native glenoid. Adding screw fixation significantly improves the construct

Outcomes of capsulolabral reconstruction for posterior shoulder instability

BACKGROUND: Surgical treatment of isolated posterior shoulder instability-a rare and often misdiagnosed condition-is controversial because of poor outcomes. Failure of physical therapy in symptomatic young athletes requires capsulolabral reconstruction or bone block procedures. The goal of this study was to report the outcomes of patients who have undergone surgical capsulolabral reconstruction and to look for risk factors that contribute to failure of this procedure. MATERIAL AND METHOD: We analyzed the outcomes of 101 patients who underwent capsulolabral reconstruction: 83 included retrospectively, 18 included prospectively. The procedures were performed alone or in combination with capsular shift, labral repair, closure of the rotator interval and notch remplissage. The primary endpoint was failure of the procedure, defined as recurrence of the instability and/or pain. We also determined the outcomes based on specific (Walch-Duplay, modified Rowe) and non-specific (Constant, resumption of activities) scores of shoulder instability. RESULTS: The results were satisfactory despite a high failure rate: 35% in the retrospective cohort with 4.8±2.6 years' follow-up and 22% in the prospective cohort with 1.1±0.3 years' follow-up. The various outcome scores improved significantly. Ninety-two percent of patients returned to work and 80% of athletes returned to their pre-injury level of sports. Eighty-five percent of patients were satisfied or very satisfied after the surgery. No risk factors for failure were identified; however, failures were more common in older patients, those who underwent an isolated procedure and those who had unclassified clinical forms. CONCLUSION: Treatment of posterior shoulder instability by capsulolabral reconstruction leads to good clinical outcomes; however, the recurrence rate is high

Posterior shoulder instability: prospective non-randomised comparison of operative and non-operative treatment in 51 patients

BACKGROUND: The management of posterior shoulder instability remains controversial. Consequently, for a symposium on this topic, the French Arthroscopy Society (SFA) conducted a prospective multicentre study comparing outcomes of operative and non-operative treatment. OBJECTIVE: To compare outcomes after operative versus non-operative treatment of posterior shoulder instability. HYPOTHESIS: The surgical treatment of posterior shoulder instability may achieve better clinical outcomes than non-operative treatment in selected patients. MATERIAL AND METHODS: Fifty-one patients were included prospectively then followed-up for 12months. Three groups were defined based on the clinical presentation: recurrent dislocation or subluxation, involuntary instability or voluntary instability that had become involuntary, and shoulder pain with instability. Of the 51 patients, 19 received non-operative therapy involving a three-step rehabilitation programme and 32 underwent surgery with a posterior bone block, labral repair and/orcapsule tightening, or bone defect filling. At inclusion and at last follow-up, the Subjective Shoulder Value (SSV), Rowe score, Walch-Duplay score, and Constant score were determined. RESULTS: The preliminary results after the first 12 months are reported here. In the non-operative and operative groups, the Constant score was 78 versus 87, the Rowe score 64 versus 88, and the Walch-Duplay score 69 versus 82, respectively. These differences were statistically significant (P<0.05). DISCUSSION: To our knowledge, this study is the first comparison of non-operative versus operative treatment in a cohort of patients with documented posterior shoulder instability. Outcomes were better with operative treatment. However, this finding remains preliminary given the short follow-up of only 1 year

Painful posterior shoulder instability: anticipating and preventing failure. A study in 25 patients.

BACKGROUND: Painful posterior shoulder instability (PPSI) is the least common of the three clinical patterns of posterior shoulder instability. PPSI is defined as pain combined with anatomical evidence of posterior instability but no instability events. MATERIAL AND METHOD: We studied a multicentre cohort of 25 patients with PPSI; 23 were identified retrospectively and had a follow-up of at least 2 years and 2 patients were included prospectively. Most patients engaged in sports. RESULTS: All 25 patients underwent surgery, which usually consisted in arthroscopic capsulo-labral reconstruction. The outcome was excellent in 43% of patients; another 43% had improvements but reported persistent pain. The pain remained unchanged or worsened in the remaining 14% of patients. Causes of failure consisted of a missed diagnosis of shoulder osteoarthritis with posterior subluxation, technical errors, and postoperative complications. The main cause of incomplete improvement with persistent pain was presence of cartilage damage. CONCLUSION: Outcomes were excellent in patients who were free of cartilage damage, bony abnormalities associated with posterior instability (reverse Hill-Sachs lesion, erosion or fracture of the posterior glenoid), technical errors, and postoperative complications

