Subacromial volume and rotator cuff tears: Does an association exist?

Scapular morphology does not predict supraspinatus tendon tear propagation following an individualised exercise therapy programme

Purpose

To determine whether scapular morphology could predict isolated supraspinatus tendon tear propagation after exercise therapy. We hypothesised that a larger critical shoulder angle (CSA) and type III acromial morphology predict a positive change in tear size.

Methods

Fifty-nine individuals aged 40-70 years with isolated symptomatic high-grade partial or full-thickness supraspinatus tendon tears were included. Individuals participated in a structured, individualised 12-week exercise therapy programme and underwent ultrasound to measure tear size at baseline and 12 months following therapy. Computed tomography images were segmented to create three-dimensional subject-specific bone models and reviewed by three trained clinicians to measure CSA and to determine acromion morphology based on the Bigliani classification. A binary logistic regression was performed to determine the predictive value of CSA and acromion morphology on tear propagation.

Results

The CSA was 30.0 ± 5.4°. Thirty-one individuals (52.5%) had type II acromial morphology, followed by type III and type I morphologies (25.4% and 22.0%, respectively); 81.4% experienced no change in tear size, four (6.8%) individuals experienced tear propagation and seven (11.9%) individuals had a negative change in tear size. No significant difference in tear propagation rates based on CSA or acromion morphology (not significant [NS]) was observed. The model predicted tear size status in 81.4% of cases but only predicted tear propagation 8.3% of the time. Overall, CSA and acromion morphology only predicted 24.3% (R 2 = 0.243) of variance in tear propagation (NS).

Conclusions

CSA and acromion morphology were NS predictors of tear propagation of the supraspinatus tendon 12 months following an individualised exercise therapy programme.

Level of Evidence

II.

Simulated subacromial injection instruction improves accuracy and skill level: a model for musculoskeletal procedural training

BACKGROUND

Musculoskeletal (MSK) complaints often present initially to primary care physicians; however, physicians may lack appropriate instruction in MSK procedures. Diagnostic and therapeutic injections are useful orthopedic tools, but inaccuracy leads to unnecessary costs and inadequate treatment. The authors hypothesized that trainees afforded the opportunity to practice on a cadaver versus those receiving visual-aided instruction on subacromial injections (SAI) will demonstrate differences in accuracy and technique.

METHODS

During Spring of the year 2022, 24 Internal Medicine and Family Medicine residents were randomly divided into control and intervention groups to participate in this interventional randomized cadaveric study. Each group received SAI instruction via lecture and video; the intervention group practiced on cadavers under mentored guidance. Subjects underwent a simulated patient encounter culminating in injection of latex dye into a cadaveric shoulder. Participants were evaluated based on a technique rubric, and accuracy of injections was assessed via cadaver dissection.

RESULTS

Twenty-three of twenty-four participants had performed at least one MSK injection in practice, while only 2 (8.3%) of participants had performed more than 10 SAIs. There was no difference in technique between control 18.4 ± 3.65 and intervention 19.2 ± 2.33 (p = 0.54). Dissections revealed 3 (25.0%) of control versus 8 (66.7%) of intervention injections were within the subacromial space. Chi-Square Analysis revealed that the intervention affected the number of injections that were within the subacromial space, in the tissues bordering the subacromial space, and completely outside the subacromial space and bordering tissues (p = 0.03). The intervention group had higher self-confidence in their injection as opposed to controls (p = 0.04). Previous SAI experience did not affect accuracy (p = 0.76).

CONCLUSIONS

Although primary care physicians and surgeons develop experience with MSK procedures in practice, this study demonstrates a role for early integrated instruction and simulation to improve accuracy and confidence. The goal of improving accuracy in MSK procedures amongst all primary care physicians may decrease costs and avoid unnecessary referrals, diagnostic tests, and earlier than desired surgical intervention.

Volumetric Analysis of Subacromial Space After Superior Capsular Reconstruction for Irreparable Rotator Cuff Tears

Purpose

Subacromial volume measurement on magnetic resonance images is relatively new. It has been shown that decreased subacromial volume increases after surgical repair of full-thickness rotator cuff tears. There is no study examining subacromial volume changes after superior capsular reconstruction (SCR). The purpose of this study was to compare subacromial volume changes on magnetic resonance images (MRI) after superior capsular reconstruction performed for primary irreparable rotator cuff tears.

Methods

Patients who underwent an SCR procedure between 2017 and 2019 with a minimum 2-year postoperative follow-up were included in this retrospective study. Subacromial volume was measured on MRI using software. The preoperative and postoperative acromiohumeral distance, Constant Scores, graft thickness, and Hamada grades of the patients were evaluated.

Results

A total of 18 patients with a mean age of 59.7 years (range: 49-74 years) underwent an SCR for massive irreparable cuff tear. The mean preoperative subacromial volume was 3.54 ± 0.39 cm3 (range 2.88-4.36 cm3), which increased to 4.46 ± 0.39 cm3 (range 3.75-5.32 cm3) postoperatively (p =  < 0.001). The increase in subacromial volume and acromiohumeral distance did not correlate with Constant scores and graft thickness. We observed a significantly higher subacromial volume increase among Hamada grade 1 patients, compared to those with Hamada grade 2 (p = 0.011).

Conclusions

We observed that subacromial volume significantly increased after superior capsular reconstruction. However, the increase in subacromial volume did not correlate with clinical scores, acromiohumeral distance changes, or graft thickness.Level of evidence: Level III - Retrospective Cohort Study.

Volumetric evaluation of the subacromial space in shoulder impingement syndrome

INTRODUCTION

Shoulder impingement syndrome is evaluated radiologically with two-dimensional measurement parameters. None of these measurement parameters accurately reflect the three-dimensional geometry. The purpose of this study was to evaluate the volumetric status of the subacromial space in patients with shoulder impingement syndrome and to investigate its relationship with two-dimensional parameters.

HYPOTHESIS

The primary hypothesis of this study is that subacromial volume is reduced in patients with impingement syndrome. The second hypothesis is that the sagittal plane morphology of the acromion reflects the subacromial volume better than the coronal plane morphology.

PATIENTS AND METHODS

This retrospective study consisted of a total of 52 participants: 26 patients with impingement syndrome and 26 controls. Volumetric measurements were performed with using magnetic resonance imaging. The relationship between humerus and acromion was evaluated by acromiohumeral distance. The sagittal plane morphology of the acromion was evaluated with an objective acromial angle, while the coronal plane morphology was evaluated with a lateral acromial angle. The radiological parameters between groups were compared.

RESULTS

The mean subacromial volume was significantly smaller in the impingement group compared to the control group (p=0.01). The subacromial volume had a negative correlation with the objective acromial angle (R=-0.46; p=0.01) The mean tendon volume was significantly higher in the impingement group (p<0.001). The mean acromiohumeral distance in the impingement group (6.8mm±1.0mm), was calculated to be significantly lower than the control group (10.1mm±1.5mm) (p<0.001). There was a positive moderate correlation between subacromial volume and acromiohumeral distance (R=0.61; p=0.01).

DISCUSSION

This is the first study to demonstrate a reduction in subacromial volume in patients with impingement syndrome. The sagittal plane morphology of the acromion, rather than the coronal plane, appears to be more closely related to the subacromial volume.

LEVEL OF EVIDENCE

III; case-control study.

Comparison of local infiltration analgesia and interscalene block for postoperative pain management in shoulder arthroscopy: a prospective randomized controlled trial

Background/aim

The aim of this study was to compare the effects of local infiltration analgesia and interscalene brachial plexus block techniques on postoperative pain control and shoulder functional scores in patients undergoing arthroscopic rotator cuff repair.

Materials and methods

Sixty patients who underwent arthroscopic rotator cuff repair were prospectively included in the study. Patients were randomly divided into two groups. Group 1 was comprised of patients who had interscalene brachial plexus block, while group 2 was comprised of patients who had local infiltration analgesia. In group 1, interscalene block was applied with 20 mL 0.5% bupivacaine. In group 2, the Ranawat cocktail was used for local infiltration analgesia. Sixty milliliters of Ranawat cocktail was applied to the subacromial space and glenohumeral joint in equal amounts. Postoperative pain was assessed by the VAS score. Functional scores of the shoulder were also evaluated by Constant–Murley and UCLA scores. The time of first analgesic requirement and total analgesic consumption in the postoperative period were assessed.

Results

The first analgesic requirement was significantly late in the interscalene brachial plexus block group (p = 0.000). There was no statistically significant difference between the groups in terms of total analgesic consumption (p = 0.204). In the postoperative 6th h, the VAS score was 2.43 in the interscalene brachial plexus block group, whereas 2.86 in the local infiltration analgesia group (p = 0.323). There was no statistically significant difference between the groups in terms of Constant–Murley shoulder and UCLA scores in the 3rd postoperative month (respectively, p = 0.929, p = 0.671). Besides, postoperative VAS scores and functional scores were negatively correlated (p < 0.01).

Conclusion

Local infiltration analgesia is an effective alternative to interscalene brachial plexus block for postoperative pain management and total analgesic consumption in arthroscopic rotator cuff repair. However, the interscalene brachial plexus block provides a longer postoperative painless period.

Engineering multi-tissue units for regenerative Medicine: Bone-tendon-muscle units of the rotator cuff

Our body systems are comprised of numerous multi-tissue units. For the musculoskeletal system, one of the predominant functional units is comprised of bone, tendon/ligament, and muscle tissues working in tandem to facilitate locomotion. To successfully treat musculoskeletal injuries and diseases, critical consideration and thoughtful integration of clinical, biological, and engineering aspects are necessary to achieve translational bench-to-bedside research. In particular, identifying ideal biomaterial design specifications, understanding prior and recent tissue engineering advances, and judicious application of biomaterial and fabrication technologies will be crucial for addressing current clinical challenges in engineering multi-tissue units. Using rotator cuff tears as an example, insights relevant for engineering a bone-tendon-muscle multi-tissue unit are presented. This review highlights the tissue engineering strategies for musculoskeletal repair and regeneration with implications for other bone-tendon-muscle units, their derivatives, and analogous non-musculoskeletal tissue structures.

Is Bony Morphology and Morphometry Associated With Degenerative Full-Thickness Rotator Cuff Tears? A Systematic Review and Meta-analysis

PURPOSE

To scope the scientific literature and analyze the influence of bony risk factors for degenerative full-thickness primary rotator cuff tear.

METHODS

A systematic review of databases PubMed, Scopus, EMBASE, and Cochrane Library was performed up to June 30, 2018. Meta-analysis was performed with mean difference (MD) or risk ratio for degenerative full-thickness rotator cuff injury, and when there were ≥3 studies for the considered potential risk factor. Methodologic quality was assessed using the Newcastle-Ottawa scale.

RESULTS

We analyzed 34 studies comprising 5,916 shoulders (3,369 shoulders with rotator cuff tear and 2,546 controls) and identified 19 potential risk factors for degenerative full-thickness rotator cuff tears. There was moderate evidence that a higher critical shoulder angle (MD = 4.41, 95% confidence interval [CI] 3.43 to 5.39), higher acromion index (MD = 0.06, 95% CI 0.04 to 0.09), and lower lateral acromion angles (MD = -7.11, 95% CI -8.32 to -5.90) were associated with degenerative full-thickness rotator cuff tears compared with controls. Moderate evidence showed that a type III acromion significantly increases the risk for full-thickness degenerative rotator cuff tear (risk ratio = 2.26, 95% CI 1.38 to 3.70).

CONCLUSION

There is moderate evidence that larger critical shoulder angle, higher acromion index, lower lateral acromion angles, and a type III acromion are significantly associated with degenerative full-thickness rotator cuff tears. Other potential risk factors identified showed insufficient evidence.

LEVEL OF EVIDENCE

Level IV, systematic review of level II to IV studies.

Subacromial space volume in patients with rotator cuff tear: The effect of surgical repair

Objective

The aim of this study was to evaluate the effect of the rotator cuff tear repair on subacromial space volume.

Methods

We retrospectively identified 21 eligible patients (5 males and 16 females; mean age: 56.4 (range; 46–71) years) who had shoulder arthroscopy for unilateral full-thickness small to medium rotator cuff tear and normal controlateral shoulder joint. The mean follow-up time was 16.1 (range; 12–25) months. Preoperative and postoperative 1 year bilateral shoulder MRIs and Constant scores were reviewed. Subacromial volume was calculated by using Osirix software. Pre-, postoperative and healthy side (contralateral control group) subacromial volumes were recorded. Paired sample and t-tests were used to compare the pre- and postoperative groups. Independent sample t-tests were used to compare the healthy and pre- and postoperative groups. The correlation between the changes in the subacromial volume and the shoulder Constant score were analyzed using Pearson correlation analyses.

Results

The mean subacromial volume of the preoperative group was 2.95 cm³ (range; 1.53–4.23) and the postoperative group was 3.59 cm³ (range; 2.12–4.84). The volume increase was statistically significant (p < 0.05). The mean subacromial volume of the control group was 3.93 cm³ (range; 2.77–5.03), and the difference between the preoperative group and the control group was statistically significant. There was no significant difference found between the postoperative group and the control group (p = 0.156). There was no significant correlation found between the volume and the constant score changes (r = 0.170, p = 0.515).

Conclusion

The subacromial space volume significantly decreases in full-thickness rotator cuff tears smaller than 3 cm and the surgical repair increases the subacromial volume significantly.

Level of evidence

Level IV; Diagnostic Study.