Comparing postoperative proprioception of the glenohumeral joint between the open and the arthroscopic Latarjet procedure.

BACKGROUND: Shoulder proprioception, in which the anterior glenohumeral capsule plays a major role, is critical to the functioning of the shoulder. Consequently, most surgeons either do not resect or reinsert the anterior capsule in shoulder stabilization surgery. In the original open Latarjet procedure (OLP), the anterior capsule is preserved. However, in the all-arthroscopic Latarjet procedure (ALP), complete anterior capsule resection is recommended for better view and access to the coracoid. This raises the question if there is a postoperative difference in proprioception between these 2 procedures. Therefore, the aims of this study are (1) to assess the difference in postoperative proprioception between the operated and healthy sides after the OLP and ALP and (2) to compare the difference in postoperative proprioception on the operated side between the OLP and ALP. METHODS: We conducted a retrospective analysis including all patients who underwent a proprioception test after an OLP or ALP at our center. Collected baseline characteristics included sex, age at surgery, operated side, hand dominance, presence of a Hill-Sachs lesion, and time between surgery and the proprioception test. For the test, patients were positioned 1 meter from a wall. They were blindfolded and had to point at a target with a laser pointer taped to their index finger. The laser point was marked and the errors were measured horizontally and vertically and categorized as <4 cm, 4-8 cm, 8-16 cm, and >16 cm. RESULTS: Between April 2022 and April 2024, a total of 91 cases were identified, of which 24 underwent an OLP and 67 underwent an ALP. No significant difference was found in error distribution between the healthy and operated side after both the OLP (P = .30 horizontally, P = .67 vertically) and ALP (P = .20 horizontally, P = .34 vertically). Moreover, there was no significant difference in error distribution between the operated sides after the OLP vs. ALP (P = .52 horizontally; P = .61 vertically). CONCLUSION: Our data suggest that postoperative proprioception is not significantly different between the operated and healthy sides after both the OLP and ALP, nor between the operated sides after the OLP vs. after the ALP. This might imply that completely resecting the anterior glenohumeral capsule does not have a detrimental effect on shoulder proprioception. However, these results are multifactorial and prospective studies are needed to better understand the regeneration potential of glenohumeral capsule mechanoreceptors and the importance of the anterior capsule for shoulder proprioception.

All-Endoscopic Treatment of Acute Acromioclavicular Joint Dislocation: Coracoclavicular Double Cerclage EndoButton Technique and Acromioclavicular Stabilization Using the Coracoacromial Ligament.

High-grade the acromioclavicular joint (ACJ) dislocations can be treated surgically. Endoscopic techniques to stabilize the ACJ using an EndoButton suture technique for coracoclavicular (CC) fixation have been shown to be safe and reproducible. Several studies have demonstrated the benefit of stabilizing the ACJ to reduce postoperative horizontal instability. This Technical Note presents a full-endoscopic technique for acute ACJ dislocations using a double-stranded EndoButton cerclage technique for CC reconstruction and an additional coracoacromial ligament transfer for acromioclavicular reconstruction. An autologous coracoacromial ligament transfer to the lateral clavicle increases stability in the horizontal plane and reduces the risk of anteroposterior recurrent instability. Clinical studies need to show whether additive ACJ fixation in addition to the all-endoscopic double cerclage EndoButton CC stabilization technique is in fact beneficial.

Methodology and development of a machine learning probability calculator: Data heterogeneity limits ability to predict recurrence after arthroscopic Bankart repair.

