Background Scapular notching is a common observation during radiological follow-up of reverse shoulder arthroplasty. The purpose of this study was to evaluate the effect of glenosphere design and ...humeral component retroversion on movement amplitude in the scapular plane and inferior scapular impingement. Materials and methods The Aequalis Reversed Shoulder Prosthesis (Tornier) was implanted into 40 cadaver shoulders. On the glenoid side, 8 different combinations were tested: 36-mm glenosphere: centered (standard), eccentric, with an inferior tilt, or with the center of rotation (COR) lateralized by 5 or 7 mm; and 42-mm centered glenosphere: used alone or with the COR lateralized by 7 or 10 mm. The humeral component was positioned in 0°, 10°, 20°, 30°, and 40° of retroversion. Maximum adduction and abduction were measured when inferior impingement and superior impingement, respectively, were detected. Results The average increase in abduction amplitude was 10° and inferior impingement occurred 18° later with a 42-mm glenosphere, especially when it was lateralized by 10 mm, relative to a 36-mm centered glenosphere ( P < .05). These 2 combinations provided a 28° increase in the movement amplitude in the scapular plane. Positioning of the humeral component in 10° or 20° of retroversion or in anatomical retroversion was most effective at avoiding inferior impingement but had less effect on abduction range of motion (except with the 42-mm glenosphere). Conclusion Our study confirmed published results with various glenosphere designs but was unique in describing the effect of humeral retroversion on scapular impingement. Inferior scapular notching can be most effectively prevented by using large-diameter glenospheres with lateralized COR and by making sure to replicate the patient's native humeral retroversion.
Scapular notching in reverse shoulder arthroplasty Lévigne, Christophe, MD; Boileau, Pascal, MD; Favard, Luc, MD ...
Journal of shoulder and elbow surgery,
11/2008, Volume:
17, Issue:
6
Journal Article
Peer reviewed
The causes and consequences of scapular notching after reverse shoulder arthroplasty (RSA) were investigated in 326 consecutive patients (337 shoulders) undergoing RSA between 1991 and 2003. Patients ...underwent 269 (80%) primary RSAs and 68 revisions of unconstrained shoulder prosthesis. At last follow-up (average, 47 months; range, 24-120 months) 62% had scapular notching. Notching frequency and extension were correlated to the length of follow-up ( P = .0005). Notching was more frequent in cuff tear arthropathy ( P = .0004), grade 3 or 4 fatty infiltration of the infraspinatus ( P = .01), and narrowed acromiohumeral distance ( P < .0001). Glenoids preoperatively oriented superiorly were more at risk for notching ( P = .006). More notching occurred when the RSA was implanted using an anterosuperior approach vs a deltopectoral approach ( P < .0001). Notching was correlated with humeral radiolucencies in proximal zones ( P < .0001) and with glenoid radiolucent lines ( P < .0001). Positioning of the baseplate definitely influences scapular notching. High positioning of the baseplate and superior tilting must be avoided.
Introduction Our purpose was to evaluate if, in case of aseptic glenoid loosening and failure in anatomical total shoulder arthroplasty (TSA), revision by a reverse shoulder arthroplasty (RSA) is a ...reliable therapeutic option. Methods Retrospective multicenter cohort study of 37 consecutive anatomical TSA revised by RSA for aseptic glenoid loosening or failure. The decision to implant a RSA was related to the presence of associated complications: rotator cuff tears (n = 24), subscapularis insufficiency (n = 29), prosthetic instability (n = 13), and glenoid bone deficiency (n = 37). The patients were reviewed clinically and radiographically at a mean follow-up of 47 months (range, 24-104). Results Eighty-six percent of the patients were satisfied or very satisfied. The average Constant score increased from 24 to 55 pts ( P < .0001) and active anterior elevation from 68° to 121° ( P < .0001). Twenty-two of the 29 (76%) associated bone grafts were incorporated in the glenoid. Eight patients (21%) needed a subsequent reoperation because of recurrent or new complications: glenoid loosening (n = 3), prosthetic anterior instability (n = 3), and humeral subsidence (n = 2); the reverse prosthesis had to be converted to a hemiarthroplasty in 1 patient and removed in another. Conclusion Revision with a RSA is a reliable therapeutic option which provides the double benefit of glenoid bone stock reconstruction by fixing the bone graft with the help of the baseplate and screws and of solving the problem of soft tissue insufficiency and prosthetic instability. However, surgeons should be aware that the rate of postoperative complications and subsequent reoperations is high, and that the surgical technique is demanding.
