Relation between narrowed coracohumeral distance and subscapularis tears

Higher Upper Subscapularis Goutallier Grade and Coracohumeral Distance Narrowing Are Predictive of Subscapularis Tears in Patients Undergoing Arthroscopic Rotator Cuff Repair

PURPOSE

To evaluate the relation between subscapularis (SSC) Goutallier grade or coracohumeral distance (CHD) and SSC tears, as well as the relation between these radiographic variables and long head of the biceps tendon lesions.

METHODS

A retrospective analysis was conducted on prospectively maintained data on patients who underwent arthroscopic rotator cuff repair of SSC tears between 2011 and 2021 with at least 6 months of follow-up. Patients with identified subscapularis tears during arthroscopy were included. A control group was established by randomly selecting patients without SSC tears from the same study period. Goutallier grading and CHD were obtained from preoperative magnetic resonance imaging (MRI) scans. Receiver operating characteristic analysis was conducted to define optimal cutoff values for these diagnostic measures.

RESULTS

The study included 735 patients with SSC tears and 249 patients in the control group. Comparing subscapularis tear and intact groups' Goutallier grades revealed significant differences in infraspinatus, upper and lower SSC, and overall SSC (P < .001). No significant difference was detected in supraspinatus Goutallier grade (P = .364). An SSC tear was observed in 58.3% (n = 265) of patients with Goutallier grade 0 of the upper SSC, 77.1% (n = 195) of patients with grade 1 changes, 98.7% (n = 155) with grade 2 changes, and 100% of grade 3 or 4 changes. Goutallier grade of the upper SSC showed a significant correlation with tear size (rs = 0.533; P < .01). CHD measurements were lower in individuals with SSC tears compared to those without tears (6.6 ± 1.7 vs 9.6 ± 1.8; P < .001). Upper SSC Goutallier grade >1 had an acceptable area under the curve (AUC) of 0.742. CHD of 7.96 mm or less had an excellent predictive AUC of 0.879.

CONCLUSIONS

Higher Goutallier grade and CHD narrowing are potential associations predictive of SSC tears. Routine MRI assessment of muscle of the upper SSC and the CHD can contribute to the diagnostic accuracy of SSC tears and offer valuable information regarding the severity of such tears.

LEVEL OF EVIDENCE

Level III, diagnostic study.

Patient-reported outcomes of arthroscopic repair for partial or full-thickness upper third subscapularis tendon tears with open sub-pectoral biceps tenodesis: minimum 10-year outcomes

BACKGROUND

Although short-term results are promising, there are limited data for long-term results of arthroscopic subscapularis (SSC) repair. The purpose of this study is to report minimum 10-year outcomes of primary arthroscopic repair of isolated partial or full-thickness tears of the upper third of the SSC tendon.

METHODS

Patients who underwent arthroscopic repair of isolated upper third SSC tears, Lafosse type I (>50% of tendon thickness) or type II were included. Surgeries were performed by a single surgeon between November 2005 and August 2011. Patient-reported outcome measures were prospectively collected and retrospectively reviewed at minimum follow-up of 10 years. Patient-reported outcomes utilized included the American Shoulder and Elbow Surgeons score, Single Assessment Numeric Evaluation score (SANE), Quick Disabilities of the Arm, Shoulder and Hand score (QuickDASH), the Short Form 12 physical component summary, return to activity, and patient satisfaction. A subanalysis of patient age and outcomes was performed. Retears, revision surgeries, and surgical complications were recorded.

RESULTS

In total, 29 patients with isolated upper third SSC repairs were identified. After application of exclusion criteria, 14 patients were included in the final analysis. Follow-up could be obtained from 11 patients. The mean age at surgery was 52.7 years (range: 36-72) and the mean follow-up was 12 years (range 10-15 years). The American Shoulder and Elbow Surgeons score improved from 52.9 ± 21.8 preoperatively to 92.2 ± 13.7 postoperatively (P < .001). Regarding the SANE and QuickDASH scores, only postoperative data were available. Mean postoperative SANE, QuickDASH, and Short Form 12 physical component summary scores were 90.27 ± 10.5, 14.6 ± 15.5, and 49.2 ± 6.6, respectively. Median patient satisfaction was 10 (range 6-10). Patients reported improvements in sleep, activities of daily living, and sports. There was no correlation between patient age and clinical outcome (P > .05). No patients underwent revision surgery for a SSC retear.

CONCLUSION

Arthroscopic repair of upper third SSC tendon tears leads to improved clinical scores and high patient satisfaction at minimum 10-year follow-up. The procedure is durable, with no failures in the presented cohort.

Anterior capsular reconstruction in irreparable subscapularis tear: human dermal allograft

BACKGROUND

The irreparable subscapularis (SSc) tears pose an extremely difficult situation to manage, especially in the younger population. The anterior capsular reconstruction (ACR) with human dermal allograft (HDA) is an alternative to tendon transfer with sound biomechanical advantages and clinical outcomes. The purpose of this study was to evaluate the early clinical and radiologic outcomes of open ACR with HDA in patients with irreparable SSc tears.

METHODS

Eighteen patients who had an open ACR with HDA for irreparable SSc tears between August 2020 and January 2022 were enrolled. There were 11 male and 7 female patients with a mean age of 63.7 years and a mean follow-up of 17 months (range, 12-28 months). The dominant side was affected in 10 patients. One of the 18 patients had reconstruction with single-layer HDA, 14 had double-layer HDA, and 3 had SSc augmentation over double-layer HDA. Clinical and radiologic outcomes were assessed and compared pre- and postoperatively.

RESULTS

There was significant improvement in visual analog scale score from 6.6 ± 1.6 to 1.6 ± 1.5 (P < .001) and in the total University of California-Los Angeles shoulder score from 12.4 ± 4.3 to 29.0 ± 4.5 (P < .001). Forward flexion, abduction, and internal rotation (IR) increased by 28.6°, 32.5°, and 11.8°, respectively (P < .001). External rotation decreased by 6.4° (P = .020). There was notable improvement in IR strength (percentage of that of the opposite, normal side) from 66.0% ± 19.4% to 84.4% ± 22.3% (P = .008). The mean postoperative coracohumeral distance improved from 3.0 to 6.0 mm (P < .001), the anterior translation of the humeral head reduced from 1.5 to 0.5 mm (P = .210), and the acromiohumeral interval from 8.1 to 8.8 mm (P = .070). The patients' satisfaction at final follow-up was rated 4.1 of 5.0 (P < .001). Sixteen of 18 patients (88.9%) had the HDA healed at the glenoid and humeral side, and 2 (11.1%) had retear at the final follow-up. Among the 17 who had double-layer HDA, none showed any healing between the layers.

CONCLUSION

This study showed that early significant and comprehensive improvement inclusive of pain relief, improvement in range of motion, IR strength, and reduction of anterosuperior translation was achievable by open ACR with HDA for irreparable SSc tear.

Prospective Randomized Clinical Trial of Arthroscopic Repair Versus Debridement for Partial Subscapularis Tendon Tears More Than Half of the Entire First Facet

BACKGROUND

Most outcome studies on subscapularis (SSC) tendon tears have focused on large SSC tears rather than partial SSC tendon tears. Therefore, the optimal treatment for partial SSC tendon tears more than half of the first facet of the entire SSC footprint has not yet been clearly defined.

PURPOSE

To prospectively investigate the clinical and radiological results between the arthroscopic repair group and the debridement group in SSC partial tear (Yoo and Rhee classification, type 2B: SSC tendon tears of more than half of the entire first facet).

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

A total of 65 patients with SSC tendon type 2B tears were randomized to arthroscopic debridement (n = 33) or arthroscopic repair (n = 32). Clinical evaluation of the patients was performed on the day before surgery and 6 months, 1 year, 2 years, and 5 years postoperatively using active range of motion measurements and other validated scores (pain visual analog scale scores, function visual analog scale scores, Constant score, American Shoulder and Elbow Surgeons score). In addition, SSC muscle strength was measured using instruments in the belly-press position. Magnetic resonance imaging (upper and lower SSC muscle diameters, Goutallier grades) was performed on the day before operation as well as 6 months and 2 years postoperatively.

RESULTS

There were no clinically or statistically significant differences between the arthroscopic debridement and arthroscopic repair groups with respect to active range of motion, pain visual analog scale scores, function visual analog scale scores, Constant scores, or American Shoulder and Elbow Surgeons scores. There was a statistically significant increase in SSC muscle strength in the repair group compared with the debridement group at 5 years postoperatively (P = .013). Magnetic resonance imaging assessment was also not significantly different between the 2 groups.

CONCLUSION

There were no differences in the patient-reported outcomes of patients with partial SSC tears treated with either arthroscopic debridement or repair, although there was an increase in SSC muscle strength associated with repair, the clinical importance of which may warrant further research.

REGISTRATION

NCT03183466 (ClinicalTrials.gov identifier).

Subscapularis tear classification implications regarding treatment and outcomes: consensus decision-making

Background

Several classifications have been proposed for subscapularis tendon tearing (SCTs); however, there remains a poor agreement between orthopedic surgeons regarding the diagnosis and management of these lesions. Distinguishing the various tear patterns and classifying them with some prognostic significance may aid the operating surgeon in planning appropriate treatment.

