Lesson 8 Spinal Cord Flashcards
(198 cards)
1
Q
What nerve roots originate the common fibular (peroneal) nerve?
A
L4, L5, S1, S2, S3
The common fibular nerve is part of the lumbosacral plexus.
2
Q
Which muscle does the common fibular nerve supply?
A
Biceps femoris (short head)
The common fibular nerve is responsible for innervating this specific muscle.
3
Q
What is the origin of the deep fibular nerve?
A
Common fibular (peroneal) nerve
This nerve innervates muscles in the anterior compartment of the leg.
4
Q
List the muscles innervated by the deep fibular nerve.
A
- Tibialis anterior
- Fibularis tertius
- Extensor digitorum longus
- Extensor hallucis longus
- Extensor digitorum brevis
These muscles are primarily responsible for dorsiflexion and toe extension.
5
Q
What is the sensory innervation provided by the deep fibular nerve?
A
Great and second toes
This nerve provides sensation to the skin in this region.
6
Q
What muscles does the superficial fibular nerve supply?
A
- Fibularis longus
- Fibularis brevis
These muscles are involved in plantar flexion and eversion of the foot.
7
Q
What area does the superficial fibular nerve provide cutaneous innervation to?
A
Dorsal anterior third of leg and dorsum of the foot
This nerve supplies sensation to the skin over these areas.
8
Q
What is the origin of the tibial nerve?
A
L4 through S3
The tibial nerve arises from the lumbosacral plexus.
9
Q
List the muscles innervated by the tibial nerve.
A
- Adductor Magnus
- Biceps femoris (long head)
- Semimembranosus
- Semitendinosus
- Popliteus
- Gastrocnemius
- Soleus
- Flexor digitorum longus
- Flexor hallucis longus
- Tibialis posterior
These muscles are involved in knee flexion and foot plantar flexion.
10
Q
What are the cutaneous innervations provided by the sural nerve?
A
Lateral foot anteriorly and posterior leg and foot
The sural nerve provides sensory innervation to these regions.
11
Q
What is the function of the spinal cord?
A
Carries out integrative functions and communicates with the brain
The spinal cord is part of the central nervous system.
12
Q
What structures are associated with each spinal segment?
A
A pair of spinal nerves
Each spinal segment has a predictable organization of gray and white matter.
13
Q
What is the cauda equina?
A
A tuft of nerves below the lumbosacral enlargement
It consists of the nerve roots that extend below the termination of the spinal cord.
14
Q
What are the three meningeal membranes surrounding the spinal cord?
A
- Dura mater
- Arachnoid mater
- Pia mater
These membranes protect the spinal cord and provide structural support.
15
Q
What is the gray matter of the spinal cord shaped like?
A
A butterfly
The gray matter consists of nerve cell bodies and is surrounded by white matter.
16
Q
What is the anterior median fissure?
A
A deep invagination in the anterior column of the spinal cord
It separates the two halves of the spinal cord.
17
Q
What is the role of sensory neurons in the reflex arc?
A
They synapse with interneurons or directly with motor neurons
This allows for rapid response to stimuli.
18
Q
True or False: The stretch reflex involves a sensory neuron, an interneuron, and a motor neuron.
A
True
In a monosynaptic reflex, the sensory neuron connects directly to the motor neuron.
19
Q
What is the function of the femoral nerve?
A
Innervates muscles that extend the knee
It originates from L2, L3, and L4.
20
Q
What does the sciatic nerve consist of?
A
Tibial and common fibular (peroneal) nerves
These two nerves are bound together within the same sheath in the thigh.
21
Q
What is the origin of the quadriceps femoris muscle?
A
Pelvis
The quadriceps femoris muscle originates from the pelvis and becomes the patellar tendon and ligament with the patella inside.
22
Q
What sensory structure is marked as 1 in the context of the quadriceps femoris muscle?
A
Muscle spindle
The muscle spindle is where the sensory stimulus originates.
23
Q
What is the role of the alpha motor neuron in the stretch reflex?
