Revision of reversed shoulder arthroplasty : is a reoperation possible?

Introduction. As the number of reversed shoulder arthroplasty (RSA) procedures increases, the revision rate will also increase. In case of severe bone insufficiency, instability or infection of the primary RSA, revision to another RSA is preferable but not always possible. Hemiarthroplasty (HA), spacers and resection arthroplasty (RA) have been described in this indication. Materials and methods. Between 2004 and 2016, 20 shoulders in 19 patientswere treated at Ghent University Hospital for failed revision of RSA. Nine received a megahead prosthesis, a spacerwas implanted in 6, and 5 underwent RA. Results. Indications for implantation of a megahead prosthesis were loosening RSA (n = 5), infection (n = 4), dislocation (n = 1) and nerve irritation (n = 1). Improvement of range ofmotionwas observed. Anterosuperior migration of the prosthesis was noted in 2 patients. Another 2 patients were ultimately revised to RSA. Seven permanent spacerswere implanted for infection, of which 2 remain in place till today. The other 5 were revised to RSA. Of the 5 patients treated with RA, 3 were revised further on to RSA, resulting in pain relief and regain of function. Discussion. Our study shows that amegahead prosthesis has better functional results than RA, but is inferior to RSA. Due to increasing surgical experience and improving technique, 9 patients could ultimately be reconverted to another RSA. A review of current literature is presented. In HA and RA, the functional results are poor, and pain relief is uncertain. Results of spacers are variable and can be satisfactory. Arthrodesis is a last resort. Conclusion. In our case series study, a hemiarthroplasty can be performed in case of failure of RSA. However, the results are inferior to another RSA

Relationship of the medial clavicular head to the manubrium in normal and symptomatic degenerated sternoclavicular joints

Background: Clavicular prominence is common in patients with symptomatic degenerative sternoclavicular arthritis. It is unclear if this is caused by enlargement or subluxation of the clavicle. The aim of this report is to describe a reproducible measurement technique to evaluate the relationship of the medial clavicular head to the manubrium. Methods: One hundred normal sternoclavicular joints, twenty-five sternoclavicular joints with symptomatic degenerative arthritis, and twenty-five non-symptomatic sternoclavicular joints on the contralateral side were studied with three-dimensional (3D) reconstruction with use of computer modeling. The greatest width (anterior-posterior distance) and height (superior-inferior distance) of the clavicle in the sagittal plane were measured, and the positions of the anterior and superior borders of the medial clavicle and their distances to the frontal and axial planes, respectively, were evaluated. The ratio of the anterior-posterior distance to the anterior-frontal plane distance was measured to evaluate the anterior-posterior position of the clavicle and the ratio of the superior-inferior distance to the superior-axial plane distance was measured to evaluate its superoinferior position. If the ratio was not in the 95% normal range, the clavicle was defined as subluxated. The reproducibility of this technique was evaluated on the basis of the interobserver and intraobserver reliability. Results: This technique showed good interobserver and intraobserver reliability. The mean anterior-posterior and superior-inferior distances were significantly larger in association with symptomatic sternoclavicular arthritis than in the normal sternoclavicular joints (p < 0001). The clavicle was subluxated anteriorly in twenty-two of the twenty-five cases of symptomatic sternoclavicular arthritis, but it was not subluxated superiorly. Conclusions: The medial clavicular head in patients with degenerative sternoclavicular arthritis is significantly larger than it is in the normal population, and it is usually subluxated anteriorly

Medium to long-term outcome of thoracoscapular arthrodesis with screw fixation for facioscapulohumeral muscular dystrophy