Purpose

The purpose of this study was to outline the current literature regarding SCT classification and treatment and conduct a survey among shoulder and elbow surgeons to identify the approaches regarding surgical decision-making for these injuries.

Methods

In this systematic review, we analyzed 12 articles regarding the subscapularis tendon tear classification and implications regarding treatment plans and outcomes. In addition, 4 international experts in subscapularis repair surgery participated in the development of a questionnaire form that was distributed to 1161 ASES members. One hundred sixty five surgeons participated and chose whether they agree, disagree, or abstain for each of the 32 statements in 4 parts including indications/contraindications, treatment plan, and the factors affecting outcomes in the survey.

Results

Classification criteria were extremely variable with differing recommendations and descriptions of tear morphology; most were based on tear size, associated shoulder pathology, or lesser tuberosity footprint exposure. Considering the multiple classification systems and the overall poor agreement regarding SCT management, our study found that the most widely agreed upon (more than 80%) statements included early surgery is advised for traumatic SCT, chronic degenerative SCT (without fatty infiltration) associated with acute supraspinatus tear is a candidate for repair, and rotator cuff arthropathy is a contraindication for SCT repair.

Conclusion

Our study was able to identify both patient and tear characteristics that are well agreed upon among surgeons in the treatment of these injuries. Lafosse classification is generally widely accepted; however, it needs to be improved by some additions. Continued collaboration among surgeons is needed to establish an acceptable and broadly applicable classification system for the management of these injuries.

Is it the subcoracoid impingement or the subacromial impingement that tears the subscapularis tendon? A comparison of the MRI findings of the operated and healthy shoulders of the patients

BACKGROUND

: The purpose of this study is to investigate whether the etiological factors accepted as causes of idiopathic subscapularis tears are true or not when the comparison is made with the opposite side healthy shoulder of the patients who underwent arthroscopic repair for an isolated subscapularis tear.

METHODS

Sixteen patients who underwent shoulder arthroscopy between February 2016 and January 2018 and were diagnosed with isolated subscapularis tear were evaluated. The coracohumeral distance (CHDax), coracoid overlap (CO), and tuberculum minus cysts (TMC) were evaluated on the axial images of the MRI studies while the acromiohumeral distance (AHDsag), CHDsag, and subscapularis tendon slip number (STSN) on the sagittal oblique images and the AHDcor and SLAP lesion on the coronal oblique images. Degeneration of the coracoacromial ligament was evaluated during arthroscopy.

RESULTS

The mean CHDsag (11.26-10.08), CHDax (10.63-9.98), CO (14.2-15.43), AHDsag (8-7.66), and AHDcor (7.65-7.68) measurements (operated side-healthy side, respectively) were statistically similar (p > 0.05). No statistically significant difference was found between TMC and STSN in healthy and operated shoulders (p > 0.05). There was mild coracoacromial ligament fraying in 4 (25%) and obvious coracoacromial ligament fraying in 8 (50%) which indicated subacromial impingement in 75% of the patients.

DISCUSSION

The parameters of the coracoid process did not reveal any significant difference between the operated (for an isolated subscapularis tear) and opposite-side healthy shoulders of the patients. However, coracoacromial ligament degeneration was present in 75% of the patients.

Comparison of shoulder functions between assembly workers with and without subacromial pain syndrome

BACKGROUND: The occurrence of subacromial pain syndrome (SPS) is associated with the frequent handling and lifting of heavy loads and excessive repetitive work. Thus, assembly workers have a high prevalence of SPS. OBJECTIVE: The purpose of this study was to investigate differences in shoulder ROM, muscle strength, asymmetry ratio, function, productivity, and depression between workers with and without SPS. METHODS: Sixty-seven male workers (35 workers with SPS and 32 workers without SPS) participated in this study. Shoulder internal rotation (SIR), shoulder external rotation (SER), shoulder abduction (SAB), shoulder horizontal adduction ROM and SIR, SER, elbow flexion (EF), scapular depression and adduction, scapular protraction strength were measured. The asymmetry ratio was calculated using the asymmetry ratio formula; shoulder functions were measured using the shoulder pain and disability index (SPADI), disabilities of the arm, shoulder, and hand (DASH), and visual analogue scale (VAS); and Endicott work productivity scale (EWPS). RESULTS: The SPADI (p = 0.001), DASH (p = 0.001), and VAS (p = 0.001) values of workers with SPS were higher than those of workers without SPS. Also, workers with SPS had lower SIR (p = 0.001) and SAB (p = 0.002) ROM compared to workers without SPS. In addition, workers with SPS exhibited lower SIR (p = 0.012) strength than workers without SPS. Workers with SPS had higher asymmetry ratio in SIR (p = 0.015), SER (p = 0.005), and EF (p = 0.008) strength than workers without SPS. CONCLUSIONS: The SIR, SAB ROM, SIR strength, and the asymmetry ratio of SIR, SER, EF strengths could provide an important baseline comparison for the workers with SPS.

In Vivo Anatomical Research by 3D CT Reconstruction Determines Minimum Acromiohumeral, Coracohumeral, and Glenohumeral Distances in the Human Shoulder: Evaluation of Age and Sex Association in a Sample of the Chinese Population

Accurate measurement of the minimum distance between bony structures of the humeral head and the acromion or coracoid helps advance a better understanding of the shoulder anatomical features. Our goal was to precisely determine the minimum acromiohumeral distance (AHD), coracohumeral distance (CHD), and glenohumeral distance (GHD) in a sample of the Chinese population as an in vivo anatomical analysis. We retrospectively included 146 patients who underwent supine computed tomography (CT) examination of the shoulder joint. The minimum AHD, CHD, and GHD values were quantitatively measured using three-dimensional (3D) CT reconstruction techniques. The correlation between minimum AHD, CHD, and GHD value and age with different sexes was evaluated using Pearson Correlation Coefficient. The mean value of minimum AHD in males was greater than that in females (male 7.62 ± 0.98 mm versus female 7.27 ± 0.86 mm, p = 0.046). The CHD among different sexes differed significantly (male 10.75 ± 2.40 mm versus female 8.76 ± 1.38 mm, p < 0.001). However, we found no statistical differences in GHD with different sexes (male 2.00 ± 0.31 mm versus female 1.96 ± 0.36 mm, p > 0.05). In terms of age correlation, a negative curve correlation existed between age and AHD among the different sexes (male R2 = 0.124, p = 0.030, female R2 = 0.112, p = 0.005). A negative linear correlation was found in CHD among the different sexes (male R2 = 0.164, p < 0.001, female R2 = 0.122, p = 0.005). There were no differences between age and minimum GHD in both sexes. The 3D CT reconstruction model can accurately measure the minimum AHD, CHD, and GHD value in vivo and is worthy of further investigation for standard clinical anatomical assessment. Aging may correlate with AHD and CHD narrowing for both sexes.

Differences in Coracohumeral Distance Between the Symptomatic and the Asymptomatic Shoulder in Patients With Unilateral Shoulder Pain and in Healthy Participants: A Cross-Sectional Study

OBJECTIVES

The aim of this study was to analyze whether differences in the coracohumeral distance (CHD) exist between the symptomatic and the asymptomatic shoulder in patients with subacromial pain syndrome and compare with the shoulder of control participants.

METHODS

This was a cross-sectional, observational study. A sample comprising 62 participants with subacromial pain syndrome was recruited from 3 different primary care centers. The CHD was determined from standardized ultrasonography measures performed on both shoulders at 0° and 60° of shoulder abduction, whereas the dominant arm was measured for the control participants.

RESULTS

Statistically significant differences in CHD at 0° and 60° were found between the symptomatic and control shoulders (P = .011/P = .002) and between the contralateral asymptomatic shoulder and controls (P = .026/P = .007).

CONCLUSION

We found differences in CHD at 0° and 60° of shoulder elevation between both the affected and the nonaffected shoulders when compared with healthy shoulders. These results suggest that CHD may be a contributing factor in chronic shoulder pain.

Coracoid Impingement and Morphology Is Associated with Fatty Infiltration and Rotator Cuff Tears

This study describes measurements between the coracoid, glenoid, and humerus; characterizes coracoid shape, rotator cuff fatty infiltration, and quantitatively evaluates coracoid impingement and its association with anterosuperior rotator cuff tears (ASCT). 193 shoulder magnetic resonance imaging (MRI) scans demonstrating: rotator cuff tear; isolated tear of the supraspinatus; tear of supraspinatus and subscapularis, were included. MRI measurements included coracohumeral interval (CHI), coracoid overlap (CO), coracoid recess (CR), coracoglenoid angle (CGA), and coracoglenoid interval (CGI) on axial slices; acromiohumeral interval (AHI) on coronal slices; and coracohumeral interval (CHI) and coracoacromial ligament (CAL) thickness on sagittal slices. The coracoid shape was classified as flat, curved, or hooked. An Independent T-test was used to compare the MRI measurements and the different rotator cuff tear groups. In 79% of the patients with ASCT tears, the coracoid was curved. Axial CHI, CGA, sagittal CHI, and AHI were decreased in ASCT when compared to no tears and isolated supraspinatus tears (p < 0.05). CO was increased in ASCT compared to no tears and isolated supraspinatus tears (p < 0.05). Patients with an ASCT had a significantly increased subscapularis and supraspinatus Goutallier fatty infiltration score when compared to no tear and isolated supraspinatus tears (p < 0.05). These quantitative measurements may be useful in identifying patients at risk for ASCT. Level of Evidence III.

