The subcoracoid distance is correlated with pain and internal rotation after reverse shoulder arthroplasty.

Background: A proposed etiology of anterior shoulder pain and limited internal rotation after reverse shoulder arthroplasty (RSA) is impingement of the humeral component on the coracoid or conjoint tendon. The primary goal of this study was to investigate radiographic surrogates for potential coracoid or conjoint tendon impingement and their relationship to postoperative pain and internal rotation after RSA. Methods: A retrospective review of a clinical registry was performed to identify patients with (1) primary RSA, (2) minimum 2-year clinical follow-up, and (3) satisfactory postoperative axillary lateral radiographs. The primary radiographic measurement of interest was the subcoracoid distance (SCD), defined as the distance between the posterior aspect of the coracoid and the anterior glenosphere. Additional measurements were as follows: anterior glenosphere overhang, posterior glenosphere overhang, native glenoid width, lateralization of glenosphere relative to the coracoid tip, lateralization shoulder angle, and distalization shoulder angle. The primary clinical outcome of interest was the 2-year postoperative Visual Analog Scale score. Secondary outcomes were (1) internal rotation (IR) defined by spinal level (IRspine), (2) IR at 90 degrees of abduction, (3) American Shoulder and Elbow Surgeons score, (4) forward flexion, and (5) external rotation at 0 degrees of abduction. Linear regression analyses were used to evaluate the relationship of the various radiographic measures on the clinical outcomes of interest. Results: Two hundred seventeen patients were included. There was a statistically significant relationship between the SCD and Visual Analog Scale scores: B = -0.497, P = .047. There was a statistically significant relationship between the SCD and IRspine: B = -1.667, P < .001. Metallic lateralization was also positively associated with improving IRspine; increasing body mass index was negatively associated. There was a statistically significant relationship between the SCD and IR at 90 degrees of abduction: B = 5.844, P = .034. Conclusion: For RSA with a 135° neck shaft angle and lateralized glenoid, the postoperative SCD has a significant association with pain and IR. Decreasing SCD was associated with increased pain and decreased IR, indicating that coracoid or conjoint tendon impingement may be an important and potentially under-recognized etiology of pain and decreased IR following RSA. Further investigations aimed toward identifying a critical SCD to improve pain and IR may allow surgeons to preoperatively plan component position to improve clinical outcomes after RSA.

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.

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.

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.

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.

Morphology of the coracoid process as a predictor of articular-side tear at the upper border of the subscapularis.

BACKGROUND: Articular-side tear at the upper border of the subscapularis (SSC-AST) is often detected during shoulder arthroscopic surgery, although its exact pathology remains unknown. The purpose of this study was to investigate the correlation between various characteristics of the coracoid process, including classification of the morphology of the coracoid process tip, and the presence of SSC-AST. METHODS: This retrospective, case-controlled study included patients who underwent arthroscopic subacromial decompression with or without rotator cuff repair between January 2018 and September 2021. A total of 130 shoulders in 124 patients, including 77 male and 53 female shoulders (mean age at surgery, 64 years [range, 39-88 years]), were included in this study. Three-dimensional (3D) computed tomography examination was performed preoperatively, and the following indices were measured: coracoid proximal length, coracoid distal length, coracoid angle, coracoglenoid angle, offset of the coracoid process and glenoid (anterior, lateral, and superior offset), and coracoid base angle. The morphology of the tip of the coracoid process was classified into 3 types according to 3D reconstructed views: flat type, round type, and beak type. The presence of SSC-AST was intraoperatively evaluated arthroscopically via a posterior glenohumeral portal. Morphologic risk factors for SSC-AST were evaluated between SSC-AST cases (group T) and non-SSC-AST cases (group N) by multivariable logistic analysis. In addition, the correlation between the incidence of SSC-AST and classification of the tip of the coracoid process was analyzed. RESULTS: SSC-AST was present in 53 shoulders (40.8%). Group T patients were significantly older than group N patients (68.4 ± 10.0 years vs. 61.5 ± 11.8 years, P < .001). No sex difference was detected between the 2 groups (28 male and 25 female shoulders in group T vs. 49 male and 28 female shoulders in group N, P = .28). Multivariate analysis of morphologic parameters between the 2 groups detected a smaller superior offset as a risk factor for SSC-AST (odds ratio, 0.91; 95% confidence interval, 0.84-0.98; P = .01). No significant differences were found in the other parameters. Regarding classification of the tip of the coracoid process, round- and beak-type coracoid tips had a significantly higher rate of SSC-AST than flat-type tips (flat type, 21.8%; round type, 64.7%; and beak type, 46.3%) (P < .001). CONCLUSIONS: Evaluation of the correlation between the morphology of the coracoid process on 3D computed tomography and the presence of SSC-AST visualized during arthroscopy indicated a significant association between SSC-AST and the morphology of the coracoid process.

