Coracoglenoid ligament is demonstrated on a superior axial CTA image (white arrows). Glenoid labrum Definition & Meaning | Merriam-Webster Medical There are several bursae around the shoulder, the most important being the subacromial, subdeltoid, subscapular, and subcoracoid bursae (Figure 13, additional material). Coronal oblique PD-weighted MR image depicts the normal attachment of the tendon of the deltoid muscle visible on one single section mimicking an enthesophyte (arrow). . It relies on ligaments and muscle tendons to provide reinforcement. On cross-section, the labrum can be triangular (more commonly) or round 4. The scapulohumeral and thoracohumeral muscles are responsible for producing movement at the glenohumeral joint. Axial CT arthrography through the acromioclavicular joint demonstrates an os acromiale (arrow) with synchondrosis (arrowhead). The anterior band limits externalrotation of the arm, while the posterior band limits internalrotation. Anteriorly: superior glenohumeral ligament; middle glenohumeral ligament (variably), Inferiorly: inferior glenohumeral ligament consistenting of an anterior band, axillary pouch, and a posterior band. They can extend into the tendon, involve the glenohumeral ligaments or extend into other quadrants of the labrum. The connection between the rotator cable and rotator cuff tendons is tight and confirms the suspension bridge theory for rotator cuff tears in most areas between the supraspinatus tendon and rotator cable. The suprascapular nerve traverses posteriorly the suprascapular fossa through the suprascapular notch. Edinburgh: Elsevier Churchill Livingstone. Initial descriptions of the location of the foramen stated that it should not extend below the level of the midglenoid notch that is present at the physeal line or junction of the superior and middle thirds of the glenoid; however, Tuite and colleagues noted that in some patients a sublabral foramen may extend below the midglenoid notch. Two orthogonal views (anteroposterior and lateral views) of any bone or joint should be ideally obtained. The presence of high origin of the anterior band of the IGHL was recently reported as a potential imitator of sublabral foramen. This variant is encountered in about 11% of individuals and best seen on fat-saturated T1-weighted coronal oblique images obtained with MRA and CTA (Figure (Figure14)14) [13]. : a fibrocartilaginous ligament forming the margin of the glenoid cavity of the shoulder joint that serves to broaden and deepen the cavity and gives attachment to the long head of the biceps brachii. In the acute setting, they are most frequently seen in . The comprehensive textbook of clinical biomechanics (2nd ed.). This space contains the scapular circumflex artery (Figure 3, additional material) [1,2]. shallow glenoid fossa and hypoplasia of the lower two-thirds of the glenoid and scapula neck with irregular joint surface 2, Walch classification can be used in assessing glenoid wear, ADVERTISEMENT: Supporters see fewer/no ads, Please Note: You can also scroll through stacks with your mouse wheel or the keyboard arrow keys. Physiopedia is not a substitute for professional advice or expert medical services from a qualified healthcare provider. The subscapular recess is located between the coracoid process superiorly and the superior margin of the subscapularis tendon. You will appreciate timely appointments and a professional, friendly atmosphere where we take time to listen to your . 12 Glenoid labrum - Wikipedia The inferior transverse scapular ligament (spinoglenoid ligament) forms the roof of the notch. Philadelphia, PA: Saunders. Magnetic resonance arthrography (MRA) is especially useful in the diagnosis of labral and ligamentous pathology.4 In determining the difference between a labral tear and a GAGL lesion, imaging can be difficult to interpret, leaving arthroscopy as the definitive diagnostic tool. CT and MR arthrography of the normal and pathologic anterosuperior labrum and labral-bicipital complex, MR arthrography of the glenohumeral joint. 2000;20 Spec No(suppl_1):S67-81. In a type I BLC, the labrum is firmly attached to the glenoid rim, with no intervening cartilage or central free edge. [1] [2] See Shoulder Instability, Get Top Tips Tuesday and The Latest Physiopedia updates, The content on or accessible through Physiopedia is for informational purposes only. A shallow contrast-filled cleft can sometimes be depicted between the labrum and the biceps, the so-called bicipital labral sulcus ( Fig. An example of different MRA pulse sequences is represented in Table Table33. Main points of study: Conclusion: Physical examination is more accurate in predicting glenoid labral tears than magnetic resonance imaging. Blood supply and vascularity of the glenoid labrum: Its clinical Burkhart and colleagues reported its consistent location at the central aspect of the inferior glenoid and noted that it provided a useful landmark at arthroscopy to quantify the degree of glenoid bone loss. (A) Anteroposterior (AP) view with external rotation; (B) AP with internal rotation; (C) AP with neutral arm position; (D) Lateral view of scapula or Y