The anatomy of the coracohumeral ligament and its relation to the subscapularis muscle

Methods to analyse the long head of the biceps in the management of distal ruptures of the supraspinatus tendon. Part 1: the concept of the "biceps box": dynamic rotator interval approach. Incidence of lesions of the long head of the biceps tendon

INTRODUCTION

The area encompassing the long head of the biceps (LHB) can be represented as a rectangular parallelepiped. This geometric view can be likened to a box, the "biceps box", where the sides are the extrinsic structures and the LHB is the intrinsic structure. Since these structures are mobile in relation to each other, a dynamic "biceps box" model can modify assessments of the LHB, in its healthy or pathological state, and make the therapeutic approach to treating LHB lesions less arbitrary.

MATERIAL AND METHOD

In order to describe the different sides of the "biceps box", and to understand their possible physiological and pathological consequences, a literature review using PRISMA methodology was used.

RESULTS

The supraspinatus (SSP) has expansions on its anterior aspect that project anteriorly and cross the coracohumeral ligament (CHL). The most functionally important expansion is the fasciculus obliquus, which extends perpendicular to the axis of the tendon fibers of the SSP, divides the CHL into a deep and a superficial layer, and terminates on the superficial aspect of the subscapularis. The humeral insertion of the SSP may be binary, making a bridge over the LHB, with a posterior branch inserting on the greater tuberosity and an anterior branch on the lesser tuberosity. The superior glenohumeral ligament (SGHL) has a twisted course, downward and forward, and ends at the proximal opening of the bicipital groove with a flap on which the LHB rests. The bicipital pulley is not an independent structure but an arciform structure resulting from the fusion of several tissues.

DISCUSSION

The presence of structures linked together by common expansions in the 3 planes of space validates the relevance of a "biceps box" as a functional geometric model. The structure that acts as a crossroads through which all expansions pass is the CHL. An extrinsic SSP lesion can be compensated for by other "biceps box" structures, whereas an extrinsic SGHL lesion rarely exists without the presence of an intrinsic LHB lesion. The CHL constitutes a connective tissue crossed by a vasculonervous pedicle from the lateral pectoral nerve, which may explain some anterior shoulder pain attributed to the biceps.

CONCLUSION

The LHB can be likened to an intrinsic structure contained in a box whose sides are made up of different interconnected stabilizing structures defining the extrinsic structures. The concept of a dynamic "biceps box" allows LHB lesions to be accurately classified, separating extrinsic and intrinsic lesions, and thus potentially modifying therapeutic approaches to the LHB.

LEVEL OF EVIDENCE

IV; systematic review.

Adhesive Capsulitis of the Shoulder: Current Concepts on the Diagnostic Work-Up and Evidence-Based Protocol for Radiological Evaluation

Adhesive capsulitis is an idiopathic and disabling disorder characterized by intense shoulder pain and progressive limitation of active and passive glenohumeral joint range of motion. Although adhesive capsulitis has been traditionally considered a diagnosis of exclusion that can be established based on a suggestive medical history and the detection of supporting findings at the physical exam, imaging studies are commonly requested to confirm the diagnostic suspicion and to exclude other causes of shoulder pain. Indeed, clinical findings may be rather unspecific, and may overlap with diseases like calcific tendinitis, rotator cuff pathology, acromioclavicular or glenohumeral arthropathy, autoimmune disorders, and subacromial/subdeltoid bursitis. Magnetic resonance imaging, magnetic resonance arthrography, and high-resolution ultrasound have shown high sensitivity and accuracy in diagnosing adhesive capsulitis through the demonstration of specific pathological findings, including thickening of the joint capsule and of the coracohumeral ligament, fibrosis of the subcoracoid fat triangle, and extravasation of gadolinium outside the joint recesses. This narrative review provides an updated analysis of the current concepts on the role of imaging modalities in patients with adhesive capsulitis, with the final aim of proposing an evidence-based imaging protocol for the radiological evaluation of this condition.

The Effect of Arthroscopic Extra-Articular Entire Coracohumeral Ligament Release for Patients with Recalcitrant Frozen Shoulder

OBJECTIVE

The thickened coracohumeral ligament (CHL) is an important part of the typical manifestations and magnetic resonance imaging of frozen shoulder. However, only a few clinical studies with limited cases on arthroscopic extra-articular entire CHL release exist in the literature. This study was to evaluate the effect of arthroscopic extra-articular entire CHL release for patients with recalcitrant frozen shoulder.

METHODS

From February 2014 to February 2020, 81 cases of recalcitrant frozen shoulder patients treated with surgery in a single-center shoulder department and followed for more than 2 years were analyzed. Arthroscopic 360° capsular release was performed with intra-articular partial release (IPR group) or additional extra-articular entire release (IPR + EER group) of CHL. The same rehabilitation program was performed after surgery in both groups. Visual analogue scale (VAS) for pain, range of motion (ROM), and the Constant-Murley scoring system was evaluated before operation, at 3 months after operation, 6 months after operation, and the final follow-up. T-test, Mann-Whitney U-test and chi-squared test were used to compared data.

RESULTS

There were 39 patients in the IPR group, with an average follow-up of 29.2 months. A total of Forty-two patients in the IPR + EER group completed a mean follow-up of 25.7 months. All incisions healed in stages. There were significant differences in Constant-Murley shoulder score, VAS score, and ROM before operation and at the final follow-up in both groups (both P < 0.001). The VAS score of the IPR + EER group was lower than that of the IPR group at 3 months after surgery (P < 0.05), and 6 months after operation (P < 0.05). External rotation, internal rotation, and abduction of ROMs and Constant-Murley shoulder score were significantly greater in the IPR + EER group at 3 months (P < 0.001, P < 0.05, P < 0.001, P < 0.05, respectively) and 6 months after operation (P < 0.001, P < 0.05, P < 0.001, P < 0.05, respectively). At the last follow-up, there was no significant difference in forward flexion, internal rotation, and abduction of ROMs, VAS, and the Constant-Murley shoulder score between the IPR and IPR + EER groups. The external rotation of the IPR + EER group was still greater than that of the IPR group at the last follow-up (P < 0.001).

CONCLUSION

Arthroscopic extra-articular entire coracohumeral ligament release could solve early pain of shoulder joint, recover shoulder joint functions effectively, and achieve a satisfactory efficacy in the treatment of recalcitrant frozen shoulder.

Arthroscopic Subscapularis Repair With Preserved Biceps Anatomy

Arthroscopic subscapularis repair continues to improve with the advancement of surgical technique and critical focus on careful intraoperative evaluation. As identification of these tears increases, there is an expected increase in repair rates as well. Anatomically, the upper border of the subscapularis and the long head of the biceps (LHB) tendon are in close relation. Many surgeons have advocated concomitant LHB tenotomy versus tenodesis in conjunction with operative subscapularis tears. We hypothesized that in the setting of a preserved anatomic biceps pulley and no LHB pathology, isolated subscapularis repair would result in excellent clinical outcomes when compared with subscapularis repair and biceps tenotomy or tenodesis.

Adduction Manipulation of the Glenohumeral Joint versus Physiotherapy for Atraumatic Rotator Cuff Tears: A Randomized Controlled Trial

BACKGROUND

Atraumatic rotator cuff tears (ARCTs) are frequently concomitant with adduction restriction of the glenohumeral joint (GHJ). Adduction manipulation (AM) removes the restriction and relieves pain. The present study aimed to investigate the clinical efficacy of AM versus physiotherapy (PT) in ARCTs.

METHODS

Eighty-eight patients with adduction restriction were allocated to the AM and PT groups (n = 44 per group). The glenohumeral adduction angle (GAA) was calculated using X-rays at the first and last follow-up appointments. We recorded pain severity (visual analog scale, VAS), flexion, abduction, external rotation (ER), internal rotation (IR), and American Shoulder and Elbow Society (ASES) and Constant scores at baseline and at 1-, 3-, 6-, and 12- month follow-ups.

