Anatomy Dissection 10 - Posterior Shoulder and Rotator Cuff Muscles Flashcards
What are the 3 parts of the deltoid muscles?
Spinal Acromial Clavicular
Action of the spinal part of the deltoid muscle?
Extension at the shoulder
Action of the acromial part of the deltoid muscle?
Abduction at the shoulder (takes over from supraspinatus beyond 15 degrees)
Action of the clavicular part of the deltoid muscle?
Flexion at the shoulder
What are the 3 parts of the trapezius muscle?
Descending Middle Ascending
Action of the ascending trapezius?
depression of the scapula
Action of the middle trapezius?
Scapular retraction
Action of the descending trapezius?
Scapular elevation
what action occurs when the ascending and descending parts of the trapezius contracts?
Superior rotation of the glenoid fossa
Action of the elevator scapulae?
Elevation of scapulae Inferior rotation of gleaned fossa
Action of the rhomboid major?
Retraction of scapula Inferior rotation of glenoid fossa
Action of the rhomboid minor?
Retraction of scapula Inferior rotation of glenoid fossa
Name the 4 rotator cuff muscles?
Supraspinatus Infraspinatus Teres minor Subscapularis
Action of supraspinatus?
First 15 degrees of adduction at shoulder
Action of infraspinatus?
Stabilises head of humerus in glenoid Lateral rotation at shoulder
Action of teres minor?
stabilises head of humerus in glenoid Lateral rotation at shoulder
Action of subscapularis?
Stabilises head of humerus in glenoid Medial rotation at shoulder
Action of teres major?
Adduction Medial rotation at shoulder
When the upper limb is abducting, why is superior rotation of the glenoid fossa (by moving the scapula) required?
To prevent the greater tubercle of the humerus impinging on the accordion of the scapula
What does the distal tendons of all the rotator cuff muscles blend with and reinforce?
The fibrous capsule of the shoulder joint
What does the tendinous cuff of the shoulder joint help to do?
Stabilise the shallow ball and socket of the shoulder joitn
Attachments of the rotator cuff muscles?
Scapula proximally Tubercles of the head of the humerus (all greater except subscapularis = lesser)
Nerve supply of the rotator cuff muscle?
Branches of the brachial plexus
What causes “painful arc syndrome”?
Impingement of supraspinatus tendon between the humerus and the accordion process
What will patients with painful arc syndrome complain of?
Pain during 50 - 130 degrees of abduction
What will a patient with supraspinatus paralysis/ tendon tear do to initiate abduction?
Throw their upper limb to the side
What are the bones of the pectoral girdle?
Scapula Clavicle Manubrium of sternum
What part of the clavicle is frequently fractured?
Middle third
What is the most common rotator cuff injury?
Partial tear or complete rupture
Name this muscle

Deltoid
Name this muscle

Trapezius
Name this muscle

Levator scapulae
Name this muscle

Rhomboid major
Name this muscle

Rhomboid minor
Name this muscle

Teres Major
Name this muscle

Supraspinatus
Name this muscle

Infraspinatus
Name this muscle

Teres minor
Name this muscle

Subscapularis