The labrum is triangular in section; the base is fixed to the circumference of the cavity, while the free edge is thin and sharp.
It is continuous above with the tendon of the long head of the biceps brachii, which gives off two fascicles to blend with the fibrous tissue of the labrum.
Glenoid labrum. Schematic drawing of the transverse section. Morphologic variants of the glenoid labrum with relative distribution in percentage for the anterior labrum. a: 50%. Triangular with line of increased signal intensity along the hyalin articular cartilage. b: 20%. Rounded. c: 7%. Comma-shaped flattened. d: 3%. Absent. e: 15%. Cleaved. f: 8%. Notched. g: Central increase in signal intensity. h: Linear increase in signal intensity. The posterior labrum generally exhibits a triangular or rounded form.
Clinical significance
Injury
Tearing of the labrum can occur from either acute trauma or repetitive shoulder motion such as in the sports of swimming, baseball and football. Acute trauma may be from dislocation of the shoulder, direct blows to the shoulder, and other accidents of the sort. Tears are classified as either superior or inferior in regards to where the tear is in the glenoid cavity. A SLAP lesion (superior labrum, anterior to posterior) is a tear where the glenoid labrum meets the tendon of the long head of the biceps muscle. Symptoms include increased pain with overhead activity, popping or grinding, loss of strength, and trouble localizing a specific point of pain.[3] Because a SLAP lesion involves the biceps, pain and weakness may also be felt when performing elbowflexion with resistance.
Diagnosis
Clinicians can use any combination of the following manual tests to assist in determining if a labral tear has occurred; Jobe Relocation, O'Brien, Anterior Apprehension, Bicipital Groove Tenderness, Crank, Speed, and Yergason tests. As a general rule, abnormal pain experienced during any of these tests will indicate a positive result, or a tear of the glenoid labrum. All of the tests take advantage of the fact that the labrum meets the tendon of the long head of the biceps muscle, and thus will normally produce pain in the region if a tear is present. Additionally, clinicians may order an MRI (Magnetic Resonance Imaging) or CT (Computed Tomography) scan to be conducted utilizing contrast injections to highlight where tears may be present. However, due to inherent variability between humans, manual tests, when possible, are more accurate in determining the presence of a labral tear.[4]
Treatment
Detachment of the glenoid labrum often requires surgery to reattach it to the glenoid fossa.[5] Arthroscopic surgical techniques can also be used for more minor detachments.[5]
This article incorporates text in the public domain from page 319 of the 20th edition ofGray's Anatomy(1918)
^Carter, Kevin.; Mudigonda, Sanjay. (1 January 2009), Weissman, Barbara N. (ed.), "Chapter 5 - Arthrography and Injection Procedures", Imaging of Arthritis and Metabolic Bone Disease, Philadelphia: W.B. Saunders, pp. 60–80, doi:10.1016/b978-0-323-04177-5.00005-7, ISBN978-0-323-04177-5, retrieved 25 October 2020
^Lodha, Sameer; Mazloom, Sean; Resler, Amy G.; Frank, Rachel M.; Ghodadra, Neil S.; Romeo, Anthony A.; Kim, Jonathan Yong; Jadgchew, R. Jason; Provencher, Matthew T. (1 January 2018), Giangarra, Charles E.; Manske, Robert C. (eds.), "24 - Shoulder Instability Treatment and Rehabilitation", Clinical Orthopaedic Rehabilitation: a Team Approach (Fourth Edition), Philadelphia: Content Repository Only!, pp. 130–157.e1, ISBN978-0-323-39370-6, retrieved 25 October 2020
^Romeyn, Richard; Manske, Robert C. (1 January 2018), Giangarra, Charles E.; Manske, Robert C. (eds.), "21 - Importance of the History in the Diagnosis of Shoulder Pathology", Clinical Orthopaedic Rehabilitation: a Team Approach (Fourth Edition), Philadelphia: Content Repository Only!, pp. 100–109.e1, ISBN978-0-323-39370-6, retrieved 25 October 2020
^Guanche, C (2003). "Clinical Testing for Tears of the Glenoid Labrum" (PDF). Arthroscopy. 19 (5): 517–523. doi:10.1053/jars.2003.50104. PMID 12724682. Retrieved 28 November 2016.
^ abWatling, J. P.; Brabston, E. W.; Padaki, A. S.; Ahmad, C. S. (1 January 2015), Greiwe, R. Michael (ed.), "1 - Anterior instability: Shoulder dislocations, instability, and the labrum", Shoulder and Elbow Trauma and its Complications, Woodhead Publishing Series in Biomaterials, Woodhead Publishing, pp. 3–22, doi:10.1016/b978-1-78242-449-9.00001-7, ISBN978-1-78242-449-9, retrieved 25 October 2020
External links
Wikimedia Commons has media related to Glenoid labrum.