A
Innervates muscle fibers
The alpha motor neuron receives synapses from sensory neurons and is responsible for muscle contraction.
24
Q
Fill in the blank: The __________ reflex is shown by the extension of the leg.
A
Stretch
The stretch reflex results in the extension of the leg.
25
What is the function of the Golgi tendon organ?
Detects tension in tendons
## Footnote
The Golgi tendon organ sends sensory signals to the spinal cord in response to increased tension.
26
What is the origin of the axillary nerve?
Posterior cord of brachial plexus
## Footnote
The axillary nerve arises from the posterior cord and innervates specific muscles in the shoulder.
27
Which muscles are innervated by the radial nerve?
* Long head of triceps brachii
* Lateral head of triceps brachii
* Brachioradialis
* Extensor carpi radialis longus
* Extensor carpi radialis brevis
* Anconeus
* Supinator
* Extensor digitorum
* Extensor digiti minimi
* Extensor carpi ulnaris
* Extensor indicis
* Abductor pollicis longus
* Extensor pollicis brevis
* Extensor pollicis longus
## Footnote
The radial nerve controls movement and sensation in the posterior arm and forearm.
28
True or False: The ulnar nerve innervates the flexor carpi ulnaris.
True
## Footnote
The ulnar nerve supplies the flexor carpi ulnaris and other muscles in the forearm.
29
What is the primary function of the median nerve?
Controls forearm flexors and hand muscles
## Footnote
The median nerve innervates various muscles including the thenar muscles and flexor digitorum superficialis.
30
List the nerve roots that form the obturator nerve.
* L2
* L3
* L4
## Footnote
The obturator nerve emerges from the lumbosacral plexus and innervates specific thigh muscles.
31
What is the origin of the femoral nerve?
L2, L3, L4
## Footnote
The femoral nerve originates from the lumbar plexus and innervates the anterior compartment of the thigh.
32
What are the major branches of the brachial plexus?
* Axillary nerve
* Radial nerve
* Musculocutaneous nerve
* Median nerve
* Ulnar nerve
## Footnote
These branches innervate various muscles of the shoulder, arm, and hand.
33
Fill in the blank: The __________ nerve originates from L5 and supplies the gluteal muscles.
Superior gluteal
## Footnote
The superior gluteal nerve innervates the gluteus medius and minimus.
34
What is the function of the inferior gluteal nerve?
Innervates gluteus maximus
## Footnote
The inferior gluteal nerve is responsible for the motor function of the gluteus maximus muscle.
35
What does the term 'lumbosacral trunk' refer to?
Nerve roots from L5
## Footnote
The lumbosacral trunk connects the lumbar and sacral plexuses.
36
True or False: The sciatic nerve is the largest nerve in the body.
True
## Footnote
The sciatic nerve is formed from L4 to S3 and innervates the posterior thigh and all of the leg and foot.
37
What is the sensory innervation of the ulnar nerve?
Medial third of hand
## Footnote
The ulnar nerve provides sensory innervation to the little finger and the medial half of the ring finger.
38
What is the cutaneous distribution of the median nerve?
Lateral two-thirds of the palm
## Footnote
The median nerve provides sensory innervation to the thumb, index, middle fingers, and part of the ring finger.
39
What gives out branches that combine with other nerve roots to form the nerves?
Nerve root
## Footnote
Nerve roots emerge from the spinal cord and are responsible for forming the peripheral nerves.
40
Which nerves branch from C1 and C2?
Lesser occipital nerve
## Footnote
The lesser occipital nerve is involved in sensory innervation of the scalp.
41
What nerve branches from C2 and C3?
Greater auricular nerve
## Footnote
This nerve provides sensory innervation to parts of the ear and skin over the parotid gland.
42
Which nerve supplies the sternocleidomastoid muscle?
Nerve to sternocleidomastoid muscle
## Footnote
This nerve branches from C2 and the accessory nerve.
43
What is the function of the transverse cervical nerve?
It extends as a branch to infrahyoid muscles
## Footnote
The transverse cervical nerve branches from C3.
44
What are the roots of ansa cervicalis?
