Efficacy and safety of the Latarjet procedure for the treatment of athletes with glenoid bone defects ≥ 20%: a single-arm meta-analysis.

BACKGROUND: The shoulder joint is the most commonly dislocated joint in the human body, and the recurrence rate exceeds 50% after nonsurgical treatment. Although surgical treatment reduces the recurrence rate, there is controversy regarding the optimal surgical approach. Previous studies suggest that the Latarjet procedure yields favourable outcomes for specific populations at risk of recurrence, such as competitive athletes with significant glenoid defects. However, most of the existing related research consists of nonrandomized controlled trials with small sample sizes, and there is a lack of strong evidence regarding the efficacy and safety of the Latarjet procedure. METHODS: The PubMed, Embase, Cochrane Library, and Web of Science databases were systematically searched. Athletes with ≥ 20% glenoid defects were selected for inclusion. The following data were extracted: general patient information, instability rates, return to sports (RTS) rates, imaging features (graft positioning rate and graft healing rate), functional assessments [Rowe score, Athletic Shoulder Outcome Scoring System(ASOSS), visual analogue scale (VAS), forward flexion function, and external rotation function], and complications. RESULTS: After excluding suspected duplicate cases, a total of 5 studies were included in this meta-analysis. The studies involved a total of 255 patients, including 237 males (93%) and 18 females (7%). The average age at the time of surgery was 25.4 ± 8.5 years. All the studies had a minimum follow-up period of 2 years, with an average follow-up time of 48.7 ± 18.9 months. The pooled rate of return to sport (RTS) was 94.3% (95% CI: 87.3%, 98.8%), and 86.1% (95% CI: 78.2%, 92.5%) of patients returned to their preoperative level of activity. The pooled redislocation rate was 1.1% (95% CI: 0%, 3.8%). Regarding the imaging results, the combined graft retention rate was 92.1% (95% CI: 88.1%, 95.5%), and the graft healing rate was 92.1% (95% CI: 88%, 95.4%). Postoperative functional evaluation revealed that the combined Rowe score, ASOSS score, and VAS score were 93.7 ± 6.5 points, 88.5 ± 4.4 points, and 1.1 ± 10 points, respectively. The forward flexion and external rotation angles were 170.9 ± 6.9 degrees and 65.6 ± 4.5 degrees, respectively. After excluding one study with unclear complications, the combined complication rate was 9.4% (95% CI: 1.0%, 23.6%). CONCLUSION: For athletes with shoulder instability and a total of ≥ 20% glenoid bone defects, the Latarjet procedure can achieve excellent functional outcomes, with the majority of patients returning to preoperative levels of sports activity. This procedure also leads to a low recurrence rate. Therefore, the Latarjet procedure has been proven to be a safe and effective treatment.

Reconstruction of recurrent shoulder dislocation with glenoid bone defect with 3D-printed titanium alloy pad: outcomes at 2-year minimum follow-up.

BACKGROUND: To evaluate the outcome of shoulder arthroscopy-assisted implantation of three-dimensional (3D)-printed titanium pads for recurrent shoulder dislocation with glenoid bone defects. METHODS: From June 2019 to May 2020, the clinical efficacy of 3D printed titanium pad implantation assisted by shoulder arthroscopy, for the treatment of recurrent shoulder dislocations with shoulder glenoid defects was retrospectively analyzed. The American Shoulder and Elbow Surgeons (ASES) shoulder, Rowe, and Constant scores were recorded before surgery and at 3 months, 6 months, 1 year, and 2 years after surgery. 3D computed tomography (CT) and magnetic resonance imaging were used to evaluate the location of the glenoid pad, bone ingrowth, joint degeneration, and osteochondral damage. RESULTS: The mean age of the 12 patients was 21.4 (19-24) years and the mean follow-up time was 27.6 (24-35) months. The Visual Analog Scale score significantly improved from 5.67 ± 1.98 preoperatively to 0.83 ± 0.58 postoperatively (p = 0.012). The postoperative ASES score was significantly increased to 87.91 ± 3.47 compared with preoperative ASES score (46.79 ± 6.45) (p < 0.01). Rowe and Constant scores also improved from 22.5 ± 12.34 and 56.58 ± 7.59 preoperatively to 90.83 ± 4.69 and 90.17 ± 1.89 at 2 years postoperatively, respectively. CT performed 2 years after surgery showed that the pad perfectly replenished the bone-defective part of the shoulder glenoid and restored the articular surface curvature of the shoulder glenoid in the anterior-posterior direction, and the bone around the central riser of the pad was tightly united. Magnetic resonance imaging 2 years after surgery showed that the humeral head osteochondral bone was intact, and there was no obvious osteochondral damage. CONCLUSIONS: 3D printed titanium pads are a reliable, safe, and effective surgical procedure for treating recurrent shoulder dislocations with glenoid bone defects.