glenoid, labrum, glenoid, labrum, glenoid, ligament, fibrocartilaginous, structure, fibrocartilage, previously, thought, attached, around, margin, glenoid, cavity, shoulder, blade, shoulder, joint, considered, ball, socket, joint, however, bony, terms, socket,. The glenoid labrum glenoid ligament is a fibrocartilaginous structure not a fibrocartilage as previously thought rim attached around the margin of the glenoid cavity in the shoulder blade The shoulder joint is considered a ball and socket joint However in bony terms the socket the glenoid fossa of the scapula is quite shallow and small covering at most only a third of the ball the head of the humerus The socket is deepened by the glenoid labrum stabilizing the shoulder joint 1 2 Glenoidal labrumLateral view of the shoulder showing the glenoid labrum marked glenoid lig DetailsIdentifiersLatinlabrum glenoidaleTA98A03 5 08 002TA21765FMA23290Anatomical terminology edit on Wikidata The labrum is triangular in section the base is fixed to the circumference of the cavity while the free edge is thin and sharp It is continuous above with the tendon of the long head of the biceps brachii which gives off two fascicles to blend with the fibrous tissue of the labrum Contents 1 Structure 2 Clinical significance 2 1 Injury 2 2 Diagnosis 2 3 Treatment 3 See also 4 References 5 External linksStructure Edit Glenoid labrum Schematic drawing of the transverse section Morphologic variants of the glenoid labrum with relative distribution in percentage for the anterior labrum a 50 Triangular with line of increased signal intensity along the hyalin articular cartilage b 20 Rounded c 7 Comma shaped flattened d 3 Absent e 15 Cleaved f 8 Notched g Central increase in signal intensity h Linear increase in signal intensity The posterior labrum generally exhibits a triangular or rounded form Clinical significance EditInjury Edit Tearing of the labrum can occur from either acute trauma or repetitive shoulder motion such as in the sports of swimming baseball and football Acute trauma may be from dislocation of the shoulder direct blows to the shoulder and other accidents of the sort Tears are classified as either superior or inferior in regards to where the tear is in the glenoid cavity A SLAP lesion superior labrum anterior to posterior is a tear where the glenoid labrum meets the tendon of the long head of the biceps muscle Symptoms include increased pain with overhead activity popping or grinding loss of strength and trouble localizing a specific point of pain 3 Because a SLAP lesion involves the biceps pain and weakness may also be felt when performing elbow flexion with resistance Diagnosis Edit Clinicians can use any combination of the following manual tests to assist in determining if a labral tear has occurred Jobe Relocation O Brien Anterior Apprehension Bicipital Groove Tenderness Crank Speed and Yergason tests As a general rule abnormal pain experienced during any of these tests will indicate a positive result or a tear of the glenoid labrum All of the tests take advantage of the fact that the labrum meets the tendon of the long head of the biceps muscle and thus will normally produce pain in the region if a tear is present Additionally clinicians may order an MRI Magnetic Resonance Imaging or CT Computed Tomography scan to be conducted utilizing contrast injections to highlight where tears may be present However due to inherent variability between humans manual tests when possible are more accurate in determining the presence of a labral tear 4 Treatment Edit Detachment of the glenoid labrum often requires surgery to reattach it to the glenoid fossa 5 Arthroscopic surgical techniques can also be used for more minor detachments 5 See also EditThis article uses anatomical terminology Bankart lesion Hill Sachs lesionReferences Edit This article incorporates text in the public domain from page 319 of the 20th edition of Gray s Anatomy 1918 Carter Kevin Mudigonda Sanjay 1 January 2009 Weissman Barbara N ed Chapter 5 Arthrography and Injection Procedures Imaging of Arthritis and Metabolic Bone Disease Philadelphia W B Saunders pp 60 80 doi 10 1016 b978 0 323 04177 5 00005 7 ISBN 978 0 323 04177 5 retrieved 25 October 2020 Lodha Sameer Mazloom Sean Resler Amy G Frank Rachel M Ghodadra Neil S Romeo Anthony A Kim Jonathan Yong Jadgchew R Jason Provencher Matthew T 1 January 2018 Giangarra Charles E Manske Robert C eds 24 Shoulder Instability Treatment and Rehabilitation Clinical Orthopaedic Rehabilitation a Team Approach Fourth Edition Philadelphia Content Repository Only pp 130 157 e1 ISBN 978 0 323 39370 6 retrieved 25 October 2020 Romeyn Richard Manske Robert C 1 January 2018 Giangarra Charles E Manske Robert C eds 21 Importance of the History in the Diagnosis of Shoulder Pathology Clinical Orthopaedic Rehabilitation a Team Approach Fourth Edition Philadelphia Content Repository Only pp 100 109 e1 ISBN 978 0 323 39370 6 retrieved 25 October 2020 Guanche C 2003 Clinical Testing for Tears of the Glenoid Labrum PDF Arthroscopy 19 5 517 523 doi 10 1053 jars 2003 50104 PMID 12724682 Retrieved 28 November 2016 a b Watling J P Brabston E W Padaki A S Ahmad C S 1 January 2015 Greiwe R Michael ed 1 Anterior instability Shoulder dislocations instability and the labrum Shoulder and Elbow Trauma and its Complications Woodhead Publishing Series in Biomaterials Woodhead Publishing pp 3 22 doi 10 1016 b978 1 78242 449 9 00001 7 ISBN 978 1 78242 449 9 retrieved 25 October 2020External links Edit Wikimedia Commons has media related to Glenoid labrum upper 20extremity arthrogramaxial2 at the Dartmouth Medical School s Department of Anatomy http orthoinfo aaos org topic cfm topic a00426 https web archive org web 20121119012737 http www orthospecmd com SLAPlesion html http www carlosguanchemd com wp content uploads 2012 08 Clinical Testing for Tears of the Glenoid Labrum pdf Portal Anatomy Retrieved from https en wikipedia org w index php title Glenoid labrum amp oldid 1024570861, wikipedia, wiki, book, books, library,