PURPOSE: The aim of this study was to develop and train a machine learning (ML) algorithm to create a clinical decision support tool (i.e., ML-driven probability calculator) to be used in clinical practice to estimate recurrence rates following an arthroscopic Bankart repair (ABR). METHODS: Data from 14 previously published studies were collected. Inclusion criteria were (1) patients treated with ABR without remplissage for traumatic anterior shoulder instability and (2) a minimum of 2 years follow-up. Risk factors associated with recurrence were identified using bivariate logistic regression analysis. Subsequently, four ML algorithms were developed and internally validated. The predictive performance was assessed using discrimination, calibration and the Brier score. RESULTS: In total, 5591 patients underwent ABR with a recurrence rate of 15.4% (n = 862). Age <35 years, participation in contact and collision sports, bony Bankart lesions and full-thickness rotator cuff tears increased the risk of recurrence (all p < 0.05). A single shoulder dislocation (compared to multiple dislocations) lowered the risk of recurrence (p < 0.05). Due to the unavailability of certain variables in some patients, a portion of the patient data had to be excluded before pooling the data set to create the algorithm. A total of 797 patients were included providing information on risk factors associated with recurrence. The discrimination (area under the receiver operating curve) ranged between 0.54 and 0.57 for prediction of recurrence. CONCLUSION: ML was not able to predict the recurrence following ABR with the current available predictors. Despite a global coordinated effort, the heterogeneity of clinical data limited the predictive capabilities of the algorithm, emphasizing the need for standardized data collection methods in future studies. LEVEL OF EVIDENCE: Level IV, retrospective cohort study.

How to salvage the fractured coracoid during the Latarjet Procedure? An empirical approach.

The Latarjet procedure is a frequently used stabilization procedure in case of anterior shoulder instability with critical glenoid bone loss and/or off-track Hill Sachs lesions. Although uncommon, intra-operative graft fractures do occur. When confronted with this potentially challenging intra-operative complication, having a secondary solution is paramount to achieve a successful outcome. This technical note provides a treatment algorithm that may function as a useful guideline to assist surgeons that experience this potentially complex unintended event during a Latarjet procedure. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Lateralising reverse shoulder arthroplasty using bony increased offset (BIO-RSA) or increasing glenoid component diameter: comparison of clinical, radiographic and patient reported outcomes in a matched cohort.

BACKGROUND: This study aims to compare the range of motion (ROM) of reverse shoulder arthroplasty lateralised by bony increased offset (BIO-RSA) using a standard 38-mm (mm) component to regular reverse shoulder arthroplasty (RSA) lateralised by using a 42-mm glenoid component. The secondary aims are to compare patient-reported and radiographic outcomes between the two groups. MATERIALS AND METHODS: All patients with a BIO-RSA and size 38 glenosphere were retrospectively identified and matched to patients with a regular RSA and size 42 glenosphere. Matched patients were invited for a follow-up visit. ROM was assessed as well as radiographic outcomes (lateralisation, distalisation, inferior overhang, scapular notching, heterotopic bone formation, radiolucency, stress shielding, bone graft healing and viability and complications) and patient-reported outcomes (subjective shoulder value, Constant score, American Shoulder and Elbow Surgeons, activities of daily living which require internal rotation, activities of daily living which require external rotation and a visual analogue scale for pain). Outcomes were compared between the two groups. RESULTS: In total, 38 BIO-RSAs with a size 38 glenosphere were matched to 38 regular RSAs with a size 42 glenosphere. Of the 76 matched patients, 74 could be contacted and 70 (95%) were included. At the final follow-up, there were no differences between the two groups in ROM, patient-reported outcomes or radiographic outcomes (p > 0.485). CONCLUSIONS: Using a larger glenosphere is a feasible alternative to BIO-RSA for lateralising RSA, providing comparable ROM, patient-reported and radiographic results, while potentially decreasing costs, operative time and complication rates.

High Vertical and Horizontal Stability at Short-Term Follow-Up After an All-Endoscopic Double Cerclage Endobutton Technique for Acute Acromioclavicular Joint Separations.