Superior root and inferior root
## Footnote
The superior root has C1 branches, while the inferior root has C3 branches.
45
Which nerve branches are responsible for innervating the trapezius muscle?
Branches from C4 and C5
## Footnote
The trapezius muscle is involved in shoulder movement and stabilization.
46
From which cervical nerves does the phrenic nerve originate?
C3, C4, C5
## Footnote
The phrenic nerve is crucial for diaphragm movement and respiratory function.
47
What is the hypoglossal nerve associated with?
C1 nerve root
## Footnote
The hypoglossal nerve is responsible for tongue movement.
48
What emerges from the spinal cord to form the dorsal root?
Rootlets
## Footnote
Rootlets are small projections that join to form the dorsal root.
49
What do the dorsal and ventral roots combine to form?
Spinal nerve
## Footnote
The spinal nerve further branches into dorsal and ventral rami.
50
What is the function of the dorsal ramus of the spinal nerve?
It innervates the muscles and skin of the back
## Footnote
The dorsal ramus supplies sensory and motor functions to the posterior body.
51
What is the main role of the ventral ramus of the spinal nerve?
It innervates the anterior and lateral body wall and limbs
## Footnote
The ventral ramus contributes to the formation of plexuses.
52
What does the communicating ramus connect?
Two ventral rami
## Footnote
The communicating ramus is associated with the sympathetic nervous system.
53
What is the role of the splanchnic nerve?
It carries autonomic fibers to the abdominal and pelvic organs
## Footnote
Splanchnic nerves arise from the sympathetic chain.
54
What happens to the sensory neuron when a pin pierces the foot?
It travels to the spinal cord via the dorsal root
## Footnote
This initiates the withdrawal reflex.
55
In the withdrawal reflex, what does the sensory neuron form a synapse with?
An excitatory interneuron
## Footnote
This interneuron then activates the alpha motor neuron for muscle contraction.
56
What is reciprocal innervation?
The process where an interneuron inhibits the extensor muscle while activating the flexor muscle
## Footnote
This allows for coordinated movement during reflex actions.
57
What characterizes the crossed extensor reflex?
It involves the contralateral activation of extensor muscles
## Footnote
This reflex helps maintain balance when one limb is withdrawn.
58
What is the function of the ascending axon in spinal cord reflexes?
It crosses the midline and travels up through the ascending tract
## Footnote
This allows sensory information to reach the brain.
59
What covers the spinal nerve?
Epineurium
## Footnote
The epineurium is the outermost layer that protects the nerve.
60
What is the structure of a fascicle in a spinal nerve?
It contains endoneurium and is surrounded by perineurium
## Footnote
Fascicles are bundles of axons within a nerve.
61
How are spinal nerves categorized?
Cervical, thoracic, lumbar, sacral, coccygeal
## Footnote
Each category has a specific number of nerve pairs.
62
What is the function of C1 through C4 spinal nerves?
Head movement and diaphragm movement
## Footnote
These nerves play a crucial role in respiratory function.
63
What is spinal stenosis?
Narrowing of the spinal canal leading to nerve compression
## Footnote
Symptoms may include pain and weakness.
64
What is encephalitis?
Inflammation of the brain, often caused by a virus
## Footnote
Symptoms can include fever and convulsions.
65
What is meningitis?
Inflammation of the meninges, usually due to infection
## Footnote
Symptoms include neck stiffness and headache.
66
What causes tetanus?
Bacterial neurotoxin affecting lower motor neurons
## Footnote
It leads to muscle rigidity and spasms.
67
What is multiple sclerosis?
An autoimmune condition characterized by demyelination
## Footnote
Symptoms include exaggerated reflexes and tremors.
68
What is neuralgia?
Severe nerve pain along the pathway of a nerve
## Footnote
It can result from inflammation or nerve damage.
69
What is diabetic neuropathy?
Nerve damage due to high blood sugar levels
## Footnote
It often results in pain or numbness in extremities.
70
What is myasthenia gravis?
An autoimmune disorder affecting acetylcholine receptors
## Footnote
It leads to muscle weakness and fatigue.