Defining Critical Humeral Bone Loss: Inferior Craniocaudal Hill-Sachs Extension as Predictor of Recurrent Instability After Primary Arthroscopic Bankart Repair.

BACKGROUND: The glenoid track concept for shoulder instability primarily describes the medial-lateral relationship between a Hill-Sachs lesion and the glenoid. However, the Hill-Sachs position in the craniocaudal dimension has not been thoroughly studied. HYPOTHESIS: Hill-Sachs lesions with greater inferior extension are associated with increased risk of recurrent instability after primary arthroscopic Bankart repair. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: The authors performed a retrospective analysis of patients with on-track Hill-Sachs lesions who underwent primary arthroscopic Bankart repair (without remplissage) between 2007 and 2019 and had a minimum 2-year follow-up. Recurrent instability was defined as recurrent dislocation or subluxation after the index procedure. The craniocaudal position of the Hill-Sachs lesion was measured against the midhumeral axis on sagittal magnetic resonance imaging (MRI) using either a Hill-Sachs bisecting line through the humeral head center (sagittal midpoint angle [SMA], a measure of Hill-Sachs craniocaudal position) or a line tangent to the inferior Hill-Sachs edge (lower-edge angle [LEA], a measure of Hill-Sachs caudal extension). Univariate and multivariate regression were used to determine the predictive value of both SMA and LEA for recurrent instability. RESULTS: In total, 176 patients were included with a mean age of 20.6 years, mean follow-up of 5.9 years, and contact sport participation of 69.3%. Of these patients, 42 (23.9%) experienced recurrent instability (30 dislocations, 12 subluxations) at a mean time of 1.7 years after surgery. Recurrent instability was found to be significantly associated with LEA >90° (ie, Hill-Sachs lesions extending below the humeral head equator), with an OR of 3.29 (P = .022). SMA predicted recurrent instability to a lesser degree (OR, 2.22; P = .052). Post hoc evaluation demonstrated that LEA >90° predicted recurrent dislocations (subset of recurrent instability) with an OR of 4.80 (P = .003). LEA and SMA were found to be collinear with Hill-Sachs interval and distance to dislocation, suggesting that greater LEA and SMA proportionally reflect lesion severity in both the craniocaudal and medial-lateral dimensions. CONCLUSION: Inferior extension of an otherwise on-track Hill-Sachs lesion is a highly predictive risk factor for recurrent instability after primary arthroscopic Bankart repair. Evaluation of Hill-Sachs extension below the humeral equator (inferior equatorial extension) on sagittal MRI is a clinically facile screening tool for higher-risk lesions with subcritical glenoid bone loss. This threshold for critical humeral bone loss may inform surgical stratification for procedures such as remplissage or other approaches for at-risk on-track lesions.

Latarjet in women for anterior shoulder instability: a case series analysis.

PURPOSE: The Latarjet procedure is traditionally used to treat chronic anterior shoulder instability associated with glenoid bone loss. However, few series have analyzed outcomes in a female-only population. The objective of this study was to evaluate the clinical and radiological outcomes of a Latarjet bone block in this specific population. METHODS: This single-center retrospective study included 15 women (mean age 35 ± 11.3; 19-60) reviewed with a minimum follow-up of 2 years. The procedure was performed using the open bone block screw technique (n = 7) or by arthroscopy with cortical button (n = 8). Clinical evaluation was based on active range of motion measurements, Rowe and Walch-Duplay scores, and subjective shoulder value (SSV). Radiographic analysis explored bone block healing at the last follow-up. RESULTS: At a mean follow-up of 48 months (32-86), no recurrence was reported. The mean Rowe score was 91 points (70-100), Walch-Duplay 90 points (60-100), and SSV 87% (70-100). The active mobilities reached 169° (± 9°) in elevation, 57° (± 15°) in external rotation at side, and 89° (± 6°) in abduction. The return-to-sport rate was 91%. Five patients experienced persistent anterior pain, with screws requiring hardware removal in 2 (p = 0.02). Radiological assessment detected one case of nonunion (7%). CONCLUSION: Women treated with the Latarjet procedure experienced satisfactory midterm clinical outcomes. The arthroscopic technique using cortical button fixation seems to avoid residual anterior pain requiring hardware removal.

