Upper Limb 2 Flashcards
What is muscle A?
Supraspinatus
What is muscle B?
Subscapularis
What is muscle D?
Infraspinatus
What is muscle C?
Teres minor
What is the proximal and distal attachment of the subscapularis?
Proximal - medial 2/3 costal aspect of scapula
Distal - lesser tubercle of humerus
What does the subscapularis do in movement of shoulder joint?
Medially rotates and adducts joint
What is the proximal and distal attachment of the supraspinatus muscle?
Proximal - supraspinous fossa of scapula
Distal - greater tuberosity of humerus
What movement of the shoulder does the supraspinatus muscle do?
Initiates and assists in abduction of shoulder joint
What is the proximal and distal attachments of the infraspinatus muscle?
Proximal - infraspinatous fossa of scapula
Distal - middle facet of greater tubercle of humerus
What is the movement of shoulder that infraspinatus does?
Laterally rotates shoulder joint
What is the proximal and distal attachment of the teres minor?
Proximal - middle part of lateral border of scapula
Distal - greater tuberosity of humerus
What is the movement of shoulder which teres minor does?
Laterally rotates shoulder joint
What is the main function of the rotator cuff muscles?
Keep shoulder and upper arm stable when moving and in use
What is the cause of rotator cuff injuries?
Repetitive overhead motions
Increased stress on ligaments and muscles weakens them - so more likely to tear
Where does the deltoid muscle arise?
Lateral spine of scapula passing across the acromion to lateral third of clavicle
What is the distal attachment of the deltoid?
Deltoid tuberosity of humerus
What is the function of the anterior fibres of the deltoid?
Flexes and medially rotates at the shoulder joint
What is the function of the middle fibres of the deltoid?
Abducts the arm of the shoulder joint
What in the function of the posterior fibres of the deltoid muscle?
Extends and laterally rotates shoulder joint
What is the nerve supply to the deltoid?
Axillary nerve - C5 and C6
What common injury causes axillary nerve to be trapped and damaged?
Fracture of humerus
What is the origin of the pectoralis major?
Medial third of clavicle, sternum, costal cartilage of first 6 ribs and rectus sheath
What is the distal attachment of the pectoralis major?
Lateral lip of the bicipital groove of humerus
What is the action of the pectoralis major?
Adduct the shoulder and medially rotate the humerus at the glenohumeral joint
What is the function of the pectoralis minor?
Stabilises the scapula during limb movements by keeping it pulled against the thoracic cage
Where does the serratus anterior arise and insert?
Arises from interdigitations from ribs and inserts into scapula
What is the role of the serratus anterior?
Protection of the scapula
What nerve is affected when a patient has winged scapula?
Long thoracic nerve (C5,6 and 7) which supplies the serratus anterior
What is the role of the superior fibres of the trapezius?
Elevates the scapula
What is the role of the middle fibres of the trapezius?
Retracts the scapula
What is the role of the inferior fibres of the trapezius?
Depresses the scapula
What is the innervation of the trapezius?
Spinal accessory nerve
What muscles are involved in flexion of the shoulder?
Pectoralis major, anterior fibres of deltoid and coracobrachialis
What muscles are involved in the extension of the shoulder?
Posterior fibres of deltoid, latissimus dorsi and teres major
What muscles are involved in adduction of the shoulder?
Pectoralis major, latissimus dorsi, teres major and coracobrachialis
What muscles are involved in the abduction of the shoulder from 0 to 90 degrees?
Supraspinatus and deltoid