Shoulder Joint

• 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 –

1. The coracoacromial  arch  or  secondary  socket for  the  head of  the  humerus
2. The musculotendinous cuff  of  the  shoulder
3. 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.

1. The capsular  ligament:
   • Is loose
   • Permits free movements
2. The coracohumeral  ligament
3. Transverse humeral  ligament
4. 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.

1. IFLEX my PECS with my DELTOIDS –

Flexion – Pec Major & Deltoid

2. EXcellent at Living Dreams –

Extension – Latissimus dorsi & Deltoid

3. ADDing Laughter is ProMising –

Adduction – latissimus dorsi & Pec Major

4. Superman’sABs DEaLT damage –

Abduction – Supraspinatus & Deltoid

5. During the PM, I’m INTERNALly SUBconscious –

Internal Rotation – Pec Major & Subscapularis

6. TIM went to the ER –

External Rotation – Teres Minor/Infraspinatus

1. Dislocation
2. Optimum attitude
3. Shoulder tip pain
4. Frozen shoulder