Automated quantification of glenoid bone loss in CT scans for shoulder dislocation surgery planning.

PURPOSE: Estimation of glenoid bone loss in CT scans following shoulder dislocation is required to determine the type of surgery needed to restore shoulder stability. This paper presents a novel automatic method for the computation of glenoid bone loss in CT scans. METHODS: The model-based method is a pipeline that consists of four steps: (1) computation of an oblique plane in the CT scan that best matches the glenoid face orientation; (2) selection of the glenoid oblique CT slice; (3) computation of the circle that best fits the posteroinferior glenoid contour; (4) quantification of the glenoid bone loss. The best-fit circle is computed with newly defined Glenoid Clock Circle Constraints. RESULTS: The pipeline and each of its steps were evaluated on 51 shoulder CT scans (44 patients). Ground truth oblique slice, best-fit circle, and glenoid bone loss measurements were obtained manually from three clinicians. The full pipeline yielded a mean absolute error (%) for the bone loss deficiency of 2.3 ± 2.9 mm (4.67 ± 3.32%). The mean oblique CT slice selection difference was 1.42 ± 1.32 slices, above the observer variability of 1.74 ± 1.82 slices. The glenoid bone loss deficiency measure (%) on the ground truth oblique glenoid CT slice has a mean average error of 0.54 ± 1.03 mm (4.76 ± 3.00%), close to the observer variability of 0.93 ± 1.40 mm (2.98 ± 4.97%). CONCLUSION: Our pipeline is the first fully automatic method for the quantitative analysis of glenoid bone loss in CT scans. The computed glenoid bone loss report may assist orthopedists in selecting and planning surgical shoulder dislocation procedures.

The arthroscopic double-button Latarjet does not modify the static posterior translation of the humeral head.

INTRODUCTION: The Latarjet procedure treats anterior instability of the shoulder and is based on a triple anterior lock, where the conjoint tendon straps the lower third of the subscapularis muscle. Excessive posterior translation of the humeral head is a known risk factor for shoulder osteoarthritis. No in vivo study has investigated the effect of the bone block on the posterior static translation of the humeral epiphysis. The purpose of this study was to evaluate the effect of the bone block on the static posterior translation of the humeral head. The hypothesis was that this procedure increased this translation. MATERIALS AND METHODS: This retrospective study included patients treated arthroscopically for anterior shoulder instability by a double-button Latarjet. An independent examiner analyzed the CT scans preoperatively, at 15 days, and at least 6 months postoperatively according to a standardized protocol. The analysis focused on the position of the bone block in the axial and coronal planes relative to the glenoid. The posterior translation was automatically calculated using the Blueprint© planning software. RESULTS: Thirty-five patients were included with a mean age of 25 years (16-43), according to a 4M/1F sex ratio. The graft was perfectly flush to the subchondral bone in 63% (n=22) of cases and subequatorial in 91% (n=32). Preoperative posterior humeral translation was 52%. The mean immediate postoperative posterior humeral translation was 56%, and 57% at more than 6 months. The change in mean posterior humeral translation between preoperative/6 months was +0.94% [-20%; +12%] (p=0.29) and immediate postoperative/6 months +0.34% [-18%; +15%] (p=0.84). Gender, hypermobility and the axial position of the bone block did not influence the change in posterior humeral translation. The equatorial position of the bone block appeared to increase posterior humeral translation by +10%±5.2% [-0.427; 20.823] (p=0.07). CONCLUSION: This work refutes our initial hypothesis. The change in static posterior humeral translation after arthroscopic Latarjet bone block remains stable at more than 6 months of follow-up. This procedure does not alter the anatomical position of the humeral head in relation to the glenoid. On the other hand, a more cranial positioning of the bone block could have an influence. LEVEL OF EVIDENCE: IV.

Humeral Head Reconstruction of Reverse Hill-Sachs Lesions.

