Chronicity is associated with the glenohumeral synovitis in patients with a rotator cuff tear

A comprehensive analysis of the acromial morphology and etiological factors of partial rotator cuff tears

Background

Rotator cuff tears are divided into complete and partial tears, and partial rotator cuff tears include articular-sided tears and bursal-sided tears. Tears are caused by extrinsic, intrinsic, or traumatic factors; however, the mechanisms by which partial tears occur remain unknown. Recent reports have described the correlation between acromial morphology and rotator cuff tears. To date, no reports have investigated acromial morphology in partial tears. The purpose of this study is to evaluate the incidence of abnormal acromial morphology in both partial articular-sided and bursal-sided rotator cuff tears.

Methods

Patients with supraspinatus tendons that had articular-sided tears were categorized into Group A, and patients who had bursal-sided tears were categorized into Group B. Patients who underwent arthroscopic rotator cuff repair for rotator cuff tears were assessed based on their diagnosis of Group A or Group B according to arthroscopic findings. The following items were examined: age, sex, presence of diabetes mellitus, acromiohumeral distance (AHD), critical shoulder angle (CSA), lateral acromial angle (LAA), sagittal and coronal morphologies of the acromion, and traumatic shoulder tears.

Results

There were 39 patients in Group A and 95 patients in Group B. A significantly greater rate of presence of diabetes was found in the Group A. There were no significant differences in age, sex, or frequency of traumatic shoulder tears. The mean AHD, CSA, and LAA in Group A and Group B were as follows: AHD, 9.4 ± 1.5 and 9.3 ± 1.4 mm; CSA, 32.1 ± 4.6 and 35.3 ± 4.4 degrees; LAA, 82.2 ± 7.2 and 79.9 ± 7.0 degrees. There were no significant differences between the groups. Although the CSA was significantly greater in Group B, there was no significant difference in the AHD or LAA. There was no significant difference in sagittal acromial morphology; however, Group B had significantly more inferior osteophytes of the acromial center in the coronal plane.

Conclusion

Group B was found to have a significantly larger mean CSA compared to Group A. Group B occurred more often in patients with inferior osteophytes of the acromial center on the acromion, suggesting the involvement of extrinsic factors.

The degenerated glenohumeral joint

Aims

This study aimed to define the histopathology of degenerated humeral head cartilage and synovial inflammation of the glenohumeral joint in patients with omarthrosis (OmA) and cuff tear arthropathy (CTA). Additionally, the potential of immunohistochemical tissue biomarkers in reflecting the degeneration status of humeral head cartilage was evaluated.

Methods

Specimens of the humeral head and synovial tissue from 12 patients with OmA, seven patients with CTA, and four body donors were processed histologically for examination using different histopathological scores. Osteochondral sections were immunohistochemically stained for collagen type I, collagen type II, collagen neoepitope C1,2C, collagen type X, and osteocalcin, prior to semiquantitative analysis. Matrix metalloproteinase (MMP)-1, MMP-3, and MMP-13 levels were analyzed in synovial fluid using enzyme-linked immunosorbent assay (ELISA).

Results

Cartilage degeneration of the humeral head was associated with the histological presentation of: 1) pannus overgrowing the cartilage surface; 2) pores in the subchondral bone plate; and 3) chondrocyte clusters in OmA patients. In contrast, hyperplasia of the synovial lining layer was revealed as a significant indicator of inflammatory processes predominantly in CTA. The abundancy of collagen I, collagen II, and the C1,2C neoepitope correlated significantly with the histopathological degeneration of humeral head cartilage. No evidence for differences in MMP levels between OmA and CTA patients was found.

Conclusion

This study provides a comprehensive histological characterization of humeral cartilage and synovial tissue within the glenohumeral joint, both in normal and diseased states. It highlights synovitis and pannus formation as histopathological hallmarks of OmA and CTA, indicating their roles as drivers of joint inflammation and cartilage degradation, and as targets for therapeutic strategies such as rotator cuff reconstruction and synovectomy.

