Neuromuscular System: Innervation Review

An inability to extend the elbow could result from pathology affecting the: dorsal nerve root of C7 ventral nerve root of C7 dorsal nerve root of C8 ventral nerve root of C6

Efferent fibers that control motor function are located in the ventral nerve root as they exit the spinal cord. The triceps receive their primary innervation from the C7 spinal segment.

T/F: obturatro nerve innervates pectineus

FALSE. femoral nerve

T/F: triceps are innervated by the axillary nerve

FALSE. radial nerve

Paralysis of which nerve gives rise to scapular winging? suprascapular nerve long thoracic nerve subscapular nerve thoracodorsal nerve

Paralysis of which nerve gives rise to scapular winging? suprascapular nerve long thoracic nerve subscapular nerve thoracodorsal nerve

At which of the following sites might the median nerve be compressed? passing through the two heads of the pronator teres passing beneath the pisohamate ligament passing between the two heads of the supinator passing through the canal of Frohse

Pronator syndrome occurs when the median nerve is compressed as it passes through the two heads of the pronator teres. This will affect sensory and motor function of the median nerve.

T/F: piriformis is innervated by sacral plexus

TRUE

T/F: superior gluteal nerve innervates the TFL

TRUE

Deltoid atrophy may be associated with an injury to the: axillary nerve median nerve radial nerve subclavian nerve

The axillary nerve arises from the C5-C6 nerve roots and innervates the deltoid muscle. Damage to the axillary nerve commonly occurs following a fracture to the head of the humerus.

What artery is used as a point of reference when naming the cords of the brachial plexus? axillary artery carotid artery subclavian artery vertebral

The brachial plexus includes three cords (i.e., lateral, medial, posterior) that are named according to their position with respect to the axillary artery.

Which muscle of the lower extremity is not innervated by the tibial nerve? flexor hallucis longus flexor digitorum longus flexor digiti minimi tibialis posterior

The flexor digiti minimi is innervated by the lateral plantar nerve.

Which nerve innervates the cremasteric muscle? ilioinguinal nerve obturator nerve genitofemoral nerve femoral nerve

The genital branch of the genitofemoral nerve arises from the roots of L1 and L2 and innervates the cremaster muscle. The cremaster muscle receives blood supply from the cremasteric artery.

An inability to splay the fingers would indicate damage at which spinal segments? C5-C6 C6-C7 C7-C8 C8-T1

The majority of the intrinsic muscles of the thumb and fingers are innervated at the C8-T1 spinal segments.

Injury to the posterior cord of the brachial plexus could involve all of the following except: thoracodorsal nerve radial nerve axillary nerve musculocutaneous nerve

The musculocutaneous nerve arises from the lateral cord of the brachial plexus. The nerve innervates the coracobrachialis, biceps brachii, and brachialis.

Which muscle is innervated by the femoral nerve? adductor longus iliopsoas quadriceps femoris hamstrings

The quadriceps femoris muscle is located on the anterior portion of the upper leg and serves as the primary extensor of the knee.

Which of the following nerves does not have a connection from all three trunks of the brachial plexus? lower subscapular radial suprascapular thoracodorsal

The suprascapular nerve (C4, C5, C6) extends from the superior trunk of the brachial plexus. The nerve innervates the supraspinatus and infraspinatus muscles.

Which muscle is innervated by the ulnar nerve? anconeus extensor carpi radialis flexor digitorum profundus supinator

The ulnar nerve arises from the medial cord of the plexus and innervates the flexor carpi ulnaris, flexor digitorum profundus, and most of the small muscles of the hand.

wasting of the thenar eminence indicates possible damage to which nerve? a) radial b) ulnar c) median d) axillary e) musculocutaneous

median nerve

the ____ is innervated by the upper and lower subscapular nerves

subscapularis

which 2 nerves innervate muscles that allow for ulnar deviation at the wrist? a) ulnar n. b) radial n. c) musculocutaneous n. d) axillary n. e) median n.

ulnar = flexor carpi ulnaris radial = extensor carpi ulnaris

medial 1/2 flexor digitorum profundus is innervated by

ulnar nerve

which 2 of the following nerves innervate the great toe flexors? a) tibial nerve b) superficial peroneal nerve c) deep peroneal nerve d) medial plantar nerve e) lateral plantar nerve

- medial plantar nerve = FDB, FHB - tibial nerve = FHL, FDL

Which of the following muscles is innervated by the anterior division of the obturator nerve? pectineus adductor magnus adductor longus gracilis

All of the options are innervated by the obturator nerve (L2-L4), but only the adductor longus is innervated by the anterior division. The pectineus is innervated by the obturator nerve in slightly less than 10% of individuals, while most often it is innervated by the femoral nerve.

which 2 nerves originate from the rami of the brachial plexus? a) nerve to subclavius b) dorsal scapular nerve c) long thoracic nerve d) suprascapular nerve e) thoracodorsal nerve

B and C

cremaster muscle

Muscle that pulls the scrotum closer to the body in cold temperatures and relaxes to let the testicles be farther away from the body in warmer weather