Stemless Anatomic and Reverse Shoulder Arthroplasty in Patients under 55 years of age with Primary Glenohumeral Osteoarthritis: An analysis of the Australian Orthopaedic Association National Joint Replacement Registry at five years.

BACKGROUND: Primary glenohumeral osteoarthritis in young patients poses challenging treatment decisions. Arthroplasty options have different failure profiles and implant survivorship patterns. This registry study aims to analyze the cumulative per cent revision rate (CPR) of different types of arthroplasties conducted for primary osteoarthritis in patients under 55 years of age. METHODS: This comparative observational national registry study included all shoulder arthroplasty for osteoarthritis in patients under 55 years of age undertaken between January 1st, 2005, and December 31st, 2022. Partial hemi resurfacing and hemi stemless procedures were excluded. The cumulative percentage of revision (CPR) was determined using Kaplan-Meier estimates of survivorship and hazard ratios (HR) from Cox proportional hazard models adjusted for gender. Reasons for revision of each type of arthroplasty and cumulative incidence of revision diagnoses were analyzed. RESULTS: 2111 primary shoulder arthroplasties were compared. Glenoid erosion is the predominant cause of revision for humeral resurfacing (29.8%) and hemiarthroplasty (35.5%). Instability is the predominant cause of revision for stemmed anatomic total shoulder arthroplasty (ATSA) and reverse total shoulder arthroplasty (RTSA), while loosening is the predominant cause of revision for stemless ATSA. The 6-year CPR is 12.8% for humeral resurfacing (HRA), 14.1% for hemiarthroplasty (HA), 12.4% for stemmed (ATSA), 7.0% for stemless ATSA, and 6.5% for (RTSA). Stemmed ATSA had a higher revision rate than RTSA (entire period HR=2.04 (95% confidence interval (CI) 1.16, 3.57), p=0.012). In contrast, the revision rate of stemless ATSA was not different from RTSA (HR =1.05 (95% CI 0.51, 2.19), p=0.889). Males outnumber females for all shoulder arthroplasty categories. DISCUSSION: RTSA and stemless ATSA are viable options in young patients with primary osteoarthritis. Their short-to medium-term revision rates are comparable to those of older patients and lower than those associated with HRA, HA, and stemmed ATSA. CONCLUSION: In the predominantly male patient population under the age of 55, reverse shoulder arthroplasty and stemless ATSA have a lower short-term revision risk than stemmed ATSA.

Qualitative analysis of the Supraspinatus muscle fatty infiltration on MRI - Correlation of the Tangent sign with Goutallier grade at the Y view and Medial Scapular border in large retracted rotator cuff tears.

BACKGROUND: Surgically repairing rotator cuff tears with a higher extent of fatty infiltration is controversial. Current evidence supports performing rotator cuff repair in patients exhibiting Goutallier stage 3-4 fatty infiltration. However, the presence of retraction complicates accurate assessment using the Goutallier Classification, particularly on the lateral Y-view. A shift towards classifying fatty infiltration in more medial regions may enhance the precision of tissue quality quantification. The objective of this study was to analyze the uniformity of fatty infiltration within the entire supraspinatus muscle using the Goutallier Classification across three scapular Y-view sections and to examine the association between Goutallier grade, tangent sign, and modified Patte stage. METHODS: A retrospective evaluation was conducted on preoperative magnetic resonance imaging (MRI) scans from a consecutive series of 97 patients who had previously undergone arthroscopic rotator cuff repairs. Three supraspinatus sections on the MRI sagittal plane were identified: the lateral Y-view (section one), a medial section at the suprascapular notch anatomical landmark (section two), and a section 3 cm medial from the suprascapular notch Medial Scapular Body (section three). Goutallier grade, tangent sign, and modified Patte stage were used to evaluate fatty infiltration, muscle atrophy, and tendon retraction, respectively. RESULTS: Section one had the highest Goutallier grade, while section three had the lowest. Intra-observer rest retest reliability analysis showed excellent consistency in all sections with section one (ICC=0.920, 95% CI), section two (ICC=0.917, 95% CI), and section three (ICC=0.923, 95% CI) for Goutallier grade. Inter-observer reliability analysis also revealed excellent consistency in sections one (ICC=0.951, 95% CI), section two (ICC=0.949, 95% CI), and section three (ICC=0.922, 95% CI) for Goutallier grade. A strong correlation was observed between Goutallier grade and modified Patte stage (τb=0.43-0.56, p=0.001), and between Goutallier grade and tangent sign (τb=0.43-0.54, p=0.001) across all sections. CONCLUSION: The severity of fatty infiltration within the supraspinatus muscle belly is inconsistent, with the lateral portion being the most severe and the medial portion the least severe. Goutallier grade demonstrates a strong correlation with tangent sign and modified Patte stage. This suggests that tendon retraction results in a potential overestimation in the amount of fatty infiltration defining some tears unjustly irreparable when measuring at the traditionally described lateral Y-view position compared with 3cm medial.

