Shoulder Joint (Glenohumeral): Rotator Cuff, Capsule & Ligaments | Anatomy Explained скачать в хорошем качестве

Shoulder Joint (Glenohumeral): Rotator Cuff, Capsule & Ligaments | Anatomy Explained

Content: 00:00 Introduction & Content 00:51 Shoulder Joint Components 05:25 Rotator Cuff Muscles 08:18 Bursae of the Shoulder 10:14 Outro & Next Topic ------------------ 🫀Help me make more free educational content:    / @taimtalksmed   📲Other Links: Website: https://taimtalksmed.com/ Instagram:   / taimtalksmed   Discord:   / discord   ------------------- This video is about the shoulder joint. In this video, we break down all the anatomical structures that make and support the shoulder joint (bones, ligaments, bursae, rotator cuff muscles). Structures involved in the shoulder joint: Bones and Articular Surfaces: • Scapula – Flat, triangular bone forming the posterior base of the shoulder joint. • Humerus – Long bone of the upper arm; the head articulates with the glenoid cavity. • Clavicle – Acts as a strut between the sternum and scapula. • Glenoid cavity (Cavitas glenoidalis) – Shallow socket on the scapula that receives the head of the humerus. • Head of humerus (Caput humeri) – Ball-shaped proximal end of the humerus that articulates with the scapula. • Anatomical neck of humerus – Narrowing just below the humeral head; attachment site for the joint capsule. • Intertubercular groove (Sulcus intertubercularis) – Groove between the tubercles of the humerus for the biceps tendon. Labrum and Capsule: • Glenoid labrum (Labrum glenoidale) – Fibrocartilaginous rim that deepens the glenoid cavity for stability. • Articular capsule (Capsula articularis) – Encloses the joint and blends with periosteum. • Synovial membrane – Inner lining of the joint capsule that produces synovial fluid. • Fibrous capsule – Outer layer providing mechanical support. • Axillary recess – Inferior fold of the capsule allowing arm abduction. Glenohumeral Ligaments: • Superior glenohumeral ligament – Stabilizes the joint when the arm is at rest. • Middle glenohumeral ligament – Stabilizes during mid-range abduction and rotation. • Inferior glenohumeral ligament – Strongest, prevents anterior dislocation in abducted/externally rotated arm (ABER position). • Coracohumeral ligament – Supports the superior capsule, limits external rotation. • Transverse humeral ligament – Covers the bicipital groove and holds the biceps tendon in place. Coracoacromial Arch & Ligaments: • Coracoacromial ligament – Connects the coracoid process to the acromion, forming a superior arch. • Coracoacromial arch – Prevents upward displacement of the humeral head. • Acromioclavicular joint – Between clavicle and acromion; involved in arm elevation. • Coracoclavicular ligament – Anchors clavicle to scapula, indirect shoulder stabilizer. Rotator Cuff Muscles (Mnemonics SITS): • Supraspinatus – Initiates abduction; commonly involved in impingement. • Infraspinatus – External rotator, active in deceleration during throwing. • Teres minor – Assists with external rotation and stabilization. • Subscapularis – Primary internal rotator and anterior stabilizer. Other Muscles Mentioned: • Deltoid – Abducts the arm after supraspinatus initiates the movement. • Teres major – Assists with internal rotation and adduction. • Biceps brachii (long head) – Originates from supraglenoid tubercle; involved in shoulder stabilization. Tendons and Sheaths: • Long head of biceps tendon – Intracapsular, extrasynovial tendon that stabilizes the joint and is prone to tendinitis. • Intertubercular tendon sheath – Encloses the long head of biceps in the bicipital groove. Bursae of the Shoulder: • Subacromial bursa – Between acromion and supraspinatus tendon; inflamed in impingement. • Subdeltoid bursa – Cushions the deltoid muscle over the joint capsule. • Subtendinous bursa of teres major – Reduces friction under teres major. • Coracobrachial bursa – Lies beneath coracobrachialis muscle. • Coracoclavicular bursa – Found between coracoid process and clavicle. • Subcutaneous acromial bursa – Superficial, aids with overhead arm motion. Clinical Conditions Discussed: • Shoulder dislocation (especially anterior in ABER position) • SLAP tear (Superior Labrum Anterior Posterior lesion) • Rotator cuff tear (especially supraspinatus tendon) • Subacromial impingement syndrome • Frozen shoulder (Adhesive capsulitis) • Biceps tendinitis and instability • Shoulder pain during overhead activity • Weakness and limited range of motion due to cuff dysfunction Sources: • Kozlowski, T. (2017). Memorix Anatomy, 2nd ed. • Standring, S. (2020). Gray’s Anatomy, 42nd edition • Tubbs RS, Shoja MM, Loukas M. (2016). Bergman’s Encyclopedia of Human Anatomic Variation • White TD, Folkens PA. (2005). The Human Bone Manual Programs used: Complete Anatomy, Biorender, PowerPoint