71
How many pairs of spinal nerves are there?
Thirty-one pairs of spinal nerves
72
Where does the first pair of spinal nerves exit the vertebral column?
Between the skull and atlas
73
How many pairs of cervical spinal nerves are there?
Eight pairs
74
What is a dermatomal map?
A skin area supplied with sensory innervation by spinal nerves
75
What does the dorsal ramus innervate?
Deep muscles of the trunk and skin near the midline of the back
76
What is the function of the ventral ramus?
Innervation depends upon which part of the spinal cord is considered
77
What are intercostal nerves?
Nerves that innervate the intercostal muscles and the skin over the thorax
78
Which plexus is formed by the ventral rami of C1 to C4?
Cervical plexus
79
Which plexus is formed by the ventral rami of C5 to T1?
Brachial plexus
80
What is the epineurium?
The connective tissue that surrounds the entire nerve
81
What does the phrenic nerve innervate?
Diaphragm
82
What muscles does the ansa cervicalis serve?
Infrahyoid muscles
83
Fill in the blank: The __________ is a group of related disorders involving compression of nerves and vessels in the thoracic outlet region.
Thoracic outlet syndrome
84
Which nerve is commonly affected in Carpal Tunnel Syndrome?
Median nerve
85
Name the branches of the brachial plexus.
* Axillary
* Radial
* Musculocutaneous
* Ulnar
* Median
86
What can cause thoracic outlet syndrome?
Compression of the brachial plexus or subclavian artery/vein
87
What is the cutaneous innervation of the femoral nerve?
Anterior and medial thigh and leg
88
What is the origin of the musculocutaneous nerve?
Lateral cord of brachial plexus, C5–C7
89
True or False: Cervical ribs occur in about 0.5% of the population.
True
90
What is the primary role of the epineurium?
Surrounds the entire nerve
91
What are common risk factors for developing Carpal Tunnel Syndrome?
* Repetitive overhead arm motions
* Droopy shoulders
* Heavy backpacks
* Obesity
* Pregnancy-related joint changes
* Trauma
92
What symptoms did Sarah experience that led to the diagnosis of thoracic outlet syndrome?
Pain, tingling, and numbness in the ring and little fingers of her right hand
93
Fill in the blank: The __________ ramus communicates with the sympathetic chain of ganglia.
Communicating
94
What anatomical structure is involved in Carpal Tunnel Syndrome?
Median nerve
95
What is the function of the lumbar plexus?
Innervates lower limb muscles and skin
96
Where does the spinal cord begin and end?
From the foramen magnum to the second lumbar vertebra.
97
How many pairs of spinal nerves are associated with the spinal cord?
31 pairs of spinal nerves.
98
What are the segments of the spinal cord?
* Cervical
* Thoracic
* Lumbar
* Sacral
99
What is the cervical enlargement responsible for?
Supplying upper limbs.
100
What is the lumbar enlargement responsible for?
Supplying lower limbs.
101
What is the conus medullaris?
Tapered inferior end of the spinal cord.
102
What is the cauda equina?
Origins of spinal nerves extending inferiorly from lumbosacral enlargement and conus medullaris.
103
What are the three layers of meninges surrounding the spinal cord?
* Dura mater
* Arachnoid mater
* Pia mater
104
What is found in the epidural space?
* Blood vessels
* Areolar connective tissue
* Fat
105
What is meningitis?
Inflammation of meninges caused by viral or bacterial infection.
106
What are the main components of the reflex arc?
* Sensory receptor
* Sensory neuron
* Interneuron
* Motor neuron
* Effector organ
107
What are monosynaptic reflexes?
Reflexes with no interneurons.
108
What are polysynaptic reflexes?
Reflexes with multiple synapses and interneurons.
109
What is the function of the stretch reflex?
Muscles contract in response to a stretching force.
110
What is a muscle spindle?
Specialized muscle cells that respond to stretch.
111
What is the role of gamma motor neurons?
Control sensitivity of muscle spindle.
112
What happens in the Golgi tendon reflex?