PURPOSE: To evaluate the clinical and radiological outcomes in the treatment of acute acromioclavicular (AC) joint separations using an all-endoscopic double cerclage endobutton technique compared with an arthroscopic-assisted single-bundle endobutton technique and to analyze the complication, failure, and revision rates of both procedures. METHODS: All patients with acute Rockwood type IIIB and V AC joint separations who were operated on using an all-endoscopic double cerclage technique (2019-2022) or an arthroscopic-assisted single-bundle technique (2017-2019) were included. The follow-up period was at least 12 months. Clinical and radiographic assessment was performed at follow-up. Complications, failures, and revisions were also investigated. RESULTS: Twenty-eight patients (14 double cerclage group, 14 single-bundle group, all male) with an average age of 37 years (interquartile range [IQR], 15) were available for follow-up after 45 months (IQR, 38). The median time between trauma and surgery was 7 days (IQR, 8). Very good clinical results without significant differences were observed in both groups (Constant score, 94 [IQR, 12] vs 95 [IQR, 15], P = .427, AC joint instability score, 95 [IQR, 11] vs 87 [IQR, 22], P = .210). All patients returned to sport, with an average sports level of 95% compared with preoperative status. The single-bundle group showed significantly increased anteroposterior instability (6 vs 0, P = .006). A total of 5 complications occurred (2 vs 3), leading to 1 revision surgery in each group. CONCLUSIONS: Excellent clinical results and high vertical and horizontal stability can be achieved with the all-endoscopic double cerclage technique. Horizontal instability occurred significantly more frequently with the single-bundle technique. The prolonged operation time in the double cerclage group had no negative impact on postoperative outcomes, including complication and failure rates, and a learning curve to reduce this prolonged operative time should be considered. LEVEL OF EVIDENCE: Level III, retrospective comparative clinical series.

Reverse shoulder arthroplasty with a 155° neck-shaft angle inlay implant design without reattachment of the subscapularis tendon results in satisfactory functional internal rotation and no instability: a cohort study.

BACKGROUND: The aim of this study was to use the Activities of Daily Living which require Internal Rotation (ADLIR) questionnaire to assess the functional internal rotation in patients who had undergone reverse shoulder arthroplasty (RSA) without reattachment of the subscapularis (SSc) tendon at a minimum follow-up of 2 years. The secondary aim was to report the objective range of motion (ROM) and the rate of postoperative instability. MATERIALS AND METHODS: All consecutive primary RSA procedures without reattachment of the SSc tendon that were performed using a Delta Xtend prosthesis (an inlay system with a 155° neck-shaft angle) between January 2015 and December 2020 were identified to ensure a minimum follow-up of 2 years. Patients were contacted and requested to fill in several questionnaires, including the ADLIR and Auto-Constant scores. RESULTS: In total, 210 patients met the inclusion criteria; among those patients, 187 could be contacted and 151 completed questionnaires (response rate: 81%). The SSc tendon was fully detached without repair in all cases, and a superolateral approach was used in 130 (86%) cases. The median follow-up was 4.5 years (range: 2.0-7.6). At final follow-up, the mean ADLIR score was 88/100 (interquartile range (IQR): 81-96). The median level reached in internal rotation was the 3rd lumbar vertebra (IQR: lumbosacral region-12th thoracic vertebra). Of the 210 eligible patients, one required a revision for a dislocation within the first month after primary surgery. With regards to regression analysis with ADLIR score as the outcome, none of the factors were associated with the ADLIR score, although age and smoking approached significance (0.0677 and 0.0594, respectively). None of the explanatory variables were associated with ROM in internal rotation (p > 0.05). CONCLUSIONS: This study demonstrates that satisfactory ADLIR scores and internal rotation ROM were obtained at mid-term follow-up after RSA leaving the SSc detached. Leaving the SSc detached also did not lead to high instability rates; only one out of 210 prostheses was revised for dislocation within the first month after primary surgery.

Subacromial Balloon Spacer Does Not Reduce the Retear Rate for Massive Rotator Cuff Tears: A Comparative Study.