Relationship between the Hamada Grade and underlying pathological conditions in the rotator cuff and long head of biceps in symptomatic patients with rotator cuff tears

Background

This study aimed to investigate the relationship between Hamada Grade and rotator cuff and long head of the biceps (LHB) pathologies in symptomatic patients with rotator cuff tears (RCTs).

Methods

We retrospectively reviewed 376 patients (156 men and 220 women; mean age, 68.4 years) who had undergone surgery for complete RCTs. Preoperative plain radiography, magnetic resonance imaging, and intraoperative findings were assessed. All cases were allocated to the Hamada Grade 1, 2, 3, and 4-5 groups to investigate the correlation between Hamada Grade severity and underlying rotator cuff and LHB pathologies.

Results

The rate of RCTs involving the infraspinatus was significantly higher in Grade 2 than in Grade 1 (P < .0001). The tear size and fatty muscle degeneration of the subscapularis in Hamada Grade 3 were significantly more severe than those in Grade 2 (P = .01 and P < .0001, respectively). The tear size and fatty muscle degeneration of the rotator cuff in Grade 4-5 were significantly more severe than those in Grade 3 (all P < .05). The complete LHB rupture rate was significantly higher in Hamada Grade 4-5 than in Grades 1, 2, and 3 (all P < .001).

Conclusion

Rotator cuff tears involving the infraspinatus were associated with Hamada Grade 2. The rate of concomitant subscapularis tears with posterosuperior RCTs was significantly higher in Hamada Grade 3 than in Hamada Grade 2. RCT enlargement, progression of fatty muscle degeneration of the subscapularis and posterosuperior rotator cuff muscles, and the increase in complete LHB rupture were associated with Hamada Grade 4-5.

Current concepts review in the management of subscapularis tears

Subscapularis (SSc) is the prime internal rotator of shoulder. It is the most powerful rotator cuff muscle, maintaining the anterior force couple of shoulder. The tears in SSc as any other rotator cuff muscles might result from a traumatic event or more commonly from intrinsic degeneration. With the advent and widespread use of shoulder arthroscopy, SSc tears, which were once considered as "forgotten or hidden lesions" are now being increasingly recognized. Isolated SSc tears are relatively rare. They occur in combinations. Clinically internal rotation can be near normal because of the compensation provided by other internal rotators. It is not uncommon for patients with SSc tear to be normal on routine physical examination. The Bear Hug test (BHT) has high sensitivity and accuracy in the diagnosis of SSc tear. The combined use of BHT with Belly Press Test has been found optimal for diagnosis. US is an accurate and reliable method for diagnosing SSc tears and outperformed MRI in diagnosing partial-thickness SSc tears. The MRI is currently the most advanced imaging available for diagnosis. The specificity is up to 100%. However, the sensitivity is between 36 and 40%. The earliest classification system for SSc tears was by Fox et al. The commonly used classification is by Lafosse et al. The recent system by Yoo et al. is based on the insertion of SSc. The comma sign is gaining importance not only in arthroscopic diagnosis but also in MRI identification and repair of SSc. The mode of management is mainly arthroscopic. The techniques of repair of SSc are continuously progressing. However, there is no clear consensus on the double vs single-row repairs, biceps tendon management, and the role of coracoplasty. Future research must focus on these areas. Reserve shoulder arthroplasty is reserved for salvage in older age groups. Tendon transfers are performed in young active individuals with irreparable tears.

Biomechanical Analysis of Coracoid Stability After Coracoplasty: How Low Can You Go?

Background:

Arthroscopic coracoplasty is a procedure for patients affected by subcoracoid impingement. To date, there is no consensus on how much of the coracoid can be resected with an arthroscopic burr without compromising its stability.

Purpose:

To determine the maximum amount of the coracoid that can be resected during arthroscopic coracoplasty without leading to coracoid fracture or avulsion of the conjoint tendon during simulated activities of daily living (ADLs).

Study Design:

Controlled laboratory study.

Methods:

A biomechanical cadaveric study was performed with 24 shoulders (15 male, 9 female; mean age, 81 ± 7.9 years). Specimens were randomized into 3 treatment groups: group A (native coracoid), group B (3-mm coracoplasty), and group C (5-mm coracoplasty). Coracoid anatomic measurements were documented before and after coracoplasty. The scapula was potted, and a traction force was applied through the conjoint tendon. The stiffness and load to failure (LTF) were determined for each specimen.

Results:

The mean coracoid thicknesses in groups A through C were 7.2, 7.7, and 7.8 mm, respectively, and the mean LTFs were 428 ± 127, 284 ± 77, and 159 ± 87 N, respectively. Compared with specimens in group A, a significantly lower LTF was seen in specimens in group B (P = .022) and group C (P < .001). Postoperatively, coracoids with a thickness ≥4 mm were able to withstand ADLs.

Conclusion:

While even a 3-mm coracoplasty caused significant weakening of the coracoid, the individual failure loads were higher than those of the predicted ADLs. A critical value of 4 mm of coracoid thickness should be preserved to ensure the stability of the coracoid process.

Clinical Relevance:

In correspondence with the findings of this study, careful preoperative planning should be used to measure the maximum reasonable amount of coracoplasty to be performed. A postoperative coracoid thickness of 4 mm should remain.

Arthroscopic Subcoracoid Decompression, Coracoplasty, and Subscapularis Repair for Subscapularis Tears in the Setting of Subcoracoid Impingement

Subscapularis tears have been found to occur in the setting of subcoracoid impingement and are related to the narrowing of the coracohumeral interval. The advancement of arthroscopic techniques has allowed for improved identification and treatment of this historically overlooked pathology. Challenges of arthroscopic subscapularis treatment include nearby neurovascular structures, tendon retraction, and adhesions, which are further complicated by diminished arthroscopic visualization, resulting from the concomitant subcoracoid impingement. The purpose of this Technical Note is to describe our preferred technique for arthroscopic management of subscapularis tears in the setting of subcoracoid impingement that is simple and reproducible, as well as cost-effective and efficient with limited additional morbidity to that of a standard diagnostic shoulder arthroscopy.

Relationship between Radiological Measurement of Subcoracoid Impingement and Subscapularis Tendon Lesions

Background

The value of radiological measurements of subcoracoid impingement such as the coracohumeral interval in predicting subscapularis tendon injuries is controversial. We aimed to assess the relationship between radiological measurements of subcoracoid impingement and subscapularis tendon lesions in young and middle-aged adults.

Methods

This study was designed as a retrospective cohort study. Patients between the ages of 18–55 years without a history of shoulder surgery or major trauma were included and patients with arthritis, instability, or retracted rotator cuff tears were excluded from the study. Magnetic resonance images were evaluated and patients were grouped into two according to the subscapularis tendon condition: normal or pathologic. Glenoid version, axial coracohumeral distance, coracoglenoid angle, coracoid index, sagittal coracoid-glenoid tubercule distance, and axial coracoacromial inclination-glenoid version difference were measured for all patients. Measurement findings were compared between the groups. Correlation analysis was performed for age and radiologic measurements. A p < 0.05 was considered statistically significant for all tests.

Results

A total of 298 patients, 107 women (35.1%) and 191 men (64.9%), with a mean age of 34.46 ± 10.10 years (range, 18–55 years) were examined in the study. Subscapularis tendon pathology was noted in 85 patients (28.5%). The diagnosed pathologies were tendinosis in 48 patients (56.5%), partial tears in 28 (32.9%), and full thickness tears in 9 (10.6%). A significant relationship was observed between increasing age and subscapularis tendon lesions (p = 0.001). There was no statistically significant relationship between subscapularis pathology and calculated measurements. Axial coracohumeral distance and coracoglenoid angle measurements showed a statistically significantly negative correlation with age. A positive correlation was found between axial coracohumeral distance and coracoglenoid angle measurements (p < 0.001) and also between glenoid version and coracoid index measurements (p = 0.004). Axial coracohumeral distance and coracoglenoid angle measurements showed a negative correlation with glenoid version and coracoid index measurements (p < 0.05).

Conclusions

In this study, the coracohumeral distance and coracoglenoid angle decreased and the incidence of subscapularis tendon lesions increased as the age progressed. However, no relationship was found between radiological measurements and subscapularis tendon lesions.

Bilateral coracohumeral distance discrepancy is associated with subscapularis tear in rotator cuff rupture patients

PURPOSE

To describe the bilateral coracohumeral morphological discrepancy in rotator cuff rupture patients with and without subscapularis (SSC) involvement and to investigate its association with SSC tears.

METHODS

Two hundred and thirteen consecutive patients who were scheduled to have arthroscopic rotator cuff repair were prospectively enrolled in the current study. Patients with acute traumatic rotator cuff rupture, glenohumeral osteoarthritis, bilateral rotator cuff rupture, recurrent shoulder instability, systemic inflammatory disease, and previous shoulder surgery history were excluded. Coracohumeral distance (CHD), coracoid overlap (CO), lesser tuberosity index (LTI) and acromiohumeral interval (AHI) were measured bilaterally using CT scans. Based on arthroscopic findings, patients were included in either the SSC tear group (n = 72) or the control group (n = 141).

RESULTS

In the SSC tear group, the affected shoulder possessed a significantly smaller CHD [95% confidence interval (CI) 6.1-7.2 vs. 7.2-8.0 mm, p < 0.0001], larger LTI (95% CI 9.4-9.9 vs. 9.0-9.6 mm, p < 0.0001), and smaller AHI (95% CI 5.0-5.5 vs. 7.1-7.5 mm, p < 0.0001) than the contralateral normal shoulder. In the control group, there was no significant difference between bilateral CHD and CO, and the AHI bilateral discrepancy was less distinct. CO did not differ significantly in the bilateral comparison in either group. Among all evaluated parameters, bilateral CHD discrepancy was the best predictor of SSC tears, with an area under the curve (AUC) of 0.882. A cutoff value of 0.5 mm had a sensitivity of 76.4% and specificity of 99.3% for SSC tears.

CONCLUSION

The CHD values are significantly different between affected and contralateral shoulders in SSC tear patients. Bilateral CHD discrepancy is closely associated with subcoracoid impingement and SSC tears, and its presence warrants specific intraoperative SSC inspection.

LEVEL OF EVIDENCE

Level II.

A lower critical coracoid process angle is associated with type-B osteoarthritis: a radiological study of normal and diseased shoulders

Background

Degenerative rotator cuff tears and osteoarthritis (OA) are associated with differences in coronal plane scapular morphology, with particular focus on the effect of the critical shoulder angle (CSA) on shoulder biomechanics. The effect, if any, of axial plane scapular morphology is less well established. We have noticed wide disparity of axial coracoid tip position in relation to the face of the glenoid and sought to investigate the significance of this through measurement of the critical coracoid process angle (CCPA), which incorporates coracoid tip position and glenoid version.

Methods

CCPA, CSA, and glenoid retroversion were measured by three independent reviewers from the cross-sectional two-dimensional computed tomography (CT) and magnetic resonance imaging of 160 patients in four equal and matched case-control groups: (1) a control group of patients with a radiologically normal shoulder and no history of shoulder symptoms who had a CT thorax for another reason, (2) patients with primary OA with Walch type-A glenoid wear pattern on CT scan, (3) patients with type-B glenoid primary OA, and (4) patients with magnetic resonance imaging–proven atraumatic tears of the posterosuperior rotator cuff.

Results

Interobserver agreement was excellent for all measured parameters. The median CCPA was significantly lower in the type-B OA group (9.3˚) than that in controls (18.7˚), but not significantly different in the other study groups. There was a trend toward greater glenoid retroversion in the type-B OA group, but receiver operating characteristic curve analysis demonstrated the CCPA to be by far the most powerful discriminator for type-B OA. The optimal cutoff value was calculated for the CCPA at 14.3˚ with a sensitivity of 93% and specificity of 90% for type-B OA. Compared with controls, the CSA was significantly higher in the rotator cuff tear group and lower in both OA groups, but did not differentiate between type-A and type-B OA.

Conclusion

Combined with a lower CSA, a lower CCPA (<14.3˚) is strongly predictive of type-B glenoid OA. The authors propose a simple model of pectoralis major biomechanics to explain the effect of this axial plane anatomical variation, which requires further investigation.

Single-Portal, Single-Anchor Repair of a Superior Third Subscapularis Tear Using a Self-Punching Knotless Soft Suture Anchor

Numerous techniques exist for arthroscopic subscapularis repair with varying degrees of complexity based on tear morphology, all of which have established satisfactory outcomes in function and patient satisfaction. Arthroscopic subscapularis repair can require several working portals and suture anchors, increasing both technical complexity and operative time. This Technical Note describes an arthroscopic repair of a superior one-third subscapularis tear using a self-punching knotless soft suture anchor through a single anterior working portal. Thus, we offer a unique approach to arthroscopic repair of superior one-third subscapularis tears that is time-saving, reproducible, and highly efficient while minimizing iatrogenic damage and postoperative complications.

Atrophy patterns in isolated subscapularis lesions

BACKGROUND

While supraspinatus atrophy can be described according to the system of Zanetti or Thomazeau there is still a lack of characterization of isolated subscapularis muscle atrophy. The aim of this study was to describe patterns of muscle atrophy following repair of isolated subscapularis (SSC) tendon.

METHODS

Forty-nine control shoulder MRI scans, without rotator cuff pathology, atrophy or fatty infiltration, were prospectively evaluated and subscapularis diameters as well as cross sectional areas (complete and upper half) were assessed in a standardized oblique sagittal plane. Calculation of the ratio between the upper half of the cross sectional area (CSA) and the total CSA was performed. Eleven MRI scans of patients with subscapularis atrophy following isolated subscapularis tendon tears were analysed and cross sectional area ratio (upper half /total) determined. To guarantee reliable measurement of the CSA and its ratio, bony landmarks were also defined. All parameters were statistically compared for inter-rater reliability, reproducibility and capacity to quantify subscapularis atrophy.

RESULTS

The mean age in the control group was 49.7 years (± 15.0). The mean cross sectional area (CSA) was 2367.0 mm² (± 741.4) for the complete subscapularis muscle and 1048.2 mm² (± 313.3) for the upper half, giving a mean ratio of 0.446 (± 0.046). In the subscapularis repair group the mean age was 56.7 years (± 9.3). With a mean cross sectional area of 1554.7 mm² (± 419.9) for the complete and of 422.9 mm² (± 173.6) for the upper half of the subscapularis muscle, giving a mean CSA ratio of 0.269 (± 0.065) which was seen to be significantly lower than that of the control group (p < 0.05).

CONCLUSION

Analysis of typical atrophy patterns of the subscapularis muscle demonstrates that the CSA ratio represents a reliable and reproducible assessment tool in quantifying subscapularis atrophy. We propose the classification of subscapularis atrophy as Stage I (mild atrophy) in case of reduction of the cross sectional area ratio < 0.4, Stage II (moderate atrophy) in case of < 0.35 and Stage III (severe atrophy) if < 0.3.

Less than 9.5-mm coracohumeral distance on axial magnetic resonance imaging scans predicts for subscapularis tear

Background

Diagnosis of subscapularis (SSC) tendon lesions on magnetic resonance imaging (MRI) can be challenging. A small coracohumeral distance (CHD) has been associated with SSC tears. This study was designed to define a specific threshold value for CHD to predict SSC tears on axial MRI scans.

Methods

This retrospective study included 172 shoulders of 168 patients who underwent arthroscopic surgery for rotator cuff tear or glenohumeral instability. Diagnostic arthroscopy confirmed an SSC tear in 62 cases (36.0%, test group a), rotator cuff tear tears other than SSC in 71 cases (41.3%, control group b) and glenohumeral instability without any rotator cuff tear in 39 cases (22.7%, zero-sample group c). All patients had a preoperative MRI of the shoulder (1.5T or 3T). Minimum CHD was measured on axial fat-suppressed proton density-, T2-, or T1-weigthed sequences. Receiver operating characteristics analysis was used to determine the threshold value for CHD, and sensitivity and specificity were calculated.

Results

CHD measurement had a good interobserver reliability (Intraclass correlation coefficient 0.799). Mean CHD was highly significantly (P < .001) less for test group a (mean 7.3 mm, standard deviation ± 2.2) compared with control group b (mean 11.1 mm, standard deviation ± 2.3) or zero-sample group c (mean 13.6 mm, standard deviation ± 2.9). A threshold value of CHD <9.5 mm had a sensitivity of 83.6% and a specificity of 83.9% to predict SSC tears.

Conclusion

A CHD <9.5 mm on MRI is predictive of SSC lesions and a valuable tool to diagnose SSC tears.

Measurement of the coracohumeral distance on magnetic resonance imaging in a large patient cohort

BACKGROUND

Coracoid impingement syndrome is an increasingly recognized etiology of anterior shoulder pain. Numerus studies have documented the coracohumeral distance (CHD) as a primary or secondary measurement in symptomatic individuals, but there lacks an evaluation of CHD in a large cohort of asymptomatic individuals. The purpose of this study was to quantify a normative distribution of the CHD in a large cohort of healthy, asymptomatic subjects with no history of impingement or shoulder instability.

METHODS

Incoming first-year students in the United States Military Academy were offered enrollment in this study as part of a prospective cohort to assess the normal anatomic relationships of the shoulder girdle. Magnetic resonance images were obtained, and a board-certified, fellowship-trained musculoskeletal radiologist performed measurements of the smallest distance from the coracoid to the humeral head on axial images.

RESULTS

Magnetic resonance images of 714 subjects were available for analysis, including 630 males and 84 females, with a total of 1120 individual shoulders with images of adequate quality. The mean CHD for all shoulders imaged was 13.7 mm. The mean CHD in male shoulders was 13.8 mm, and in female subjects the average was 12.4 mm.

CONCLUSIONS

This study is the largest of its kind to evaluate the CHD in asymptomatic, healthy shoulders to date and demonstrates a mean CHD of 13.7 mm for all subjects. This information can help to standardize "normal" ranges and act as a comparison for future work, when taken in the context of age and imaging in neutral rotation.