Prevents contracting muscles from applying excessive tension to tendons.
113
What is reciprocal innervation?
Relaxation of extensor muscle when flexor muscle contracts.
114
What does the crossed extensor reflex do?
Causes extension of opposite lower limb during withdrawal reflex.
115
What is the role of descending tracts from the brain in reflexes?
Carry information to modify the reflex.
116
What is the clinical significance of the stretch reflex?
Assesses spinal cord integrity, peripheral nerve function, and muscle tone.
117
What does the dorsal root ganglion contain?
Collections of cell bodies of pseudo-unipolar sensory neurons.
118
What is spinal stenosis?
Narrowing of spinal canal or area around nerve roots, leading to nerve compression.
119
What is the thecal sac?
Protective membrane surrounding the spinal cord and nerve roots.
120
What is a lumbar puncture used for?
To remove cerebrospinal fluid for examination.
121
What are the two types of reflexes based on development?
* Innate reflexes
* Learned reflexes
122
What is the role of alpha motor neurons?
Cause muscle contraction.
123
What is the significance of the Achilles tendon reflex?
Checks S1 spinal segment integrity.
124
What is a withdrawal reflex?
Removes a body limb from a painful stimulus.
125
What is reduced sensation to light touch and vibration in the feet and lower legs indicative of?
Sensory Examination
## Footnote
This may suggest a neuropathy affecting sensory nerves.
126
What reflex is absent in the described condition?
Achilles tendon reflexes
## Footnote
The absence may indicate lower motor neuron dysfunction.
127
What type of gait is characterized by foot drop?
High-stepping gait
## Footnote
This gait pattern occurs due to weakness in dorsiflexion.
128
What condition is characterized by a high-arched foot?
Pes cavus
## Footnote
This often accompanies neurological disorders.
129
What diagnostic study shows marked reduction in nerve conduction velocities?
Nerve Conduction Study (NCS)
## Footnote
This indicates a demyelinating neuropathy.
130
Which gene mutation is associated with the described condition?
PMP22 gene
## Footnote
Mutations in this gene are linked to Charcot-Marie-Tooth disease.
131
What is spinal stenosis?
Narrowing of spinal canal or area around nerve roots
## Footnote
This can lead to nerve compression and symptoms like pain and numbness.
132
What is encephalitis?
Inflammation of the brain caused by a virus
## Footnote
Symptoms may include fever, coma, and convulsions.
133
What are the symptoms of meningitis?
Stiffness in the neck, headache, and fever
## Footnote
Severe cases can cause paralysis, coma, or death.
134
What is rabies?
Viral disease transmitted by an infected animal
## Footnote
It leads to brain infection resulting in aggression, paralysis, and death.
135
What causes tetanus?
Bacterial neurotoxin affecting lower motor neurons
## Footnote
It leads to muscle rigidity and spasms.
136
What condition is characterized by autoimmune demyelination?
Multiple sclerosis
## Footnote
Symptoms include exaggerated reflexes and tremors.
137
What does anesthesia refer to?
Loss of sensation
## Footnote
It can be a pathological condition or induced temporarily.
138
What is neuritis?
Inflammation of a nerve
## Footnote
Can result in loss of motor function or anesthesia.
139
What is neuralgia?
Nerve pain characterized by severe spasms of pain
## Footnote
Often results from inflammation or nerve damage.
140
What is sciatica?
Neuralgia of the sciatic nerve
## Footnote
Pain radiates down the back of the leg, commonly due to a herniated disk.
141
What is leprosy?
Bacterial disease affecting skin and PNS cells
## Footnote
Characterized by disfiguring nodules and tissue necrosis.
142
What does poliomyelitis primarily damage?
Somatic motor neurons
## Footnote
Leads to paralysis and muscle atrophy.
143
What is diabetic neuropathy?
Damage to nerves due to high blood sugar levels
## Footnote
Symptoms may include pain or numbness in extremities.
144
What is Charcot-Marie-Tooth disease?
Common hereditary neurological disorder
## Footnote
Characterized by muscle weakness and loss of sensation.