Medial scapular body (MSB) Goutallier classification: MRI-based reliability and validity of evaluation of the Goutallier classification for grading fatty infiltration of the rotator cuff.

BACKGROUND: The degree of atrophy and fatty infiltration of rotator cuff muscle belly is a key predictor for cuff repairability. Traditionally, Goutallier grading of fatty infiltration is assessed at sagittal scapular Y-view. Massive rotator cuff tears are associated with tendon retraction and medial retraction of cuff musculature, resulting in medialization of the muscle bulk. Thus, standard Y-view can misrepresent the region of interest and may misguide clinicians when assessing repairability. It is hypothesized that by assessing the muscle belly with multiple medial sagittal magnetic resonance imaging (MRI) sections at the medial scapular body, the Medial Scapular Body-Goutallier Classification (MSB-GC) will improve reliability and repeatability, giving a more representative approximation to the degree of fatty infiltration, as compared with the original Y-view. METHODS: Fatty infiltration of the rotator cuff muscles were classified based on the Goutallier grade (0-4) at 3 defined sections: section 1, original Y-view; section 2, level of suprascapular notch; and section 3, 3 cm medial to the suprascapular notch on MRI scans. Six subspecialist fellowship-trained shoulder surgeons and 3 musculoskeletal radiologists independently evaluated deidentified MRI scans of included patients. RESULTS: Of 80 scans, 78% (n = 62) were massive cuff tears involving the supraspinatus, infraspinatus, and subscapularis tendons. Interobserver reliability (consistency between observers) for Goutallier grade was excellent for all 3 predefined sections (range: 0.87-0.95). Intraobserver reliability (repeatability) for Goutallier grade was excellent for all 3 sections and 4 rotator cuff muscles (range: 0.83-0.97). There was a moderate to strong positive correlation of Goutallier grades between sections 1 and 3 and between sections 2 and 3 and these were statistically significant (P < .001). There was a reduction in the severity of fatty infiltration on the Goutallier classification from sections 1 to 3 across all muscles: 42.5% of both supraspinatus and infraspinatus were downgraded by 1, 20% of supraspinatus and 3.8% of infraspinatus were downgraded by 2, and 2.5% of supraspinatus were downgraded by 3. CONCLUSION: This study found that applying the Goutallier classification to more medial MRI sections (MSB-GC) resulted in assignment of lower grades for all rotator cuff muscles. Additionally, this method demonstrated excellent test-retest reliability and repeatability. Inclusion of a more medial view or whole scapula on MRI, especially in advanced levels of tear retraction, could be more reliable and representative for assessment of the degree of fatty infiltration within the muscle bulk that could help predict tear repairability and therefore improve clinical decision making, which should be studied further in clinical studies.

All-Arthroscopic Supraspinatus and Infraspinatus Muscle Advancement Leads to High Healing Rate and Excellent Outcomes in Patients With Massive, Retracted Rotator Cuff Tears, Even in Patients With Pseudoparalysis.