Diagnosis and Management of Subcoracoid Impingement

Impingement of the subcoracoid space is a poorly understood pathologic cause of anterior shoulder pain. Because of its relative rarity in isolation and nonspecific presentation, diagnosis and management are often challenging for orthopaedic surgeons and their patients. Stenosis of the subcoracoid space between the lesser tuberosity and the coracoid process <6 mm can lead to anterior shoulder pain and associated rotator cuff and biceps pathology. Multiple imaging modalities are available to assess narrowing of the coracohumeral interval, each with its strengths and limitations. If the patient can be accurately diagnosed with subcoracoid impingement, both conservative and surgical management options are available. Despite earlier case series demonstrating promising results with arthroscopic treatment, comparative studies have yet to support these initial claims.

Medium- to long-term clinical and functional outcomes of isolated and combined subscapularis tears repaired arthroscopically

INTRODUCTION

The purpose of this study was twofold. First, the efficacy of arthroscopic repair in patients with full thickness, isolated subscapularis tendon tears (I-STTs) or combined subscapularis tendon tears (C-STTs) involving the rotator cuff tendons was evaluated. Second, the outcomes between these two groups were compared. The influence of age and gender on the cohort clinical outcomes was also analysed. Our hypothesis was that satisfactory functional results could be obtained arthroscopically in both groups without any influence of age or gender.

MATERIAL AND METHODS

Seventy-nine patients were enrolled: 15 with I-STTs and 64 with C-STTs. The clinical outcomes were assessed using Constant and Disabilities of the Arm, Shoulder and Hand (DASH) scores, Numeric Rating Scale (NRS) for pain and Visual Analogue Scale (VAS) for satisfaction. The subscapularis strength was assessed using a comparative dynamometric bear-hug test. Group outcomes were compared, including statistical analysis.

RESULTS

For each group, there were no differences regarding the subscapularis strength of the operated and non-operated shoulders. A comparison of the post- with the pre-operative outcomes showed an increase in the Constant score and a decrease in the NRS. Comparing the two groups, we found no difference in strength of the operated and non-operated shoulders, but a significant difference in relation to pre-operative Constant score and pre-operative NRS. Age was negatively correlated with both pre-operative and post-operative Constant scores. No association was found between gender and the outcomes, although the DASH score was higher in women.

CONCLUSIONS

Arthroscopic repair of STTs provided functional restoration, pain relief and patient satisfaction in both groups. Age and gender did not affect the clinical outcomes achieved by arthroscopic STT repair.

The anterior translation of the humeral head leads to a decrease in the coracohumeral distance in subscapularis tear

A total of 297 patients who classified as subscapularis (SC) tears through arthroscopic evaluation were retrospectively enrolled, and Fifty-seven patients with impingement syndrome were also enrolled as the control group for normal-population comparison. The coracohumeral distance (CHD) and humeral head anterior translation (HHAT) were measured on magnetic resonance imaging. Our study demonstrated that the anterior translation of the humeral head is related with a decrease in the coracohumeral distance in subscapularis tear. Although, correlation between radiologic parameters (coracohumeral distance and anterior translation of the humeral head) and severity of subscapularis tear was note detected.

Level of evidence

Level IV, retrospective study.

Thinking outside the glenohumeral box: Hierarchical shape variation of the periarticular anatomy of the scapula using statistical shape modeling

Variation in the shape of the glenoid and periarticular anatomy of the scapula has been associated with shoulder pathology. The goal of this study was to identify the modes of shape variation of periarticular scapular anatomy in relation to the glenoid in nonpathologic shoulders. Computed tomography scans of 31 cadaveric scapulae, verified to be free of pathology, were three-dimensionally reconstructed. Statistical shape modeling and principal component analysis identified the modes of shape variation across the population. Corresponding linear and angular measurements quantified the morphometric variance identified by the modes. Linear measures were normalized to the radius of the inferior glenoid to account for differences in the scaling of the bones. Five modes captured 89.7% of total shape variation of the glenoid and periarticular anatomy. Apart from size differences (mode 1: 33.0%), acromial anatomy accounted for the largest variation (mode 2: 32.0%). Further modes described variation in glenoid inclination (mode 3: 11.8%), coracoid orientation and size (mode 4: 9.0%), and variation in coracoacromial (CA) morphology (mode 5: 3.1%). The average scapula had a mean acromial tilt of 49 ± 7°, scapular spine angle of 61 ± 6°, the glenoid inclination of 84 ± 4°, coracoid deviation angle of 26 ± 4°, coracoid length of 3.7 ± 0.3 glenoid radii, and a CA base length of 5.6 ± 0.5 radii. In this study, the identified shape modes explain almost all of the variance in scapular anatomy. The acromion exhibited the highest variance of all periarticular anatomic structures of the scapula in relation to the glenoid, which may play a role in many shoulder pathologies.

Do coracohumeral interval and glenoid version play a role in subscapularis tears?

Purpose

To study the effect of the coracohumeral interval and orientation of the glenoid for causation of subscapularis tears and literature review for the need of coracoplasty.

Methods

This is a retrospective cohort study of patients who underwent arthroscopic shoulder surgery from January 2013 to December 2017. The coracohumeral interval and orientation of the glenoid in patients with arthroscopically diagnosed subscapularis tears (group A, n = 40) were compared with 2 control groups (group B, n = 38 [intact subscapularis with supraspinatus and infraspinatus cuff tears] and group C, n = 39 [intact rotator cuff]). Group A1 (n = 23) consisted of the isolated subscapularis and combined subscapularis + supraspinatus tears, and group A2 (n = 17) all the 3 rotator cuff tears. The measurements were made on preoperative axial magnetic resonance imaging. Statistical analysis was performed to compare the groups.

Results

The mean coracohumeral interval was 8.81 ± 2.69 mm in group A and 10.62 ± 2.21 and 10.39 ± 2.59 mm in control groups B and C, respectively; this difference was statistically significant (P = .002 and .01, respectively). The mean glenoid version in patients with subscapularis tears was -3.7°, whereas the mean version in patients with intact cuff was -3.4°, and this difference was not statistically significant (P = .74). The mean glenoid version was -4.69° ± 4.22° in group A1 and -3.28° ± 4.04° in group B, with no statistically significant difference (P = .07).

Conclusion

The coracohumeral interval was significantly decreased in patients with subscapularis tears. The glenoid was retroverted in the subscapularis group but was not statistically significant.

Ten-year clinical and magnetic resonance imaging evaluation after repair of isolated subscapularis tears

Hypothesis

The purpose was to evaluate long-term clinical outcomes and tendon structural integrity after repair of isolated subscapularis (SSC) tendon tears.

Methods

Sixty-one patients who underwent repair of isolated SSC tears were evaluated. The mean interval from symptom onset to surgery was 5.3 months. Shoulder function was investigated using the Constant score and Subjective Shoulder Value (SSV). Structural integrity of the repair and quality of the repaired tendon were assessed using magnetic resonance imaging. Independent preoperative factors affecting clinical outcomes, including patient sex, age, smoking habits, injections, dominant shoulder, profession, and tear onset (chronic vs. traumatic), were evaluated.

Results

A total of 35 patients (9 women and 26 men; mean age, 54 years) were included at the final 10-year follow-up because 21 patients were lost to follow-up and 5 underwent reoperations. The mean Constant score improved from 55.1 points preoperatively to 75.4 points postoperatively (P = .001). The postoperative SSV was 80.9, and the retear rate was 12.9%. Postoperative fatty infiltration increased in 26% of the patients with grades 3-4, but it was not related to lower clinical outcomes. Multivariable regression analysis revealed no correlation among the preoperative factors, including sex, age, smoking habits, injections, dominant shoulder, profession, and tear onset, and the postoperative Constant score, SSV, and tendon healing.

Conclusion

At a mean of 10 years after repair of isolated SSC tears, clinical results were satisfactory and functional improvement was maintained in the long term. Severe fatty infiltration increased with time, but it was not related to clinical outcomes and the retear rate.

Coracoid morphology is not associated with subscapularis tears

BACKGROUND

The observation of the roller-wringer effect fueled the idea that coracoid morphology is related to subscapularis pathology. We aimed to examine this relationship, specifically focusing on how the coracohumeral distance (CHD) and 2 new metrics of coracoid morphology relate to subscapularis tears.

METHODS

In this retrospective study, we identified consecutive patients 45 years or older who underwent shoulder arthroscopy for any indication. We blindly reviewed preoperative magnetic resonance imaging studies of each patient, measuring the CHD, lateral extent (LE), and caudal extent (CE) of the coracoid process. Patients' subscapularis condition was assessed via operative reports; stratified according to Lafosse grade criteria; and compared for differences in the CHD, LE, and CE by 1-way analysis of variance and 2-tailed t tests.

RESULTS

The study included 201 patients. Of these, 112 had no evidence of subscapularis injury, whereas Lafosse grade I injuries were identified in 52 patients; grade II, in 19; and grades III-V, in 18. The CHD, LE, and CE were not correlated with subscapularis injury (CHD, P = .36; LE, P = .36; and CE, P = .13).

CONCLUSIONS

We found no correlation between subscapularis injury and the CHD, LE, and CE. These findings support the idea that coracoid morphology may not be a cause of subscapularis pathology and suggest that coracoplasty may not be necessary prophylactically or as part of subscapularis repair.