Posterior shoulder instability managed by arthroscopic acromial pediculated bone-block. Technique

In posterior shoulder instability (recurrent dislocation, involuntary posterior subluxation or voluntary subluxation that has become involuntary), surgery may be considered in case of failure of functional treatment if there are no psychological contraindications. Acromial bone-block with pediculated deltoid flap, as described by Kouvalchouk, is an alternative to iliac bone-block, enabling triple shoulder locking by the blocking effect, the retention hammock provided by the deltoid flap and posterior capsule repair. Arthroscopy allows shoulder joint exploration and diagnosis of associated lesions, with opening and conservation of the posterior capsule; it greatly facilitates bone-block positioning and capsule reinsertion. The present report describes the procedure in detail

Mise au point d’un modèle aux éléments finis de l’articulation gléno-humérale. Application à l’étude de la prothèse inversée d’épaule

Ce travail est basé sur un modèle aux éléments finis d’articulation de l’épaule. Nous avons simulé un mouvement d’abduction du bras, pour étudier la biomécanique des muscles de la coiffe des rotateurs et surtout l’arthroplastie inversée, afin de nous permettre d’optimiser la mise en place des implants, et de mieux appréhender l’origine du descellement prothétique. Étude de la transmission des contraintes imposées par les tendons de la coiffe des rotateurs à l’extrémité proximale de l’humérus : en fonction du type d’os modélisé, la pénétration en profondeur des contraintes reste faible, mais il y a une plus grande déformation dans l’os ostéoporptique à effort constant, expliquant certains phénomènes d’arrachement osseux. La platine de la prothèse inversée : quelle que soit la position d’abduction, la vis supérieure semble être soumise à des contraintes supérieures à la vis inférieure ; cette dernière travaille en traction, alors que la vis supérieure est soumise à des contraintes en compressions. Le déplacement de la vis inférieure est supérieur à celui de la vis supérieure. C’est le positionnement de la vis inférieure qui doit être privilégié lors de l’implantation d’une prothèse inversée. Distribution des contraintes autour de la tige humérale : des contraintes élevées sont observées au niveau de l’humérus distal (zone de transmission des contraintes de l’implant vers l’os) et en regard de l’aileron qui bloque l’implant en rotation. Ces contraintes sont localement importantes, mais pas suffisantes pour dépasser le seuil fracturaire osseux. Elles peuvent cependant expliquer les fractures périprothétiques et les zones préférentielles de résorption osseuse et descellement.This work is based on a finite element model of the shoulder. An abduction of the arm has been simulated to study first the biomechanics of the rotator cuff muscles, then the reversed total shoulder arthroplasty. The aim of the study is to help the surgeon to implant properly this prosthesis and to infer reasons of aseptic loosening of the implants. Analysis of the strain distribution to the humeral head tubercles by the rotator cuff tendons during abduction: the distribution of stress magnitude according to the type of bone modeled, shows that stresses are also greater in old bone, implying more deformation in old bone at constant force. It also shows that stresses do not penetrate deeply into cancellous bone. This explains some bonny avulsion of the rotator cuff tendons. Glenoid base plate study: whatever the degree of arm abduction strain applied to the superior locked screw is greater than stain applied to the inferior. This one always works in traction whereas compressions forces are applied to the superior screw. Displacement of the inferior screw is greater than the superior. In case of reversed total shoulder arthroplasty the surgeon has to secure positioning of the inferior screw. Strain distribution around the humeral stem: high strains are observed distally (transmission zone between the stem and the bone), and proximally next to the fin of the prosthesis that is dedicated to lock the implant rotation. Even if these strains are locally high they remain under the fracture threshold. Nevertheless they help us to understand periprosthetic fracture mechanisms, stress-shielding mechanisms and implant loosening

Finite element model of the glenohumeral joint,Application to the study of a reversed prothesis

Ce travail est basé sur un modèle aux éléments finis d'articulation de l'épaule. Nous avons simulé un mouvement d'abduction du bras, pour étudier la biomécanique des muscles de la coiffe des rotateurs et surtout l'arthroplastie inversée, afin de nous permThis work is based on a finite element model of the shoulder. An abduction of the arm has been simulated to study first the biomechanics of the rotator cuff muscles, then the reversed total shoulder arthroplasty. The aim of the study is to help the surge

La ligamentoplastie au court fibulaire selon Castaing dans le traitement chirurgical de l'instabilité chronique latérale de la cheville (à propos de 46 patients.)

STRASBOURG-Medecine (674822101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF