Cystic lesions in the posterosuperior bare area of the humeral head should not be mistaken for degenerative sequels or vascular channels. The internal surface of the capsule is lined by a synovial membrane. 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). This resulted in a triangular-shaped section of tissue with the glenoid labrum and fibrous capsule attachment at the periphery. Provides insertion for stabilizing structures, as a fibrous crossroad, with the labrum and. 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. Located posteriorly between the posterior insertion of the joint capsule and synovial membrane and the adjacent articular cartilage, this bare area may be confused with a Hill-Sachs impaction injury ( Fig. A separate internal labral circumferential ridge 4 mm central to the glenoid rim marks the interface between the labrum and articular cartilage. 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. On fat-saturated T1-weighted MRA images obtained in (A) Coronal oblique and (B) Axial planes, the ligament appears as a thin hypointense band delimited by the distended axillary pouch or recess with a U-shaped appearance (arrow, A). In a type III BLC, a prominent triangular meniscoid labrum projects into the joint space and results in a deep recess that may be continuous with a sublabral foramen ( Fig. Baptist Health is known for advanced, superior care for patients with orthopedic conditions and the diagnosis, treatment and management of a glenoid labrum tear. Before On axial sections, the coracohumeral ligament is perpendicular to the superior glenohumeral ligament and anterior to the tendon of the long head of the biceps. 4. This is classically described as tear-drop, or oval shaped (Anetzberger and Putz 1996) and has a small surface area when compared to that of the humeral head. The latissimus dorsi originates from the spinous processes T6T12 and inserts into the medial intertubercular humeral groove. Some fibers of the teres minor interdigitate with those of the infraspinatus [2,3]. (A) Sagittal oblique PD-weighted MRA depicts the inferior glenohumeral ligament (thick arrows, A) with a high labral attachment (arrowhead, A). The sublabral foramen provides a communicating pathway between the glenohumeral joint and the subscapularis recess ( Fig. Its attachment extends slightly above to the adjacent glenoid labrum and blends with the glenohumeral capsule of the shoulder joint, contributing to its stability. 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). The infraspinatus inserts on approximately half of the superior facet and the entire middle facet of the greater tuberosity. Conventional radiographs of the shoulder. The acromioclavicular ligament is divided into superior and inferior part. A detached labrum can be repaired arthroscopically, with a small incision into which a scope and specialized tool is inserted. Glenohumeral joint (Articulatio glenohumeralis) -Yousun Koh. Blood supply and vascularity of the glenoid labrum: Its clinical Blood supply is also received from the underlying bony glenoid 5. In: Pope, T, Bloem, JL, Beltran, J, Morrison, W and Wilson, D (eds. Anatomic study of the superior glenoid labrum - PubMed It covers the intertubercular sulcus and the long head tendon of the biceps brachii muscle, preventing displacement of the tendon from the sulcus. Quantitative analysis of attachment of the labrum to the glenoid fossa Become a Gold Supporter and see no third-party ads. This review discusses the normal anatomy and anatomic variants of the glenoid labrum, articular cartilage, and glenohumeral ligaments. The first is on its anterior and inferior sides where the capsule inserts into the scapular neck, posterior to the glenoid labrum. This method provides multiplanar reconstructions, surface rendering of the osseous structures with rotation of the reconstructions and subtraction Figure Figure2.2. An additional bare area has been described between the supraspinatus insertion on the greater tuberosity and the adjacent articular cartilage. It forms the limits of the rotator interval together with the coracohumeral ligament and the anterosuperior aspect of the glenohumeral joint capsule [4,14]. Netter, F. (2019). Glenoid Labrum | Musculoskeletal Key Unable to process the form. Understanding the Glenoid Avulsion of the Glenohumeral - ScienceDirect Some of those muscle are represented in (Figure (Figure4)4) [5,6]. The sublabral foramen provides a communication between the glenohumeral joint and the subscapularis recess [7]. The glenohumeral joint is the articulation between the spherical head of the humerus and the concave glenoid fossa of the scapula. The labrum of the glenoid circumferentially surrounds the outer portion of the glenoid and is the point of insertion of all the glenohumeral ligamentous structures described above. The shoulder joint is considered a ball and socket joint. {"url":"/signup-modal-props.json?lang=us"}, Knipe H, Roberts D, Chmiel-Nowak M, et al. Gyftopoulos, S, Bencardino, J, Nevsky, G, et al. Most studies in the radiology literature provide only a generic description of the glenoid attachment of the anterior and posterior bands of the IGHL, stating they emerge from the labrum at the middle and lower thirds of the glenoid (6,10-15) or simply from the glenoid rim (16,17), and rarely do we find a more detailed description stating that . Pathology. Referring to a line connecting the anterior and posterior margins on axial images, three main shapes of the glenoid surface are described: (a) concave, (b) flat or (c) convex [3]. CT and MR arthrography of the normal and pathologic anterosuperior labrum and labral-bicipital complex, MR arthrography of the glenohumeral joint. [1], The labrum is frequently involved in shoulder pathology, by acute trauma (eg shoulder dislocation) or, more commonly, repeated microtrauma eg shoulder subluxation.[2]. Glenoid dysplasia is an important developmental abnormality. Failure to recognize and account for the bare area at imaging may lead to erroneous diagnosis or overestimation of partial thickness supraspinatus tendon tears. Classically, three ligaments are recognized: the superior glenohumeral ligament, the middle glenohumeral ligament and the inferior glenohumeral ligament (Figures (Figures1212 and and16).16). Compression of either of these structures can lead to subacromial impingement syndrome and/or subacromial bursitis [2]. A bare area has also been described in the mid third of the glenoid cavity; this is an oval area denuded of cartilage, probably developmental and should be differentiated from true cartilage injury (Figures (Figures66 and and7)7) [6,9]. The transverse humeral ligament is also intimately related to the biceps pulley (Figure 5, additional material). The different anatomical pitfalls mimicking pathologies are represented in Table Table44. The biceps pulley, also known as the biceps sling, is comprised of a combination of the coracohumeral, superior glenohumeral and transverse humeral ligaments. Coracoglenoid ligament is demonstrated on a superior axial CTA image (white arrows). Significant internal rotation should be avoided for conventional MR imaging of the shoulder because it results in medial displacement of the joint capsule and contraction of the subscapularis tendon, both of which may obscure the subjacent anteroinferior labrum. Evaluation of variations of the glenoid attachment of the inferior Direct MRA uses intra-articular injection of gadolinium based contrast with the same technical approach as for CTA. The inferior glenohumeral ligament actually consists of an anterior and posterior band as well as the axillary pouch that is reinforced by the fasciculus obliquus (or spiral glenohumeral ligament) on the glenoid side (Figure (Figure16).16). . The attachment of the labrum to the bony edge of the glenoid was observed under light microscopy at each position and classified into two . Together with the coracobrachialis muscle tendon it originates from the coracoid process and is well demonstrated on axial sections [2,3,4,5,12]. The site is secure. The labrum is described like a clock face with 12 o'clock being at the top ( superior ), 3 o'clock at the front ( anterior ), 6 o'clock at the bottom ( inferior) and 9 o'clock at the back ( posterior ). The long head of biceps tendon is secured within the bicipital groove by the transverse humeral ligament which passes between the greater and lesser tuberosities over the sheath of the tendon. The loose inferior capsule forms a fold when the arm is in the anatomical position. The superior, middle and inferior glenohumeral ligaments support the joint from the anteroinferior side. and transmitted securely. The glenohumeral ligaments are fibrous reinforcements of the glenohumeral capsule and represent the most important passive stabilizers of the shoulder joint (Figure (Figure12).12). Susan Standring. (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. Redundancy or type III is commonly observed for the posterior capsule. Under normal circumstances this bursa does not communicate with the joint space and is not seen on MRI unless it is distended by fluid. Kadi, R and Shahabpour, M. Normal MR imaging anatomy of the shoulder In: Shahabpour, M, Sutter, R and Kramer, J (eds.). (2015). government site. In addition, some patients experience discomfort and/or a sensation of instability, particularly with the ABER position, and may not be able to tolerate this portion of the examination. In type II, the capsule attaches on the glenoid neck within 1 cm of the labral base. The glenoid cavity or fossa forms a glenohumeral joint with the medial aspect of the humeral head (Figures 1 and 3, additional material). Axial fat-saturated T1-weighted MR arthrographic section at the level of the bicipital groove shows the biceps pulley (large arrow), formed by the fusion of the coracohumeral ligament, the superior glenohumeral ligament (thin arrow) and the transverse humeral ligament. are major limitations. There are several bursae around the shoulder, the most important being the subacromial, subdeltoid, subscapular, and subcoracoid bursae (Figure 13, additional material). The subscapular recess is located between the coracoid process superiorly and the superior margin of the subscapularis tendon. It is a strong fibrous triangular band that forms part of the roof of the glenohumeral joint. The supraspinatus and subscapularis tendons interdigitate as well and envelop the biceps tendon. Its posterior attachment to the supraspinatus tendon stabilizes the tendon of the long head of the biceps in the bicipital groove [2,4,6,14]. In type III, the attachment is more than 1 cm medial to the labrum (Figure 8, additional material). The tendon of the short head of the biceps muscle is anterior to the humeral head. On axial images a marked retroversion is found. (B) Sagittal oblique PD-weighted MRA shows the anterior band of the inferior glenohumeral ligament (white arrows, B) and the posterior band of this ligament (black arrows, B). Mochizuki, T, Sugaya, H, Uomizu, M, et al. The tubercle of Assaki is a ridge (focal zone of elevation) at the subchondral bone in the center of the glenoid cavity (Figure (Figure5).5). In this era of cost containment, completing the diagnostic workup in the clinic without expensive ancillary studies allows the patient's care to proceed in the most timely and economic fashion. 