Compared with anterior instability, posterior shoulder dislocations are a rare entity and are often missed at presentation. A concomitant anteromedial impression fracture of the humeral head, or a reverse Hill-Sachs lesion, is commonly present with these dislocations and is more pronounced with a longer timeline to reduction. Treatment of these defects ranges from nonsurgical treatment to soft-tissue procedures, bony reconstruction, and arthroplasty. Management may be dictated by various factors, such as patient demands, defect size and location, concomitant injuries, and underlying etiology. Small reverse Hill-Sachs defects without engagement can generally be treated nonsurgically or with benign neglect, whereas larger defects (>20%) often require surgery. The most reported surgical techniques are the (arthroscopic) McLaughlin and modified McLaughlin procedure, disimpaction and bone grafting, or reconstruction of the defect with autograft or with fresh (or fresh-frozen) osteochondral allograft. Finally, arthroplasty is generally required for large defects, where more than 45% to 50% of the articular cartilage is involved. Overall, reported outcomes generally reflect patient satisfaction for most patients, with a low incidence of secondary instability or posttraumatic arthritis, although better results are achieved when recognizing and treating these injuries in the more acute setting.

How does dynamic arthroscopic tracking compare with radiologic glenoid track for identification of on- and off-track lesions in anterior shoulder instability?

BACKGROUND: Current treatment paradigms for anterior shoulder instability are based on radiologic measurements of glenohumeral bone defects, and mathematical calculation of the glenoid track (GT) is used to classify lesions into on-track and off-track morphology. However, radiologic measurements have shown high variability, and GT widths under dynamic conditions have been reported to be significantly smaller than those under static radiologic conditions. The purpose of this study was to assess the reliability, reproducibility, and diagnostic validity of dynamic arthroscopic standardized tracking (DAST) in comparison to the gold-standard radiologic track measurement method for the identification of on- and off-track bony lesions in patients with anteroinferior shoulder instability. METHODS: Between January 2018 and August 2022, 114 patients with traumatic anterior shoulder instability were evaluated using 3-T magnetic resonance imaging or computed tomography scans; glenoid bone loss, Hill-Sachs interval, GT, and Hill-Sachs occupancy ratio (HSO) were measured, and defects were classified as on-track or off-track defects and peripheral-track defects (based on HSO percentage) by 2 independent researchers. During arthroscopy, a standardized method (DAST method) was used by 2 independent observers to classify defects into on-track defects (central and peripheral) and off-track defects. Interobserver reliability of the DAST and radiologic methods was calculated using the κ statistic and reported as percentage agreement. Diagnostic validity (sensitivity, specificity, positive predictive value, and negative predictive value) of the DAST method was calculated using the radiologic track (HSO percentage) as the gold standard. RESULTS: The radiologically measured mean glenoid bone loss percentage, Hill-Sachs interval, and HSO in off-track lesions were lower with the arthroscopic method (DAST) as compared with the radiologic method. The DAST method showed nearly perfect agreement between the 2 observers for the on-track/off-track classification (κ = 0.96, P < .001) and the on-track central or peripheral /off-track classification (κ = 0.88, P < .001). The radiologic method showed greater interobserver variability (κ = 0.31 and κ = 0.24, respectively) with only fair agreement for both classifications. Inter-method agreement varied between 71% and 79% (95% confidence interval, 62%-86%) between the 2 observers, and reliability was assessed as slight (κ = 0.16) to fair (κ = 0.38). Overall, for identification of an off-track lesion, the DAST method showed maximum specificity (81% and 78%) when radiologic peripheral-track lesions (HSO percentage of 75%-100%) were considered off-track and showed maximum sensitivity when arthroscopic peripheral-track lesions were classified as off-track. CONCLUSION: Although inter-method agreement was low, a standardized arthroscopic tracking method (DAST method) showed superior interobserver agreement and reliability for lesion classification in comparison to the radiologic track method. Incorporating DAST into current algorithms may help reduce variability in surgical decision making.

The V angle compliments radiographic assessment of acute acromioclavicular joint dislocations by differentiating between Rockwood types III versus V and by considering dynamic horizontal translation in coronal radiographs.