Hypothesis Reverse shoulder prostheses depend on deltoid function. An injury to the acromion, either fracture or meso-acromion, or deltoid injury, may affect the outcomes of patients after receiving ...a reverse shoulder prosthesis. Methods Four-hundred and fifty-seven consecutive reverse shoulder prostheses were implanted between January 1992 and June 2003 by one of seven surgeons in five separate centers. Forty-one patients were noted to have a pre-operative lesion of the acromion or scapular spine. Twenty-three presented with an os acromiale (meso-acromion). Seventeen had fracture or fragmentation of the acromion. One patient had a pseudarthrosis of the scapular spine. Results Preoperative acromial pathology, surgical approach, and amount of inferior acromial tilt did not diminished postoperative range of motion, Constant score, or subjective results when compared to patients without acromial pathology. In contrast, the four patients with postoperative acromial spine fractures had inferior results with respect to functional and subjective results. Conclusion Preoperative acromial lesions are not a contraindication to reverse shoulder arthroplasty. Postoperative fracture of the acromial spine has a significant effect on results and treatment is uncertain. Level of evidence Level 3; Therapeutic retrospective case control study.
Background An association between massive rotator cuff tear (RCT) and suprascapular nerve neuropathy has previously been suggested. The anatomic course of the suprascapular nerve is relatively fixed ...along its passage. Thus, injury to the nerve by trauma, compression, and iatrogenic reasons is well documented. However, the association between retraction of the RCT and development of neuropathy of the suprascapular nerve remains unclear. We aimed to prospectively evaluate the suprascapular nerve for preoperative neurodiagnostic abnormalities in shoulders with massive RCT. Methods and materials A prospective study was performed in 2 centers. Fifty patients with retracted tears of both supraspinatus and infraspinatus were evaluated. This was confirmed with preoperative computed tomography arthrography, and the fatty infiltration of the affected muscles was graded. Forty-nine preoperative electromyograms were performed in a standardized fashion and the results analyzed twice. Results Of 49 shoulders, 6 (12%) had neurologic lesions noted on electromyography: 1 suprascapular nerve neuropathy, 1 radicular lesion of the C5 root, 1 affected electromyogram in the context of a previous stroke, and 3 cases of partial axillary nerve palsy with a history of shoulder dislocation. No difference or diminution of the latency or amplitude of the electromyographic curve was found in the cases that presented significant fatty infiltration. Conclusion This study did not detect a suprascapular lesion in the majority of cases of massive RCT. With a low association of neuropathy with massive RCT, we find no evidence to support the routine practice of suprascapular nerve release when RCT repair is performed.
Background The concept of free interposition arthroplasty proved successful for small joints of the hand, wrist, and foot, particularly after the use of implants coated with pyrocarbon, which ...enhanced their tribologic and elastic properties. The present study reports preliminary outcomes of a pyrocarbon-coated interposition shoulder arthroplasty (PISA) implant. Methods This was a prospective study of 67 consecutive patients who underwent shoulder PISA at 9 centers. The mean age at surgery was 51 years, with only 12 patients older than 60 years. The indications for surgery were primary glenohumeral arthritis in 42, avascular necrosis in 13, and secondary arthritis in 12 patients. Results Revision surgery was performed in 7 patients (10.4%), 2 (3.0%) were lost to follow-up, and the outcome assessments were incomplete in 3 (4.4%). This left 55 patients, aged 49.3 ± 12.0 years, with complete outcomes assessments at a mean follow-up of 26.8 ± 3.4 months. The Constant score improved from 34.1 ± 15.1 preoperatively to 66.1 ± 19.7 postoperatively. The radiographic findings revealed erosion in 6 glenoids and thinning of 3 humeral tuberosities. Conclusion In a cohort of young arthritic patients, PISA renders clinical scores and implant survival comparable to those of hemishoulder arthroplasty but remain inferior to those results reported for total shoulder arthroplasty. The study enabled identification of contraindications and potential causes of failure that wererelated to the concept of free interposition and smaller radius of curvature of the sphere. Until long-term results are available, this type of innovative implant should remain to be tested in a few specialized shoulder centers.
