Muscle Actions and Innervations Flashcards
Innervation of the trapezius
spinal accessory nerve (CNXI)
Actions of the trapezius
- elevates, retracts, and depresses scapula
- extends neck
- superiorly rotates glenohumeral joint
Innervation of the latissimus
thoracodorsal nerve
Actions of the latissimus dorsi
- extension of glenohumeral joint
- medial rotation of glenohumeral joint
- adduction of glenohumeral joint
Innervation of the rhomboids
dorsal scapular nerve
Actions of the rhomboids
retraction and elevation of scapula
Levator scapulae innervation
dorsal scapular nerve
Actions of the levator scapulae
elevates scapula only
Actions of the splenius capitis
bilateral: head extension
actions of the splenius cervicis
unilateral: lateral flexion and rotation of head
Erector spinae innervation
dorsal rami of spinal nerves
Actions of erector spinae
chief extensor of the vertebral column
Actions of the levator costarum
elevate ribs for deep inspiration
Deltoid innervation
axillary nerve
Actions of the deltoid
- flexion and medial rotation of glenohumeral joint
- abduction
- extension and lateral rotation of glenohumeral joint
Supraspinatus innervation
suprascapular nerve
supraspinatus actions
initiates first 15 degrees of abduction
infraspinatus innervation
suprascapular nerve
infraspinatus actions
laterally rotates glenhohumeral joint
teres minor innervation
axiillary nerve
teres minor actions
laterally rotates glenohumeral joint
Subscapularis innervation
subscapular nerve (upper/lower)
subscapularis actions
medially rotates glenohumeral joint
Innervation of teres major
lower subscapular nerve
Actions of teres major
- adduction
- medially rotates glenohumeral joint
Innervation of serratus anterior
long thoracic nerve
Actions of serratus anterior
abducts and rotates scapula upward
Serratus posterior superior actions
elevates upper ribs
serratus posterior inferior actions
pulls down lower ribs
External intercostals actions
aids forced inspiration by elevating ribs
Rectus capitis posterior major and minor actions
extends head and neck
Obliqus capitis inferior actions
rotates head
Obliqus capitis superior actions
- bilateral: extends neck
- unilateral: lateral flexion to same side
Innervation of Gluteus maximus
inferior gluteal nerve
actions of gluteus maximus
- extends thigh and trunk
- laterally rotates hip joint
Innervation of gluteus medius and minimus
superior gluteal nerve
Actions of gluteus medius and minimus
-abduct hip joint when contralateral lower limb is raised
Actions of the piriformis
laterally rotates and abducts thigh
Actions of the gemellus superior, obturator internus, gemellus inferior, quadratus femoris
laterally rotate thigh
Actions of biceps femoris, semitendinosus, and semimembranosus
- extension of hip joint
- flexion of knee joint
Gastrocnemius innervation
tibial nerve
gastrocnemius actions
- plantar flexion of foot
- knee flexion
Soleus innervation
tibial nerve
soleus actions
plantar flexion of foot
Innervation of tibialis posterior
tibial nerve
Actions of the tibialis posterior
- inversion and assists in the plantar flexion of the foot at the ankle
- major role in supporting the medial arch of the foot
Innervation of flexor hallucis longus
tibial nerve
Actions of the flexor hallucis longus
- inversion and assists in the plantar flexion of the foot at the ankle
- flex the great toe
Flexor digitorum longus innervation
tibial nerve
Actions of the digitorum longus innervation
- inversion and assists in the plantar flexion of the foot at the ankle
- flexion of phalanges
Fibularis longus and brevis innervation
superficial fibular nerve
Actions of the fibularis longus and brevis
foot eversion
Triceps brachii long head actions
-extension of the arm at the shoulder, adduction of the arm at the shoulder, extension of the forearm at the elbow
Triceps brachii innervation
radial nerve
Actions of the triceps brachii lateral head
extension of the forearm at the elbow