PURPOSE: To determine whether a subacromial spacer decreases the recurrent rotator cuff tear rate in arthroscopically managed massive rotator cuff tears (MRCTs) with 1 year of follow-up. METHODS: We selected all patients who met the following criteria: (1) an MRCT excluding Collin type A, (2) Goutallier stage equal or less than 2, and (3) complete arthroscopic repair of the MRCT. Patients were allocated into 2 groups: A (without subacromial spacer) or B (with subacromial spacer) for a prospective evaluation 1 year after surgery. The primary outcome was the retear rate, determined with magnetic resonance imaging (MRI) according to the classification of Sugaya. Secondary outcome measures were the functional outcomes using visual analog score, Shoulder Subjective Value, and Constant-Murley Score. Preoperative rotator cuff characteristics such as number of tendons involved and the tear retraction also were evaluated. Patient-related data such as sex, age, laterality, history of smoking, and diabetes mellitus were analyzed. RESULTS: In total, 31 patients were included in group A and 33 in group B. Preoperatively, only 2 differences were found between both groups: a significant (but not clinical) greater Constant score in group A (P = .034) and a slightly greater retraction of the supraspinatus in group B (P = .0025). The overall retear rate between the 2 groups was similar regarding the number of patients (P = .746) and the total number of tendons involved in the recurrent tear (P = .112). At 1-year follow-up, no differences were found in VAS (P = .397), SSV (P = .309), and Constant score (P = .105). CONCLUSIONS: In reparable massive rotator cuff tears (excluding Collin type A), the augmentation of repair with a subacromial spacer did not significantly reduce the number of patients with recurrent rotator cuff tears identified by MRI. It was also ineffective in reducing the number of re-ruptured tendons in these patients. No patient-reported or clinically significant findings were noted in Constant, SSV, and VAS scores at 1-year postoperative follow-up. Patients with MRI findings of a healed rotator cuff (Sugaya 1-3) had better clinical outcomes compared with those without. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Functional and radiographic outcomes of reverse shoulder arthroplasty with a minimum follow-up of 10 years.

BACKGROUND: The use of reverse shoulder arthroplasty (RSA) is becoming increasingly prevalent. However, few studies have been published reporting the long-term outcomes of RSA. This study aims to report the clinical, radiographic, and patient-reported outcomes of the Delta Xtend reverse shoulder prosthesis, performed by a single surgeon and with a minimum follow-up of 10 years. METHODS: All RSA procedures performed between 2005 and 2012 were identified. Patients were contacted and invited for a follow-up visit including clinical assessment, radiographs, and patient-reported outcome measures. Patients with a follow-up of less than 10 years were excluded. The revision-free implant survival was calculated at 10 years. Between 2005 and 2012, 119 procedures in 116 patients meeting inclusion criteria were identified. Of these patients, 35 were deceased before reaching the 10-year follow-up and 23 could not be reached. In total, 63 RSAs could be included in 61 patients (response rate: 75%). The median follow-up was 11.7 years (interquartile range [IQR]: 10.5-13.2). RESULTS: Of the 61 patients, 7 patients underwent a revision after a median of 3 years (IQR: 0.2-9.8) during the total follow-up period. The 10-year implant survival was 94% (95% confidence interval: 84-98). At final follow-up, the median anterior elevation was 135° (IQR: 130°-160°), the median abduction was 120° (IQR: 100°-135°), and the median level reached with internal rotation was L5 (IQR: sacrum-L5). The median Auto-Constant score was 68 (IQR: 53-78), the median Subjective Shoulder Value was 80 (IQR: 70-93), and the median pain score was 0.2/10 (IQR: 0-2). In total, radiographs could be obtained in 25 patients (40%). Scapular notching occurred in 10 patients (40%), which was classified as Sirveaux-Nerot grade IV in 3 patients (12%). Ossification occurred in 10 patients (40%), and stress shielding in 2 patients (8%). Radiolucencies were observed around the humeral component in 24 patients (96%) and around the glenoid component in 13 patients (52%). CONCLUSION: The long-term results of RSA with a Delta Xtend prosthesis are favorable, with long-term improvement in range of motion and patient-reported outcome measures, and a satisfactory implant survival rate. Interestingly, the radiographical analysis showed high prevalence of signs associated with loosening, which did not seem to translate to high complication rates or inferior results.

Developing a machine learning algorithm to predict the probability of aseptic loosening of the glenoid component after anatomical total shoulder arthroplasty: protocol for a retrospective, multicentre study.