Comparison of Functional and Radiological Outcomes of Tears Involving the Subscapularis: Isolated Subscapularis Versus Combined Anterosuperior Rotator Cuff Tears

Background:

Few studies have compared the clinical and radiological characteristics and outcomes in isolated subscapularis (SSC) and combined anterosuperior (AS) rotator cuff tears (RCTs). Furthermore, risk factors for retear after SSC repair and the effect of preoperative fatty degeneration require further evaluation.

Purpose:

To compare the functional and radiological outcomes of isolated SSC with combined AS RCTs after arthroscopic repair and to determine the risk factors for SSC retear in these 2 groups.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Data from 30 patients in the isolated SSC group were compared with data from 110 patients in the combined AS group. All patients underwent primary arthroscopic rotator cuff repair between 2010 and 2016. Clinical outcomes were assessed through use of the visual analog scale for pain, American Shoulder and Elbow Surgeons score, and Simple Shoulder Test at a mean follow-up of 26.7 months (range, 24-96 months). SSC tendon integrity was examined via magnetic resonance imaging, computed tomography arthrogram, or ultrasonography at least 1 year after surgery.

Results:

The isolated SSC group had a greater proportion of males and the patients were younger compared with the combined AS group (both P < .050). The incidence of trauma was high but not significantly different between groups (56.7% vs 40.9%; P = .180). Clinical outcome measures and radiological outcomes in terms of retear were not statistically different between both groups (16.7% vs 8/5%; P = .337). The optimal cutoff values for the risk of SSC tendon retear in both groups were 19-mm retraction and 16-mm superoinferior dimension (P = .048). Unfavorable preoperative fatty degeneration of the SSC muscle (grades 3 and 4) was a significant risk factor for retear (odds ratio, 9.8; P < .001).

Conclusion:

Isolated SSC and combined AS RCTs were comparable except for patient age and sex; both had a high incidence of traumatic history. The current data suggest that the risk factors for retear after SSC repair in RCTs involving the SSC were tear size greater than 19 mm of retraction and unfavorable fatty degeneration (grade 3 or higher) of the SSC muscle.

New predictors for subscapularis tear: Coraco-lesser tuberosity angle, lesser tuberosity angle, and lesser tuberosity height

BACKGROUND

The pathogenesis of degenerative subscapularis (SC) tear is not clear, several mechanisms are involved: intrinsic tendon degeneration or subcoracoid impingement. The aim of this study was to propose new radiographic markers, the coraco-lesser tuberosity angle (CLA), lesser tuberosity angle (LTA) and lesser tuberosity height (LTH). The hypothesis was that higher values of CLA, LTA, and LTH would be associated with a higher likelihood in detecting a SC tear.

METHOD

A total of 114 patients who classified as SC tears through arthroscopic evaluation were retrospectively enrolled in the study from 2016 to 2018. Fifty-seven patients with impingement syndrome were also enrolled as the control group for normal-population comparison. The CLA was measured on an anteroposterior shoulder x-ray image with the arm in neutral rotation, the LTA and LTH were measured on magnetic resonance imaging. Multivariable analyses were used to clarify the potential risks for SC tears. All measurements were calculated by two shoulder surgeons independently measured at 2 different times, 1 month apart.

RESULTS

The intra- and inter-observer reliabilities for radiologic measurements and the interobserver reliability of SC tear classification were almost perfect. The mean CLA value of SC tear group (41.4±4.2°) was significantly larger than that of the control group (38.7±4.0°, p<0.001). The mean LTA value of SC tear group (33.4±4.3°) was significantly larger than that of the control group (31.0±3.9°, p=0.001). Mean LTH value was 9.5±1.9mm in patients and 8.9±1.5mm for controls, there was no statistically significant difference (p=0.054). Multivariable analysis showed that larger CLAs significantly increased the risk of SC tears, with odds ratios of 1.17 per degree. Moreover, larger LTAs also significantly increased the risk of SC tears, with odds ratios of 1.14 per degree.

CONCLUSION

Our findings confirmed associations between new predictors (CLA and LTA) and SC tears. CLA and LTA values were greater in patients with SC tears than in controls, suggesting that they may be independent risk factors for SC tear onset.

LEVEL OF EVIDENCE

IV, retrospective study.

Magnetic resonance imaging based coracoid morphology and its associations with subscapularis tears: a new index

BACKGROUND

We aimed to assess the validity of magnetic resonance imaging (MRI) in assessing the subcorocoid space and determine the validity of novel sagittal plane subcorocoid space measurements.

METHODS

We assessed 33 arthroscopically proven subscapularis tears with MRIs compared to 33 (instability) controls with normal subscapularis tendons. Three examiners analyzed MRIs for seven static indices of corocoid morphology, in axial and sagittal planes. We explored reviewer variation using intraclass correlation coefficients (ICC) and differences between the two groups was explored using t-tests.

RESULTS

Groups were similar in characteristics but different in age (cases = 53, controls = 23). ICC showed good (2/7) or excellent (5/7) reliability. Small differences(<1.6 mm) were identified between subscapularis tears and controls in coraco-humeral distance, in axial (p = 0.092) and sagittal planes (p = 0.045). There were statistically significant differences between groups when analyzing the angular projection of the coracoid from the glenoid, in both sagittal (p < 0.0001) and axial planes (p = 0.045).

CONCLUSIONS

Acute inferior angulation of the corocoid in the sagittal plane may be associated with subscapularis tears. Static indices are measured within the scapula and not affected by arm position. MRI reliably provided a platform to assess the coracoid. Based on this, we currently consider corocoplasty in patients with subscapularis tears and a sagittal coroco-glenoid angle <60^o to reduce potential impingement.

Radiological Variabilities in Subcoracoid Impingement: Coracoid Morphology, Coracohumeral Distance, Coracoglenoid Angle, and Coracohumeral Angle

BACKGROUND The aim of this study was to investigate the effects of coracoid morphology, coracohumeral distance, coracoglenoid angle, and coracohumeral angle variabilities on subcoracoid impingement development using magnetic resonance imaging (MRI). MATERIAL AND METHODS A total of 200 patients (87 males with mean age of 51.1±15.2 years and 113 females with mean age of 52.6±10.7 years) undergoing shoulder MRI were included in this retrospective study. All MRI studies were performed with standard positioning. Coracoid morphology and subscapularis tendon were evaluated. Coracohumeral distance, coracoglenoid angle and coracohumeral angle were measured in all subjects. One-way ANOVA was used to assess the difference between the groups. For binary comparisons, Tukey post hoc analysis was done. Pearson correlation analysis was performed between variables. RESULTS Type C coracoid was more frequent in the tendinosis and tendon tear groups. There was a significant difference between type C coracoid and the other coracoid types for coracohumeral distance values (P=0.016). There was a statistically significant decrease in coracoglenoid angle values and coracohumeral distance in patients with subscapularis tendon pathologies (P=0.000). A statistically insignificant increase in coracohumeral angle values was found in the subscapularis tendon pathologies. There was a positive correlation between coracohumeral distance and coracoglenoid angle (R=0.749 P=0.000). There was a negative correlation between coracohumeral distance and coracohumeral angle (R=-0.668 P=0.000) and between coracoglenoid angle and coracohumeral angle (R=-0.605 P=0.000). CONCLUSIONS In subscapularis tendon pathologies, decrease in coracohumeral distance and coracoglenoid angle was observed. A new approach uses coracohumeral angle to evaluate subcoracoid impingement. A statistically insignificant increase in coracohumeral angle was noted.

Concomitant coracoplasty during arthroscopic subscapularis repair does not yield better clinical outcomes and structural integrity

PURPOSE

Few studies have examined whether concomitant coracoplasty is necessary to improve clinical and radiological outcomes after arthroscopic subscapularis repair. The purpose of this study was to compare clinical outcomes and structural integrity after arthroscopic repair of isolated subscapularis full-thickness tear, either with or without concomitant coracoplasty.

METHODS

This study included 62 patients who underwent arthroscopic subscapularis repair either with coracoplasty (Group A, 35 patients) or without coracoplasty (Group B, 27 patients). Preoperative and postoperative visual analog scale pain scores, subjective shoulder values, University of California at Los Angeles shoulder scores, American Shoulder and Elbow Surgeon scores, subscapularis strength, and shoulder active range of motion (ROM) were assessed. Postoperative magnetic resonance arthrography (MRA) or computed tomographic arthrography (CTA) was performed 6 months postoperatively for structural integrity assessment.

RESULTS

At 2-year follow-up, all functional scores and ROM improved significantly in both groups compared with preoperative values (p < 0.001). However, none of these values differed significantly between groups. On follow-up MRA or CTA images, although postoperative coracohumeral distance was significantly greater in Group A (8.4 mm ± 2.3 mm versus 7.0 mm ± 2.0 mm) (p = 0.018), the re-tear rates were not significantly different between groups (5/35 (14%) in Group A and 4/27 (15%) in Group B).

CONCLUSIONS

For isolated subscapularis full-thickness tears, concomitant coracoplasty with arthroscopic repair did not produce better clinical outcomes or structural integrity than repair without coracoplasty. This suggests that concomitant coracoplasty may not be imperative during arthroscopic repair of isolated subscapularis full-thickness tears.

LEVEL OF EVIDENCE

III.

The outcomes and affecting factors after arthroscopic isolated subscapularis tendon repair

BACKGROUND

This study evaluated clinical outcomes for isolated subscapularis tendon tears treated by arthroscopic repair, the factors affecting clinical outcomes, and changes in tendon structural integrity using magnetic resonance imaging.