Transcriptome sequencing reveals inflammation and macrophage heterogeneity in subacromial bursa from degenerative shoulder disorders

PURPOSE

We aimed to investigate the transcriptomic alterations that occur in the subacromial bursa (SAB) following degenerative or traumatic shoulder diseases.

MATERIALS AND METHODS

RNA sequencing was employed to evaluate the transcriptomic alterations of the SAB in individuals afflicted with degenerative rotator cuff tear (RCT), traumatic RCT and proximal humerus fracture (PHF). To gain insights into the biological significance of differentially expressed genes (DEGs), we conducted an enrichment analysis utilizing Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. We further utilized single-cell RNA sequencing datasets of SAB from a recently published study to explore the associated cellular dynamics and alterations.

RESULTS

We detected 1,790 up-regulated and 1,964 down-regulated DEGs between degenerative RCT and PHF, 2,085 up-regulated and 1,919 down-regulated DEGs between degenerative RCT and traumatic RCT, and 20 up-regulated and 12 down-regulated DEGs between traumatic RCT and PHF. Given the similar expression pattern between traumatic RCT and PHF, they were integrated as the traumatic group. In comparison with the traumatic group, 1,983 up-regulated and 2,205 down-regulated DEGs were detected in degenerative SAB. Enrichment analysis of up-regulated DEGs uncovered an elevated inflammatory and immunologic responses in degenerative SAB. Single-cell transcriptomic analysis revealed macrophage represented the immune cell with the most DEGs between the degenerative and traumatic RCT.

CONCLUSION

Our results revealed that the SAB in degenerative RCT exhibited a different transcriptional signature compared to that in traumatic RCT, and enrichment analysis showed immunologic and inflammatory activations. Macrophages may play a fundamental role in this process.

Blood flow velocity in the anterior humeral circumflex artery and tear size can predict synovitis severity in patients with rotator cuff tears

BACKGROUND

Rotator cuff tears are often associated with synovitis, but the ability of noninvasive ultrasonography to predict the severity of synovitis remains unclear. We investigated whether ultrasound parameters, namely peak systolic velocity in the anterior humeral circumflex artery and Doppler activity in the glenohumeral joint and subacromial space, reflect synovitis severity.

METHODS

A total of 54 patients undergoing arthroscopic rotator cuff repair were selected. Doppler ultrasound was used to measure peak systolic velocity in the anterior humeral circumflex artery and Doppler activity in the glenohumeral joint and subacromial space, and these values were compared with the intraoperative synovitis score in univariate and multivariate analyses.

RESULTS

Univariate analyses revealed that tear size, peak systolic velocity in the anterior humeral circumflex artery, and Doppler activity in the glenohumeral joint were associated with synovitis in the glenohumeral joint (P=0.02, P<0.001, P=0.02, respectively). In the subacromial space, tear size, peak systolic velocity in the anterior humeral circumflex artery, and Doppler activity in the subacromial space were associated with synovitis severity (P=0.02, P<0.001, P=0.02, respectively). Multivariate analyses indicated that tear size and peak systolic velocity in the anterior humeral circumflex artery were independently associated with synovitis scores in both the glenohumeral joint and the subacromial space (all P<0.05).

CONCLUSIONS

These findings demonstrate that tear size and peak systolic velocity in the anterior humeral circumflex artery, which can both be measured noninvasively, are useful indicators of synovitis severity. Level of evidence: IV.

Shoulder Intra-Articular Temperature Is Higher In Patients With Small Rotator Cuff Tears Compared With Patients Who Have Larger Tears

Purpose

The purpose of this study was to determine whether the intra-articular temperature of the shoulder correlates with the size of the tendon tear in patients with rotator cuff tears (RCTs).

Methods

The shoulder intra-articular temperature of 75 consecutive (32 female, 43 male; mean age 61.12; standard deviation = 7.10) patients who underwent arthroscopic rotator cuff repair was measured with a digital thermometer, at first in 2 points (biceps anchor and glenoid labrum) during dry arthroscopy, followed by a third measurement during wet arthroscopy. A fourth measurement, represented by the patient's axillary body temperature, was taken upon admission. The RCTs were classified during surgery according to the Southern California Orthopedic Institute classification system as small, large, and massive. Data were submitted for statistical analysis.