RESULTS

Forty-three patients (23 males, average age 71.3 years) in the AM group and 41 (16 males, average age 70.7 years) in the PT group were consequently analyzed. At the 1-month follow-up, VAS, shoulder motion except ER, ASES and Constant scores were much better in the AM group than in the PT group, whereas those in the PT group improved gradually up to 12 months. At the final follow-up, flexion, abduction, and Constant score were significantly better in the AM group than in the PT group. The GAA at the initial and final examinations was -21.6° and -3.2°, respectively, in the AM group, and -21.1° and -14.4°, respectively, in the PT group.

CONCLUSIONS

The AM procedure, which had better clinical efficacy than PT, is recommended as the first conservative treatment option for ARCTs.

Preemptive middle glenohumeral ligament release in arthroscopic rotator cuff repair does not reduce the postoperative stiffness: a retrospective comparative study

BACKGROUND

This study aimed to evaluate the efficacy of preemptive middle glenohumeral ligament (MGHL) release in arthroscopic rotator cuff repair (ARCR) to reduce postoperative stiffness.

METHODS

Patients who underwent ARCR were enrolled and allocated into two groups retrospectively: the preemptive MGHL release group (n = 44) and the preemptive MGHL non-release group (n = 42). Clinical outcomes were assessed and compared between the two groups, including the range of motion, Japanese Orthopedic Association Shoulder Score, Constant Shoulder Score, and the University of California, Los Angeles Score preoperatively and 3 months, 6 months, and 12 months postoperatively and complications. The integrity of the repaired tendon was assessed at the 12-month follow-up using magnetic resonance imaging.

RESULTS

There were no significant differences between the groups in all range of motion and all functional scores at any of the assessed time points. There was also no significant difference in the healing failure rate 2.3% in the preemptive MGHL group and 2.4% in the preemptive MGHL non-release group (p = .97), and postoperative stiffness was 2.3% in the preemptive MGHL group and 7.1% in the preemptive MGHL non-release group (p = .28). There was no postoperative instability in both group.

CONCLUSION

ARCR effectively facilitates the recovery of range of motion and function in patients with a rotator cuff tear. However, preemptive MGHL release could not be an effective method to reduce postoperative stiffness.

Dynamic Analysis of the Coracohumeral Ligament Using Ultra-Sonography in Shoulder Contracture

The coracohumeral ligament (CHL) is related to the range of motion of the shoulder joint. The evaluation of the CHL using ultrasonography (US) has been reported on the elastic modulus and thickness of the CHL, but no dynamic evaluation method has been established. We aimed to quantify the movement of the CHL by applying Particle Image Velocimetry (PIV), a technique used in the field of fluid engineering, to cases of shoulder contracture using the US. The subjects were eight patients, with 16 shoulders. The coracoid process was identified from the body surface, and a long-axis US image of the CHL parallel to the subscapularis tendon was drawn. The shoulder joint was moved from 0 degrees of internal/external rotation to 60 degrees of internal rotation at a rhythm of one reciprocation every 2 s. The velocity of the CHL movement was quantified by the PIV method. The mean magnitude velocity of CHL was significantly faster on the healthy side. The maximum magnitude velocity was significantly faster on the healthy side. The results suggest that the PIV method is helpful as a dynamic evaluation method, and in patients with shoulder contracture, the CHL velocity was significantly decreased.

Adhesive Capsulitis

Adhesive capsulitis, colloquially known as "frozen shoulder," is a relatively common disorder, affecting approximately 2% to 5% of the general population. The incidence may be higher as the condition can be relatively mild and self-limited and thus many patients who experience it may never present for treatment. It involves a pathologic process of gradual fibrosis of the glenohumeral joint that leads to limited active and passive range of motion, contracture of the joint capsule, and shoulder pain.

Alteration in coracohumeral ligament and distance in people with symptoms of subcoracoid impingement

BACKGROUND

Differentiation between subacromial impingement versus subcoracoid impingement are important for the treatment target. We evaluated the correlations between coracohumeral ligament (CHL) thickness and distance (CHD) and characterized the CHL and subscapularis (SSC) in subcoracoid impingement subjects.

METHODS

An observational, cross-sectional study was carried out. Twenty subcoracoid impingement subjects and age/gender matched controls were assessed in 4 different shoulder positions by ultrasonography.

RESULTS

Moderate correlations between CHL thickness with CHD (r = 0.455 in neutral rotation, p = 0.044; r = 0.483 in interior rotation, p = 0.031) were found in subacromial subjects. Subcoracoid impingement subjects had greater CHL thickness (difference = 0.3 mm, effect size = 0.85, p = 0.006), SSC tendon thickness (difference = 0.7 mm, effect size = 0.92, p = 0.01) and SSC/CHD occupation ratio (difference = 8%, effect size = 0.95, p = 0.005) compared with the control.

CONCLUSIONS

Coracohumeral distance is related to ligament thickness, especially in subacromial impingement subjects. Increased coracohumeral ligament and subscapularis thickness as well as decreased subscapularis/coracohumeral distance occupation ratio are characterized in subcoracoid impingement subjects. These quantitative measurements can be useful in identifying patients at risk of subcoracoid impingement from subacromial impingement.

Ultrasound Features for the Diagnosis of Adhesive Capsulitis/Frozen Shoulder: A Systematic Review

While ultrasound has become a preferred tool for musculoskeletal imaging, differing ultrasound findings that have been reported in patients with adhesive capsulitis can create confusion and misconceptions. This systematic review was aimed at summarizing all the ultrasound features currently described in the literature and providing a critical analysis of the sources to allow the readers to make a well-informed decision on the reliability of these features in the diagnosis of this condition. Databases were searched for original studies up to August 2021. Twenty-three studies were included. The QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies 2) tool was used to assess the quality of each selected article. Fourteen ultrasound features were identified. A quality analysis of all ultrasound features was performed using the GRADE (Grading of Recommendations, Assessment, Development and Evaluations) framework. All studies exhibited considerable heterogeneity in investigated ultrasound features and methodologies employed; therefore, meta-analysis was not considered to be appropriate. Hence, narrative synthesis was performed. The overall quality of each ultrasound outcome was found to be of "low" to "very low" level, and the generalisability of the results was also thought to be limited. Cautious interpretation and clinical correlation are recommended while applying these ultrasound features in clinical practice.

Effectiveness of ultrasound-guided fascia hydrorelease on the coracohumeral ligament in patients with global limitation of the shoulder range of motion: a pilot study

We conducted a prospective single-arm interventional study of the treatment efficacy of ultrasound-guided fascia hydrorelease (US-FHR) on the coracohumeral ligament (CHL) of patients with global limitation of shoulder range of motion (ROM) without local inflammation. The primary outcome was the change in passive ROM (pROM) of external rotation (ER) after first US-FHR. Secondary outcomes included the change in pROM of other directions from baseline, the pain visual analogue scale (pVAS) at the timepoints after each procedure (first, second US-FHR and rehabilitation) as well as the change in the Shoulder Pain and Disability Index (SPADI) from the first to the second visit. Eleven patients underwent US-FHR. The pROM of ER after the 1st US-FHR changed by a median of 7.1° (p < 0.01). There was a statistically significant improvement in the pROM of flexion, extension, abduction, external rotation, and internal rotation from baseline to each timepoints. The pVAS at rest showed no significant improvement, although the pVAS at maximal ER showed a trend towards improvement. The SPADI score decreased by a median of 13.4 (p < 0.01). No adverse events were observed. US-FHR on the CHL with or without rehabilitation might be an effective, less invasive treatment for patients with global limitation of shoulder ROM.

The Rotator Cable Does Not Stress Shield the Crescent Area During Shoulder Abduction

BACKGROUND

It is accepted by the orthopaedic community that the rotator cable (RCa) acts as a suspension bridge that stress shields the crescent area (CA). The goal of this study was to determine if the RCa does stress shield the CA during shoulder abduction.

METHODS

The principal strain magnitude and direction in the RCa and CA and shoulder abduction force were measured in 20 cadaveric specimens. Ten specimens underwent a release of the anterior cable insertion followed by a posterior release. In the other 10, a release of the posterior cable insertion was followed by an anterior release. Testing was performed for the native, single-release, and full-release conditions. The thicknesses of the RCa and CA were measured.

RESULTS

Neither the principal strain magnitude nor the strain direction in either the RCa or the CA changed with single or full RCa release (p ≥ 0.493). There were no changes in abduction force after single or full RCa release (p ≥ 0.180). The RCa and CA thicknesses did not differ from one another at any location (p ≥ 0.195).