METHODS

Between 2005 and 2013, 45 patients with isolated subscapularis tendon tears were enrolled from two institutions. Clinical outcomes were assessed using the pain visual analog scale, American Shoulder and Elbow Surgeons, and Simple Shoulder Test scores. We evaluated factors affecting clinical outcomes: trauma history, tear classification, sex, age, symptom duration, preoperative fatty infiltration grade, cross-sectional area (CSA), cranial-transversal diameter, and caudal-transversal diameter. Subscapularis tendon integrity and fatty infiltration grade were evaluated using magnetic resonance imaging.

RESULTS

No complications occurred except for tendon rerupture in 1 patient. No significant changes in tendon structural integrity occurred except for those related to CSA. Tendon structural integrity was significantly different between tears less than one-fourth of the entire subscapularis tendon and those exceeding one-fourth. However, there were no statistically significant differences in clinical outcomes between the 2 types of tear. Age was significantly associated with clinical outcomes, including Constant, American Shoulder and Elbow Surgeons, and Simple Shoulder Test scores. Men experienced better outcomes than women in Constant and Simple Shoulder Test scores. As the postoperative period progressed, the difference in CSA, cranial-transversal diameter, and caudal-transversal diameter decreased to the point of no statistical significance.

CONCLUSION

Arthroscopic repair of isolated subscapularis tear provided significant functional improvements with a low rerupture rate. Age was significantly associated with clinical results.

Anatomic Study of Subcoracoid Morphology in 418 Shoulders: Potential Implications for Subcoracoid Impingement

Background:

Subcoracoid impingement has been implicated as a cause of anterior shoulder pain and subscapularis tendon tears.

Purpose/Hypothesis:

The purpose of this study was to evaluate the bony anatomy of the coracoid process and the subcoracoid space. We hypothesized that age-related changes that may contribute to subcoracoid impingement occur in the subcoracoid space.

Study Design:

Descriptive laboratory study.

Methods:

In total, 418 skeletal shoulder specimens were included in this study. We utilized 214 shoulders from a young cohort (25-35 years of age) and 204 shoulders from an older cohort (>55 years of age) for comparison. We evaluated several morphological characteristics of the coracoid process and the subcoracoid space: coracoid width, coracoid shape, coracoid thickness, and subcoracoid distance. Each coracoid was observed for the presence of spurring or other morphological changes.

Results:

The mean anteroposterior (AP) thickness of the coracoid tip was 7.9 and 9.4 mm in our young female and male cohorts, respectively, while the mean AP thickness was 8.1 and 9.7 mm in our older female and male cohorts, respectively. The coracoid tip was hooked in 31 of 108 young female shoulders compared with 55 of 102 older female shoulders, and the coracoid tip was hooked in 25 of 106 young male shoulders compared with 45 of 102 older male shoulders. The mean subcoracoid distance in neutral rotation was 14.8 and 12.5 mm in young and older female shoulders, respectively, while the mean subcoracoid distance in internal rotation in these same cohorts was 8.7 and 7.0 mm, respectively. The mean subcoracoid distance in neutral rotation was 14.8 and 13.3 mm in young and older male shoulders, respectively, while the mean subcoracoid distance in internal rotation was 8.6 and 8.1 mm in young and older male shoulders, respectively.

Conclusion:

The principal findings of our study demonstrate that anatomic changes implicated in subcoracoid impingement may be developmental and worsen with age. The subcoracoid space was narrower in our older cohort of shoulders. Additionally, these older shoulders also had a greater AP width and a more hooked coracoid compared with young shoulders.

Clinical Relevance:

Narrowing of the subcoracoid space has been shown to be implicated as a cause of anterior shoulder pain and subscapularis tendon tears. This is the first study to show that the morphological changes implicated in subcoracoid impingement become more prevalent with age. This may help to explain the increasing prevalence of subscapularis tendon tears in older patients. Furthermore, subcoracoid decompression may be seen as an option for older patients with anterior shoulder pain and subscapularis tendon tears.

Comparison of Clinical and Structural Outcomes by Subscapularis Tendon Status in Massive Rotator Cuff Tear

BACKGROUND

The subscapularis tendon is essential in maintaining normal glenohumeral biomechanics. However, few studies have addressed the outcomes of tears extending to the subscapularis tendon in massive rotator cuff tears.

PURPOSE

To assess the clinical and structural outcomes of arthroscopic repair of massive rotator cuff tears involving the subscapularis.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Between January 2010 and January 2014, 122 consecutive patients with massive rotator cuff tear underwent arthroscopic rotator cuff repair. Overall, 122 patients were enrolled (mean age, 66 years; mean follow-up period, 39.5 months). Patients were categorized into 3 groups based on subscapularis tendon status: intact subscapularis tendon (I group; n = 45), tear involving less than the superior one-third (P group; n = 35), and tear involving more than one-third of the subscapularis tendon (C group; n = 42). All rotator cuff tears were repaired; however, subscapularis tendon tears involving less than the superior one-third in P group were only debrided. Pain visual analog scale, Constant, and American Shoulder and Elbow Surgeons scores and passive range of motion were measured preoperatively and at the final follow-up. Rotator cuff integrity, global fatty degeneration index, and occupation ratio were determined via magnetic resonance imaging preoperatively and 6 months postoperatively.

RESULTS

We identified 37 retears (31.1%) based on postoperative magnetic resonance imaging evaluation. Retear rate in patients in the C group (47.6%) was higher than that in the I group (22.9%) or P group (20.0%) ( P = .011). Retear subclassification based on the involved tendons showed that subsequent subscapularis tendon retears were noted in only the C group. The improvement in clinical scores after repair was statistically significant in all groups but not different among the groups. Between-group comparison showed significant differences in preoperative external rotation ( P = .021). However, no statistically significant difference was found in any shoulder range of motion measurements after surgery.

CONCLUSION

Arthroscopic repair of massive tears results in substantial improvements in shoulder function, despite the presence of combined subscapularis tears. However, this study showed a high failure rate of massive posterosuperior rotator cuff tear repair extending more than one-third of the subscapularis tendon. When combined subscapularis tendon tear was less than the superior one-third of the subscapularis tendon, arthroscopic debridement was a reasonable treatment method where comparable clinical and anatomic outcomes could be expected.

Redefining anterior shoulder impingement: a literature review

Many different types of impingements have been described in the shoulder. Inasmuch as the term 'shoulder impingement' usually refers to subacromial impingement, anterior impingement usually refers to subcoracoid impingement. However, there are many different subtypes of anterior impingements in the shoulder, and awareness of their existence is critical as they vary in their nature and treatment. Recent advances in biomechanical research and arthroscopic exploration of the anterior structures of the shoulder have brought new insights on the various potential impingements, warranting a revision and update of the current definitions of anterior shoulder impingement. The purpose of this article is to propose a comprehensive review and classification of all different subtypes of anterior impingement in the shoulder, including newly described entities.

Subscapularis Tendon Slip Number and Coracoid Overlap Are More Related Parameters for Subcoracoid Impingement in Subscapularis Tears: A Magnetic Resonance Imaging Comparison Study

PURPOSE

To investigate the effects of the subscapularis tendon slip number (STSN) and coracoid morphology by magnetic resonance imaging in patients with and without subscapularis tears.

METHODS

Patients who underwent shoulder arthroscopy between February 2004 and June 2015 were re-evaluated. Those with a subscapularis tear (study group) and those with other pathologies (control group) were compared with each other. Magnetic resonance imaging scans and surgery videos of the patients were reassessed. Transverse and sagittal coracohumeral distance (CHD), coracoid overlap (CO), coraco-coracoid base angle (CBA), coracoglenoid distance (CGD), and STSN were measured.

RESULTS

The study and control groups comprised 141 and 78 patients, respectively. The mean age was 57.01 ± 10.95 (similar in both the groups). The mean transverse CHD and sagittal CHD were not different between the groups and also between female and male patients. For the study and control groups, the mean CBA and CGD values were also similar. The mean CO was 24.01 ± 4.9 and 21.29 ± 4.58 for the study and control groups, respectively (P < .001). With the receiver operating characteristic curve of the CO, the sensitivity was 62% and the specificity was 64% at the cutoff value of 22.85 mm. The STSN was in the range between 1 and 6; the STSN was 3 or less in 61.5% of the study group and in 38.5% of the control group (P = .005).

CONCLUSIONS

The CO was the most valuable parameter predicting any potential subcoracoid impingement, and the STSN was inversely correlated with subscapularis tears. However, in predicting a potential subcoracoid impingement, the CHD measurements were not significant, as well the CGD and CBA.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Three-Dimensional Morphometric Analysis of the Coracohumeral Distance Using Magnetic Resonance Imaging

There have been no studies investigating three-dimensional (3D) alteration of the coracohumeral distance (CHD) associated with shoulder motion. The aim of this study was to investigate the change of 3D-CHD with the arm in flexion/internal rotation and horizontal adduction. Six intact shoulders of four healthy volunteers were obtained for this study. MRI was taken in four arm positions: with the arm in internal rotation at 0°, 45°, and 90° of flexion, and 90° of flexion with maximum horizontal adduction. Using a motion analysis system, 3D models of the coracoid process and proximal humerus were created from MRI data. The CHD among the four positions were compared, and the closest part of coracoid process to the proximal humerus was also assessed. 3D-CHD significantly decreased with the arm in 90° of flexion and in 90° of flexion with horizontal adduction comparing with that in 0° flexion (P<0.05). In all subjects, lateral part of the coracoid process was the closest to the proximal humerus in these positions. In vivo quasi-static motion analysis revealed that the 3D-CHD was narrower in the arm position of flexion with horizontal abduction than that in 0° flexion. The lateral part on the coracoid process should be considered to be closest to the proximal humerus during the motion.