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.

Anterior shoulder anatomy and subcoracoid impingement: An anatomical study.

OBJECTIVE: The aim of our study was to describe the anatomy of the anterior shoulder, specifically structures potentially involved in subscapularis tears pathophysiology and also to identify structures at risk during surgical approaches of this area. MATERIALS AND METHODS: We designed an observational, experimental study based on cadaveric models. Dissection was performed and several structures of the anterior shoulder were characterized including the subscapularis, coracoid morphology, the coracoacromial ligament, coraco-humeral distance, and the axillary and musculocutaneous nerves. RESULTS: Our sample included 16 shoulders. The coracoacromial ligament presented two bands in 37.5%, and these variants were significantly wider and thinner, and were associated with inferior coraco-humeral distance in internal rotation. The subscapularis footprint was longer and the coracoid process was bigger in male specimens, and the median coracoid angle was 122°, corresponding to a Leite-Torres type I. The Subscapularis showed a median thickness of 0.7cm, while the coraco-humeral distance in our sample ranged from 0.30cm in internal rotation to 0.85cm in external rotation. Neurologic relevant structures were at least more than 2.55cm from the coracoid tip. CONCLUSIONS: This is the first paper to explore the eventual relationship between the presence of a double band coracoacromial ligament variant and subcoracoid impingement. Also, to our knowledge, this is the first cadaveric model study to postulate a possible anatomic base for subcoracoid impingement, as the SS myotendinous junction thickness was found to be greater than the coraco-humeral distance in neutral position and in IR.

Coracoid morphology and humeral version as risk factors for subscapularis tears.

BACKGROUND: The pathophysiology of subscapularis (SS) lesions is still relatively unknown despite recent interest in predictive factors for SS tears. Our goal was to determine the influence of the coracoid morphology and humeral version on SS tears. METHODS: This was a retrospective, controlled, single-blinded study. We analyzed 232 shoulders with SS lesions confirmed by magnetic resonance imaging. The coracoid proximal length, coracoid distal length (CLD), and coracoid total length were measured. The coracoid length ratio, coracoid angle (CA), and humeral version were also evaluated. RESULTS: We found that greater humeral retroversion was progressively related to more serious SS injuries, with values of -28.6° ± 19.5° and -51.0° ± 11.1° in the normal SS group and tear group, respectively (P < .001). The same tendency was shown for the CA, with values of 123.8° ± 11.1° in the control group vs. 97.4° ± 10.1° in the tear group (P < .001). Greater CLD, coracoid total length, and coracoid length ratio were also associated with an increased risk of SS tears (P < .001). The CA and CLD represented the best predictors of SS tears, presenting areas under the receiver operating characteristic curve of 90.0% and 89.0%, respectively. CONCLUSIONS: This article is the first to study the influence of different parameters of the coracoid process morphology and humeral version on SS tears. We proved that humeral version and coracoid morphology were important risk factors for SS pathology and could accurately predict these lesions. Finally, our study was the first to create a classification system to divide coracoids according to their morphology and relative risk of associated SS tears.

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 <60o to reduce potential impingement.

Coracohumeral distance and coracoid overlap as predictors of subscapularis and long head of the biceps injuries.