Background: Shoulder girdle muscle weakness is the most constant feature of facioscapulohumeral muscular dystrophy and leads to scapular winging. Mechanical fixation of the scapula to the thoracic wall provides a stable fulcrum on which the deltoid muscle can exert its action on the humerus. The aim of this study was to evaluate the medium to long-term outcome of thoracoscapular arthrodesis with screw fixation (the modified Howard-Copeland technique). Methods: All patients with facioscapulohumeral dystrophy who underwent thoracoscapular arthrodesis with screw fixation and bone-grafting from July 1997 to July 2010 were retrospectively reviewed. Preoperative and postoperative clinical assessment included active shoulder elevation, the Constant score, a patient satisfaction score, and cosmetic satisfaction. Union was determined both clinically and radiographically. Results: Thoracoscapular arthrodesis was performed in thirty-five shoulders in twenty-four patients; eleven patients underwent bilateral procedures. The principal study group consisted of thirty-two shoulders in twenty-one patients with a minimum follow-up of twenty-four months (Mean, eighty-eight months; range, twenty-four to 174 months). The mean Constant score increased from 30 (range, 17 to 41) preoperatively to 61 (range, 30 to 90) postoperatively. The mean satisfaction score increased from 1 (range, 0 to 4) to 8.4 (range, 4 to 10). Early complications consisted of one pneumothorax, one superficial wound infection, and four early failures, two of which were associated with noncompliance with the postoperative regimen. Late complications consisted of one posttraumatic fracture resulting in loosening and one painful nonunion; both were treated successfully with revision. Conclusions: Thoracoscapular arthrodesis with screw fixation prevented scapular winging and improved short-term and long-term shoulder function in patients with facioscapulohumeral dystrophy. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence

Consequences of reaming with flat and convex reamers for bone volume and surface area of the glenoid : a basic science study

Background: The effect of reaming on bone volume and surface area of the glenoid is not precisely known. We hypothesize that (1) convex reamers create a larger surface area than flat reamers, (2) flat reamers cause less bone loss than convex reamers, and (3) the amount of bone loss increases with the amount of version correction. Methods: Reaming procedures with different types of reamers are performed on similar-sized uniconcave and biconcave glenoids created from Sawbones foam blocks. The loss of bone volume, the size of the remaining surface area, and the reaming depth are measured and evaluated. Results: Reaming with convex reamers results in a significantly larger surface area than with flat reamers for both uniconcave and biconcave glenoids (p = 0.013 and p = 0.001). Convex reamers cause more bone loss than flat reamers, but the difference is only significant for uniconcave glenoids (p = 0.007). Conclusions: In biconcave glenoids, convex reamers remove a similar amount of bone as flat reamers, but offer a larger surface area while maximizing the correction of the retroversion. In pathological uniconcave glenoids, convex reamers are preferred because of the conforming shape

Predictors of shoulder degeneration in the KwaZulu-Natal population of South Africa

The critical shoulder angle and acromion index are conventional radiological tools employed as predictors of shoulder degeneration. As they represent the static components of glenohumeral stability, the scapulo-humeral geometry and underlying subacromial tissue appear as the resultant cause-effect factors. Consequently. the purpose of this study was to investigate the critical shoulder angle and acromion index as interrelated parameters within the South African population. The measurement of both biomechanical parameters was conducted on two-hundred and sixty (n = 260) true AP radiographs. This was a cross-sectional study that also incorporated the demographic representation of the population group which was analysed accordingly. The mean values recorded for both the critical shoulder angle (36.31 +/- 5.84 degrees) and acromion index (0.74 +/- 0.13) suggested rotator cuff arthropathy. The results confirmed the theories of Nyffeler et al. (2006) and Moor et al. (2012) who alluded to glenoid inclination and the acromial coverage over the humeral head. A significant proportionality correlation, verified by a P value of 0.000, was established between the acromion index and critical shoulder angle which may assist to differentiate between normal asymptomatic shoulders and those with cuff disease. Furthermore, these predictors of shoulder degeneration may present as a preventative tool against tear progression

Improving the surface properties of an UHMWPE shoulder implant with an atmospheric pressure plasma jet