INTRODUCTION: Despite technological advancements in recent years, glenoid component loosening remains a common complication after anatomical total shoulder arthroplasty (ATSA) and is one of the main causes of revision surgery. Increasing emphasis is placed on the prevention of glenoid component failure. Previous studies have successfully predicted range of motion, patient-reported outcomes and short-term complications after ATSA using machine learning methods, but an accurate predictive model for (glenoid component) revision is currently lacking. This study aims to use a large international database to accurately predict aseptic loosening of the glenoid component after ATSA using machine learning algorithms. METHODS AND ANALYSIS: For this multicentre, retrospective study, individual patient data will be compiled from previously published studies reporting revision of ATSA. A systematic literature search will be performed in Medline (PubMed) identifying all studies reporting outcomes of ATSA. Authors will be contacted and invited to participate in the Machine Learning Consortium by sharing their anonymised databases. All databases reporting revisions after ATSA will be included, and individual patients with a follow-up less than 2 years or a fracture as the indication for ATSA will be excluded. First, features (predictive variables) will be identified using a random forest feature selection. The resulting features from the compiled database will be used to train various machine learning algorithms (stochastic gradient boosting, random forest, support vector machine, neural network and elastic-net penalised logistic regression). The developed and validated algorithms will be evaluated across discrimination (c-statistic), calibration, the Brier score and the decision curve analysis. The best-performing algorithm will be used to create an open-access online prediction tool. ETHICS AND DISSEMINATION: Data will be collected adhering to the WHO regulation on data sharing. An Institutional Review Board review is not applicable. The study results will be published in a peer-reviewed journal.

Biomodulating healing after arthroscopic rotator cuff repair: the protocol of a randomised proof of concept trial (BIOHACK).

PURPOSE/INTRODUCTION: Over the last decades, there has been increasing interest in biological stimulation or bioaugmentation after rotator cuff repair. So far, there is no consensus on the appropriate composition of biologicals or which patients would benefit most, and moreover, these biologicals are often expensive. However, there are other, non-pharmacological strategies that are also believed to achieve biological stimulation. This randomised controlled trial evaluates the possible cumulative effect of pragmatic application of cryobiomodulation, photobiomodulation and electrobiomodulation-collectively called biomodulation-on the bone-to-tendon healing process after rotator cuff repair. METHODS: In this randomised, controlled proof of concept study, 146 patients undergoing arthroscopic repair of a full thickness posterosuperior or anterosuperior rotator cuff tear will be 1:1 randomly assigned to either a control group or to the additional biomodulation protocol group. The adjuvant biomodulation protocol consists of seven self-applicable therapies and will be administered during the first 6 weeks after surgery. Primary outcome will be healing of the rotator cuff as evaluated by the Sugaya classification on MRI at 1-year postoperatively. ETHICS AND DISSEMINATION: This study has been accepted by the National Ethical Review Board CPP Sud-Est IV in France and has been registered at Clinicaltrials.gov. The results of this study will be published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT04618484.

The O'Brien test demonstrates a higher diagnostic value in identifying posteroinferior labral tears than superior labral anterior to posterior (SLAP) tears.

Background: The primary aim was to determine the diagnostic value of the O'Brien test in localizing labral tears of the shoulder. Methods: A consecutive series of patients electing for labral repair between January 2005 and March 2021 were included in this retrospective study. Inclusion criteria were as follows: (1) any patient with a labral tear who was elected for arthroscopic labral repair and (2) had documentation of the O'Brien test in the preoperative evaluation. Exclusion criteria were patients that had a negative arthrographically enhanced computed tomography or magnetic resonance imaging scan. During arthroscopy, the localization and extension of the labral tear was documented in a standardized 12-o'clock configuration. Anteroinferior, posteroinferior, superior labrum anterior to posterior (SLAP), and combined labral tears were documented. The sensitivity, specificity, positive and negative predictive values, accuracy, positive and negative likelihood ratios, receiver operating characteristic curve, and area under the curve were calculated to determine the diagnostic value. Results: The cohort consisted of 271 patients (77% male) and included 105 anteroinferior, 86 posteroinferior, 46 SLAP, and 32 combined parts of the labrum. The mean age at time of surgery was 30 (±10.2) years. The O'Brien test was positive in 142 (52%) patients and showed the highest sensitivity and specificity for the posteroinferior tears (83% and 62%) compared to the anteroinferior (16% and 25%), combined labral parts (69% and 50%), and SLAP (65% and 50%) tears. In addition, receiver operating characteristic-analysis demonstrated a significantly higher area under the curve for posteroinferior tears compared to the other tears (P < .001). Conclusion: The O'Brien test demonstrates more diagnostic value for posteroinferior tears than other labral tears. This includes the SLAP tear, for which the O'Brien test was originally designed. Clinical Relevance: These findings are helpful towards reinterpreting the O'Brien test as well as diagnosing, and more specifically localizing labral tears in clinics.