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. The absence of subchondral bone marrow signal abnormality and lack of intra-articular loose bodies are pertinent negative findings. Despite the continuity of labrum and most of the capsuloligamentous structures, distension of the joint may also result in the appearance of three distinct types of medial capsular attachment at the inferior attachment [14]. Being a synovial joint, both articular surfaces are covered with hyaline cartilage. Below the equatorial pole of the glenoid, the labrum becomes more rounded and smaller compared to superiorly where is more triangular in shape and larger. Bare area of the glenoid on MRI. The posterior capsule is torn at the humeral attachment (arrow). Typically considered to be triangular or rounded in cross section, a range of glenoid labral morphologies has been described. Top Contributors - Priyanka Chugh, Kim Jackson, Lucinda hampton, Naomi O'Reilly, 127.0.0.1 and Wanda van Niekerk, The glenoid labrum is a fibrocartilaginous complex that attaches as a rim to the articular cartilage of the glenoid fossa. Another subacromial pseudospur located at the deltoid tendon attachment to the undersurface of the acromion may mimic an enthesophyte when it is only visible on one single section (Figure (Figure11)11) [3,4]. A variable deep notch or a physiological flattening in the humeral neck is located posterior to the greater tubercle and best visualized on axial images; this pitfall should not be mistaken for a Hill-Sachs impaction which is seen at or above the level of the coracoid process (Figure (Figure4)4) [4,5]. The proximal humerus consists of the humeral head, the greater and lesser tuberosities, the humeral neck, and the bicipital groove (Figures 1 and 2, additional material). A true tear typically propagates a greater distance superiorly into the bicipital anchor or inferiorly into the inferior glenohumeral ligament attachment site [7]. Subacromial pseudospur. Appropriate MR imaging protocols and sequences and applied MR anatomy of the shoulder (including normal variants) are proposed to help assist management and treatment of common shoulder pathologies encountered (such as rotator cuff tears, impingement syndromes, and instability as well as less frequent causes of shoulder pain). Physiopedia articles are best used to find the original sources of information (see the references list at the bottom of the article). This bursa is bounded superiorly by the deltoid, acromion, and coracoacromial ligament and inferiorly by the rotator cuff, in particular the supraspinatus. Normal humeral head versus Hill-Sachs lesion. It is a flat, gliding joint that gives the shoulder additional flexibility which is not possible with the glenohumeral joint alone. Previous reports have shown the labrum to be predominantly composed of fibrous tissue with some fibrocartilaginous components at the chondrolabral junction. The interdigitation is more prominent when the shoulder is internally rotated and should not be confused with tendinopathy on MR imaging [7]. Edinburgh: Churchill Livingstone. The glenoid labrum can be described in two ways 4: Please Note: You can also scroll through stacks with your mouse wheel or the keyboard arrow keys. 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. The sublabral foramen should not be confused with an anterosuperior labral tear in patients with clinical symptoms. National Library of Medicine On the humerus, the capsule attaches to its anatomical neck. Distal to the spinoglenoid notch, the suprascapular nerve divides in two or more muscular branches that supply the infraspinatus muscle (Figure 14, additional material). Reviewer: The labral outline is ovoid in configuration, conforming to the underlying glenoid rim, and is most firmly attached to the glenoid posteriorly and inferiorly. According to his theory, a full-thickness tear will correspond to a rupture of both bundles, a partial-thickness tear to a rupture of one of the two strings. not be relevant to the changes that were made. Basic biomechanics (7th ed.). The glenoid cavity is retroverted, approximately 5 to 7 [8]. In that case the capsular recess can be prominent anteriorly and beneath the subscapularis tendon [3,4]. Glenoid Labrum Tear Treatment at Baptist Health: Our Approach. They can extend into the tendon, involve the glenohumeral ligaments or extend into other quadrants of the labrum. The long head of biceps tendon is covered by a synovial sheath that communicates with the joint capsule. The teres minor muscle arises from the dorsolateral scapula; it inserts into the lowest or most posterior part of the facets of the greater tuberosity. The patient is placed in supine position with the arm in mild external rotation. Being a synovial joint, both articular surfaces are covered with hyaline cartilage. In type B attachments, intermediate signal intensity may be noted at the chondrolabral junction corresponding to the transitional zone of fibrocartilage, which should not be misinterpreted as a labral tear. Several reports have detailed the importance of proper shoulder positioning to optimize