PURPOSE: To evaluate the clinical and radiographic outcomes of an all-arthroscopic rotator cuff repair technique involving muscle advancement and double-layer lasso loop (DLLL) repair for massive, retracted posterosuperior cuff tears. METHODS: This was a retrospective case series of patients with massive, retracted posterosuperior cuff tears who underwent the all-arthroscopic muscle advancement technique from March 2017 to September 2021, with a minimum follow-up of 12 months. Key steps included suprascapular nerve release, advancement of the supraspinatus and infraspinatus muscles, and DLLL repair. Preoperative and postoperative visual analog scale score for pain, American Shoulder and Elbow Surgeons (ASES) shoulder score, Constant score, University of California, Los Angeles (UCLA) shoulder score, active range of motion, and strength were compared. Preoperative and postoperative structural radiologic characteristics were analyzed. RESULTS: We evaluated 43 shoulders in 38 patients with a mean follow-up period of 18.8 months (range, 12-55 months). Of the 43 shoulders, 4 showed repair failure (9.3% retear rate). Visual analog scale, ASES, Constant, and UCLA scores significantly improved (P < .001) in patients who showed healing on postoperative magnetic resonance imaging (n = 39). ASES, Constant, and UCLA scores were significantly better in the healed group, with 100% exceeding the minimal clinically important difference for the ASES score and UCLA score and 84.2%, for Constant score. A lower proportion of patients in the retear group achieved the minimal clinically important difference. Active range of motion in all planes significantly improved for patients who had healed repairs (P < .001). Relative abduction strength, supraspinatus strength, and infraspinatus strength were at least 90% of those on the contralateral side. The recovery rate of pseudoparalysis (7 patients) was 100%. CONCLUSIONS: All-arthroscopic muscle advancement, coupled with DLLL repair, leads to a high healing rate with excellent clinical outcomes and recovery of strength to at least 90%, even in patients with pseudoparalysis. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Trustworthy deep learning framework for the detection of abnormalities in X-ray shoulder images.

Musculoskeletal conditions affect an estimated 1.7 billion people worldwide, causing intense pain and disability. These conditions lead to 30 million emergency room visits yearly, and the numbers are only increasing. However, diagnosing musculoskeletal issues can be challenging, especially in emergencies where quick decisions are necessary. Deep learning (DL) has shown promise in various medical applications. However, previous methods had poor performance and a lack of transparency in detecting shoulder abnormalities on X-ray images due to a lack of training data and better representation of features. This often resulted in overfitting, poor generalisation, and potential bias in decision-making. To address these issues, a new trustworthy DL framework has been proposed to detect shoulder abnormalities (such as fractures, deformities, and arthritis) using X-ray images. The framework consists of two parts: same-domain transfer learning (TL) to mitigate imageNet mismatch and feature fusion to reduce error rates and improve trust in the final result. Same-domain TL involves training pre-trained models on a large number of labelled X-ray images from various body parts and fine-tuning them on the target dataset of shoulder X-ray images. Feature fusion combines the extracted features with seven DL models to train several ML classifiers. The proposed framework achieved an excellent accuracy rate of 99.2%, F1Score of 99.2%, and Cohen's kappa of 98.5%. Furthermore, the accuracy of the results was validated using three visualisation tools, including gradient-based class activation heat map (Grad CAM), activation visualisation, and locally interpretable model-independent explanations (LIME). The proposed framework outperformed previous DL methods and three orthopaedic surgeons invited to classify the test set, who obtained an average accuracy of 79.1%. The proposed framework has proven effective and robust, improving generalisation and increasing trust in the final results.

Does forearm referencing using a retroversion guide achieve the targeted retroversion of the humeral component in reverse shoulder arthroplasty?