Results

The intra-articular temperature differs in patients with different-sized RCTs regardless of the location of the thermometer. A significantly higher temperature was found in patients with small RCTs (36.2°C ± 0.57°C) (P < .01). When the in-flow of the arthroscopic fluid was opened, the temperature dropped to an average of 24.5°C.

Conclusions

The shoulder intra-articular temperature was significantly associated with RCT size. A significantly higher temperature was found in small RCTs. No correlation was found between age and sex, age and RCT size, sex and RCT size, or sex and temperature.

Clinical Relevance

An early diagnosis and treatment of RCTs may avoid further degeneration and damage of the tendon caused by the increased temperature.

Clinical Implication of Glenohumeral and Subacromial Synovitis in Rotator Cuff Tears

Background

Synovitis of the glenohumeral (GH) joint and the subacromial (SA) space is commonly observed during arthroscopic rotator cuff surgery.

Purpose

To investigate the distribution, severity, and clinical implications of synovitis in the GH joint and SA space in patients with a full-thickness rotator cuff tear (RCT).

Study Design

Case series; Level of evidence, 4.

Methods

Data were retrospectively collected from 207 patients with a full-thickness RCT who underwent arthroscopic repair. Preoperative parameters used in the clinical assessment included pain, range of motion (ROM), muscle strength, and functional scores. Macroscopic assessment of synovitis was performed intraoperatively in the 3 regions of interest (ROIs) of the GH joint and 4 ROIS of the SA space using an evaluation system. The distribution and severity of synovitis and the association between synovitis and clinical assessment were evaluated.

Results

Synovitis was more severe in the GH joint than in the SA space (P < .001). Synovitis in the posterior GH joint and the lateral SA space, where most of the rotator cuff was located, was the most severe area among the ROIs of the GH joint and the SA space, respectively (P < .05). All types of pain, except for pain at rest, were associated with synovitis in the posterior GH joint (P < .05). All ROM measures were associated with synovitis in the posterior and inferior GH joint (|r| > 0.20; P < .05 for both). The strength of the supraspinatus and the infraspinatus was associated with synovitis in the posterior GH joint (P < .05). Shoulder function was associated with synovitis in the posterior and inferior GH joint and more in the posterior GH joint (P < .05 for both). Synovitis in the SA space was not associated with any of the clinical parameters.

Conclusion

Synovitis in the posterior GH joint was the most severe form of synovitis in the GH joint in patients with a full-thickness RCT. Synovitis in the posterior GH joint was closely associated with increased pain and decreased ROM, muscle strength, and functional score. Synovitis in the SA space was milder and not associated with any clinical parameters.

Shoulder Synovitis Does not Affect Pain After Arthroscopic Rotator Cuff Repair

Background

The goal of this study was to determine if there is an association between glenohumeral synovitis and early post-operative pain after arthroscopic rotator cuff repair.

Methods

Fifty patients with symptomatic rotator cuff tears were prospectively enrolled prior to RCR. Baseline ASES score, VAS Pain score, forward elevation, and external rotation were recorded. Intra-operatively, synovitis was graded on a scale of zero to six as based on a previously validated scoring system. VAS Pain scores were obtained from patients post-operatively on days one through 14, week 6, and 3 months.

Results

Average intra-operative synovitis score was 2.4 ± 1.6. No significant correlation was found between synovitis score and pre-operative forward elevation (P=0.171), external rotation (P=0.126), VAS Pain (P=0.623), or ASES (P=0.187) scores. No significant correlation was found between synovitis score and post-operative VAS Pain level at any time point. There was a moderate correlation between both pre-operative VAS Pain and ASES scores and post-operative VAS Pain in the first post-operative week. Workers' compensation patients had worse pain at 3 months post-operatively compared to non-workers compensation patients (P=0.038).

Conclusion

This study reveals that macroscopically assessed glenohumeral synovitis does not have any significant correlation with pre-operative or post-operative pain in patients undergoing arthroscopic rotator cuff repair; although higher pre-operative pain levels, worse pre-operative ASES scores, and workers compensation status do influence post-operative pain levels in arthroscopic rotator cuff repair.