Developing a machine learning algorithm to predict probability of retear and functional outcomes in patients undergoing rotator cuff repair surgery: protocol for a retrospective, multicentre study.

INTRODUCTION: The effectiveness of rotator cuff tear repair surgery is influenced by multiple patient-related, pathology-centred and technical factors, which is thought to contribute to the reported retear rates between 17% and 94%. Adequate patient selection is thought to be essential in reaching satisfactory results. However, no clear consensus has been reached on which factors are most predictive of successful surgery. A clinical decision tool that encompassed all aspects is still to be made. Artificial intelligence (AI) and machine learning algorithms use complex self-learning models that can be used to make patient-specific decision-making tools. The aim of this study is to develop and train an algorithm that can be used as an online available clinical prediction tool, to predict the risk of retear in patients undergoing rotator cuff repair. METHODS AND ANALYSIS: This is a retrospective, multicentre, cohort study using pooled individual patient data from multiple studies of patients who have undergone rotator cuff repair and were evaluated by advanced imaging for healing at a minimum of 6 months after surgery. This study consists of two parts. Part one: collecting all potential factors that might influence retear risks from retrospective multicentre data, aiming to include more than 1000 patients worldwide. Part two: combining all influencing factors into a model that can clinically be used as a prediction tool using machine learning. ETHICS AND DISSEMINATION: For safe multicentre data exchange and analysis, our Machine Learning Consortium adheres to the WHO regulation 'Policy on Use and Sharing of Data Collected by WHO in Member States Outside the Context of Public Health Emergencies'. The study results will be disseminated through publication in a peer-reviewed journal. Institutional Review Board approval does not apply to the current study protocol.

Predictive value of Gagey's hyperabduction test in identifying inferior glenohumeral ligament lesions.

INTRODUCTION: Clinical tests that can identify inferior glenohumeral ligament (IGHL) complex injuries are indispensable for the diagnosis of shoulder instability. Gagey's hyperabduction test had been developed to diagnose IGHL hyperlaxity, however, it is unclear whether the test is able to accurately diagnose an IGHL lesion. The aim of this study was to (1) determine the diagnostic performance of the Gagey test in identifying an IGHL lesion and (2) determine if a positive Gagey test is more predictive for an anterior or posterior IGHL lesion thanks to the heatmapping of the lesions. It was hypothesized that a Gagey test can accurately predict IGHL lesions, but would not be able to distinguish between anterior and inferior IGHL lesions. METHODS: A retrospective diagnostic accuracy study was conducted including all consecutive patients who underwent glenoid labral repair between January 2005 and September 2021 with a documented Gagey test prior to surgery. Using arthroscopic findings as a reference standard, the diagnostic performance characteristics of the Gagey test for each type of IGHL lesion (anterior, posterior and combined) were calculated and labral heatmapping was used to depict its localisation. RESULTS: A total of 167 patients were included, with a mean age of 29±10 years. The sensitivity, specificity and accuracy of the Gagey test on determining an IGHL lesion were 46%, 38% and 46%, respectively. The positive and negative predictive values were 88% and 7%, respectively. Heatmapping of the labral lesions demonstrated that a positive Gagey test was most predictive of anterior IGHL and axillary pouch tears and non-predictive of posterior IGHL lesions. DISCUSSION: The Gagey test demonstrated a low sensitivity and specificity to identify an IGHL lesion and therefore the hypothesis could not be confirmed. However, the Gagey test has a high positive predictive value to diagnose anterior IGHL lesions. Further prospective research with a more evenly distribution of lesions is needed to investigate the clinical value of the Gagey test to identify these lesions. Based on this data, the Gagey test seems especially important to support the results of other clinical tests such as the apprehension, relocation and surprise tests. LEVEL OF EVIDENCE: III, Retrospective Case-Control study.

