3 - Muscles of Back Flashcards
What is the muscle found in the picture?
The trapezius
What nerve provides motor innervation of the trapezius?
The accessory nerve
What are the roots of the accessory nerve?
C1 - C6
What are the roots of the accessory nerve specific to sensory function?
C3 and C4
What are the actions of the trapezius?
The upper fibres of the trapezius elevate the scapula and rotate it during abduction of the arm. The middle fibres retract the scapula and the lower fibres pull the scapula inferiorly
How would you test the accessory nerve?
test how well the trapezius is functioning. You can do this by getting the patient to elevate the shoulder against resistance.
What is the muscle shown in the picture?
Latissimus dorsi
What innervates latissimus dorsi?
Thoracodorsal nerve
What actions is the latissimus dorsi responsible for?
Extension of the arm at the shoulder, adduction at the shoulder and medial rotation of the arm
What is the muscle in the picture?
Levator Scapulae
What does Levator Scapulae attach?
Medial border of the scapulae
Where does latissimus Dorsi attach?
attaches to the intertubecular sulcus of the humerus
Where does trapezius attach?
All fibres attach to the posterior surface of the scapula and the clavicle.
What innervates levator scapulae?
Dorsal Scapula nevere
What are the actions of the levator scapulae?
Elevates scapula. Rotates scapula to tilt glenohumeral joint inferiorly
What are the muscles shown in the picture?
The Rhomboids major and minor
Where do the rhomboids attach?
The medial border of the scapula
What are the rhomboids innervated by?
Dorsal scapula nerve
What are the actions of the rhomboids?
Retracts scapula. Rotates scapula to tilt glenohumeral joint inferiorly. Can also fix the scapula to the thoracic wall.
What is the muscle shown in the picture?
Deltoid