Insufficient glenoid fixation is one of the main reasons for failure in total shoulder arthroplasty. This is predominantly caused by the inert nature of the ultra-high molecular weight polyethylene (UHMWPE) used in the glenoid component of the implant, which makes it difficult to adhesively bind to bone cement or bone. Previous studies have shown that this adhesion can be ameliorated by changing the surface chemistry using plasma technology. An atmospheric pressure plasma jet is used to treat UHMWPE substrates and to modify their surface chemistry. The modifications are investigated using several surface analysis techniques. The adhesion with bone cement is assessed using pull-out tests while osteoblast adhesion and proliferation is also tested making use of several cell viability assays. Additionally, the treated samples are put in simulated body fluid and the resulting calcium phosphate (CaP) deposition is evaluated as a measure of the in vitro bioactivity of the samples. The results show that the plasma modifications result in incorporation of oxygen in the surface, which leads to a significant improved adhesion to bone cement, an enhanced osteoblast proliferation and a more pronounced CaP deposition. The plasma-treated surfaces are therefore promising to act as a shoulder implant

Diagnostic value of active protraction and retraction for sternoclavicular joint pain

Background: Sternoclavicular joint (SCJ) arthropathy is an uncommon cause of mechanical pain. The aim of this study is to evaluate the diagnostic value of two active clinical tests for localizing the sternoclavicular joint as the source of mechanical pain. Methods: All patients between June 2011 and October 2013 that visited the orthopedic departments of three hospitals with atraumatic pain in the area of the SC joint were evaluated. Local swelling, pain at palpation, pain during arm elevation and two newly described tests (pain during active scapular protraction and retraction) were evaluated. CT images were evaluated. The patients were then divided into two groups according to whether they had a >= 50% decrease in pain following the SCJ injection. Sensitivity and specificity for local swelling, the four clinical tests and CT-scan were measured. Results: Forty eight patients were included in this study and SC joint pain was confirmed in 44. The tests with highest sensitivity were pain on palpation, (93% sensitivity) and pain during active scapular protraction (86%). CT-scan showed a sensitivity of 84%. Local swelling showed a high specificity (100%). Conclusion: Pain at the SCJ during active scapular protraction is a good clinical diagnostic tool for SC arthropathy

Can an extracorporeal glenoid aiming device be used to optimize the position of the glenoid component in total shoulder arthroplasty?

Purpose: Successful total shoulder arthroplasty (TSA) requires a correct position of the glenoid component. This study compares the accuracy of the positioning with a new developed glenoid aiming device and virtual three-dimensional computed tomography (3D-CT) scan positioning. Materials and Methods: On 39 scapulas from cadavers, a K-wire (KDev) was positioned using the glenoid aiming device. It consists of glenoid components connected to the aiming device, which cover 150 degrees of the inferior glenoid circle, has a fixed version and inclination and is available with several different radii. The aiming device is stabilized at the most medial scapular point. The K-wire is drilled from the center of the glenoid component to this most medial point. All scapulas were also scanned with CT and 3D reconstructed. A virtual K-wire (Kct) was positioned in the center of the glenoid and in the scapular plane. Several parameters were compared. Radius of the chosen glenoid component (rDev) and the virtual radius of the glenoid circle (rCT), spinal scapular length with the device (SSLdev) and virtual (SSLct), version and inclination between KDev and Kct, difference between entry point and exit point ("Matsen"-point). Results: Mean rDev: 14 mm +/- 1.7 mm and mean rCT: 13.5 mm +/- 1.6 mm. There was no significant difference between SSLdev (110.6 mm +/- 7.5 mm) and SSLct (108 mm +/- 7.5 mm). The version of KDev and Kct was -2.53 degrees and -2.17 degrees and the inclination 111.29 degrees and 111.66 degrees, respectively. The distance between the "Matsen-point" device and CT was 1.8 mm. Conclusion: This glenoid aiming device can position the K-wire on the glenoid with great accuracy and can, therefore, be helpful to position the glenoid component in TSA. The level of evidence: II