145
What is neurofibromatosis?
Genetic disorder with benign tumors along peripheral nerves
## Footnote
Results in skin growths from early childhood.
146
What is myasthenia gravis?
Autoimmune disorder affecting acetylcholine receptors
## Footnote
Leads to muscle weakness and increased fatigue.
147
What is the function of spinal nerves?
Transmit action potentials to and from the spinal cord
## Footnote
They are part of the peripheral nervous system.
148
What does the spinal cord carry out?
Integrative functions and communication with the brain
## Footnote
Each spinal segment has a predictable organization of gray and white matter.
149
What are the three layers of meninges surrounding the spinal cord?
* Dura mater
* Arachnoid mater
* Pia mater
## Footnote
These layers provide protection to the spinal cord.
150
What is the primary role of the dorsal horn in the spinal cord?
Sensory processing
## Footnote
Contains sensory neurons that receive input from the body.
151
What is a reflex arc?
Pathway that mediates a reflex action
## Footnote
Involves sensory neurons, interneurons, and motor neurons.
152
What is the knee jerk reflex an example of?
Stretch reflex
## Footnote
It involves the quadriceps muscle and is tested using a reflex hammer.
153
What does the Golgi tendon reflex involve?
Inhibition of alpha motor neurons
## Footnote
It protects muscles from excessive tension.
154
What is the withdrawal reflex?
A protective reflex that withdraws a limb from a harmful stimulus
## Footnote
Involves sensory neurons and interneurons to activate flexor muscles.
155
What is reciprocal innervation?
Simultaneous contraction of one muscle and relaxation of its antagonist
## Footnote
It occurs during withdrawal reflexes to allow coordinated movement.
156
What type of neuron forms a synapse with an alpha motor neuron that supplies the flexor hamstring muscles?
Excitatory interneuron
## Footnote
This interneuron is part of the withdrawal reflex mechanism.
157
What is the term for the reflex that involves the flexor muscles contracting while the extensor muscles are inhibited?
Reciprocal innervation
## Footnote
This occurs during the withdrawal reflex.
158
Which reflex involves the sensory neuron stimulating muscles on the opposite side of the body?
Crossed extensor reflex
## Footnote
This reflex is activated when a pin pierces the foot, causing the opposite leg to extend.
159
What are the two branches of the sensory neuron that enters the spinal cord?
* Ascending axon
* Interneuron
## Footnote
The ascending axon travels to the brain while the interneuron connects to motor neurons.
160
What is the outer covering of a spinal nerve called?
Epineurium
## Footnote
It contains loose connective tissue.
161
List the types of spinal nerves.
* Cervical nerves
* Thoracic nerves
* Lumbar nerves
* Sacral nerves
* Coccygeal nerve
## Footnote
Each type has specific functions and innervates different body regions.
162
What is the function of the phrenic nerve?
Innervates the diaphragm
## Footnote
It is crucial for breathing.
163
Fill in the blank: The __________ is the tuft of nerves at the end of the spinal cord.
cauda equina
## Footnote
This structure is located at the level of L4.
164
What do the cervical nerves C1 through C4 primarily control?
Head movement and diaphragm movement
## Footnote
These nerves are essential for basic motor functions.
165
True or False: The radial nerve is responsible for extending the elbow and wrist.
True
## Footnote
The radial nerve innervates various muscles involved in extension.
166
What is the main function of the axillary nerve?
Innervates the teres minor and deltoid muscles
## Footnote
It is involved in arm movement.
167
Identify the components of the brachial plexus.
* C5-C6: Upper trunk
* C7: Middle trunk
* C8-T1: Lower trunk
* Anterior and posterior divisions
* Lateral, medial, and posterior cords
## Footnote
Each component gives rise to specific nerves.
168
What type of neuron carries sensory information into the spinal cord?
Sensory neuron
## Footnote
It enters through the dorsal root.
169
What is the primary role of the interneuron in spinal reflexes?
Connects sensory and motor neurons
## Footnote
It facilitates the reflex response.
170
What are the roots of the cervical plexus responsible for?