CONCLUSIONS

The RCa does not act as a suspension bridge and does not stress shield the CA. The CA primarily transfers shoulder abduction force to the greater tuberosity.

CLINICAL RELEVANCE

The CA is important in force transmission during shoulder abduction, and efforts should be made to restore its continuity with a repair or reconstruction.

Association of damage to the coracohumeral ligament with anterosuperior rotator cuff degeneration revealed by anatomical dissection

The coracohumeral ligament (CHL) is an important structure of the biceps pulley which also merges with the rotator cuff. Which role it actually plays in the pathogenesis of rotator cuff degeneration (RCD) and rotator cuff tears (RCT) is still a point of discussion. The hypothesis of this study was, that macroscopic injury to the anterosuperior part of the rotator cuff also includes parts of or the whole CHL. Forty fresh-frozen shoulders were dissected and examined, the morphology of the rotator cuff and the coracohumeral ligament were evaluated and existing lesions documented. 27.5% of the shoulder joints showed an anterosuperior full-thickness RCT. 57.5% of all examined shoulder girdles showed at least a partial rupture of the CHL. A highly significant correlation (p < 0.001, rho = 0.529) between the presence of rotator cuff tears and ruptures of the CHL was found. Cartilage damage within the anterosuperior section of the humeral head was observed in 20% cases. In rotator cuff degeneration and atraumatic rotator cuff tears of the elderly population, the pathomechanism of full-thickness RCT is based on repetitive anterosuperior glenoid impingement. This is especially supported by the identification of a higher frequency of CHL lesions compared to RCT reported in this study. No intact CHL was identified in shoulders with damaged rotator cuff tendons.

Comma sign of subscapularis tear: diagnostic performance and magnetic resonance imaging appearance

BACKGROUND

The main aim of this study was to evaluate the performance of magnetic resonance imaging (MRI) and interobserver agreement in the identification of the comma sign. The second objective was to look for a correlation between the comma sign and the detachment of the superficial fascia of the subscapularis.

MATERIALS AND METHODS

Two radiologists, blinded to the arthroscopic findings, retrospectively assessed the magnetic resonance images of 110 shoulders and were asked to assess the presence of the comma sign and the intact subscapularis fascia. The inter-reader agreement and the MRI performance values for detection of the comma sign were calculated. In addition, the association between the intact superficial subscapularis fascia and the comma sign was evaluated.

RESULTS

The agreement between the 2 radiologists was perfect. The following values were obtained: sensitivity, 90.9%; specificity, 98.8%; positive predictive value, 95.2%; negative predictive value, 97.7%; and accuracy, 97.2%. No association between the comma sign and subscapularis fascia lesions was found.

CONCLUSION

MRI appears to be a reliable method for preoperative assessment of the comma sign. The comma sign appears not to be formed by the detached subscapularis fascia.

Anterior Cable Tears in Arthroscopic Rotator Cuff Repairs

Purpose

To determine whether anterior cable tears could be identified at the time of arthroscopic rotator cuff repair and determine the characteristics of the anterior cable tears identified.

Methods

From 2016 to 2017 all shoulder arthroscopies had data collected prospectively at the time of surgery, specifically including injury to the capsular and tendon zones of insertion on the greater tuberosity. Anterior cable position and degree of injury and medialization were recorded, as well as complete findings of the diagnostic arthroscopy. The inclusion criterion was primary shoulder arthroscopy. The exclusion criterion was any revision shoulder arthroscopy. All arthroscopic rotator cuff repairs (ARCR) were grouped together and all other nonarthroscopic rotator cuff repair surgeries (non-ARCR) were grouped together.

Results

In total, 118 shoulder arthroscopies had data collected prospectively at the time of surgery: 90 primary shoulder arthroscopies met the inclusion criteria; 28 were excluded because they were revision surgeries. There were 42 patients in the ARCR group (Group 1). Six of these were partial tears, and 36 were full-thickness tears. There were 48 patients in the non-ARCR group (Group 2). The non-ARCR Group 2 served as an anatomic baseline for ARCR Group 1. In all 90 shoulders, the rotator cable and anterior cable were identified. Group 1 (ARCR) incidence of anterior cable tears with abnormal position was 71.4% compared to 2.1% in group 2 (non-ARCR) (P < .001) Group 1 (ARCR) incidence of anterior cable tears with normal anterior cable position (n = 12) was compared to abnormal anterior cable position (n = 30). Injury to the anterior footprint capsular and tendon zones were compared. Normal anterior cable position correlated with no or low-grade injury to anterior footprint capsular zone. (Nimura zone C1). Abnormal anterior cable displacement graded as moderate (n = 20) and severe (n = 10) were compared for injury to the anterior footprint. Moderate displacement correlated with complete or high grade injury to C1 in 85% and complete injury to R1 in 45% (P < .001 and .049). In severe displacement complete C1 injury was 100%, and complete R1 injury was 100% (P < .001 and .001).

Conclusions

Anterior cable tears are universally identified in ARCR. Three patterns of medial displacement severity correlated with injury to a crucial insertion zone (C1) at the anterior footprint. The degree of anterior cable disruption at the anterior footprint and displacement was commonly disproportionately greater than the injury to the supraspinatus.

Level of Evidence

Level III, diagnostic study.

Correlations Between Range of Motion and Elasticity of the Coracohumeral Ligament Evaluated With Shear-Wave Elastography

Context: Range of motion (ROM) in the glenohumeral joint decreases with age in healthy subjects; however, the underlying mechanism remains unclear. The process of aging of the joint capsule, including the coracohumeral ligament (CHL), could affect ROM limitation. Objective: This study investigated correlations between elasticity of the CHL, evaluated by means of shear-wave elastography, and age, side dominance, and ROM in healthy individuals. Design: Experimental study. Setting: Laboratory. Subjects: Eighty-four healthy volunteers (39 men and 45 women, mean age: 42.6 y) were included. Main Outcome Measures: Subjects were divided into 3 age groups: younger (20–39 y), middle (40–59 y), and older (≥60 y) age groups. With participants in the supine position, CHL elasticity in both shoulders was evaluated in both neutral and 30° external rotation, with arms at the sides. ROM, including forward flexion, lateral elevation, external rotation, 90° abduction with external rotation, and hand behind the back were measured with participants in the standing position. Results: The CHL elastic modulus was higher in the older group than in the younger group in the neutral (78.4 kPa [SD: 37.1] and 56.6 kPa [SD: 31.7], respectively) and 30° external rotation positions (135.5 kPa [SD: 63.5] and 71.4 kPa [SD: 32.2], respectively). Negative correlations were found between the CHL elastic modulus and ROM in terms of 30° external rotation and both external rotation (R = −.59, P = .02) and 90° abduction with external rotation (R = −.71, P = .003) in the older group, with correlation coefficients increasing with age. Conclusions: Significant correlations were identified between CHL elasticity and ROM in both external rotation and 90° abduction with external rotation with increasing age. Decreased CHL elasticity was strongly associated with decreased shoulder ROM in middle-aged and older individuals.

RAGE-dependent NF-kB inflammation processes in the capsule of frozen shoulders

BACKGROUND

The etiology of frozen shoulder (FS) remains uncertain. Advanced glycation end-products (AGEs) cause the cross-linking and stabilization of collagen and are increased in FS. The purpose of this study was to elucidate the pathogenesis of FS by evaluating the receptor of AGE (RAGE)-dependent pathways.

METHODS

Tissue samples of the coracohumeral ligament (CHL) and anterior inferior glenohumeral ligament (IGHL) were collected from 33 patients with FS, with severe stiffness, and 25 with rotator cuff tears (RCTs) as controls. Gene expression levels of RAGE, high-mobility group box 1 (HMGB1), Toll-like receptor 2 (TLR2), TLR4, nuclear factor-kappa B (NF-kB), and cytokines were evaluated using a quantitative real-time polymerase chain reaction. The immunoreactivities of carboxymethyllysine (CML), pentosidine, and RAGE were also evaluated. CML and pentosidine were further evaluated using high-performance liquid chromatography.