BACKGROUND: Subscapularis (SS) lesions are often underdiagnosed because of an incomplete understanding of contributing factors but also because of a greater difficulty in SS tear diagnosis with magnetic resonance imaging or physical examination. In this setting, predicting factors can be useful tools in these injuries' management. The goal of this study was to determine the influence of the coracohumeral distance (CHD) and coracoid overlap (CO) in anterior rotator cuff lesions, as well as to determine the CHD and CO values that can accurately predict SS and long head of the biceps (LHB) injuries. METHODS: We performed a retrospective, controlled, single-blinded study. We analyzed 301 patients with rotator cuff pathology and magnetic resonance imaging studies; patients with SS lesions represented the study group. The CHD and CO were measured. RESULTS: We found that lower CHD and higher CO values were progressively related to more serious injuries of the SS and LHB. The CHD was a very strong predictor of SS injury and tear and a good predictor of LHB injuries. A CHD of 7.6 mm had a sensitivity of 84.4% and specificity of 88.6% for SS tears. The CO was also a very strong predictor of SS tears and a good predictor of LHB injury, with a CO of 16.6 mm reaching a sensitivity of 77.8% and specificity of 68.3% for SS tears. CONCLUSIONS: The CHD is an excellent predictor of SS tears and a good predictor of LHB lesions, with the CO also being a very strong predictor of SS tears and a good model for LHB injuries.

Estudio comparativo de la distancia coracohumeral en pacientes con patología degenerativa del subescapular y una población voluntaria asintomática / Comparative analysis of the coracohumeral distance between patients with degenerative subscapularis tendon pathology and a normal age-matched population

INTRODUCCIÓN: El pinzamiento subcoracoideo secundario a una distancia coracohumeral (DCH) disminuida, ha sido descrito como una posible etiología de las lesiones degenerativas del tendón del Subescapular (SSC), sin embargo, esa teoría aún es controversial. OBJETIVO: Evaluar si existe una diferencia significativa entre la DCH promedio de pacientes con patología degenerativa del SSC y un grupo control. MATERIALES Y MÉTODOS: Se diseñó un estudio de casos-controles y se estableció un tamaño muestral mínimo de 36 casos por grupo. De nuestra base de datos, y dentro de un periodo de 6 meses, se rescataron 46 Resonancias Magnéticas (RM) de hombro con patología degenerativa avanzada y/o roturas del SSC (grupo SSC). El grupo control fue conformado por 36 RM realizadas a voluntarios asintomáticos sin patología del mango rotador. Se incluyeron en ambos grupos solo pacientes entre 40 y 60 años. Se utilizó prueba de t para determinar las diferencias entre 2 grupos con un nivel de confianza del 95%. RESULTADOS: La edad promedio del grupo SSC fue 50,1 6,1 años y del grupo control 51,7 6,8 años, no existiendo diferencia estadísticamente significativa entre ambos (p » 0.43). La DCH promedio en el grupo SSC fue 8,58 mm [IC: 7,95­9,21 mm], y en el grupo control fue 11,04 mm [IC: 10,05­12,04 mm]. Al comparar la DCH, se encontró una diferencia estadísticamente significativa entre grupos (p » 0,00048). CONCLUSIÓN: Nuestros resultados respaldan la existencia de una asociación estadísticamente significativa entre una DCH disminuida y la presencia de patología degenerativa del SSC. NIVEL DE EVIDENCIA: III (Estudio de casos y controles).

BACKGROUND: The incidence of subscapularis tears is increasing as diagnostic imaging and arthroscopic technology improves. Decreased coracohumeral distance (CHD) with associated Subcoracoid Impingement is thought to be one, potential etiology for these lesions. OBJECTIVE: The purpose of this study was to identify the association between reduced CHD and degenerative pathology of the subscapularis tendon. METHODS: A comparative case-control study was performed. The sample size required to determine significance was calculated to be 36 cases. In total, 46 patients with severe degenerative SSC tendinopathy or subscapularis tears on magnetic resonance imaging (MR) were collected consecutively from our database (SSC group). The control group consisted of 36 asymptomatic volunteers undergoing shoulder MR. Only patients between 40 and 60 years of age were included. An independent t-test was used to determine the statistical significance between the two groups (with a 95% level of confidence). RESULTS: No statistically relevant difference was found between the average age of the two groups (50.1 6.1 and 51.7 6.8; p » 0.43). In the control group, the mean CHD was found to be 11.04 mm [CI:10.05­12.04 mm] and was 8.58 mm [CI: 7.95­9.21 mm] in the subscapularis group. The statistical analysis, comparing the CHD showed a significant difference between groups (p » 0.00048). CONCLUSION: This study supports the conclusion that degenerative subscapularis pathology is associated with narrowed coracohumeral distance, when compared with an asymptomatic age-matched group. LEVEL OF EVIDENCE: III (case-control study).