BACKGROUND: Component positioning affects clinical outcomes of reverse shoulder arthroplasty, which necessitates an implantation technique that is reproducible, consistent, and reliable. This study aims to assess the accuracy and precision of positioning the humeral component in planned retroversion using a forearm referencing guide. METHODS: Computed tomography scans of 54 patients (27 males and 27 females) who underwent primary reverse shoulder arthroplasty for osteoarthritis or cuff tear arthropathy were evaluated. A standardized surgical technique was used to place the humeral stem in 15° of retroversion. Version was assessed intraoperatively visualizing the retroversion guide from above and referencing the forearm axis. Metal subtraction techniques from postoperative computed tomography images allowed for the generation of 3D models of the humerus and for evaluation of the humeral component position. Anatomical humeral plane and implant planes were defined and the retroversion 3D angle between identified planes was recorded for each patient. Accuracy and precision were assessed. A subgroup analysis evaluated differences between male and female patients. RESULTS: The humeral retroversion angle ranged from 0.9° to 22.8°. The majority (81%) of the measurements were less than 15°. Mean retroversion angle (±SD) was 9.9° ± 5.8° (95% CI 8.4°-11.5°) with a mean percent error with respect to 15° of -34% ± 38 (95% CI -23 to -44). In the male subgroup (n = 27, range 3.8°-22.5°), the mean retroversion angle was 11.9° ± 5.4° (95% CI 9.8°-14.1°) with a mean percent error with respect to 15° of -21% ± 36 (95% CI -6 to -35). In the female subgroup (n = 27, range 0.9°-22.8°), mean retroversion angle was 8.0° ± 5.5° (95% CI 5.8°-10.1°) and the mean percent error with respect to 15° was -47% ± 36 (95% CI -32 to -61). The differences between the 2 gender groups were statistically significant (P = .006). CONCLUSION: Referencing the forearm using an extramedullary forearm referencing system to position the humeral stem in a desired retroversion is neither accurate nor precise. There is a nonnegligible tendency to achieve a lower retroversion than planned, and the error is more marked in females.

Outcomes and survivorship of anatomic total shoulder arthroplasty: current concepts.

Total shoulder arthroplasty (TSA) has been the gold standard of care for end-stage glenohumeral arthritis. Outcomes are varied and have been affected by both patient and implant characteristics. Patient factors, such as age, preoperative diagnosis, and preoperative glenoid morphology, can affect the outcomes after TSA. Similarly, the different glenoid and humeral component designs significantly affect the survivorship of TSA. Significant evolution has occurred in the design of the glenoid component with the aim of decreasing the glenoid-sided causes of failure in TSA. On the other hand, focus on the humeral component has been increasing as well, with a trend towards using shorter humeral stems. This article aims to look at the outcomes of TSA as affected by the various patient characteristics and design options for the glenoid and the humeral components. This review also aims to compare survivorship data from global literature and the Australian joint replacement registry and to provide insights into the implant combination that may provide the best patient outcome.

Single-Stage Revision Reverse Shoulder Arthroplasty: Preoperative Planning, Surgical Technique, and Mixed Reality Execution.

Revision shoulder arthroplasty is increasing with the number of primary shoulder replacements rising globally. Complex primary and revisions of shoulder arthroplasties pose specific challenges for the surgeon, which must be addressed preoperatively and intraoperatively. This article aimed to present strategies for the management of revision of shoulder arthroplasties through a single-stage approach. Preoperatively, patient factors, such as age, comorbidities, and bone quality, should be considered. The use of planning software can aid in accurately evaluating implants in situ and predict bony anatomy that will remain after explantation during the revision surgery. The planning from such software can then be executed with the help of mixed reality technology to allow accurate implant placement. Single-stage revision is performed in two steps (debridement as first step, implantation and reconstruction as the second step), guided by the following principles: adequate debridement while preserving key soft tissue attachments (i.e., rotator cuff, pectoralis major, latissimus dorsi, deltoid), restoration of glenoid joint line using bone grafting, restoration of humeral length, reconstruction and/or reattachment of soft tissues, and strict compliance with the postoperative antibiotic regimen. Preliminary results of single-stage revision shoulder arthroplasty show improvement in patient outcomes (mean 1 year), successful treatment of infection for those diagnosed with periprosthetic joint infection, and improved cost-benefit parameters for the healthcare system.