RESULTS

Gene expression levels of RAGE, HMGB1, TLR2, TLR4, and NF-kB were significantly greater in the CHLs and IGHLs from the FS group than in those from the RCT group. Immunoreactivities of RAGE and CML were stronger in the CHLs and IGHLs from the FS group than in those from the RCT group. Pentosidine was weakly immunostained in the CHLs and IGHLs from the FS group. CML using high-performance liquid chromatography was significantly greater in the CHLs and IGHLs from the FS group than in those from the RCT group.

CONCLUSIONS

AGEs and HMGB1 might play important roles in the pathogenesis of FS by binding to RAGE and activating NF-kB signaling pathways. Suppression of these pathways could be a treatment option for FS.

Diagnostic accuracy of ultrasound in subscapularis tendon abnormalities and the importance of operator experience

OBJECTIVE

This study aimed to investigate the reasons behind the compliance, diagnostic success, and failure of ultrasound (US) examinations of two radiologists with reference to magnetic resonance imaging (MRI) in the abnormalities of subscapularis (SSC) tendon, including tendinosis.

METHODS

One less experienced radiologist (operator-1) and one senior radiologist, experienced in the musculoskeletal US (operator-2), performed the shoulder US on 78 patients (mean age: 53.18 ± 10.89 [22-73] years), who had undergone MRI for routine reasons except malignancy, within 1-4 weeks of MRI. Tendinopathy, partial (PT), or full-thickness (FT) tears were recorded in the subscapularis. The thickness of the anterior and lateral soft tissues in the shoulder girdle was measured by MRI. The inter-operator agreement on the US results, the US-MRI compliance for each operator, and the relationship between the US-MRI compliance and tissue thickness were investigated.

RESULTS

The inter-operator agreement on the US findings was moderate. The US-MRI compliance was fair for operator-1, but substantial for operator-2. The circumferential soft tissue thickness and US-MRI compliance were not correlated (p>0.05). The interobserver agreement in US was moderate (K: 0.415). The US-MRI compliance was fair for operator-1 (K: 0.344) and substantial for operator-2 (K: 0.616). The accuracy rates for the differentiation of normal tendon, tendinosis, PT, and FT were 59%, 75%, 72%, and 100%, respectively, for operator-1 and 87%, 83%, 85%, and 100%, respectively, for operator-2. However, the respective sensitivity of operator-1 was 46%, 19%, 44%, and 100%; and operator-2 was 91%, 67%, 82%, and 100%. The diagnostic performance of operator-1 was lower, except for FT.

CONCLUSION

The thickness of the surrounding tissue does not affect the US results. The differentiation between tendinosis and PT tear is difficult (more prominent in less experienced user); however, because this would not change the treatment choice, shoulder US is recommended after basic training in subscapularis pathologies.

LEVEL OF EVIDENCE

Level II, Diagnostic.

Quantitative and Qualitative Analyses of the Glenohumeral Ligaments: An Anatomic Study

BACKGROUND

While several studies have qualitatively described the anatomy of the glenohumeral ligaments, there remains a lack of consensus regarding their quantitative humeral and glenoid attachment sites.

PURPOSE

To quantitatively and qualitatively describe the anatomic humeral and glenoid attachment sites of the glenohumeral ligaments and their relationship to well-established anatomic landmarks.

STUDY DESIGN

Descriptive laboratory study.

METHODS

A total of 10 nonpaired, fresh-frozen human cadaveric shoulders were included in this study. A 3-dimensional coordinate measuring device was used to quantify the location of pertinent bony landmarks and soft tissue attachment areas. All subcutaneous tissues and musculature were removed, with the exception of the rotator cuff (respective muscle bellies cut at their musculotendinous junctions) and the long head of the biceps tendon. The superior glenohumeral ligament (SGHL), middle glenohumeral ligament (MGHL), anteroinferior glenohumeral ligament (AIGHL), posteroinferior glenohumeral ligament (PIGHL), and coracohumeral ligament (CHL) were then transected. Coordinates of points along the perimeters of attachment sites were used to calculate areas, while coordinates of center points were used to determine distances between surgically relevant attachment sites and pertinent bony landmarks.

RESULTS

The mean length of the SGHL humeral attachment along the intra-articular cartilage margin was 9.5 ± 3.2 mm, spanning from 12:55 to 1:40, while the SGHL glenoid attachment to the labrum was 1.9 ± 1.2 mm medial to the most lateral extent of the labral rim, spanning from 12:30 to 12:45. The mean length of the MGHL attachment along the intra-articular cartilage margin was 16.4 ± 3.0 mm, equating to 2:10 to 3:35 on the humeral head clockface, and the glenoid attachment was confluent with the labrum, attaching 1.5 ± 1.0 mm medial to the most lateral extent of the labral rim and thus extending from 1:50 to 2:35 on the glenoid clockface. The mean length of the AIGHL attachment along the intra-articular cartilage margin was 12.0 ± 3.0 mm, spanning from 4:05 to 5:10 on the humeral head clockface. The AIGHL bony footprint on the glenoid neck was 48.4 ± 24.5 mm². The confluent attachment of the AIGHL to the labrum was 1.2 ± 0.9 mm medial to the most lateral extent of the labral rim, corresponding to 3:30 to 4:05 on the glenoid clockface. The mean length of the PIGHL attachment along the intra-articular cartilage margin was 12.0 ± 1.4 mm, spanning from 7:40 to 8:50 on the humeral head clockface. The PIGHL attachment to the labrum was 1.2 ± 0.5 mm medial to the most lateral extent of the labral rim. This attachment to the labrum was calculated to span from 7:35 to 8:50 on the glenoid clockface. The mean length of the CHL origin from the coracoid was 12.9 mm, with its most anterior point located a mean of 14.1 mm from the tip of the coracoid. The mean length of the CHL attachment along the intra-articular cartilage margin was 10.0 ± 4.0 mm, spanning from 11:55 to 12:40 on the humeral head clockface.

CONCLUSION

Glenohumeral ligaments were consistently identified in all specimens with minor anatomic variability for the SGHL, MGHL, AIGHL, and PIGHL. Important landmarks including the cartilage surface of the humerus, the bicipital groove, and the clockface can be utilized intraoperatively when attempting anatomic repair of these structures.

CLINICAL RELEVANCE

There are multiple open and arthroscopic shoulder procedures that rely on anatomic restoration of these static stabilizers to provide optimal shoulder function and prevent recurrent instability. The qualitative descriptions are comparable with current literature; however, this study is the first to quantify the glenohumeral capsular and ligamentous attachments. The data provided allow for reliable landmarks to be established from known bony and soft tissue structures.

A new pathophysiology of atraumatic rotator cuff tears: adduction restriction of the glenohumeral joint

Background

The pathophysiology of atraumatic rotator cuff tears (ATTs) has not been fully understood. Adduction restriction of the glenohumeral joint can cause pain and disability in patients with ATTs. We aimed to use our adduction test (pushing the humerus toward the side in the coronal plane with scapular fixation) to fluoroscopically measure the glenohumeral adduction angle (GAA) and to assess the effectiveness of adduction manipulation.

Materials and methods

Fifty-five patients with ATTs were included in the study. The GAAs of the patients vs. healthy subjects without ATTs were measured fluoroscopically and compared. During the test, patients showed restriction and expressed pain. The visual analog scale (VAS) score, passive range of motion (ROM), and the American Shoulder and Elbow Surgeons score at the initial visit were compared with those after adduction manipulation.

Results

Of the patients, 41 (75%) had positive adduction test results. A higher percentage of positive adduction test results was observed in smaller tears. The average GAA was –21.4° on the affected side, which was smaller than that on the unaffected side, at –2.8° (P < .001), and that in healthy subjects, at 4.8° (P < .001). After manipulation, the GAA was –0.8° (P < .001) and the VAS score, the American Shoulder and Elbow Surgeons score, and all ROM values significantly improved up to the level on the unaffected side.

Conclusion

Adduction restriction of the glenohumeral joint was identified in 75% of all the patients with ATTs. Adduction manipulation significantly reduces the VAS score and restores the ROM. Adduction restriction is considered a crucial pathophysiology of ATTs.

