- The joint is formed by articulation of the glenoid cavity of scapula & head of the humerus. Therefore, it is also known the glenohumeral articulation.
- The glenoid cavity is too small & narrow for head of humerus (4 times) . Hence, it is a weak joint, but this arrangement provides great motility.
- Motility at the cost of stability.
Factors maintaining stability –
- The coracoacromial arch or secondary socket for the head of the humerus
- The musculotendinous cuff of the shoulder
- The glenoidal labrum helps in deepening the glenoid fossa.
Also provided by the muscles attaching the humerus to the pectoral girdle, the long head of the biceps, the long head of the triceps, and atmospheric pressure.
- The capsular ligament:
- Is loose
- Permits free movements
- The coracohumeral ligament
- Transverse humeral ligament
- The glenoidal labrum
1.The subacromial (subdeltoid) bursa
2.The subscapularis bursa, communicates with the joint cavity.
3. The infraspinatus bursa, may communicate with the joint cavity.
Superiorly: Coracoacromial arch, subacromial bursa, supraspinatus and deltoid
Anteriorly: Subscapularis, coracobrachialis, short head of biceps and deltoid.
Within the joint: Tendon of long head, of biceps brachi
Posteriorly: Infraspinatus, teres minor and deltoid.
Inferiorly: Long head of the triceps brachii.
1.Anterior circumflex humeral vessels,
2.Posterior circumflex humeral vessels,
3.Suprascapular vessels, and
4.Subscapular vessels.
1.Axillary nerve,
2.Musculocutaneous nerve, and
3.Suprascapular nerve.
- IFLEX my PECS with my DELTOIDS –
Flexion – Pec Major & Deltoid
- EXcellent at Living Dreams –
Extension – Latissimus dorsi & Deltoid
- ADDing Laughter is ProMising –
Adduction – latissimus dorsi & Pec Major
- Superman’sABs DEaLT damage –
Abduction – Supraspinatus & Deltoid
- During the PM, I’m INTERNALly SUBconscious –
Internal Rotation – Pec Major & Subscapularis
- TIM went to the ER –
External Rotation – Teres Minor/Infraspinatus
-Soumya Khot and Dharmin Doshi