Lecture 29 Shoulder Flashcards
What does the brachial plexus consist of?
- ventral rami of C5, C6, C7, C8, T1
what provides the motor innervation to the trapezius?
- CN11
What provides the sensory innervation to the trapezius?
- C3 and 4
What innervates the latissimus dorsi?
- thoracodorsal nerve
What makes up layer one of posterio axio appendicular muscles?
- trapezius and latissimus dorsi
What makes up layer 2 of posterio axio appendicular muscles?
- levator scapulae
- rhomboid minor
- rhomboid major
What makes up layer 3 of posterior axio-appendicular muscles
- serratus posterior superior and inferior
what nerve innerates the rhomboid major and minor?
- dorsal scapular nerve
What nerves innervate levator scapulae?
- 3rd and 4th cervical spinal nerves and dorsal scapular nerve
What is the proximal attachment of the trapezius?
- external occipital protuberance of skull, nuchal ligament, spinous processes of C7-T12 vertebrae
What is the distal attachment of the trapezius?
- lateral third of clavicle (anterior), acromion, and spine of scapula
What is the function of the trapezius?
- elevates, depresses, and retracts scapula, rotates glenoid fossa superiorly
What is the motor innervation of the trapezius?
- CN 11
What is the sensory innervation of trapezius?
- C3 and C4
Where is the anterior attachment of trapezius?
- lateral 1/3 of clavicle
What is the posterior attachment of trapezius?
- spine and acromion of scapula
what movements can the trapezius facilitate on the scapula?
- elevation/depression
- retraction
- upward rotation
What is the proximal attachment of the latissimus dorsi?
- spinous processes of inferior 6 thoracic vertebrae, thoracolumbar fascia, iliac crest and inferior 3 ribs
What is the distal attachment of the latissimus dorsi?
- floor of intertubercular sulcus (bicipital groove) of humerus
_____ muscle extends, adducts, and medially rotates the humerus; raises torso towards arms during climbing
- latissimus dorsi
What innervates the latissimus dorsi?
- thoracodorsal nerve (from brahcial plexus)
What are the actions of the latissimus dorsi on the arm?
- extends humerus
- adducts humerus
- medially rotates humerus
How does the latissimus dorsi act during a pull up?
- raises torso towards arms when climbinh or doing a pull up (raises or pulls torso up when hands/arm is fixed)
What does the latissimus dorsi do when the torso is fixed?
- pulls humerus down