Optimal Cut-Off Value of the Coracohumeral Ligament Area as a Morphological Parameter to Confirm Frozen Shoulder

BACKGROUND

Thickened coracohumeral ligament (CHL) is one of the important morphological changes of frozen shoulder (FS). Previous research reported that coracohumeral ligament thickness (CHLT) is correlated with anterior glenohumeral instability, rotator interval and eventually FS. However, thickness may change depending on the cutting angle, and measurement point. To reduce measurement mistakes, we devised a new imaging criteria, called the coracohumeral ligament area (CHLA).

METHODS

CHL data were collected and analyzed from 52 patients with FS, and from 51 control subjects (no evidence of FS). Shoulder magnetic resonance imaging was performed in all subjects. We investigated the CHLT and CHLA at the maximal thickened view of the CHL using our picture archiving and communications system. The CHLA was measured as the whole area of the CHL including the most hypertrophied part of the MR images on the oblique sagittal plane. The CHLT was measured at the thickest point of the CHL.

RESULTS

The average CHLA was 40.88 ± 12.53 mm² in the control group and 67.47 ± 19.88 mm² in the FS group. The mean CHLT was 2.84 ± 0.67 mm in the control group and 4.01 ± 1.11 mm in the FS group. FS patients had significantly higher CHLA (P < 0.01) and CHLT (P < 0.01) than the control group. The receiver operator characteristic analysis showed that the most suitable cut-off score of the CHLA was 50.01 mm², with 76.9% sensitivity, 76.5% specificity, and area under the curve (AUC) of 0.87. The most suitable cut-off value of the CHLT was 3.30 mm, with 71.2% sensitivity, 70.6% specificity, and AUC of 0.81.

CONCLUSION

The significantly positive correlation between the CHLA, CHLT and FS was found. We also demonstrate that the CHLA has statistically equivalent power to CHLT. Thus, for diagnosis of FS, the treating physician can refer to CHLA as well as CHLT.

Increased Stiffness of Rotator Cuff Tendons in Frozen Shoulder on Shear Wave Elastography

OBJECTIVES

To evaluate the stiffness and morphologic characteristics of the capsule, rotator cuff tendons and muscles, coracohumeral ligament (CHL), and long head of the biceps in patients with frozen shoulder using shear wave elastography (SWE) with B-mode ultrasound.

METHODS

Thirty-two patients with frozen shoulder were divided into freezing and frozen phases. All patients had limitations of their range of motion without rotator cuff tears. Stiffness was measured by SWE in the supraspinatus (SSp) tendon, infraspinatus (ISp) tendon, SSp muscle, ISp muscle, teres minor muscle, upper and lower trapezius muscles, posterior capsule, CHL, and long head of the biceps. The posterior capsule and CHL thicknesses were also investigated with B-mode ultrasound. All values were compared in the affected and unaffected shoulders in each phase.

RESULTS

The SWE values for the SSp and ISp tendons in the freezing phase and the CHL in the frozen phase were significantly greater on the affected side than the unaffected side (mean ± SD, 280.4 ± 125.3 versus 178.1 ± 73.3, 318.4 ± 110.7 versus 240.8 ± 91.5, and 287.2 ± 135.3 versus 214.1 ± 91.1 kPa, respectively; P < .05). The posterior capsule in both the freezing and frozen phases and the CHL in the frozen phase were significantly thicker on the affected side than the unaffected side (1.3 ± 0.2 versus 0.9 ± 0.3, 1.2 ± 0.4 versus 0.9 ± 0.3, and 4.4 ± 1.4 versus 3.3 ± 1.1 mm; P < .01).

CONCLUSIONS

The SWE values of the both SSp and ISp tendons increased in the freezing phase, and that of the CHL also increased in the frozen phase. Not only the change in thickness of the capsule but also the change in stiffness of the rotator cuff may correlate with frozen shoulder.

The effect of concomitant coracohumeral ligament release in arthroscopic rotator cuff repair to prevent postoperative stiffness: a retrospective comparative study

PURPOSE

This study was to evaluate the efficacy and safety of coracohumeral ligament (CHL) release from the coracoid process concomitant with arthroscopic rotator cuff repair for preventing postoperative stiffness.

METHODS

Data on patients who underwent arthroscopic rotator cuff repair with a minimum follow-up of 1 year were collected retrospectively. Propensity score matching (1-to-1) was performed between a no-releasing group (Group I) and CHL-releasing group (Group II). In total, 76 patients in each group were matched. Clinical outcomes were assessed and compared between the two groups, including range of motion (ROM) and visual analogue scale for pain (pVAS) at postoperative 3 months, 6 months, and 1 year. The integrity of the repaired tendon was assessed at 1-year follow-up using either magnetic resonance imaging or ultrasonography.

RESULTS

External rotation (ER) at side at postoperative 3 months in Group II was better than that in Group I (48.6° ± 11.6° vs. 38.4° ± 13.0°, P < 0.001). When evaluating only patients with a small-to-medium sized tear at postoperative 3 months, ER at side was 49.8° ± 10.9° in Group II versus 37.8° ± 13.1° in Group I (P < 0.001). In patients with a large-to-massive sized tear, however, there was no significant difference in ER at side at postoperative 3 months (n.s.). There was no significant difference in ROM and functional scores at postoperative 6 months and 1 year, and there was no significant difference in healing failure rate (6 cases in Group I (7.9%), 2 cases in Group II (2.6%); n.s.). No complications of the CHL release procedure occurred.

CONCLUSIONS

In arthroscopic rotator cuff repair, CHL release from the coracoid process without creating a rotator interval defect could be an effective and safe method to prevent early postoperative stiffness, especially ER at side in patients with a small-to-medium sized tear. Therefore, CHL release can be used as a selective procedure to prevent postoperative stiffness in patients that may benefit from this procedure with decreased preoperative ER compared to the normal side.

LEVEL OF EVIDENCE

Level III.

Coracohumeral Ligament Reconstruction for Patients With Multidirectional Shoulder Instability

Coracohumeral ligament pathology arises from acute trauma, capsular thickening, or congenital connective tissue disorders within the glenohumeral joint. Recent studies have highlighted the significance of this pathology in multidirectional shoulder instability because insufficiency of the rotator interval has become increasingly recognized and attributed to failed shoulder stabilization procedures. The diagnosis and subsequent treatment of coracohumeral ligament pathology can be challenging, however, because patients usually present with a history of failed surgical stabilization and persistent laxity. At the time of presentation, most patients have undergone failed nonoperative treatments and are indicated for surgical intervention. One of the options for the treatment of coracohumeral ligament pathology is reconstruction. The purpose of this Technical Note is to describe our preferred surgical technique for the reconstruction of the coracohumeral ligament. Research was performed at the Steadman Philippon Research Institute.

Histologic characteristics of the subscapularis tendon from muscle to bone: reference to subscapularis lesions

BACKGROUND

Although subscapularis tendon lesions seem to differ from those of the supraspinatus tendon, the features they have in common suggest that the subscapularis tendon may also have 2 distinct layers. Our aim was therefore to characterize the histologic structure of the subscapularis tendon from its humeral insertion point to the musculotendinous junction.

MATERIAL AND METHODS

A histologic study was performed on 10 autopsy samples. The subscapularis tendon was extracted in one piece from the musculotendinous junction to the humeral insertion point and was prepared using standard (hematoxylin-eosin-saffron) staining.

RESULTS

Histologic analysis revealed 2 fibrous layers, distinguishable by the orientation of the collagen bundles. The deep layer was thinner and composed of parallel longitudinal collagen fibers inserting onto the lesser tuberosity flush with the cartilage. The superficial layer was thicker and composed of interdigitated collagen bundles inserting onto the lesser and the greater tuberosity after splitting into 2 bands, 1 lining the floor of the bicipital groove, and the other extending over the long head of the biceps tendon across the groove. Each layer formed an independent musculotendinous junction in the subscapularis muscle.

CONCLUSIONS

The subscapularis tendon is composed of 2 distinct fibrous layers, just like the supraspinatus tendon, but arranged differently. The superficial layer of the subscapularis tendon passes across the bicipital groove and forms a fibrous ring around the long head of the biceps tendon that stabilizes the latter in the bicipital groove. These results explain some of the specific features of subscapularis tears described in the literature, namely, delamination and biceps subluxation.