PURPOSE: Acromioclavicular joint (ACJ) dislocations are usually graded radiographically according to Rockwood, but differentiation between Rockwood types III and V may be ambiguous. The potentially clinically relevant horizontal instability is barely addressed in coronal radiographs. It was hypothesized that a new radiologic parameter (V angle) would complement ACJ diagnostics on anteroposterior radiographs by differentiating between cases of Rockwood III and V while also considering the aspect of dynamic horizontal translation (DHT). METHODS: Ninety-five patients with acute ACJ dislocations (Rockwood types III and V) were included retrospectively between 2017 and 2020. On anteroposterior views (weightbearing: n = 62, non-weight-bearing: n = 33), the coracoclavicular (CC) distance and the newly introduced V angle for assessing scapular orientation were measured bilaterally. This angle is referenced between the spinal column and a line crossing the superior scapular angle and the crossing point between the supraspinatus fossa and the medial base of the coracoid process, reported as the side-comparative difference (non-injured side *minus* injured side). DHT on Alexander views was divided into stable, partially unstable or completely unstable. RESULTS: The V angle on the injured side alone (mean 50.0°; 95% confidence interval (CI), 48.6°-51.3°) showed no correlation with the side-comparative CC distance [%] (r = - 0.040; n.s.). Thus, the V angle on the non-injured side was considered, displaying a normal distribution (n.s.) with a mean of 58.0° (95% CI, 56.6°-59.4°). The side-comparative V angle showed a correlation with the side-comparative CC distance (r = 0.83; p < 0.001) and was able to differentiate between Rockwood types III (4.7°; 95% CI, 3.9°-5.5°; n = 39) and V (10.3°; 95% CI, 9.7°-11.0°; n = 56) (p < 0.001). A cut-off value of 7° had a 94.6% sensitivity and an 82.1% specificity (area under curve, AUC: 0.954; 95% CI, 0.915-0.994). The side-comparative V angle was greater for cases with complete DHT (8.7°; 95% CI, 7.9°-9.5°; n = 78) than for cases with partial DHT (4.8°; 95% CI, 3.3°-6.3°; n = 16) (p < 0.001). A cut-off value of 5° showed a sensitivity of 84.6% and a specificity of 66.7% (AUC 0.824; 95% CI, 0.725-0.924). CONCLUSION: The scapular-based V angle on anteroposterior radiographs distinguishes between Rockwood types III and V as well as cases with partial or complete DHT. STUDY DESIGN: Diagnostic study. LEVEL OF EVIDENCE: Level II.

[A study of the correlation between glenohumeral joint congruence and stability in recurrent shoulder dislocations].

Objective: To investigate the correlation between glenohumeral joint congruence and stability in recurrent shoulder dislocations. Methods: Eighty-nine patients (89 sides) with recurrent shoulder dislocation admitted between June 2022 and June 2023 and met the selection criteria were included as study subjects. There were 36 males and 53 females with an average age of 44 years (range, 20-79 years). There were 40 cases of left shoulder and 49 cases of right shoulder. The shoulder joints dislocated 2-6 times, with an average of 3 times. The three-dimensional models of the humeral head and scapular glenoid were reconstructed using Mimics 20.0 software based on CT scanning images. The glenoid track (GT), inclusion index, chimerism index, fit index, and Hill-Sachs interval (HSI) were measured, and the degree of on/off track was judged (K value, the difference between HSI and GT). Multiple linear regression was used to analyze the correlation between the degree of on/off track (K value) and inclusion index, chimerism index, and fit index. Results: Multiple linear regression analysis showed that the K value had no correlation with the inclusion index ( P>0.05), and was positively correlated with the chimerism index and the fit index ( P<0.05). Regression equation was K=-24.898+35.982×inclusion index+8.280×fit index, R 2=0.084. Conclusion: Humeral head and scapular glenoid bony area and curvature are associated with shoulder joint stability in recurrent shoulder dislocations. Increased humeral head bony area, decreased scapular glenoid bony area, increased humeral head curvature, and decreased scapular glenoid curvature are risk factors for glenohumeral joint stability.

Does glenoid bone loss accompany posterior shoulder instability with only labral tear? A magnetic resonance imaging-based study.

BACKGROUND: The primary aim of this study was to investigate bone loss in the glenoid with magnetic resonance imaging in posterior shoulder instability with only a labral tear. METHODS: A total of 76 patients operated on because of posterior and anteroposterior shoulder instability only with a labral tear between 2006 and 2019 (n = 40 and n = 36, respectively) were included in this study. The instability type, a presence of an additional superior labrum anteroposterior (SLAP) lesion, the number of dislocations, and the magnetic resonance imaging-based measurements (the glenoid diameter and the bone defect size in the glenoid, the Hill-Sachs lesion [HSL] and the reverse HSL [rHSL] length, the angle and the arc length of HSL and rHSL, and the humerus head diameter and its area) were analyzed. RESULTS: The size of the anterior glenoid defect, the rHSL measurements (length, angle, and arc length), and the ratio of the anterior glenoid defect size to the glenoid diameter were significantly higher for anteroposterior instability (P < .01) cases. There was no significant difference (P = .49, .64, and .82, respectively) for the presence of an additional SLAP pathology, the glenoid diameter, the posterior glenoid defect, and the ratio of the posterior glenoid defect size to the glenoid diameter in posterior and anteroposterior instability groups. The increased number of dislocations was associated with increased rHSL length and total arc length (P = .04 and .03, respectively). An additional SLAP lesion in posterior shoulder instabilities was not associated with the bone defect size (P = .29). CONCLUSION: Although the posterior shoulder instability with only a labral tear is likely to cause a bone defect, we have shown that the instability is not expected to be caused by the bone defect. Therefore, this study points out that only soft tissue repair without considering the bone defect could be promising in this patient group.

