Grégory Moineau

Revision surgery of reverse shoulder arthroplasty

BACKGROUND There is limited knowledge regarding revision of reverse shoulder arthroplasty (RSA). This study assesses reasons for failure in RSA and evaluates the outcomes of revision RSA. MATERIALS AND METHODS Between 1997 and 2009, 37 patients with RSA had revision surgery. Clinical and radiologic examinations performed preoperatively and at 3 months, at 6 months, and then annually postoperatively were analyzed retrospectively. Patients were reviewed with a minimum 2-year follow-up. RESULTS The most common causes for RSA revision were prosthetic instability (48%); humeral loosening, derotation, or fracture (21%); and infection (19%). Only 2 patients (3%) had to be reoperated on for glenoid loosening. More than 1 re-intervention was performed in 11 patients (30%) because of recurrence of the same complication or appearance of a new complication. Underestimation of humeral shortening and excessive medialization were common causes of recurrent prosthetic instability. Proximal humeral bone loss was found to be a cause for humeral loosening or derotation. Previous surgery was found as a potential cause of low-grade infection. At a mean follow-up of 34 months, 32 patients (86%) had retained the RSA whereas 2 patients (6%) had undergone conversion to humeral hemiarthroplasty and 3 (8%) to a resection arthroplasty. The mean Constant score in patients who retained the RSA increased from 19 points before revision to 47 points at last follow-up (P < .001). CONCLUSIONS Even if revision may lead to several procedures in the same patient, preservation or replacement of the RSA is largely possible, allowing for a functional shoulder. Full-length scaled radiographs of both humeri are recommended to properly assess humeral shortening and excessive medialization before revision.

Epidemiology of proximal humerus fractures managed in a trauma center

Proximal humerus fractures (PHF) are osteoporotic fractures that affect women over 70 years of age. Like fractures of the femoral neck they have become a public health concern. As the population ages there is an increase in the number of people in poor general condition with an increased risk of falls on fragile bones. The incidence of these fractures has increased by 15% per year. All patients managed for PHF in our center in the past year were included in this prospective study (prospective cohort study; level 2). Three hundred and twenty-five patients were included with 329 fractures. There was a ratio of two women to one man. At the final follow-up 50 patients had died (15%) and 25 patients were lost to follow-up. The mean age was 70 years old. There were two types of risk factors. The first was fragile bones, and the second was patient specific risk of falls. The severity of the fracture increased with the age of the population. In the study by Charles S. Neer in 1970, 85% of PHF were not or were only slightly displaced, while this category percentage was only 42% in our study. Hospitalization was necessary in 43% of the cases in our study. Surgical management was necessary in 21%. This lack of relationship between the percentage of displaced fractures (58%) and the percentage of surgically treated fractures is a sign of the difficulties of managing this population, which is usually in poor general condition.

Three-dimensional measurement method of arthritic glenoid cavity morphology: feasibility and reproducibility.

INTRODUCTION Glenoid component loosening is the main complication of total shoulder arthroplasty. Better knowledge of the arthritic glenoid cavity anatomy can help in developing new implants and techniques. The goal of this study was to describe and validate the reproducibility of a CT scan-based, 3D measurement method used to describe various parameters characterizing arthritic glenoid cavity morphology. MATERIALS AND METHODS Twelve CT scans and 29 CT arthrogram were evaluated. These scans were taken from 41 patients with glenohumeral osteoarthritis who received an anatomical shoulder prosthesis. A 3D reconstruction of the scapula was performed based on the DICOM files. Following the 3D volume acquisition, points on the glenoid articular surface were manually extracted by three observers, each one three times, allowing one week between readings, to determine the inter- and intra-observer reproducibility. The intraclass correlation coefficient (ICC) was calculated on five 3D parameters that were automatically calculated: glenoïd height, glenoid width, height at maximum width glenoid version and radius of the articular surface best-fit sphere. RESULTS The intra-observer and inter-observer ICC were 0.91 to 0.99, and 0.95 to 0.99, respectively. DISCUSSION This study is the first to report on a reproducible 3D measurement method, based on CT scans, for the arthritic glenoid cavity, which derives the joint radius of curvature among other morphology parameters. These 3D measurements are advantageous because they are free of problems related to patient positioning in the CT scanner and to the choice of slices, which limits the accuracy of measurements made on slices from 2D CT scans. Three-dimensional methodology similar to ours has been validated on healthy glenoids. CONCLUSION This study confirms the reliability and good reproducibility of our method, which allows us to extend this method to a larger patient cohort and adapt this automated technology to preoperative planning software.