Accuracy of Two Ultrasound-Guided Coracohumeral Ligament Injection Approaches: A Cadaveric Study

BACKGROUND

Glenohumeral idiopathic adhesive capsulitis is a common shoulder condition that hinders functionality. Addressing the pathology has been extensively researched. Ultrasound (US)-guided injections have shown their efficacy. However, no study has been conducted to compare anatomical accuracy between different approaches in targeting the coracohumeral ligament (CHL).

OBJECTIVE

To investigate whether US-guided injection of the CHL can be performed accurately using either the rotator interval (RI) or the coracoidal (CO) approach.

METHODS

An experimental cadaveric case series.

SETTING

Anatomy laboratory.

SPECIMENS

Both shoulders of 13 Thiel-embalmed cadavers.

INTERVENTIONS

Three physiatrists each injected a 0.1 mL bolus of colored dye in both shoulders of each cadaver using either the RI or the CO approach under US guidance. Each cadaver received a total of six injections (three injections per shoulder). The accuracy of the injection was determined following shoulder dissection by an anatomist.

MAIN OUTCOME MEASURE

The accuracy of the US-guided injection of the CHL.

RESULTS

The RI approach yielded 36 accurate injections, giving it an accuracy of 100%. With the CO approach two injections were deemed inaccurate yielding an accuracy of 94%. There was no significant difference in accuracy between all operators.

CONCLUSIONS

US-guided injection of the CHL can be performed accurately with both the RI and CO approaches. The RI approach was likely to be more accurate.

Blood flow evaluation by dynamic magnetic resonance imaging of symptomatic rotator cuff tears and frozen shoulders

BACKGROUND

This study compared imaging findings of blood flow changes between symptomatic rotator cuff tear (RCT) and frozen shoulder (FS) by using 3-dimensional dynamic magnetic resonance imaging (MRI) to determine the clinical characteristics of symptomatic RCT.

METHODS

The 2 study groups comprised 31 symptomatic RCT patients who underwent arthroscopic rotator cuff repair and 30 patients with FS. We denoted abnormal blood flow detected around the glenohumeral joint as the burning sign (BS). We evaluated the characteristics of dynamic MRI and compared them between BS-positive and BS-negative patients in the RCT group.

RESULTS

All members of the FS group showed the BS. Conversely, the incidence of the BS in RCT patients was 53% (16 of 31). The BS in RCT and FS patients was observed in the rotator interval in 16 shoulders, in the axillary pouch in 3 shoulders (P < .01), and in the intertubercular groove in 10 RCT and 12 FS patients. In the RCT group, 16 patients with BS had a statistically significantly higher Numeric Rating Score at rest (P = .0005) and in motion (P = .04) than the 15 patients without BS and exhibited a higher rate of small and medium tears and a higher rate of shoulder contracture.

CONCLUSION

Dynamic MRI of symptomatic RCT (53.3%) highlighted abnormal vascularization around the glenohumeral joint, which may be associated with pain and contracture in RCT as in FS.

Correlations between Capsular Changes and ROM Restriction in Frozen Shoulder Evaluated by Plain MRI and MR Arthrography

Background:

Evaluation of the Range Of Motion (ROM) is one of the important procedures for shoulder disorders. The purpose of this study was to investigate correlations between capsular changes and ROM restrictions evaluated by both plain magnetic resonance imaging (MRI) and Magnetic Resonance Arthrography (MRA) in the same patients with frozen shoulder.

Methods:

Between March 2015 and June 2016, 24 patients with frozen shoulders (13 male and 11 female patients, mean age 60.5) with severe ROM restriction who underwent both MRI and MRA on the same affected side were evaluated. We evaluated 1) ROM, 2) the coracohumeral ligament (CHL) thickness, 3) the joint capsule thickness in the axillary recess (humeral and glenoid sides), 4) the area of the axillary recess, and 5) the capsular area of the axillary recess.

Results:

Positive correlations were found between the axillary area and forward flexion (FF) (R = 0.43, P = 0.035), lateral elevation (LE) (R = 0.66, P<0.001), external rotation (ER)(R = 0.43, P = 0.035), 90° abduction with external rotation (AER)(R = 0.56, P = 0.004), and hand behind the back (HBB)(R = 0.6, P = 0.002) on MRA. Negative correlations were found between the joint capsule at the glenoid side and ER and HBB in both MRI and MRA.

Conclusion:

The axillary area was significantly correlated with ROM restriction in FF, LE, ER, AER, and HBB on MRA. Thickness of the joint capsule at the glenoid side is an important factor for ROM restriction in frozen shoulder.

Level of Evidence:

Level 3, Study of Diagnostic Test.

Ultrasound-guided coracohumeral ligament release

Long-term follow-up of patients with adhesive capsulitis (AC) reveals that approximately half of them suffer from a limited range of shoulder motion, particularly external and/or internal rotation. We report the surgical technique and short-term clinical outcomes of ultrasound-guided release of the thickened coracohumeral (CH) ligament in 8 patients (9 shoulders) with AC. Passive external rotation with the arm by the side significantly increased from an average of 18° preoperatively to 47° immediately after CH ligament release. VAS and ASES scores were improved at 3months follow-up in all 9 shoulders, and maintained at 6months follow-up in 6 shoulders. No procedure-related adverse events developed over the 6-month follow-up period. Ultrasound-guided release for thickened CH ligament is a reliable and effective minimally invasive surgery for persistent limited external rotation due to AC of the shoulder.

Effects of Arthroscopic Coracohumeral Ligament Release on Range of Motion for Patients with Frozen Shoulder

Background:

A thickened coracohumeral ligament is a highly specific manifestation of, and primary restraint against external rotation in frozen shoulders.

Objective:

The purpose of this study was to evaluate the effects of complete arthroscopic coracohumeral ligament release on range of motion in frozen shoulder.

Methods:

Fifty-two consecutive shoulders in 52 patients were treated between April 2015 and June 2016. To evaluate solely glenohumeral range of motion, the scapula was fixed by an examiner with one hand (without palpating scapular motion), and range of motion was measured using a goniometer. For the first step, arthroscopic pancapsular release was performed in a beach-chair position with (Group 1) or without (Group 2) complete coracohumeral ligament release. For the final step, the remaining coracohumeral ligaments in Group 2 were released and the ranges of motion were compared to those in Group 1.

Results:

The average age of the patients was significantly higher in Group 1, but there were no significant differences between the two groups with respect to sex, affected side, preoperative range of motion, or American Shoulder and Elbow Society Score. Abduction, external rotation at adduction, and external and internal rotations at 90° of flexion in Group 1 were significantly greater than those in Group 2. After the additional release of the remaining coracohumeral ligaments in Group 2, all ranges of motion were significantly recovered and there was no significant difference between the groups.

Conclusion:

Complete coracohumeral ligament release is a recommended intraoperative procedure for regaining full range of motion in frozen shoulders.

Clinical outcome of arthroscopic capsular release for frozen shoulder: essential technical points in 255 patients

Background

The purpose of this study was to investigate the long-term clinical outcome and its related factors regarding the severity of adhesion of CH ligament over long head of biceps (LHB) after shoulder arthroscopic capsular release for frozen shoulder with technical points in 255 patients.

Methods

We performed arthroscopic capsular release for frozen shoulder in 267 shoulders of 255 patients, 112 males and 143 females, with mean age of 56.39 years, mean disease duration periods of 0.934 years for conservative treatment, and mean follow-up periods of 5.6 years. The frozen shoulders were divided based on the severity of adhesion between CH ligament over LHB: those with slight degree of synovitis, no adhesion by obtuse rod, and slight thickness of the released capsule (type A), those with moderate degree of synovitis, moderate adhesion of the LHB by obtuse rod, and moderate thickness of the released capsule (type B), and those with severe degree of synovitis, severe adhesion of the LHB by obtuse rod, and severe thickness of the released capsule adhesion and a flatly shaped LHB (type C). We assessed the clinical factors related to the scoring of the shoulders by the criteria of the American Shoulder and Elbow Surgeons (ASES) and the relationship with severity of LHB adhesion.