Lesion prevalence and patient outcome comparison between primary and recurrent anterior shoulder instability.

BACKGROUND: The purpose of this study was to compare lesion prevalence and treatment outcomes in patients with primary and recurrent anterior shoulder instability. METHODS: Patients who were admitted to the institution with a diagnosis of anterior shoulder instability and who underwent arthroscopic surgery between July 2006 and February 2020 were retrospectively evaluated. Minimum follow-up duration of the patients was 24 months. The recorded data and magnetic resonance imaging (MRI) of the patients were examined. Patients aged ≥40 years, with a history of shoulder region fracture, inflammatory arthritis, a history of epilepsy, multidirectional instability, nontraumatic dislocation, and off-track lesions were excluded from the study. Shoulder lesions were documented and patient outcome evaluation was made with the Oxford Shoulder Score (OSS) and visual analog scale (VAS). RESULTS: A total of 340 patients were included in the study. The mean age of patients was 25.6 years (±6.49). The recurrent instability group had a significantly higher rate of anterior labroligamentous periosteal sleeve avulsion (ALPSA) lesions compared to the primary instability group (40.6% vs. 24.6% respectively) (P = .033). Twenty-five patients (43.9%) had superior labrum anterior and posterior (SLAP) lesions in the primary instability group and 81 patients (28.6%) had SLAP lesions in the recurrent instability group (P = .035). OSS increased for both primary (from 35 [16-44] to 46 [36-48]) (P = .001) and recurrent instability groups (from 33 [6-45] to 47 [19-48]) (P = .001). There was no significant difference between the groups regarding postoperative VAS and OSS scores (P > .05). CONCLUSIONS: Successful results were obtained in patients younger than 40 years with both primary and recurrent anterior shoulder instability after arthroscopic treatment. ALPSA lesion prevalence was higher whereas SLAP lesion prevalence was lower in patients with recurrent instability. Although the postoperative OSS was comparable between the patient groups, the failure rate was higher in the recurrent instability patients.

Glenoid segmentation from computed tomography scans based on a 2-stage deep learning model for glenoid bone loss evaluation.

BACKGROUND: The best-fitting circle drawn by computed tomography (CT) reconstruction of the en face view of the glenoid bone to measure the bone defect is widely used in clinical application. However, there are still some limitations in practical application, which can prevent the achievement of accurate measurements. This study aimed to accurately and automatically segment the glenoid from CT scans based on a 2-stage deep learning model and to quantitatively measure the glenoid bone defect. MATERIALS AND METHODS: Patients who were referred to our institution between June 2018 and February 2022 were retrospectively reviewed. The dislocation group consisted of 237 patients with a history of ≥2 unilateral shoulder dislocations within 2 years. The control group consisted of 248 individuals with no history of shoulder dislocation, shoulder developmental deformity, or other disease that may lead to abnormal morphology of the glenoid. All patients underwent CT examination with a 1-mm slice thickness and a 1-mm increment, including complete imaging of the bilateral glenoid. A residual neural network (ResNet) location model and a U-Net bone segmentation model were constructed to develop an automated segmentation model for the glenoid from CT scans. The data set was randomly divided into training (201 of 248) and test (47 of 248) data sets of control-group data and training (190 of 237) and test (47 of 237) data sets of dislocation-group data. The accuracy of the stage 1 (glenoid location) model, the mean intersection-over-union value of the stage 2 (glenoid segmentation) model, and the glenoid volume error were used to assess the performance of the model. The R2 value and Lin concordance correlation coefficient were used to assess the correlation between the prediction and the gold standard. RESULTS: A total of 73,805 images were obtained after the labeling process, and each image was composed of CT images of the glenoid and its corresponding mask. The average overall accuracy of stage 1 was 99.28%; the average mean intersection-over-union value of stage 2 was 0.96. The average glenoid volume error between the predicted and true values was 9.33%. The R2 values of the predicted and true values of glenoid volume and glenoid bone loss (GBL) were 0.87 and 0.91, respectively. The Lin concordance correlation coefficient value of the predicted and true values of glenoid volume and GBL were 0.93 and 0.95, respectively. CONCLUSION: The 2-stage model in this study showed a good performance in glenoid bone segmentation from CT scans and could quantitatively measure GBL, providing a data reference for subsequent clinical treatment.

