Week 1 - Superficial Back, Shoulder, Scapular Region Flashcards
What is the nerve supply of the trapezious muscle?
Accessory nerve (CN XI)
What muscles connect the upper limb to the vertebral column?
Trapezius, latissimus dorsi, rhomboid minor & rhomboid major
What is the nerve supply of the latissimus dorsi muscle?
Thoracodorsal nerve
What is the nerve supply of the rhomboid muscles?
Dorsal scapular nerve
What does the trapezius do and what happens if it’s nerve supply is injured?
The trapezius elevates, retracts & depresses the scapula. If the accessory nerve (CN XI) is damaged, it could cause a ‘droopy’ shoulder. The cranial nerves, C3 & C4 also supply the trapezius.
What is the function of the latissimus dorsi?
It functions to extend, adduct and medially rotate the humerus at the shoulder joint.
What muscle of the back connects the upper limb with the thoracic wall? What is its nerve supply?
Serratus anterior, long thoracic nerve - Injury to this nerve produces the ‘winged scapula’
What functions are associated with the deltoid?
It accounts for the roundness of the shoulder. Its anterior fibers flex and medially rotate the humerus. Its middle fibers - chief abductor of the humerus. Its posterior fibers extend laterally and rotate the humerus.
What nerve supplies the deltoid and when would this nerve likely be injured?
Axillary nerve. The deltoid will atrophy if the axillary nerve (C5 and C6) is severely damaged. It’s usually injured during a fracture to the humerus or the improper use of crutches. If the muscle atrophies, it will result in a loss of sensation and a flattened appearance.
How do you clinically test the function of the deltoid?
The arm is abducted starting from about 15 degrees, against resistance. If acting normally, the deltoid can easily be seen and palpated. The influence of gravity is avoided when the person is supine.
What muscles form the posterior axillary fold? What is their nerve supply?
(one side of the armpit) latissimus dorsi and teres major. The Latissimus dorsi is supplied by the thoracodorsal nerve and the nerve supply of the teres major is the lower subscapular nerve
What muscles connect the scapula with the humerus?
Teres major (mostly) & teres minor - The teres major is innervated by the lower subscapular nerve while the teres minor is innvervated by the axillary nerve
What muscles form the rotator cuff?
Subscapularis, supraspinatus, infraspinatus and teres minor muscles - form the rotator cuff/musculotendinous which helps keep the head of the humerus close to the glenoid fossa, stabilizing the shoulder joint during abduction and rotation of upper limb.
