بسم الله الرحمن الرحيم Shoulder Joint (Gleno-Humeral) & Axilla Dr. Sama ul Haque

Objectives  Understand the formation of the shoulder joint and its type.  Explain the structures related to the shoulder joint.  Name the movements taking place on shoulder joint.  Define shoulder joint dislocation and subluxation.  Define axilla.  Know the boundaries and contents of the axilla.

Shoulder joint  Articulation  Type  Capsule  Ligaments  Movements

Bones forming Shoulder joint

Capsule and ligaments of the Shoulder Joint

Movements at the Shoulder Joint  Adduction  Abduction  Flexion  Extension  Circumduction  Rotation

Adduction – pectoralis major, lattisimus dorsi. Abduction– deltoid, supraspinatus. Flexion – pectoralis major, deltoid (anterior), – coracobrachialis, biceps. Extension – latissimus dorsi, deltoid (posterior); – pectoralis major from flexed position - triceps (long head). Medial Rotation – subscapularis, pectoralis major, deltoid (anterior), – latissimus dorsi, teres major; Lateral Rotation – infraspinatus, teres minor, deltoid (posterior). Key Muscles that act across the Shoulder Joint.

Definitions  Dislocation: The joint surfaces are completely displaced and are no longer in contact.  Subluxation: A lesser degree of displacement, such that the articular surfaces are still partly apposed.  Fracture: Fracture is a break in the structural continuity of bone.

A.Subluxation B.Partial dislocation C.Complete dislocation

Dislocation of shoulder joint

Causes of shoulder dislocation Shoulder joint is commonly dislocated due to it’s freedom of movement and instability. Common causes are:  A fall on the hand.  Excessive extension and lateral rotation of the hummers.

Axilla (Armpit)

The axilla is the region between the pectoral muscles, the scapula, the arm and the thoracic wall. It is a region through which vessels and nerves pass from the root of the neck into the upper limb.

Axilla is a space  4 Sided pyramid  Apex connected to the neck  Base Arm pit  Anterior wall  Posterior wall  Medial wall  Lateral wall

Section of Axilla

Boundaries of the Axilla Apex: Clavicle anteriorly, the upper border of the scapula posteriorly and the first rib medially. Base: Skin and fascia of the arm pit

Boundaries of the Axilla Anterior wall: Pectoralis major muscle, Pectoralis minor muscle, and the clavipectoral fascia Posterior wall: Posterior axillary fold (teres major and Latissimus dorsi) and the subscapularis. Medial wall: Upper portion of the thoracic wall and the serratus anterior muscle. Lateral wall: Intertubercular sulcus of the Humerus.

Contents of the Axilla 1.Axillary sheath 2.Brachial plexus :are the nerves which supply the upper limb 3.Axillary vessels and their branches 4.Lymph nodes 5.Lymphatic vessels 6.fat

The Axilla.

Thank you.