Action, Innervations & Attachments - Shoulder/Scapula Region Flashcards
What is the proximal and distal attachment of the sternocleidomastoid?
Proximal attachment: (1) Upper border of manubrium (sternum); (2) Upper border of clalvicle
Distal attachment: Mastoid process of temporal bone & superior nuchal line of occipital bone
The sternocleidomastoid is innervated by which nerve?
Spinal accessory nerve (XI) C1-C3
What is the action of the sternocleidomastoid?
Bilaterally: flexes neck
Unilaterally:
- contralaterally rotates neck
- ipsilaterally laterally flexes neck
- extends head & neck
Note: Contralaterally: having to do with opp side; Ipsilaterally: same side
How to achieve strong activation of sternocleidomastoid muscle for palpation?
- Head is rotated to one side
- resistance is given to lateral flexion of the head to the opp side
Basically, ask patient to look to (e.g.) left, then look down, the sternocleidomastoid muscle will pop out
What do the erector spinae consist of?
From medial to lateral (closest to the spine to furthest from spine)
- Spinalis
- Longissimus
- Iliocostalis
Thoracolumbar aponeurosis ?
Where are the attachments of the erector spinae?
Spinous processes, transverse processes, posterior ribs
From occiput to sacrum & ilium
The erector spinae is innervated by which nerves?
Many dorsal rami of spinal nerves
What is the action of the erector spinae?
Bilaterally: Extends spine
Unilaterally: Ipsilaterally laterally flexes & rotates spine
How to palpate the erector spinae?
- Observe & palpate in the lower thoracic & lumbar area (bc rhomboids & trapezius cover thoracic erector spinae)
- Patient in prone, instruct to extend the thoracolumbar spine (basically back extension)
Where is the proximal and distal attachments of the rectus abdominis?
Proximal attachment: Xiphoid process (sternum) & adjacent costal cartilages
Distal attachment: Pubic bones, near symphysis pubis
The rectus abdominis is innervated by which nerves?
Ventral portions of intercostal nerves T5-T12
What is the action of the rectus abdominis?
Flexes trunk
Where is the proximal and distal attachments of the external abdominal oblique?
Proximal attachment: Anterolateral ribs
Distal attachment: Aponeurosis to the linea alba, iliac crest
The external abdominal oblique is innervated by which nerves?
Lower intercostal nerves T7-T12
What is the action of the external abdominal oblique?
Bilaterally: Flexes trunk without rotation
Unilaterally:
Contralateral rotates
Ipsilaterally laterally flexes trunk
How to palpate the external abdominal obliques?
Patient supine
Attempt to sit up (flex trunk) with contralateral rotation (Side crunch)
What are the proximal and distal attachments of the serratus anterior?
Proximal attachment: Anterior & superior aspects of 1st to 8th ribs
Distal attachment: Anterior surface of vertebral border of scapula
The serratus anterior is innervated by which nerves?
Long thoracic nerve (C5-C7)
What is the action of the serratus anterior?
Protracts & upwardly rotates scapula
How to palpate the serratus anterior?
What is the proximal and distal attachment of the trapezius?
Proximal attachment: Medial one-third of superior nuchal line, external occipital protuberance, ligamentum nuchae, spinous processes C7-T12
Distal attachment: Posterior border of lateral one-third of clavicle, acromion, spine of scapula
The trapezius is innervated by which nerve?
Spinal accessory nerve (C3-C4 and spinal portion of cranial nerve XI)
What is the action of the trapezius?
Upper fibers: Elevates & upwardly rotates scapula; extends, laterally flexes, and contralaterally rotates neck (scapula protraction)
Middle fibers: Upwardly rotates & adducts scapula
(scapula retraction)
Lower fibers: Upwardly rotates, adducts, and depresses scapula
(scapula depresson)
What is the proximal and distal attachment of the rhomboids major and minor?
Proximal attachment: Ligamentum nuchae, spinous processes C7-T5
Distal attachment: Vertebral (medial) border of scapula