evaluation of its complex anatomy and specifically to aid in detection of subtle abnormalities of the glenoid labrum and GHLs. Philadelphia, PA: Wolters Kluwer Health/Lippincott, Williams & Wilkins. Constricted joint fluid access to the subscapularis recess through the sublabral foramen should not be misconstrued as a type II SLAP tear with associated paralabral cyst. The .gov means its official. Glenoid Labrum Tear - Symptoms, Causes, Treatment and Rehabilitation The cause (which is usually shoulder instability), however, needs to be assessed and treated. Shoulder Injury: MRI Pitfalls In: Peh, WC (ed.). MR imaging of the shoulder with the arm in alternate positions has been advocated to better assess the integrity of specific labroligamentous structures. Coracohumeral ligament (lateral view) The last two ligaments to be discussed are the coracohumeral and transverse humeral ligaments. The anterior band arises from the inferior glenoid rim at the two oclock to four oclock positions. This ligament originates from the coracoid process and terminates on the humeral head where it incorporates into the capsule before attaching on the greater and lesser tuberosities, creating a tunnel for the biceps tendon. The long head of biceps tendon is secured within the bicipital groove by the transverse humeral ligament which passes between the greater and lesser tuberosities over the sheath of the tendon. (2008) ISBN: 9780443066849 -. Again, location is a key factor because the normal foramen is identified along the anterosuperior quadrant between the 1-oclock to 3-oclock position. Journal of Orthopaedic Surgery. The presence of high origin of the anterior band of the IGHL was recently reported as a potential imitator of sublabral foramen. A posterior labral tear (reverse Bankart) is also present (arrowhead), and a bone bruise is seen within the . According to Bigliani et al., the acromion is classified into three types: I (flat), II (curved), and III (hooked) (Figure (Figure8).8). The capsule remains lax to allow for mobility of the upper limb. At the time the article was created Henry Knipe had no recorded disclosures. Palastanga, N., & Soames, R. (2012). 2000;20 Spec No(suppl_1):S67-81. Smooth margins of the foramen, no significant displacement (<12 mm) of the detached labrum, and lack of associated traumatic injuries in the adjacent capsuloligamentous structures are additional helpful parameters to distinguish this variant from a labral tear. Individuals with a larger cable are termed cable dominant. Coracohumeral ligament. Springer. It stabilizes the anterior capsule, limiting externalrotation, particularly when the arm is in an abducted position (45o 60o abduction). The articular cartilage of the humeral head is thicker centrally and thinner peripherally contrary to the glenoid articular cartilage which is relatively thinner centrally and thicker peripherally [7]. The role of this bursa is to decrease frictional forces on the supraspinatus tendon and between the deltoid and the rotator cuff. Federal government websites often end in .gov or .mil. 1173185. This conjoined structure is called the biceps labral complex or bicipital anchor, where the fibrous tissue of the labrum blends with the biceps tendon (Figure (Figure17).17). It courses between the anterosuperior glenoid rim and the humeral head, just above the greater tuberosity (Figure (Figure18)18) [3]. Imaging of the shoulder in flexion, adduction, and internal rotation (FADIR) has been advocated to better evaluate the posterior capsulolabral complex. Read more. The coracoclavicular ligament complex, which connects the distal end of the clavicle to the coracoid process, controls vertical stability of the acromioclavicular joint. Medial to the triceps muscle is the triangular space, bordered superiorly by the teres minor muscle and inferiorly by the teres major muscle. That is usually the journal article where the information was first stated. The fact that these folds are in the nondependent position of the recess will help distinguish them from true loose bodies [7]. Schematic illustration of the acromion shape as described by Bigliani. To move and support the shoulder, different structures must work in synergy like muscles, tendons, ligaments, and cartilaginous structures. This ligament runs horizontally, almost parallel to the long head of the biceps tendon, straight in the direction of the coracoid process. It links the trunk to the upper limb and plays an important biomechanical role in daily activities. Joints and ligaments of the upper limb: Anatomy | Kenhub Sublabral foramen (sublabral hole). The glenoid labrum is a fibrocartilaginous complex that attaches as a rim to the articular cartilage of the glenoid fossa. Magee, D. J. Instead, they are typically pseudocysts that communicate with the joint space and represent a normal variant (Figure (Figure3)3) [4,6]. At any point in time, 25% of adults will deal with shoulder pain due to injury or overuse. On arthroscopic images, the rotator cable appears as a fibrous transverse band surrounding the rotator crescent. The supernumerary head is thought to be present in 9.122.9% of the population, more commonly seen in Asians. Additional views with different projections (as an axial view, also called axillary superoinferior view) can be used to explore the shoulder for detection of specific pathologies as described in Table Table11 and Figure Figure11 [1].
Millimolar To Moles Per Liter,
Charles Drury Obituary,
Baron Herzog White Wine,
Articles G