Correlation between preoperative clinical examination and intraoperatively found subscapularis tendon tear.

PURPOSE: Analyze the diagnostic value for subscapularis (SSC) tendon tears, their correlation between pain and strength on clinical tests, and compare them with intraoperative arthroscopic findings to prove their diagnostic value. METHODS: 110 consecutive patients undergoing arthroscopic rotator cuff repair were reviewed and allocated to isolated SSC (n = 39) and combined anterosuperior tendon tear (n = 71) groups and analyzed. Preoperative clinical testing included belly press (BPT), bear hug (BHT), lift-off (LOT), palm-up (PUT), and Jobe test (JT). All tests were performed in two categories: pain (in 4 categories: 0, 5, 10, and 15) and strength (from 0 to 5). The tendon tears were intraoperatively reviewed and classified. RESULTS: Mean age was 59 years (SD 10). The sensitivity of the BHT was 88.2% and 74.5% for BPT, while specificity was only 41.9% for BHT and 45% for BPT. Sensitivity of JT was 90.5% and 87.5% for PUT, while specificity was only 41% for JT and 28.2% for PUT. A low positive correlation for an intraoperative SSC lesion and the strength of BPT (Spearman rank correlation - 0.425; p value < 0.0001) and the strength of BHT ( - 0.362; p value = 0.001) could be found. With linear regression analysis estimated by ordinary least squares, a correlation between BPT strength and surgical grade of SSC lesion (- 0.528; 95% CI, - 0.923 to - 0.133; pvalue < 0.01) was found. CONCLUSION: The BHT showed a higher sensitivity for a SSC lesion, while the BPT had a higher correlation between preoperative testing, most notably internal rotation strength, and intraoperative surgical grade of the SSC tendon lesion. LEVEL OF EVIDENCE: Level II, Prospective cohort study for Diagnostic tests.

A pilot-study focusing on internal rotation after reverse total shoulder arthroplasty using the Activities of Daily Living which require Internal Rotation (ADLIR) score.

Background: Loss of internal rotation remains an issue after reverse total shoulder arthroplasty (RTSA). Our goal is to define the expected functional internal rotation after RTSA using the Activities of Daily Living which require Internal Rotation (ADLIR) score in a homogenous population of patients treated with RTSA. Methods: 35 patients with a minimum follow-up of two years after RTSA were evaluated using the ADLIR and Constant-Murley questionnaires. A correlation between the ADLIR and Constant score was investigated and the internal validity of the ADLIR score used in a RTSA patient population was measured using Cronbach's alpha coefficient. The impact of internal rotation on the total rotational arc of motion was defined. Results: Excellent results were recorded for both the Constant score (79 ± 18) and ADLIR score (88 ± 16). Pearson's correlation coefficient was r = 0,84 (p-value <0,001). The ADLIR score showed a high reliability for all questions. Conclusions: The ADLIR score has proven to be a useful addition in the post-operative evaluation of patients treated with RTSA. Further studies are needed to investigate the evolution of the ADLIR score from pre- to postoperatively in order to determine the clinical and predictive value of this score. Level of evidence: Level IV - Observational study.

Development and training of a machine learning algorithm to identify patients at risk for recurrence following an arthroscopic Bankart repair (CLEARER): protocol for a retrospective, multicentre, cohort study.