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.

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.

Idiopathic heterotopic ossification of bilateral subscapularis tendons: illustration of a rare entity and a concise literature review.

Ossification of the subscapularis tendon is an extremely uncommon, poorly described lesion with little known about its etiopathogenesis and clinical significance. To the best of our knowledge, only three cases of this entity have been reported till now, which were all unilateral. The authors present first case of ossification of bilateral subscapularis tendons in a 57-year-old male and hope that with increase in the number of reported cases, proper guidelines for management of such cases can be formulated.

Subcoracoid impingement and subscapularis tendon: is there any truth?

Subcoracoid impingement and stenosis have been described related to anterior shoulder pain and subscapularis tendon tears, but the pathogenesis and related treatment of this condition has still not been explained properly. Variability of coracoid morphology has been described and both traumatic and iatrogenic factors can modify it. Some authors referred this to a primary narrow coracohumeral distance with different threshold values defined as increased risk factor for subscapularis and antero-superior RC tear; opposite theories stated that the stenosis is secondary to an anterosuperior translation of the humeral head toward the coracoid due to degenerative changes of the rotator cuff tendons. Limited coracoplasty can be performed when related risk factors are identified; however no clear consensus arises from specific literature review and extensive clinical and instrumental examination of the patient should be performed in order to identify specific risk factors for subscapularis tendon pathology and, subsequently, tailor the proper approach.

Coracohumeral Distances and Correlation to Arm Rotation: An In Vivo 3-Dimensional Biplane Fluoroscopy Study.

BACKGROUND: Reduced coracohumeral distances have been reported to be associated with anterior shoulder disorders such as subscapularis tears, biceps tendon injuries, and leading edge supraspinatus tears. PURPOSE: To determine the variability in coracohumeral distance as a function of arm rotation in healthy male subjects. The null hypothesis was that no differences in coracohumeral distance would exist with respect to arm rotation. STUDY DESIGN: Descriptive laboratory study. METHODS: A total of 9 male participants who had full range of motion, strength, and no prior surgery or symptoms in their tested shoulders were enrolled in this institutional review board-approved study. Computed tomography scans of the shoulder were obtained for each subject. A dynamic biplane fluoroscopy system recorded internal and external shoulder rotation with the arm held in the neutral position. Three-dimensional reconstructions of each motion were generated, and the coracohumeral distance and coracoid index (lateral extension of the coracoid) were measured. RESULTS: The mean coracohumeral distance in neutral rotation was 12.7 ± 2.1 mm. A significantly shorter minimum coracohumeral distance of 10.6 ± 1.8 mm was achieved (P = .001) at a mean glenohumeral joint internal rotation angle of 36.6° ± 19.2°. This corresponded to a reduction in coracohumeral distance of 16.4% (range, 6.6%-29.8%). The mean coracoid index was 14.2 ± 6.8 mm. A moderate correlation (R = -0.75) existed between the coracohumeral distance and coracoid index. CONCLUSION: Coracohumeral distance was reduced during internal rotation. Decreased coracohumeral distance was correlated with larger coracoid indices. CLINICAL RELEVANCE: This study provides a reference value for coracohumeral distance in the healthy male population. Knowledge of how coracohumeral distance varies over the range of arm internal-external rotation may improve the clinical diagnosis and treatment plan for patients with anterior shoulder pathology, specifically subcoracoid impingement. Imaging of the coracohumeral distance during internal rotation with the hand at approximately midline should be considered to assess patients with anterior shoulder pain.

Shoulder impingement syndromes: implications on physical therapy examination and intervention.

A painful shoulder presents challenges in examination, diagnosis and intervention for the physical therapist because of the complexity of the structures involved. A common cause of shoulder pain is shoulder impingement syndrome. This was first described as a condition in which the soft tissues of the subacromial space were chronically entrapped and compressed between the humeral head and the subacromial arch. This definition does not account for the myriad potential causes of shoulder impingement conditions, as forms of impingement other than subacromial soft tissue compression may explain different symptomatic shoulder injuries. This paper describes shoulder impingement syndromes that have been hypothesized, identified and analyzed in the literature. Physical Therapy examination and intervention for these syndromes are also discussed.