Radiographic shoulder parameters and their relationship to outcomes following rotator cuff repair: a systematic review

Deep learning algorithms enable MRI-based scapular morphology analysis with values comparable to CT-based assessments

Scapular morphological attributes show promise as prognostic indicators of retear following rotator cuff repair. Current evaluation techniques using single-slice magnetic-resonance imaging (MRI) are, however, prone to error, while more accurate computed tomography (CT)-based three-dimensional techniques, are limited by cost and radiation exposure. In this study we propose deep learning-based methods that enable automatic scapular morphological analysis from diagnostic MRI despite the anisotropic resolution and reduced field of view, compared to CT. A deep learning-based segmentation network was trained with paired CT derived scapula segmentations. An algorithm to fuse multi-plane segmentations was developed to generated high-resolution 3D models of the scapula on which morphological landmark- and axes were predicted using a second deep learning network for morphological analysis. Using the proposed methods, the critical shoulder angle, glenoid inclination and version were measured from MRI with accuracies of -1.3 ± 1.7 degrees, 1.3 ± 2.1 degree, and - 1.4 ± 3.4 degrees respectively, compared to CT. Inter-class correlation between MRI and CT derived metrics were substantial for the glenoid version and almost perfect for the other metrics. This study demonstrates how deep learning can overcome reduced resolution, bone border contrast and field of view, to enable 3D scapular morphology analysis on MRI.

The Acromiohumeral Center-Edge Angle and Risk of Rotator Cuff Tear: A Plain Radiograph and MRI Study

Introduction

The acromiohumeral center-edge angle (ACEA) is a parameter that can be measured on plain shoulder radiographs and has been found to be associated with increased risk of sustaining a rotator cuff tear.

Purpose

The aim of this study was to investigate this association using plain radiographs and to explore its applicability on shoulder magnetic resonance imaging (MRI) in the same patients.

Methods

This retrospective study compared 45 patients who underwent rotator cuff repair between September 2021 and April 2022 and 41 patients with normal shoulders. The ACEA was measured by 2 independent observers on anteroposterior radiographs and shoulder MRI. The collected data were analyzed and P values of <.05 were considered statistically significant.

Results

The ACEA was found to be higher in patients with rotator cuff tears (23.48° ± 7.11°) when compared with the control group (15.54° ± 4.4°). On shoulder MRI assessment, a higher ACEA was also seen in the rotator cuff tear group (18.93° ± 6.7°) than in the control group (13.79° ± 4.9°). The ACEA measurement on MRI showed strong intrarater reliability (0.965), but weak interrater reliability (0.251).

Conclusion

This retrospective study found an association between increased ACEA and risk of rotator cuff tear when measured on plain radiographs. In addition, we found an association between increased ACEA measurement on shoulder MRI and rotator cuff tears, thus suggesting the applicability of ACEA measurement on shoulder MRI.

Critical Shoulder Angle in Patients With Cuff Tears

OBJECTIVE

The pathogenesis of rotator cuff tears (RCTs) is multifactorial. Critical shoulder angle (CSA), which represents the lateral extension of the acromion over the cuff, has been proposed as an extrinsic risk factor. The aim of the present systematic review and meta-analysis was to analyze the available literature regarding the correlation between RCT and CSA.

METHODS

A review was carried out in accordance with the "Preferred Reporting Items for Systematic reviews and Meta-Analyses" guidelines on July 17, 2023, using the following databases: PubMed, Ovid, and Cochrane Reviews. The following keywords were used: "critical shoulder angle," "rotator cuff tears," and "rotator cuff lesions." The methodological quality of the studies was assessed with the MINORS SCORE.

RESULTS

Twenty-eight studies were included. The average CSA among the 2110 patients with full-thickness RCT was 36.7 degrees, whereas the same value among the 2972 controls was 33.1 degrees. The average CSA in the 348 patients with partial-thickness RCT was 34.6 degrees, whereas it was 38.1 degrees in the 132 patients with massive RCT. The average MINORS score was 15.6.

CONCLUSIONS

CSA values were significantly higher in patients with RCT compared with the asymptomatic population. In addition, it appears that CSA values increase with the severity of rotator cuff involvement.

Effect of arthroscopic subacromial decompression during arthroscopic repair of small to medium-sized rotator cuff tears

Background

Although arthroscopic subacromial decompression (ASD) is a commonly used procedure during arthroscopic rotator cuff repair (ARCR), the effect of ASD on the clinical outcomes for ARCR is controversial. The purpose of this study was to compare the clinical outcomes of ARCR with or without ASD.

Methods

Patients (n = 315 with 320 shoulders) who underwent ARCR for small to medium-sized rotator cuff tears were followed for at least 24 months. ARCR was performed with ASD (180 shoulders, group A) or without ASD (140 shoulders, group N). There were no significant differences in patient demographics, including mean age and mean follow-up time. Rotator cuff repair was performed using the suture-bridge technique in all shoulders, and all patients were treated using the same rehabilitation protocol after surgery. University of California at Los Angeles score, Constant score, re-tear rates, revision surgery rates, and operating time were compared between groups. Re-tear was defined as Sugaya classification Types 4 and 5 using postoperative magnetic resonance imaging at more than 12 months.

Results

There was no statistically significant difference in clinical outcomes before and after ARCR between groups. However, the University of California at Los Angeles scores and Constant scores significantly improved in both groups after surgery (P < .001). Furthermore, there was no major difference in the re-tear rates between groups A (7/180 shoulders, 3.9%) and N (11/140 shoulders, 7.9%) (P = .146). Revision surgeries were performed on 3/180 shoulders (1.7%) in group A (due to postoperative deep infection in one shoulder and revision ARCR for re-tear in two shoulders). No revisions surgeries were needed in group N patients (P = .259). The mean surgical time for group A was 62.0 ± 27.0 minutes (29-138 min.) and 52.4 ± 26.1 minutes (17-124 min.) for group N (P = .007).

Conclusion

These results suggest that ASD has a limited effect on clinical outcomes of ARCR for small to medium-sized rotator cuff tears.