[Treatment strategies for traumatic anterior shoulder dislocation]. / Therapiestrategien bei traumatischer ventraler Schultererstluxation.

Anterior glenohumeral instability is the most frequent type of shoulder instability. This is often associated with labral and osseous lesions leading to recurrent instability. A detailed medical history, a physical examination and targeted diagnostic imaging are necessary to assess possible pathological soft tissue alterations as well as bony lesions of the humeral head and the glenoid bone. Early surgical treatment has been shown to reduce the risk of recurrence, especially in young active athletes, and can avoid secondary damage. Shoulder dislocations in older patients also require a detailed assessment and selection of treatment as persisting pain and limitation of movement can occur due to rotator cuff lesions and nerve injuries. The purpose of this article is to provide an overview of the currently available evidence and results regarding diagnostic considerations and conservative vs. surgical treatment and time to return to sport after treatment of a primary anterior shoulder dislocation.

Simultaneous acromioclavicular dislocation, proximal humeral fracture, and reverse Hill-Sachs lesion: a case report.

BACKGROUND: In cases with injuries to the shoulder region, the combination of acromioclavicular joint dislocation, reverse Hill-Sachs lesion, and proximal humeral fracture is a very rare condition. CASE PRESENTATION: This study described a 38-year-old male Persian patient with simultaneous acromioclavicular joint dislocation, proximal humeral fracture, and reverse Hill-Sachs lesion due to motor vehicle crash injury who underwent arthroscopic acromioclavicular joint fixation using tight rope technique. In the 7-month follow-up period following the surgical fixation, range of motion was approximately normal. Reduction and hardware were intact, no dislocation or apprehension to dislocation was observed. Patient only had minor shoulder pain at the end of range of motion and a dull pain on the site of incision over the clavicle in deep touch. Our findings showed acceptable arthroscopic outcomes in the management of such complex case. CONCLUSION: Our experience on this case showed acceptable outcomes of the arthroscopic treatment of the acromioclavicular joint dislocation in the management of such a complex case with associated injuries to the shoulder region.

Use of Computed Tomography in the Evaluation of Anterior Shoulder Instability: Possible Effect on Surgical Management.

BACKGROUND: Glenoid bone loss is a critical factor in the management of anterior shoulder instability (ASI). Computed tomography (CT) is often considered the gold standard to evaluate glenoid bone loss, but it is associated with negative factors such as radiation. Thus, interest exists as to when orthopaedic surgeons need a CT scan to guide decision-making when treating ASI. PURPOSE: To determine whether information gained from a shoulder CT scan alters orthopaedic surgeons' management plan for ASI and, secondarily, to determine whether surgeon- and patient-specific factors affect whether a CT scan changes treatment and which clinical factors are most important in surgical decision-making. STUDY DESIGN: Cross-sectional study. METHODS: A questionnaire composed of 24 ASI vignettes was administered to Herodicus Society members, American Shoulder and Elbow Surgeons Neer Circle members, and sports medicine fellowship-trained orthopaedic surgeons. Participants chose their recommended surgical treatment from the options of arthroscopic Bankart repair, open Bankart repair, bony reconstruction procedure, or other based on patient history, radiographs, and magnetic resonance imaging. Participants were then shown CT images and asked whether their treatment plan changed and, if not, whether the CT scan was not necessary or had reinforced their decision. Generalized linear mixed-effects logistic regression modeling was performed to assess the influence of vignette and respondent characteristics on treatment decisions. RESULTS: A total of 74 orthopaedic surgeons completed the survey; 96% were fellowship trained (sports medicine, 50%; shoulder and elbow surgery, 41%), and 66% practiced in academic settings. CT imaging did not change the selected treatment strategy in 75.6% of responses. In cases when management did not change, surgeons reported that the CT scan reinforced their decision in 53.4% of responses and was not necessary for decision-making in 22.2% of responses. Decision-making was more likely to be changed after CT in male patients and those with off-track lesions. CONCLUSION: Information gained from a CT scan did not alter treatment decision-making in three-quarters of vignettes among surgeons experienced in the management of ASI. The finding that CT scans did alter the treatment plan in nearly a quarter of cases is not insignificant, and it appears that in patients with borderline glenoid track status and few other risk factors for recurrence after arthroscopic stabilization, CT imaging is more likely to change management.