Background In a retrospective multicenter study, we evaluated the efficiency and outcomes of the different therapeutic options for infection after reversed shoulder arthroplasty. Methods Thirty-two ...patients were reoperated on for infection after reversed shoulder arthroplasty between 1996 and 2011. The mean age was 71 (55-83) years. The involved implants were primary prostheses in 23 cases and revision prostheses in 9 cases. The average preoperative Constant score was 34 (11-69). Six of these patients needed 2 successive procedures. A total of 38 procedures were performed: débridement (13), 1-stage (5) or 2-stage revision (14), or implant removal (6). At last follow-up (mean, 36 months; range, 12-137 months), every patient had clinical, biologic, and radiographic evaluation. Results Infections were largely caused by coagulase-negative staphylococci (56%) and Propionibacterium acnes (59%). The complication rate was 26%. At last follow-up, 26 patients were free of infection (81%). The final Constant score was 46 (12-75). After débridement with implant retention, the mean Constant score was 51 (29-75), but the healing rate was only 54%. Implant revision (1 or 2 stage) led to better functional results than implant removal (46 vs. 25; P = .001), with similar healing rates (73% and 67%, respectively). Patients with low initial impairment (Constant score > 30) were not significantly improved by surgical treatment. Conclusion Débridement is the less aggressive option but exposes patients to healing failure. It should be proposed as a first treatment attempt. Revision of the implant is technically challenging but preserves shoulder function, with no higher rate of residual infection compared with implant removal.
Hypothesis and background Reimplantation of a new glenoid component for symptomatic glenoid failure after total shoulder arthroplasty (TSA) is a well-established surgical strategy. In case of aseptic ...glenoid loosening or failure, revision of TSA by reimplantation of a cemented glenoid implant would be a reliable therapeutic option. Materials and methods This retrospective multicenter study included 42 TSAs with symptomatic failed glenoids revised by reimplantation of an all–polyethylene (PE), cemented glenoid component. All patients were reviewed clinically and radiologically, with a mean follow-up of 74 months. Results The failed initial glenoid component was metal backed in 32 cases and PE cemented in 10. The main cause of glenoid failure was component loosening in 19 cases (46%) and PE wear or dissociation in 23 (54%). Associated complications were very frequent, including rotator cuff tears, subscapularis insufficiency, and prosthesis instability. At last follow-up, 7 patients (17%) had already been re-revised because of symptomatic recurrent glenoid loosening. The overall rate of recurrent glenoid loosening (re-revision plus radiologic loosening) was 67%. Soft-tissue problems and prosthetic instability were significantly associated with recurrent loosening. Of the 10 associated bone grafts performed during the revision procedure, all were partially or totally lysed. At follow-up, the mean Constant score was 57 points (gain of 16 points) and the mean active anterior elevation was 125° (gain of 19°). Conclusion This study suggests that revision of a TSA with reimplantation of an all-PE cemented glenoid component does not solve the problem of glenoid loosening. Soft-tissue failure and prosthetic instability are underestimated preoperatively and may explain, in part, the high rate of recurrent glenoid loosening.
In vitro data demonstrate the potential benefits of the pyrocarbon as a bearing material against cartilage or bone. And pyrocarbon-free interposition arthroplasty has been used with positive outcomes ...for over 10 years for hand and wrist joint replacements. This study reports the midterm results of a Pyrocarbon Interposition Shoulder Arthroplasty (PISA) in primary and secondary glenohumeral osteoarthritis and in avascular osteonecrosis.
This prospective noncontrolled, multicenter study included 67 consecutive patients who underwent PISA in France and Sweden.
A cohort of 48 patients, aged 50 ± 12 years, was available for clinical assessment at a mean follow-up of 67.6 ± 9.3 months. A favorable change was reported with a mean absolute Constant score improvement of 32 ± 20 points. The highest Constant score improvement was observed in patients with avascular osteonecrosis (42 ± 18 points; P ≤ .0001). Between the earliest and the latest follow-up, radiographic analyses revealed only 2 major glenoid erosions and 4 tuberosity thinnings and thus that 86.4% of 44 shoulders remained stable with no or minor radiologic evolutions. The survival rate was 84 % at 65 months of follow-up considering all causes of revision.
The radiographic findings seem to confirm the interest of pyrocarbon in preserving bony surfaces. But the risk of tuberosity thinning suggests considering the use of PISA with caution in most degenerative glenohumeral joint pathologies, although the midterm outcomes highlight PISA as a suitable solution for patients presenting with posttraumatic osteonecrosis without malunion of the tuberosities and with an intact rotator cuff.