view; (E) Axillary view. http://journals.sagepub.com/doi/abs/10.1177/036354659602400205, http:///index.php?title=Glenoid_Labrum&oldid=324941. The labrum demonstrates its greatest variation in morphology and attachment above the equator. Clinical assessment of the glenoid labrum - PMC - National Center for The joints capsular pattern is externalrotation, followed by abduction, internal rotation and flexion. Provides insertion for stabilizing structures, as a fibrous crossroad, with the labrum and. Previous reports have shown the labrum to be predominantly composed of fibrous tissue with some fibrocartilaginous components at the chondrolabral junction. Shoulder Joint Tear (Glenoid Labrum Tear) - OrthoInfo - AAOS Analysis of consecutive coronal oblique MR images is necessary to avoid misinterpretation. The sublabral sulcus or recess present in type II and III BLCs represents the most frequent normal anatomic variant of the superior labrum. 2008; Smith et al . At the time the article was last revised Henry Knipe had the following disclosures: These were assessed during peer review and were determined to Articular congruity of the glenohumeral joint is improved by normal alterations in the cartilage thickness. Cystic lesions in the posterosuperior bare area of the humeral head should not be mistaken for degenerative sequels or vascular channels. The rotator cable or ligamentum semicircular humeri is a band-like fibrous thickening that extends in an oblique direction from the coracohumeral ligament along the articular surface of the supraspinatus fibers anteriorly. {"url":"/signup-modal-props.json?lang=us"}, Goel A, Knipe H, Weerakkody Y, et al. The scapula is a triangular bone which consists of the scapular body, the scapular spine, the scapular neck, the acromion, the glenoid fossa and the coracoid process. The authors have no competing interests to declare. Magee, D. J. Thus, the aim of this study was to state the prevalence . The combination of an absent anterosuperior labrum and a thickened cordlike MGHL is termed the Buford complex; this is a relatively uncommon normal variant, occurring in approximately 1.5% of patients ( Fig. An improved understanding of normal anatomy, biomechanics, and variants will help to avoid potential pitfalls in the interpretation of noncontrast and arthrographic shoulder MR imaging examinations. MR images are obtained with a dedicated shoulder coil at 1.5 or 3 Tesla. In the shoulder joint, the head of the humerus (upper arm bone) functions as the ball and the glenoid cavity of the scapula functions as the socket. A posterior labral tear (reverse Bankart) is also present (arrowhead), and a bone bruise is seen within the . Understanding the Glenoid Avulsion of the Glenohumeral - ScienceDirect In this case, there is a communication between the synchondrosis and the glenohumeral joint (with high-density contrast penetration), which is not normal. The shoulder anatomy provides mobility but leads to a relatively unstable joint, prone to subluxation and dislocation [2]. External rotation of the humerus moves the greater tubercle out from under the acromial arch, allowing uninhibited arm abduction to occur. and grab your free ultimate anatomy study guide! The inferior border of the rotator interval is formed by the middle glenohumeral ligament [6,14]. An additional posterolateral portal was created at the midportion between the posterior and anterosuperior portals for suture anchor insertion to the posterior glenoid. Recent work has expanded their anatomic description for the inferior but also superior glenohumeral ligament complexes. 1 ). The coracoacromial ligament is the ligamentous compound of the coracoacromial arch. The subscapularis muscle arises from the subscapular fossa of the anterior face of the scapula and attaches to the lesser tuberosity. Three types of biceps labral complex (bicipital anchor) have been described. Two weak spots exist in this reinforced capsule. (A) Schematic illustration of the anterior ligaments of the shoulder. A bare area of the glenoid misdiagnosed as a cartilage ulceration, Morphology of the acromion and its relationship to rotator cuff tears. St. Louis: Elsevier Saunders. The two last posterior glenoid rim variants can be associated with varying degrees of posterior shoulder instability due to loss of concavity of the inferior glenoid margin. The FADIR position is achieved by placing the patients arm across the chest with the hand on the contralateral shoulder. Awareness and understanding of the complex anatomy of the shoulder articulation and the ability to recognize normal anatomic variants and potential imaging pitfalls are critical to accurate interpretation of conventional and arthrographic MR imaging studies. The supraspinatus muscle arises from the supraspinous fossa along the dorsal scapula. These bursae allow the structures of the shoulder joint to slide easily over one another. Under normal circumstances this bursa does not communicate with the joint space and is not seen on MRI unless it is distended by fluid. The inferior glenohumeral ligament is actually a complex of anterior and posterior bands as well as an axillary pouch that