Long-term Results After Arthroscopic Repair of Isolated Subscapularis Tears

BACKGROUND

Although some reports have presented short- to midterm results after arthroscopic repair of isolated subscapularis (SSC) tendon tears, long-term evaluation is still lacking.

HYPOTHESIS

Long-term results after arthroscopic repair of isolated SSC tears are comparable with the functional and radiological short- to midterm outcomes described in the literature.

STUDY DESIGN

Case series, Level of evidence, 4.

METHODS

This study assessed 17 patients (5 females and 12 males; mean age, 45.6 years) with isolated SSC tears (Fox and Romeo classification types 2-4) who underwent all-arthroscopic suture anchor repair. The mean interval from symptom onset to the time of surgery was 5.3 months in 16 patients (94.1%). One patient (5.9%) was symptomatic for a prolonged period (104 months) before surgery. All patients were assessed with a clinical examination preoperatively. SSC function was investigated using specific clinical tests and common scoring systems, including Constant, American Shoulder and Elbow Surgeons (ASES), Disabilities of the Arm, Shoulder and Hand (DASH), and Simple Shoulder Test (SST) scores. At follow-up, muscular strength was evaluated using an electronic force-measuring plate. Structural integrity of the repair was assessed using magnetic resonance imaging (MRI).

RESULTS

At a mean follow-up of 98.4 ± 19.9 months, the mean Constant score improved from 47.8 preoperatively to 74.2 postoperatively ( P = .001). Higher Constant ( P = .010) and ASES ( P = .001) scores were significantly associated with a shorter time from symptom onset to surgery. The size of the SSC lesion did not correlate with any clinical score outcome ( P = .476, .449, .985, and .823 for Constant, ASES, DASH, and SST scores, respectively). Three patients (17.6%) had persistent positive clinical test results (belly-press/lift-off). Compared with the uninjured contralateral side, SSC strength was significantly reduced in the belly-press position ( P = .031), although active internal ( P = .085) and external ( P = .093) rotation was not affected. In 1 patient, a rerupture was detected by MRI. Six patients had cranial SSC atrophy. Overall, 88.2% of patients were "very satisfied" or "satisfied" with their results.

CONCLUSION

Arthroscopic repair of isolated SSC tears results in significant clinical improvements and enduring tendon integrity, although SSC strength remains reduced in the long term. Early surgical treatment seems to be a relevant factor allowing good shoulder function.

Multi-modal imaging of the subscapularis muscle

Abstract

The subscapularis (SSC) muscle is the most powerful of the rotator cuff muscles, and plays an important role in shoulder motion and stabilization. SSC tendon tear is quite uncommon, compared to the supraspinatus (SSP) tendon, and, most of the time, part of a large rupture of the rotator cuff. Various complementary imaging techniques can be used to obtain an accurate diagnosis of SSC tendon lesions, as well as their extension and muscular impact. Pre-operative diagnosis by imaging is a key issue, since a lesion of the SSC tendon impacts on treatment, surgical approach, and post-operative functional prognosis of rotator cuff injuries. Radiologists should be aware of the SSC anatomy, variability in radiological presentation of muscle or tendon injury, and particular mechanisms that may lead to a SSC injury, such as coracoid impingement.

Teaching Points

• Isolated subscapularis (SSC) tendon tears are uncommon.

• Classically, partial thickness SSC tendon tears start superomedially and progress inferolaterally.

• Long head of biceps tendon medial dislocation can indirectly signify SSC tendon tears.

• SSC tendon injury is associated with anterior shoulder instability.

• Dynamic ultrasound study of the SSC helps to diagnose coracoid impingement.

Measurement of Coracohumeral Distance in 3 Shoulder Positions Using Dynamic Ultrasonography: Correlation With Subscapularis Tear

PURPOSE

To detect differences between the values of dynamic coracohumeral distance (CHD) measured using ultrasonography (USG) in different shoulder rotations and to investigate its correlation with subscapularis tear.

METHODS

We prospectively enrolled consecutive patients (n = 168) who were scheduled to have arthroscopic rotator cuff repair. Patients with a history of previous shoulder surgery or shoulder fracture and patients with external rotation less than 30° were excluded from the study. Dynamic CHD was measured using USG in 3 different shoulder positions: external rotation, neutral and internal rotation. We evaluated the intrarater reliability with 3 times repetition of measurement. Patients were divided into 1 of 3 groups according to arthroscopic findings: intact subscapularis, partial-thickness tear, and full-thickness tear of the subscapularis. The control group (n = 23) included patients without rotator cuff tears from the outpatient clinic. Subgroup analysis-according to the presence of dynamic subcoracoid stenosis, defined as a CHD less than 6 mm measured in internal rotation-was performed to find the clinical effect of dynamic subcoracoid stenosis.

RESULTS

A partial-thickness tear of the subscapularis tendon was present in 60 patients (35.7%) and a full-thickness tear in 26 patients (15.4%) among 168 patients. The CHD was maximum in external rotation and the narrowest in internal rotation. There were no statistical differences in the CHDs between groups with different subscapularis tear status. According to the presence of dynamic subcoracoid stenosis, patients with dynamic subcoracoid stenosis had a significantly higher incidence of partial-thickness subscapularis tear than those without stenosis (P = .022).

CONCLUSIONS

The CHD values were narrowest in shoulder internal rotation, which is thought to be the pathogenic position. We could not confirm the correlation between CHD and subscapularis tear. However, patients who have dynamic subcoracoid stenosis had significantly higher incidence of subscapularis tear than others without dynamic stenosis.

LEVEL OF EVIDENCE

Level II, prospective prognostic cohort study.

Coracoid Process: The Lighthouse of the Shoulder

The coracoid process is a hook-shaped bone structure projecting anterolaterally from the superior aspect of the scapular neck. Surgeons often refer to the coracoid process as the "lighthouse of the shoulder" given its proximity to major neurovascular structures such as the brachial plexus and the axillary artery and vein, its role in guiding surgical approaches, and its utility as a landmark for other important structures in the shoulder. The coracoid also serves as a critical anchor for many tendinous and ligamentous attachments. These include the tendons of the pectoralis minor, coracobrachialis, and short head of the biceps brachii muscles, and the coracoclavicular, coracohumeral, coracoacromial, and transverse scapular ligaments. Consequently, the coracoid and its associated structures are linked to numerous shoulder pathologic conditions. This article will detail the anatomy of the coracoid and its associated structures and review the clinical and radiologic findings of corresponding pathologic conditions in this region with original illustrations and multimodality imaging examples. Highlighted in this article are the coracoclavicular joint, the classification and management of coracoid fractures, subcoracoid impingement, the coracoacromial arch and subacromial impingement, the coracohumeral ligament and the biceps pulley, the coracoclavicular ligament and its surgical reconstruction, adhesive capsulitis, the suprascapular notch and suprascapular notch impingement, subcoracoid bursitis, coracoid transfer procedures, and coracoid tumors. A brief summary of the pathophysiology, potential causes, and management options for each of the pathologic entities will also be discussed. ^©RSNA, 2016.

The diagnostic value of magnetic resonance imaging for different types of subscapularis lesions

PURPOSE

To investigate the accuracy of preoperative 1.5 T magnetic resonance imaging (MRI) interpreted with standardized procedure for diagnosing subscapularis (SSC) tears identified by arthroscopy. The diagnostic accuracy of MRI for different types of SSC lesions was also evaluated.

METHODS

Two-hundred and seventy-two consecutive patients with rotator cuff tears identified by arthroscopy were included into this study. All patients had preoperative MRI scans with 1.5 T strength. Totally, seven different signs of SSC tears were evaluated on MRI scans. The diagnostic value of MRI was evaluated, respectively, according to two classifications of SSC lesions. The definitive diagnosis for SSC lesions was based on the arthroscopic findings.

RESULTS

Among the 272 patients in this study, 107 (39 %) had SSC tears confirmed by arthroscopy. The surgeons correctly diagnosed 88 of 107 patients with SSC tears. The overall sensitivity was 82.2 %. The sensitivity of MRI for types I, II, III, IV and V was 70, 82.4, 96, 100 and 100 %, respectively, based on the classification by Lafosse. The sensitivity of MRI for partial-thickness and partial-width, full-thickness and partial-width, full-thickness and full-width tear was 75.3, 96.2, 100 %, respectively, according to the classification by Kim.

CONCLUSIONS

The sensitivity of MRI in predicting SSC tears preoperatively was improved with the current procedure. Understanding of certain MRI characteristics of SSC tears could increase the accuracy for diagnosing SSC lesions. 1.5 T MRI of the SSC was not reliable for predicting partial thickness and especially less than 1/3 width tears.

LEVEL OF EVIDENCE

III.