Shoulder Viva

Question 0

Name the bones involved in the joints of the shoulder and shoulder girdle and classify these joints

Answer 0

Sternoclavicular joint: medial end of the clavicle, manubrium of sternum and first costal cartilage. Convex inferomedial line. Synovial saddle joint.
Acromioclavicular joint: lateral end of the clavicle, medial edge of the acromion. Synovial plane joint.
Glenohumeral joint: glenoid fossa of scapula and head of humerus. Arc from coracoid process under acromion process. Synovial ball and socket joint.

Question 1

Bony points of the shoulder and shoulder girdle

Answer 1

Inferior angle and medial border of scapula.
Spine of scapula.
Acromial angle and acromion process.
Coracoid process.
Intertubercular sulcus of humerus.
Lesser tubercle, greater tubercle, three facets.
Clavicle.

Question 2

Give the attachments of some ligaments at the shoulder and shoulder girdle

Answer 2

Acromioclavicular ligament: a square ligament covering the superior part of the joint, blending with the capsule.
Anterior sternoclavicular ligament: anteromedial aspect of the clavicle to the anterosuperior aspect of the manubrium and the first costal cartilage.
Interclavicular ligament: joins the medial ends of the two clavicles together.

Question 3

Give the attachments and actions of Deltoid

Answer 3

Proximal:
Anterior fibres: lateral half of the anterior and superior aspect of the clavicle.
Middle fibres: tendinous slips from lateral margin of the acromion process.
Posterior fibres: spine of scapula.
Distal: fibres converge to attach to the deltoid tuberosity of the lateral aspect of the humerus.
Actions:
Anterior fibres: flexion and medial rotation of shoulder.
Middle fibres: abduction of the shoulder (first 20’ initiated by supraspinatous)
Posterior fibres: extension and lateral rotation of the shoulder.

Question 4

Give the attachments and actions of Biceps Brachii

Answer 4

Proximal: long head- tendon runs through the intertubercular sulcus to attach to the supraglenoid tubercle. Short head- coracoid process, lateral to the attachment of Coracobrachialis.
Distal: tendon attaches to radial tuberosity, medial border gives off an aponeurosis which attaches to the posterior border of the ulna and deep fascia of the forearm.
Actions: flexion of the elbow and supination at 90’ flexion. Also weak shoulder flexor.
Passively insufficient when both elbow and shoulder are extended.

Question 5

Give the nerve supply of Deltoid and Biceps Brachii

Answer 5

Deltoid: Axillary Nerve C5, C6.

Biceps Brachii: Musculocutaneous Nerve C5, C6.

Question 6

Give the attachments and actions of Trapezius

Answer 6

Proximal: medial one third of superior nuchal line and external occipital protuberance of the occipital bone of the skull. Ligamentum nuchae. Spinous processes of C7-T12.
Distal:
Upper fibres: posterior border of lateral one third of clavicle.
Middle fibres: medial border of acromion and upper border of the crest of the spine of the scapula.
Lower fibres: tubercle on medial end of spine of scapula.
Actions over the shoulder girdle:
Upper fibres: elevation (can also produce ipsilateral side flexion of the neck and neck extension).
Middle fibres: retract the scapula.
Lower fibres: depression of the scapula.
Upper and lower fibres together: laterally rotate the scapula.

Question 7

Nerve supply of Trapezius

Answer 7

Motor supply: Spinal part of Accessory Nerve.

Sensory fibres from ventral rami of C3 and C4 of the cervical plexus.

Question 8

Describe the axilla

Answer 8

Apex:
Anterior border: clavicle.
Posterior border: upper border of the scapula.
Medial border: outer border of first rib.
Base:
Anterior border: anterior axillary fold (Pectoralis Major).
Posterior border: posterior axillary fold (Teres Major and tendon of Latissimus Dorsi).
Medial border: chest wall.
Walls:
Anterior wall: Pectoralis Major, Pectoralis Minor, Subclavius.
Posterior wall: Subscapularis, Latissimus Dorsi, Teres Major.
Medial wall: upper 4 or 5 ribs and intercostal spaces covered by Serratus Anterior.
Lateral wall: the humerus, Coracobrachialis, Biceps Brachii.
Contents:
Axillary artery and vein.
Nerves of brachial plexus.
Lymph nodes.

Question 9

Describe the scapulohumeral rhythm

Answer 9

When the arm is elevated either through abduction or flexion, the first 30’ occurs at the glenohumeral joint. The remainder of the movement occurs in a 2:1 ratio of glenohumeral to scapular movement.