is reinforced by the fasciculus obliquus on the glenoid side (Figure (Figure16).16). Anterior capsulolabral insertion variance. It is delimited by the acromion, acromioclavicular joint, coracoid process, and the coracoacromial ligament. Glenohumeral joint: want to learn more about it? This morphological abnormality may lead to shoulder instability, accelerated osteoarthritis or posterior labral tears [3,6]. True cartilage defects of the humeral head are often located in the posterosuperior portion medial to the location of the bare area [3,5,6,7]. Subscapularis tendon (open arrow) and anterior labrum (arrowhead) are also shown on this section. The distal fibers of the supraspinatus, infraspinatus and teres minor extending lateral to the rotator cable and inserting into the greater tuberosity of the humerus, are called the rotator crescent. Focal thickening of the subchondral bone along the central aspect of the glenoid fossa is an additional normal variant termed the Ossaki tubercle. Diagnosis of glenoid labral tears: a comparison between magnetic resonance imaging and clinical examinations. The tendon of the short head of the biceps muscle is anterior to the humeral head. Read more. According to the cadaveric study of Gleason et al., there is no identifiable separate transverse humeral ligament. Superior Labral Lesions - Medscape At the capsuloligamentous level, the roof of this space is formed by the anterior part of the superior complex (the superior glenohumeral ligament and coracohumeral ligament). The additional accessory movements of spin, roll and slide (glide) are also available within the glenohumeral joint. The labrum is a cup-shaped rim of cartilage that lines and reinforces the ball-and-socket joint of the shoulder. Laterally, it fuses with the posterior part of the rotator cable and fibers of the infraspinatus before these three structures jointly insert on the posterior facet of the greater tuberosity. The glenoid or glenoid cavity/fossa is the shallow depression of the scapula found on the lateral angle. As for the tubercle of Assaki, the bare area of the glenoid may be mistaken for a cartilage ulceration. Gyftopoulos, S, Bencardino, J, Nevsky, G, et al. The sublabral recess is best seen with arthrographic technique. 5. The capsular mechanism provides the most important contribution to the stabilization of the glenohumeral joint. Kenhub. in internal & external rotation) [1]. Contrarily to benign hematopoietic marrow hyperplasia, those pathologies are characterized by very low signal intensities on T1-weighted images and an asymmetrical distribution bilaterally with epiphyseal involvement (Figure (Figure2)2) [6]. This should not be mistaken for a cartilage defect [3,4]. Reference article, Radiopaedia.org (Accessed on 28 Jun 2023) https://doi.org/10.53347/rID-27109, {"containerId":"expandableQuestionsContainer","displayRelatedArticles":true,"displayNextQuestion":true,"displaySkipQuestion":true,"articleId":27109,"questionManager":null,"mcqUrl":"https://radiopaedia.org/articles/glenoid-labrum/questions/2480?lang=us"}, see full revision history and disclosures, doi:10.1148/radiographics.20.suppl_1.g00oc03s67, medial (ulna) collateral ligament complex, lateral (radial) collateral ligament complex, accessory flexor digitorum superficialis indicis, accessory head of the flexor pollicis longus, superficial palmar branch of the radial artery, Radiopaedia Events Pty Ltd, Speaker fees (past), Integral Diagnostics, Shareholder (ongoing), inferiorly: inferior glenohumeral ligament consistenting of an anterior band, axillary pouch, and a posterior band, variable cross-sectional shape: blunted, cleaved, notched or flat. Get instant access to this gallery, plus: For a broader topic focus, try this customizable quiz. Purpose: Differentiating the anatomical variations of the anterosuperior portion of the glenoid labrum from pathologies is important to avoid unnecessary iatrogenic complications resulting from inaccurate diagnosis. This is a stabilizing mechanism in which compression of the humerus into the concavity of glenoid fossa prevents its dislocation by translating forces. Help in the provision of the Viscoelastic Piston effect. The inferior portion of the joint is also reinforced by fibers of the coracoacromial ligament, which blends with the undersurface of the capsule [2]. Glenoid Labrum Tear Treatment at Baptist Health: Our Approach. In that case the capsular recess can be prominent anteriorly and beneath the subscapularis tendon [3,4]. However, ultrasonographic evaluation of the shoulder is limited to the long head of biceps tendon, the rotator cuff, the subacromial-subdeltoid bursa and the acromioclavicular joint. 