INTRODUCTION: Shoulder instability is a common injury, with a reported incidence of 23.9 per 100 000 person-years. There is still an ongoing debate on the most effective treatment strategy. Non-operative treatment has recurrence rates of up to 60%, whereas operative treatments such as the Bankart repair and bone block procedures show lower recurrence rates (16% and 2%, respectively) but higher complication rates (<2% and up to 30%, respectively). Methods to determine risk of recurrence have been developed; however, patient-specific decision-making tools are still lacking. Artificial intelligence and machine learning algorithms use self-learning complex models that can be used to make patient-specific decision-making tools. The aim of the current study is to develop and train a machine learning algorithm to create a prediction model to be used in clinical practice-as an online prediction tool-to estimate recurrence rates following a Bankart repair. METHODS AND ANALYSIS: This is a multicentre retrospective cohort study. Patients with traumatic anterior shoulder dislocations that were treated with an arthroscopic Bankart repair without remplissage will be included. This study includes two parts. Part 1, collecting all potential factors influencing the recurrence rate following an arthroscopic Bankart repair in patients using multicentre data, aiming to include data from >1000 patients worldwide. Part 2, the multicentre data will be re-evaluated (and where applicable complemented) using machine learning algorithms to predict outcomes. Recurrence will be the primary outcome measure. ETHICS AND DISSEMINATION: For safe multicentre data exchange and analysis, our Machine Learning Consortium adhered to the WHO regulation 'Policy on Use and Sharing of Data Collected by WHO in Member States Outside the Context of Public Health Emergencies'. The study results will be disseminated through publication in a peer-reviewed journal. No Institutional Review Board is required for this study.

Arthroscopic Bone Block Procedure for Posterior Shoulder Instability: Updated Surgical Technique.

Posterior shoulder instability is generally caused by traumatic posterior dislocations or repetitive microtrauma during sports or other activities and has an annual incidence rate of 4.64 per 100,000 person-years. Several surgical techniques to treat posterior shoulder instability have been described, including soft-tissue repair and both open and arthroscopic bone block procedures. However, even though patient-reported outcomes are commonly high, surgical procedures are associated with high complication and revision rates of up to 14% and 67%, respectively. In particular, accurate placement of the bone graft, screw orientation, and the treatment of concomitant lesions are considered challenging. Therefore, improvement of surgical techniques is desirable. This Technical Note describes an updated approach to the arthroscopic posterior bone block augmentation described by Lafosse et al. (2012), with tips and tricks on the harvest and positioning of the graft.

Technical Guide and Tips to Posterior Arthroscopic Latissimus Dorsi Transfer for Irreparable Posterosuperior Rotator Cuff Tears.

Latissimus dorsi (LD) transfer is a reliable treatment option for irreparable posterosuperior (PS) rotator cuff tears in young and active patients that need to recover the range of motion for their daily living activities. The technique starts with an arthroscopic assessment of the tear. The next step is the mini-open stage for muscle release from the subcutaneous layer of the skin, the teres major (TM), the triceps, and the lateral border and inferior angle of the scapula. Later, the scope is used to prepare the footprint (arthroscopy) and for the release and the harvest of the tendon (endoscopy), taking care not to detach the TM and not to damage the radial nerve. A grasper is used to push the LD to its correct path medial to the triceps. After that the same instrument is placed from the anterolateral and the anterior arthroscopic portals toward the mini-open incision to catch the sutures previously loaded on the LD tendon with Krackow stitches. The LD is transferred to the greater tuberosity and is attached with one medial and one lateral knotless anchors. A third point of fixation enables a partial RC repair and ensures a surface of bone to tendon healing.

The 360 Double Lasso Loop for Biceps Tenodesis: Tips and Tricks.

The management of the intra-articular portion of the long head of the biceps tendon (LHB) is a recurring topic in every discussion about shoulder pain. In massive rotator cuff tears or in tears of the superior third of the subscapularis tendon, our approach is to systematically perform a tenodesis of the LHB. In this Technical Note, we present our arthroscopic technique for LHB tenodesis at the articular margin of the humeral head using a single anchor and a 360 double lasso loop. This technique guaranties a strong and efficient fixation of the biceps tendon and is reproducible when following the steps and tips and tricks outlined herein.