Risk factors of loss of reduction after acromioclavicular joint dislocation treated with a hook plate.

BACKGROUND: Acromioclavicular joint fixation using a hook plate is effective for the treatment of acute acromioclavicular joint dislocation. However, several studies have reported some complications including loss of reduction after surgery for acromioclavicular joint dislocation. This study aimed to identify the risk factors associated with the loss of reduction after acromioclavicular joint dislocation surgery using a hook plate. METHODS: This was a retrospective study that assessed 118 patients with acromioclavicular joint dislocation, who were diagnosed between March 2013 and January 2019 and underwent surgical treatment using the hook plate (reduction loss group: n = 38; maintenance group: n = 80). The mean follow-up period was 29.9 months (range, 24-40 months). We assessed the range of motion, the American Shoulder and Elbow Surgeons score (ASES), visual analog scale score for pain, and a subjective shoulder value. Radiological assessment of coracoid clavicular distance was performed. The risk factors of reduction loss were analyzed using multivariable logistic regression analysis. RESULTS: Age (p = 0.049), sex (female, p = 0.03, odds ratio OR = 4.81), Rockwood type V (p = 0.049, OR = 2.20), and time from injury to surgery > 7 days (p = 0.018, OR = 2.59) were statistically significant factors in the reduction loss group. There were no significant differences in the clinical outcomes for range of motion, ASES, subjective shoulder value, and visual analog scale scores between the two groups. In the radiological results, preoperative coracoid clavicular distance (p = 0.039) and ratio (p = 0.001), and over-reduction (p = 0.023, OR = 0.40) were significantly different between the two groups. The multivariate logistic regression analysis identified the female sex (p = 0.037, OR = 5.88), a time from injury to surgery > 7 days (p = 0.019, OR = 3.36), and the preoperative coracoid clavicular displacement ratio of the injured shoulder (p < 0.001, OR = 1.03) as risk factors associated with reduction loss following surgery using a hook plate for acromioclavicular dislocation. CONCLUSION: A delayed timing of surgery > 7 days, preoperative coracoid clavicular displacement ratio of the injured shoulder, and female sex were identified as risk factors for loss of reduction after surgery using a hook plate for acromioclavicular joint dislocation. LEVEL OF EVIDENCE: Level IV; retrospective comparison; treatment study.

Arthroscopic Bankart Repair for Adolescent Anterior Shoulder Instability: Clinical and Imaging Predictors of Revision Surgery and Recurrent Subjective Instability.

BACKGROUND: Multiple clinical and radiologic risk factors for recurrent instability after arthroscopic Bankart repair have been described. Humeral bone loss has gained more recent attention, particularly with respect to "off-track" lesions and increased rates of recurrent instability and revision surgery. PURPOSE: To evaluate clinical and radiologic predictors of failure after arthroscopic Bankart repair in adolescents. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A single-institution retrospective study was performed in patients <19 years of age treated with arthroscopic Bankart repair from 2011 to 2017. Magnetic resonance imaging measurements of glenoid and humeral bone loss, the glenoid track, and the presence of off-track Hill-Sachs (HS) lesions were assessed. All patients had a minimum follow-up of 24 months and completed patient-reported outcome scores. Failure was defined as revision surgery or postoperative subjective instability. RESULTS: A total of 59 patients (46 male, 13 female) with a median age of 16 years (range, 12-18 years) were included. Ten patients (17%) had revision surgery and 8 patients (14%) had subjective instability without revision surgery. No clinical or radiologic factors were significantly different between the failure cohort and the nonfailure cohort. Four patients (7%) measured off-track, and 2 of these patients experienced failure. A total of 38 patients (64%) were identified to have an HS defect. Subgroup analysis of these patients identified a greater HS interval (HSI) in patients who underwent revision surgery as compared with those patients who did not have revision surgery. Among patients with GT ratio ≥15 mm, there was a 50% rate of revision surgery. The Pediatric/Adolescent Shoulder Survey (PASS) and Single Assessment Numeric Evaluation (SANE) scores at the final follow-up were not significantly different among patients with or without revision surgery. However, those with subjective instability who had not undergone revision surgery had significantly lower PASS and SANE scores as compared with the remainder of the cohort. CONCLUSION: Of the adolescents in this cohort, 31% either had revision surgery (17%) or reported subjective feelings of instability (14%) after arthroscopic Bankart repair. Off-track instability was identified in 7% of the cohort but was not predictive of failure. Among the subgroup of patients with an HS defect, those who underwent revision surgery had a significantly larger HSI.