Background Bony Bankart lesions larger than a certain size can lead to a high redislocation rate, despite treatment with Bankart repair. Detection and measurement of glenoid bone loss play key roles in selecting the appropriate surgical therapy in patients with shoulder instability. There is controversy about which diagnostic modalities, using different measurement methods, provide the best diagnostic validity. Questions/purposes (1) What are the diagnostic accuracies of true AP radiographs, West Point (WP) view radiographs, MRI, and CT to detect glenoid bone loss? (2) Are there differences in the measurements of glenoid bone loss on MRI and CT? (3) What are the intrarater and interrater reliabilities of CT and MRI to measure glenoid bone loss? Methods Between August 2012 and February 2017, we treated 80 patients for anterior shoulder instability. Of those, we considered patients with available preoperative true AP radiographs, WP radiographs, CT images, and MR images of the affected shoulder as potentially eligible.

PurposeThe purpose of this study was to evaluate whether the presence of an off‐track Hill–Sachs lesion has an impact on the recurrence rate after nonoperative management of first‐time anterior shoulder dislocations. MethodsA retrospective cohort study was planned with a follow‐up via questionnaire after a minimum of 24 months. Fifty four patients were included in the study (mean age: 29.5 years; 16 female, 38 male). All of these patients opted for primary nonoperative management after first‐time traumatic anterior shoulder dislocation, in some cases even against the clinician’s advice. The glenoid track and the Hill–Sachs interval were evaluated in the MRI scans. The clinical outcome was evaluated via a shoulder‐specific questionnaire, ASES‐Score and Constant Score. Further, patients were asked to report on recurrent dislocation (yes/no), time to recurrent dislocation, pain, feeling of instability and satisfaction with nonoperative management. ResultsIn 7 (13%) patients, an off‐track Hill–Sachs lesion was present, while in 36 (67%) the lesion was on‐track and 11 (20%) did not have a structural Hill–Sachs lesion at all. In total, 31 (57%) patients suffered recurrent dislocations. In the off‐track group, all shoulders dislocated again (100%), while 21 (58%) in the on‐track group and 3 (27%) in the no structural Hill‐–Sachs lesion group had a recurrent dislocation, p = 0.008. The mean age in the group with a recurrence was 23.7 ± 10.1 years, while those patients without recurrent dislocation were 37.4 ± 13.1 years old, p < 0.01. The risk for recurrence in patients under 30 years of age was higher than in those older than 30 years (OR = 12.66, p < 0.001). There were no significant differences between patients with on‐ and off‐track lesions regarding patients’ sex, height, weight and time to reduction and glenoid diameter. Off‐track patients were younger than on‐track patients (24.9 ± 7.3 years vs. 29.6 ± 13.6 years). However, this difference was not statistically significant. ConclusionThe presence of an off‐track Hill–Sachs lesion leads to significantly higher recurrence rates compared to on‐track or no structural Hill–‐Sachs lesions in patients with nonoperative management and should be considered when choosing the right treatment option. Therefore, surgical intervention should be considered in patients with off‐track Hill–Sachs lesions. Level of evidenceIV

PurposeThe aim of the current study was to compare the diagnostic precision and reliability of different methods in measuring Hill–Sachs lesions (HSLs) using MRI and CT. MethodsA total of 80 consecutive patients with a history of anterior shoulder instability were retrospectively included. The preoperative CT and MRI scans of the affected shoulders were analysed. To investigate the ability of the Franceschi grading, Calandra classification, Richards, Hall, and Rowe grading scale, Flatow percentage and “glenoid track” assessment according to Di Giacomo et al. to quantify the extent of humeral bone loss, the results of each measurement method obtained with MRI were compared with those achieved with CT. In addition, the intra‐ and inter‐rater reliabilities of each measurement method using CT and MRI were calculated and compared. ResultsA significant difference was found between CT and MRI in the determination of the Hill–Sachs interval (HSI) (p = 0.016), but not between the results of any of the other measurement techniques. With the exceptions of the Franceschi grade and Calandra classification, all measurement methods showed good or excellent intra‐ and inter‐rater reliabilities for both MRI and CT. ConclusionsWhile the determination of the HSI with MRI was more accurate, all other analysed techniques for measuring the amount of humeral bone loss showed similar diagnostic precision. With regard to the intra‐ and inter‐rater reliabilities, all measurement techniques analysed, with the exception of the Franceschi and Calandra classifications, provided good to very good reliabilities with both CT and MRI. Level of evidenceIII

BackgroundRetearing of the supraspinatus (SSP) tendon after repair is relatively common, but its cause is rarely clear. Although the role of acromion morphology and glenoid orientation in the pathogenesis of primary SSP tendon tears have frequently been analyzed, their association with the risk of rerupture of a repaired SSP tendon is poorly understood.Questions/purposes(1) Is acromial morphology associated with the risk of retear after SSP tendon repair? (2) Is there an association between inclination and version of the glenoid and the odds for retear of the SSP tendon after repair? (3) Are there differences in outcome scores between patients who had intact cuff repairs and those who had retears?MethodsBetween August 2012 and December 2015, we treated 92 patients for SSP tendon tears; all of these patients were considered for inclusion in the present study. We considered patients with complete tear of the SSP that was reconstructed with a double-row repair and a minimum follow-up of 2 years as potentially eligible. Based on these criteria, 28% (26 of 92) were excluded because they had a partial rupture and did not receive a double-row reconstruction. A further 9% (eight of 92) were excluded because of missing planes or slices (such as sagittal, axial, or frontal) on MRI, and another 3% (three of 92) were lost before the minimum study follow-up interval or had incomplete datasets, leaving 60% (55 of 92) for inclusion in the present analysis. All included patients had a minimum follow-up of 2 years; follow-up with MRI occurred at a mean duration of 2.3 ± 0.4 years postoperatively. All patients were asked to complete the Western Ontario Rotator Cuff Index and Oxford Shoulder Scores, and they underwent MRI of the operated-on shoulder. Preoperative true AP radiographs and MR images of the affected shoulders were retrospectively assessed by measuring the acromiohumeral interval, critical shoulder angle, acromial slope, acromial tilt, acromial index, lateral acromial angle, and glenoid version and inclination. The patients also underwent acromioplasty, in which the underface of the acromion was flattened. To rule out any change in the above parameters because of acromioplasty, these parameters were compared using preoperative and postoperative MR images and showed no difference. In addition, the tendon integrity and quality on postoperative MRI were analyzed independently of one another by the same two observers using the Sugaya and Castricini classifications, accounting for atrophy and fatty degeneration of the SSP muscle. To assess interobserver reliability, the two observers took measurements independently from each other. They were orthopaedic residents who completed a training session before taking the measurements. All measurements had excellent intrarater (Cronbach alpha 0.996 [95% confidence interval (CI) 0.99 to 1.00; p > 0.01) and interrater (interrater correlation coefficient 0.975 [95% CI 0.97 to 0.98]; p > 0.01) reliabilities. To answer the study’s first question, SSP integrity on postoperative MRI ...