1/4 Synonyms: Glenoid cavity of scapula, Cavitas glenoidalis scapulae The glenohumeral joint is the articulation between the spherical head of the humerus and the concave glenoid fossa of the scapula. The coracoacromial arch is an osteoligamentous arch that protects the humeral head and rotator cuff tendons from trauma. To move and support the shoulder, different structures must work in synergy like muscles, tendons, ligaments, and cartilaginous structures. The labrum demonstrates considerable anatomic variability in its appearance, which may pose a diagnostic challenge to image interpretation. Activities of the arm rely on movement from not only the glenohumeral joint but also the scapulothoracic joint (acromioclavicular, sternoclavicular and scapulothoracic articulations). The labral outline is ovoid in configuration, conforming to the underlying glenoid rim, and is most firmly attached to the glenoid posteriorly and inferiorly. Awareness and understanding of the complex anatomy of the shoulder articulation and the ability to recognize normal anatomic variants and potential imaging pitfalls are critical to accurate interpretation of conventional and arthrographic MR imaging studies. The glenohumeral, or shoulder, joint is a synovial joint that attaches the upper limb to the axial skeleton. 5 ). Types 2 and 3 are classified according to the varying depth of the sublabral sulcus. 3, 9 SLAP lesions have also been identified in patients with full-thickness rotator cuff tears1 or glenohumeral instability. The main lateral rotators are the infraspinatus and teres minor muscles, with help from the posterior fibers of the deltoid muscle. It is best seen on axial images as a circular, signal void structure in the intertubercular groove. Torn Shoulder Labrum Symptoms & Treatments | HSS Orthopedics The glenoid labrum is a fibrocartilaginous complex that attaches as a rim to the articular cartilage of the glenoid fossa. Read more, Physiopedia 2023 | Physiopedia is a registered charity in the UK, no. Thus repositioning the glenohumeral joint, and upper limb, within space. For the anterior part, this is more variable. Individually, each muscle has its own pulling axis that results in a certain movement (prime mover), while together they create a concavity compression. Philadelphia, PA: Wolters Kluwer Health/Lippincott, Williams & Wilkins. Other disadvantages include ionizing radiation, invasiveness of injection procedure and the presence of metal artifacts in postoperative patients. The tendon passes within the joint superiorly and obliquely under the rotator cuff, between the supraspinatus tendon and the subscapularis tendon through the rotator interval. Of note, is that these muscles have a stronger action when acting to extend the flexed arm. Bare area of the glenoid on CTA. Conventional radiography of the shoulder [1]. Posteroinferior labrum: Reverse Bankart lesion; Posterior GLAD; Posterior labrocapsular periosteal sleeve avulsion lesion (POLPSA); Kim lesion (superficial tears between the posterior glenoid labrum and glenoid articular cartilage without labral detachment). Laterally, it fuses with the posterior part of the rotator cable and fibers of the infraspinatus tendon before these three structures jointly insert on the posterior facet of the greater tubercle (Figure (Figure20).20). The surface of the humeral head is three to four times larger than the surface of glenoid fossa, meaning that only a third of the humeral head is ever in contact with the fossa and labrum. Present in 11% of normal patients, the foramen represents a focal developmental detachment of the anterosuperior labrum, which may be confused with an anterior labral tear if care is not taken to note features of this anatomic variant ( Fig. It is a flat, gliding joint that gives the shoulder additional flexibility which is not possible with the glenohumeral joint alone. 3. Radiographics. Orthopedic physical assessment (6th ed.). The first is the rotator interval, an area of unreinforced capsule that exists between the subscapularis and supraspinatus tendons. With the administration of intra-articular contrast and distension of the joint, capsular apposition becomes less problematic. The subdeltoid-subacromial (SASD) bursa is located between the joint capsule and the deltoid muscle or acromion, respectively. The 12-o'clock position was the only location on the glenoid rim where the hyaline articular cartilage extended over the rim of the glenoid. glenoid labrum:the cavity has a fibrocartilaginous structure on its margin called the glenoid labrum which is continuous superiorly with the tendon of the long head of biceps brachii, joint capsule:attaches to the glenoid outside the glenoid labrum and tendon of the long head of biceps brachii, superior, middle and inferior glenohumeral ligaments:thickenings of the joint capsule. (A) Coronal oblique fat-suppressed T1-weighted MR arthrographic image shows a sublabral recess as an increased linear signal undercutting the contour of the superior glenoid labrum (arrows, A) following the contour of the glenoid cartilage without extension posterior to the biceps anchor. Torn Shoulder Labrum: Causes, Symptoms, Treatment, Recovery The glenohumeral joint is a ball-and-socket joint lying between the articulation of the rounded head of the humerus and the cup-like depression of the scapula, also called the glenoid fossa (Figures 13, additional material). Other investigators have since noted improved detection of anteroinferior labral pathology with the ABER technique. The middle glenohumeral ligament can be doubled as a normal variant. Subacromial pseudospur. Vossen, JA and Palmer, WE. 8 ). Together these three are known as the climbing muscles, as they are powerful adductors, alternatively they can lift the trunk up towards a fixed arm. Kwak and colleagues described the ABER position as optimal for evaluation of the IGHL and advocated it as an adjunct to routine imagingexamination. The dorsal aspect of the scapula is divided by the scapular spine into the supraspinous and infraspinous fossa where the supraspinatus and infraspinatus muscles attach respectively [3,6]. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License (CC-BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Made of fibrocartilage, 3 mm thick and 4 mm wide (highly variable). Trabecular bone has high or intermediate signal intensity on T1-weighted images. Anatomy and human movement: structure and function (6th ed.). Mischaracterization of this finding as a superior labral anterior-posterior (SLAP) II tear is a potential diagnostic pitfall. The use of ultrasound in the assessment of the glenoid labrum of the The subcoracoid bursa is located between the subscapularis muscle and the coracoid process, whereas the superior subscapular recess also known as the subscapular bursa is located between the anterior surface of the scapula and the subscapularis muscle (Figure 13, additional material). A superior-posterior facet was found consistently on the glenoid. The glenohumeral joint is innervated by the subscapular nerve (C5-C6), a branch of the posterior cord of brachial plexus. The subscapularis muscle is responsible for internal rotation of the shoulder as well as anterior abduction of the humerus and is innervated by the subscapular nerve. Philip Robinson. It is believed that the supraspinatus is important for movement initiation and early abduction, while the deltoid muscle is engaged from approximately 20 of abduction and carried the arm through to the full 180 of abduction. The border between the layers of cartilage and bone tissues was distinguished, and the point of abrupt change was defined as the bony edge (arrowhead; Fig. It comprises an osseous hypoplasia of the posteroinferior glenoid edge in the form of sloping and flattening and is associated with hypertrophy of the adjacent cartilage and labrum and with glenoid irregularity. In type II, the capsule attaches on the glenoid neck within 1 cm of the labral base. Indirect MRA performed after intravenous contrast injection is less invasive and expensive but lacks capsular distension and therefore is less accurate than direct MRA. Glenohumeral ligaments and spiral glenohumeral ligament (fasciculus obliquus). Glenoid. The second is on its superior and posterior aspects, where the capsular fibers blend directly with the glenoid labrum. The transverse humeral ligament is also intimately related to the biceps pulley (Figure 5, additional material). and transmitted securely. Type 3 corresponds to a large sublabral sulcus which extends under the labrum and over the cartilaginous portion of the glenoid fossa [3]. (B) Sagittal oblique PD-weighted MR arthrogram image shows the fasciculus obliquus (thick white arrows, B), the frenula capsulae (synovial bands) (thin white arrows, B) and the middle glenohumeral ligament (black arrows, B) can be identified on this sagittal section. The glenohumeral joint has a greater range of movement (RoM) than any other body joint. The shoulder labrum, also known as the glenoid labrum, is the attachment site for ligaments and provides support for shoulder joint as well as the rotator cuff tendons and muscles. These are the supraspinatus, infraspinatus, teres minor and subscapularis muscles. The subscapularis tendon inserts here in a broad band. Along with the infraspinatus, the teres minor muscle assists in external rotation of the shoulder and is innervated by the axillary nerve [4]. The superior acromioclavicular ligament extends from the upper acromion to the end of the clavicle. All content published on Kenhub is reviewed by medical and anatomy experts. Glenohumeral joint (Articulatio glenohumeralis) -Yousun Koh. The axillary pouch or recess has a U-shaped appearance on MRA or CTA when the inferior glenohumeral ligament is normal (Figures (Figures1212 and and23)23) [4,6,14,15]. It extends from the edge of the acromion, anterior to the articular surface of the acromioclavicular joint, to the lateral border of the coracoid process (Figure 7, additional material). Likewise, the superior capsule not only contains the superior glenohumeral ligament, the coracohumeral ligament, and the rotator cable but also the posterosuperior glenohumeral ligament as described by Pouliart et al., [14]. The shoulder joint is considered a ball and socket joint. Shoulder Surgery: Detached Labrum Repair - HSS Various muscle variants exist within the shoulder, including accessory biceps brachii muscle heads (described above), coracobrachialis brevis muscle, accessory subscapularis muscle, and the aberrant muscle bundle originating from the latissimus dorsi or pectoralis muscles. Schematic illustration of the acromion shape as described by Bigliani. Inclusion in an NLM database does not imply endorsement of, or agreement with,