Results

The ASES scores improved at 5 years postoperatively in all three groups significantly. The range of motion also significantly improved in all three groups significantly. The severity of the LHB adhesion over the CH ligament was confirmed to influence the ASES scores before and after the arthroscopic capsular release. There was a significant difference between type A and type B (p < 0.0001) or type C (p < 0.0001) before and after surgery. Logistic regression analysis showed disease duration, diabetes mellitus (DM), and ASES score were significantly associated to the severity type of LHB, especially DM has high odds ratio and was a risk factor for LHB adhesion. There is no adverse event including dislocation or axillary nerve injury and recurrence after arthroscopic capsular release at 5 years after surgery.

Conclusions

The long-term results of arthroscopic capsular release in frozen shoulder were confirmed in 255 patients. The severity of LHB adhesion over the CH ligament, a pathological condition related to DM as a risk factor, seems to play an important role in the functional outcome. Therefore, the sufficient release of LHB was essential technical point for arthroscopic capsular release in frozen shoulder.

Location and thickness of delaminated rotator cuff tears: cross-sectional analysis with surgery record review

Background

To facilitate better treatment, we analyzed morphologic features of delamination from the viewpoint of the location of delamination and the thickness of each layer.

Materials and Methods

Of 270 shoulders that consecutively underwent arthroscopic rotator cuff repair, 210 were included. During the operation, the surgeon assessed the size of the rotator cuff tear, determined the presence and location of delamination, and compared the thickness between superficial and deep layers if delamination was present. Immediately after the operation, the surgeon wrote down the data in the record form. The authors retrospectively referred to these surgical records to investigate those items.

Results

Delamination was found in 111 of 210 shoulders. The overall preoperative Constant score did not significantly differ between the 2 groups. In terms of the location, 7.2% cases had delamination in the anterior part, 74.8% in the posterior part, and 18.0% in both parts (Fleiss κ = 0.9). The larger the rotator cuff tear, the more frequently the delamination was limited to the posterior part (trend P = .001). As for layer thickness comparison, 40.0% of the shoulders with small tears, 38.8% with medium tears, 66.0% with large tears, and 80.0% with massive tears had a thicker deep layer than superficial layer (Fleiss κ = 0.9). The larger the size of the rotator cuff tear, the more frequently the deep layer was thicker than the superficial layer (trend P = .001).

Conclusions

The larger the rotator cuff tear, the more carefully shoulder surgeons should observe and treat the posterior and deep part of delamination.

Arthroscopic Coracohumeral Ligament Release for Patients With Frozen Shoulder

Arthroscopic pancapsular release has been recommended for recalcitrant frozen shoulder, but regaining range of motion has not been sufficient compared with the unaffected side. There is no consensus about the reasons for these remaining restrictions in range of motion, but residual capsular or connective tissue must be considered a candidate. A thickened coracohumeral ligament at the rotator interval has been reported as one of the most specific manifestations of frozen shoulder. It covers wider portions of the subscapularis tendon, supraspinatus tendon, and infraspinatus tendon than previously reported. We describe an arthroscopic surgical technique for the release of the entire coracohumeral ligament including the subscapularis and supraspinatus portions and the release of the inferior and posterior parts of the glenohumeral ligament using the 7-o'clock portal. These procedures are essential and reliable methods to release the entire joint capsule to regain full range of motion for frozen shoulder.

Fracture line morphology of complex proximal humeral fractures

BACKGROUND

The aim of this study was to assess proximal humeral fracture patterns using 3-dimensional computed tomography images and relate them to the normal osseous landmarks and soft-tissue attachments.

METHODS

Forty-eight 3-dimensional computed tomography scans of proximal humeral fractures were retrospectively collected, and the fractures were transcribed onto proximal humeral templates. We analyzed the common location and orientation of the fracture lines, with a focus on fractures of the articular surface, tuberosities, metaphysis, and proximal diaphysis. These fractures were compared with the attachments of the rotator cuff and glenohumeral capsule.

RESULTS

Fifty-two percent of the fractures involved the articular surface. No fractures passed through the bicipital groove, and fractures were more commonly found on the posterior lesser tuberosity and on the anterior greater tuberosity, coinciding with the intervals between the rotator cuff tendon insertions. Intracapsular fractures of the calcar were more common (68%) than extracapsular fractures (32%). On the anterolateral aspect of the proximal humerus, fractures radiated from the articular margin, vertically down through the tuberosity zone between the rotator cuff footprints, meeting horizontally oriented fractures in the metaphyseal zone. On the posterior aspect, vertical fractures from the tuberosity zone continued downward to the metaphyseal zone adjacent to the infraspinatus and teres minor footprints.

CONCLUSIONS

Fractures of the proximal humerus follow characteristic patterns. Fractures frequently split the greater tuberosity and are closely related to the intervals of the rotator cuff attachments.

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.

The Rotator Interval - A Link Between Anatomy and Ultrasound

Shoulder pathologies of the rotator cuff of the shoulder are common in clinical practice. The focus of this pictorial essay is to discuss the anatomical details of the rotator interval of the shoulder, correlate the anatomy with normal ultrasound images and present selected pathologies. We focus on the imaging of the rotator interval that is actually the anterosuperior aspect of the glenohumeral joint capsule that is reinforced externally by the coracohumeral ligament, internally by the superior glenohumeral ligament and capsular fibers which blend together and insert medially and laterally to the bicipital groove. In this article we demonstrate the capability of high-resolution musculoskeletal ultrasound to visualize the detailed anatomy of the rotator interval. MSUS has a higher spatial resolution than other imaging techniques and the ability to examine these structures dynamically and to utilize the probe for precise anatomic localization of the patient's pain by sono-palpation.

Correlations of coracohumeral ligament and range of motion restriction in patients with recurrent anterior glenohumeral instability evaluated by magnetic resonance arthrography

BACKGROUND

Evaluation of range of motion (ROM) restriction before treatment of shoulder disorders is important for predicting the final functional outcomes. The purpose of this study was to investigate correlations of thickness of the coracohumeral ligament (CHL) and ROM restriction in patients with recurrent anterior glenohumeral instability.

METHODS

Between January 2005 and March 2015, 181 shoulders (137 male and 44 female patients; mean age, 29.3 years) with recurrent anterior glenohumeral instability treated with an arthroscopic Bankart repair were enrolled in this study. We evaluated preoperative ROM, thickness of the CHL, and obliteration of the subcoracoid fat triangle on magnetic resonance arthrography. ROM measurements, including forward flexion (FF), external rotation with the arm at the side (ER), and hand behind the back (HBB), were made in a standing position.

RESULTS

There were significant negative correlations between FF and age (P < .001) and between HBB and age (P < .001) but not between ER and age (P = .11). The thickness of the CHL significantly increased with age (P < .001). FF, ER, and HBB were significantly restricted in patients with obliteration compared with those without obliteration (P < .001, P = .004, P < .001, respectively).

CONCLUSIONS

Obliteration of the subcoracoid fat triangle and the thickness of the CHL positively correlated with ROM restrictions, and these changes were greater with age in patients with recurrent anterior glenohumeral instability.

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.

All-Arthroscopic Modified Rotator Interval Slide for Massive Anterosuperior Cuff Tears Using the Subdeltoid Space: Surgical Technique and Early Results

BACKGROUND

Traditional intra-articular arthroscopic repair techniques for massive anterosuperior rotator cuff tears are technically demanding and necessitate sacrifice of the rotator interval to enable visualization. An interval slide allows mobilization through release of the medial aspect of the rotator interval, while leaving the lateral, bridging fibers intact.

QUESTIONS/PURPOSES

The purpose of this study was to report a novel, arthroscopic, open-equivalent technique using the subdeltoid space to address these tears along with early clinical results.

METHODS

A retrospective review of prospectively collected data identified 11 consecutive arthroscopic massive anterosuperior rotator cuff repairs with a concomitant biceps tenodesis performed by the senior surgeon using a uniform technique. Outcome measures included range of motion, visual analog scale for pain, rotator cuff strength, American Shoulder and Elbow Surgeons (ASES) outcome scale, and Short Form-12 (SF-12).