Prognostic Factors and Limitations of Anatomic Shoulder Arthroplasty for the Treatment of Posttraumatic Cephalic Collapse or Necrosis (Type-1 Proximal Humeral Fracture Sequelae)

BACKGROUND The aim of this study was to evaluate the prognostic factors and limitations of anatomic unconstrained shoulder arthroplasty, performed without tuberosity osteotomy, for the treatment of secondary glenohumeral arthritis following posttraumatic cephalic collapse or necrosis of the humeral head, defined as type-1 fracture sequelae. METHODS Fifty-five patients with type-1 fracture sequelae treated with anatomic shoulder arthroplasty were included in this retrospective single-center cohort study. All anatomic humeral prostheses were implanted without performing a greater tuberosity osteotomy. Glenoid resurfacing was performed in forty-four patients (80%). Clinical and radiographic analysis was performed at a mean of fifty-two months (range, twenty-four to 180 months) postoperatively. RESULTS Four reoperations (7%) were performed, including two revisions in patients who required glenoid resurfacing because of glenoid erosion after hemiarthroplasty. At the time of the latest follow-up, 93% of patients were satisfied or very satisfied, and the mean Subjective Shoulder Value (SSV) was 81%. There were significant improvements in the mean Constant score (from 32 to 69 points), active anterior elevation (from 88° to 141°), external rotation (from 6° to 34°), and internal rotation (from the buttock to L3). Significantly poorer results were associated with proximal humeral deformity in varus and with fatty infiltration of the rotator cuff muscles. Patients with proximal humeral deformity, specifically varus or valgus malunion of the greater tuberosity, had a mean Constant score that was 10 points lower and active elevation that was almost 20° less than patients with no such deformity. The poorest results were observed in patients with varus malunion. CONCLUSIONS Our study confirmed that the outcomes of anatomic shoulder arthroplasty for the treatment of type-1 fracture sequelae are good and predictable when deformation of the proximal humerus is acceptable(i.e., when no greater tuberosity osteotomy is necessary). The results were negatively affected by proximal humeral varus deformity and by fatty infiltration of the rotator cuff on imaging studies. In such cases, reverse shoulder arthroplasty may be more appropriate, especially in elderly patients.

Ectopic insertion of the pectoralis minor: implication in the arthroscopic treatment of shoulder stiffness.

Although ectopic insertion of the pectoralis minor has been previously described in the literature, the role of such anatomical variations in producing shoulder symptoms (i.e., pain and/or stiffness) remains controversial. We describe here a case of shoulder stiffness in which an ectopic insertion of the pectoralis minor over the supraspinatus tendon was found to be the main reason for severe contracture in external rotation and anterior thoracic pain. During arthroscopy, external rotation could not be restored despite anterior and inferior capsulotomy and release of the capsule of the rotator interval. Complete restoration of the passive external rotation was obtained only after complete release of the pectoralis minor from the supraspinatus. This observation underlines the importance of recognising such an anatomical variation when performing an arthroscopic arthrolysis in a stiff shoulder.

Anatomical total shoulder arthroplasty in young patients with osteoarthritis

Aims Controversy about the use of an anatomical total shoulder arthroplasty (aTSA) in young arthritic patients relates to which is the ideal form of fixation for the glenoid component: cemented or cementless. This study aimed to evaluate implant survival of aTSA when used in patients aged < 60 years with primary glenohumeral osteoarthritis (OA), and to compare the survival of cemented all‐polyethylene and cementless metal‐backed glenoid components. Materials and Methods A total of 69 consecutive aTSAs were performed in 67 patients aged < 60 years with primary glenohumeral OA. Their mean age at the time of surgery was 54 years (35 to 60). Of these aTSAs, 46 were undertaken using a cemented polyethylene component and 23 were undertaken using a cementless metal‐backed component. The age, gender, preoperative function, mobility, premorbid glenoid erosion, and length of follow‐up were comparable in the two groups. The patients were reviewed clinically and radiographically at a mean of 10.3 years (5 to 12, SD 26) postoperatively. Kaplan‐Meier survivorship analysis was performed with revision as the endpoint. Results A total of 26 shoulders (38%) underwent revision surgery: ten (22%) in the polyethylene group and 16 (70%) in the metal‐backed group (p < 0.0001). At 12 years’ follow‐up, the rate of implant survival was 74% (SD 0.09) for polyethylene components and 24% (SD 0.10) for metal‐backed components (p < 0.0002). Glenoid loosening or failure was the indication for revision in the polyethylene group, whereas polyethylene wear with metal‐on‐metal contact, instability, and insufficiency of the rotator cuff were the indications for revision in the metal‐backed group. Preoperative posterior subluxation of the humeral head with a biconcave/retroverted glenoid (Walch B2) had an adverse effect on the survival of a metal‐backed component. Conclusion The survival of a cemented polyethylene glenoid component is three times higher than that of a cementless metal‐backed glenoid component ten years after aTSA in patients aged < 60 years with primary glenohumeral OA. Patients with a biconcave (B2) glenoid have the highest risk of failure.