RESULTS

Average length of follow-up was 22.2 months (range 12.5-30.0 months). Visual analog scale (VAS) pain scores, ASES, and SF-12 all demonstrated significant improvement from pre-op to final follow-up from 6.2 to 0.9 (p < 0.05), 27.4 to 82.8 (p < 0.05), and 26.6 to 45.5 (p < 0.05) respectively. Average forward flexion improved from 145° to 160° (p < 0.05). Seven of the nine patients with a positive preoperative belly press had a negative test at final follow-up. Nine of the 10 patients with a positive lift off test demonstrated a negative test on final follow-up. Ninety-one percent reported they were satisfied with their outcome.

CONCLUSIONS

The described modified all-arthroscopic subdeltoid approach for anterosuperior cuff repairs enabled an open-equivalent interval slide technique that preserved the bridging lateral fibers of the rotator interval and demonstrated promising early-term clinical results.

The Hidden Lesion of the Subscapularis: Arthroscopically Revisited

The "hidden lesion" refers to a tear of the subscapularis in the presence of an intact biceps pulley or rotator interval. Visualization of these tears during open surgery is difficult, yet even with the advancement of arthroscopy, visualization can still be challenging. Incomplete visualization of the subscapularis could lead to failure to diagnose a tear of the tendon and subsequently hinder results after shoulder surgery. With the advancement of arthroscopy, a technique to identify these hidden lesions is needed to avoid inferior results. We describe an arthroscopic technique to visualize, diagnosis, and repair these tears when clinically indicated. Implementing this technique in the setting of suspected subscapularis tendon injury can provide complete visualization of the tendon insertion.

Scapula behavior associates with fast sprinting in first accelerated running

The arm-swing motion is important for coordinated lower limb movement during a fast sprint and is composed of three-dimensional scapulothoracic and glenohumeral joint motion. Here, we aimed to clarify the role of the scapula during the initiation of a sprint running when sprinter run with high horizontal acceleration. Ten sports-active students participated in four 5-m dashes, with scapular constraint using non-elastic therapy tape (constraint condition) and without scapular constraint (free condition). The sprinting kinematics was assessed by a 16-camera motion capture system. In the constraint condition, the 2-m sprint time was significantly longer than that in the free condition. At the instants of foot-contact and take-off during the first step, no significant difference in the humerothoracic flexion angle was seen between these two conditions. In contrast, at the instants of foot-contact and take-off during the first step, the humerothoracic extension angle in the constraint condition was significantly smaller than that in the free condition. The forward leaning vector angle of center of mass during the first step was significantly greater than that in the constraint condition. Although no significant difference in hip extension and foot forward leaning angles was seen at the instant of foot contact during the first step between the two conditions, at the instant of take-off, the hip extension and foot forward leaning angles in the constraint condition were significantly smaller than those in the free condition. Therefore, scapular behavior in first accelerated running contributes to larger upper- and lower-limb motions and facilitates coordinating whole-body balance for a fast sprint.

A Thickened Coracohumeral Ligament and Superomedial Capsule Limit Internal Rotation of the Shoulder Joint: Report of Three Cases

Adhesive capsulitis of the shoulder (also known as frozen shoulder) is a painful and disabling disorder with an estimated prevalence ranging from 2% to 5% in the general population. Although the precise pathogenesis of frozen shoulder is unclear, thickened capsule and coracohumeral ligament (CHL) have been documented to be one of the most specific manifestations. The thickened CHL has been understood to limit external rotation of the shoulder, and restriction of internal rotation of the shoulder has been believed to be related to posterior capsular tightness. In this paper, three cases of refractory frozen shoulder treated through arthroscopic release of a contracted capsule including CHL were reported. Two cases in which there is recalcitrant severe restriction of internal rotation after manipulation under anesthesia (MUA) were finally treated with arthroscopic surgery. Although MUA could release the posterior capsule, internal rotation did not improve in our cases. After release of the thickened CHL, range of motion of internal rotation was significantly improved. This report demonstrates the role of the thickened CHL in limiting the internal rotation of the shoulder. We highlight the importance of release of thickened CHL in addition to the pancapsular release, in case of severe limitation of internal rotation of shoulder.

Combined Subscapularis Tears in Massive Posterosuperior Rotator Cuff Tears: Do They Affect Postoperative Shoulder Function and Rotator Cuff Integrity?

BACKGROUND

Previous studies on massive rotator cuff tears have not addressed the outcomes of tears extending to the subscapularis tendon.

HYPOTHESIS

The retear rate in patients with a massive posterosuperior rotator cuff tear combined with a subscapularis tear is higher than that in patients with a massive posterosuperior rotator cuff tear with an intact subscapularis tendon.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were collected and analyzed from 92 consecutive patients who underwent arthroscopic repair of a massive posterosuperior rotator cuff tear. Patients were divided into 3 groups according to the status of the subscapularis tendon: intact subscapularis tendon (I-massive tear; n = 42), tear involving half or less than half of the subscapularis tendon (S-massive tear; n = 22), and tear involving more than half of the subscapularis tendon (L-massive tear; n = 28). The integrity of the rotator cuff was determined by ultrasonography at 4.5 and 12 months or later after surgery. Clinical evaluations were performed using the visual analog scale (VAS) pain score, the American Shoulder and Elbow Surgeons (ASES) score, the Constant score, and active shoulder range of motion. Data were collected on the day before surgery and at final follow-up (at least 24 months postoperatively).

RESULTS

A total of 25 retears (27%) were identified based on an ultrasonographic evaluation. Although statistical significance was not found, there was a trend toward a higher retear rate in patients with an L-massive tear (43%) compared with those with an S-massive tear (18%; P = .050) or I-massive tear (21%; P = .059) at final follow-up. The subclassification of retears according to the involved tendons revealed that subsequent retears of the subscapularis tendon were noted only in patients with an L-massive tear. In patients with an L-massive tear, postoperative data comparison between patients with intact subscapularis tendons and those with failed subscapularis tendons revealed that a significant difference was noted in the VAS (1.1 vs 3.8, respectively) and ASES (90.6 vs 58.5, respectively) scores. The improvement in clinical scores after repair was statistically significant in all groups but not different between the groups.

CONCLUSION

The arthroscopic repair of massive tears results in substantial improvements in shoulder function, regardless of the presence of combined subscapularis tears. However, this study showed a trend toward a high failure rate for the repair of massive posterosuperior rotator cuff tears extending over half of the subscapularis tendon. Therefore, other treatment options should also be considered for this type of rotator cuff tear.

Elasticity of the Coracohumeral Ligament in Patients with Adhesive Capsulitis of the Shoulder

PURPOSE

To evaluate the elasticity of the coracohumeral ligament (CHL) in healthy individuals and patients with clinical findings suggestive of unilaterally involved adhesive capsulitis of the shoulder (ACS).

MATERIALS AND METHODS

The institutional review board approved this single-institution prospective study, which was performed between November 15, 2012, and July 8, 2014. Informed consent was obtained from all subjects. Measurement of CHL thickness was performed in the axial oblique plane under shoulder maximal external rotation. Shear-wave elastography (SWE) was used to evaluate elasticity of the CHL in healthy individuals (11 men, 19 women aged 22-62 years) and those with clinical findings suggestive of ACS (nine men, 11 women aged 41-70 years). SWE was performed in the shoulder-neutral position and under maximal external rotation. The Wilcoxon signed-rank test was performed to compare the thickness and elastic modulus of the CHL between bilateral shoulders.

RESULTS

In all subjects, the CHL elastic modulus was larger under maximal external rotation than in the neutral position (P < .001 for all). For healthy subjects, there was no significant difference in the CHL elastic modulus between the dominant and nondominant shoulders. For patients presumed to have ACS, the CHL thickness was significantly greater in the symptomatic shoulder than in the unaffected shoulder (P < .001). The CHL elastic modulus of the symptomatic shoulder (median, 234.8 kPa; interquartile range [IQR], 174.4-256.7 kPa) was significantly greater than that of the unaffected shoulder (median, 203.3 kPa; IQR, 144.1-242.7 kPa) in the shoulder-neutral position (P = .004) but not under maximal external rotation (P = .123). When bilateral shoulders were maintained at the same angle of external rotation, the CHL elastic modulus was greater in the symptomatic shoulder than in the unaffected shoulder (P = .005).

CONCLUSION

In patients with clinical findings suggestive of ACS, SWE showed that the CHL is stiffer in the symptomatic shoulder than in the unaffected shoulder.