* Lesser occipital nerve
* Greater auricular nerve
* Transverse cervical nerve
* Phrenic nerve
## Footnote
These nerves control various neck and shoulder movements.
171
What does the medial cord of the brachial plexus give rise to?
* Medial brachial cutaneous nerve
* Medial antebrachial cutaneous nerve
* Ulnar nerve
## Footnote
These nerves provide sensory and motor innervation.
172
What anatomical structure do the spinal nerves emerge from?
Intervertebral foramen
## Footnote
This is the opening between vertebrae.
173
What is the function of the Extensor carpi radialis longus?
Extends and abducts wrist
## Footnote
This muscle assists in the movement of the wrist.
174
Which nerve innervates the coracobrachialis, biceps brachii, and brachialis?
Musculocutaneous Nerve
## Footnote
Originates from the lateral cord of the brachial plexus, C5–C7.
175
What is the cutaneous supply of the musculocutaneous nerve?
Antero posterolateral forearm
## Footnote
Provides sensory innervation to this area.
176
What muscles does the ulnar nerve supply?
* Flexor carpi ulnaris
* Flexor digitorum profundus
* Adductor pollicis
* Hypothenar muscles
* Dorsal and palmar interossei
* Two medial lumbricals
## Footnote
Innervates muscles responsible for finger movement and wrist flexion.
177
What is the sensory innervation area of the ulnar nerve?
Medial third of hand, little finger, and medial half of ring finger
## Footnote
This nerve provides sensory information to these specific areas.
178
Fill in the blank: The median nerve originates from the _______ and _______ cords of the brachial plexus.
medial, lateral
## Footnote
It includes nerve roots from C5 to T1.
179
Which muscles does the median nerve innervate?
* Palmaris longus
* Pronator teres
* Flexor carpi radialis
* Flexor digitorum superficialis
* Flexor digitorum profundus (part)
* Flexor pollicis longus
* Pronator quadratus
* Thenar muscles
* Two lateral radial lumbricals
## Footnote
These muscles are primarily responsible for flexion and pronation of the forearm and hand.
180
What is the cutaneous distribution of the median nerve?
Anteriorly and posteriorly lateral two-thirds of the hand
## Footnote
Provides sensory innervation to these areas.
181
Which nerve roots give rise to the obturator nerve?
L2, L3, L4
## Footnote
It emerges from the lumbosacral plexus.
182
What is the primary function of the femoral nerve?
* Flexes hip
* Extends knee
## Footnote
Innervates major muscles of the thigh including psoas major and quadriceps.
183
What area does the femoral nerve provide sensory innervation to?
Anteromedial thigh and leg
## Footnote
Supplies sensory information to these regions.
184
What muscles does the tibial nerve innervate?
* Adductor Magnus
* Biceps femoris (long head)
* Semimembranosus
* Semitendinosus
* Popliteus
* Gastrocnemius
* Soleus
* Flexor digitorum longus
* Flexor hallucis longus
* Tibialis posterior
## Footnote
Responsible for movements of the posterior thigh and leg.
185
What is the cutaneous innervation area of the tibial nerve?
Lateral foot anteriorly and posterior leg and foot
## Footnote
Provides sensory information to these areas.
186
Fill in the blank: The common fibular (peroneal) nerve originates from the _______ through _______ nerve root.
L4, S3
## Footnote
It is part of the lumbosacral plexus.
187
What muscles does the deep fibular nerve innervate?
* Tibialis anterior
* Fibularis tertius
* Extensor digitorum longus
* Extensor hallucis longus
* Extensor digitorum brevis
## Footnote
These muscles are primarily responsible for dorsiflexion and toe extension.
188
Which area does the superficial fibular nerve provide sensory innervation to?
Dorsal anterior third of leg and dorsum of the foot
## Footnote
Supplies sensory information to this region.
189
What is the origin of the iliohypogastric and ilioinguinal nerves?
L1
## Footnote
These nerves arise from the lumbar plexus.
190
What is the function of the superior gluteal nerve?
Innervates gluteus medius and minimus
## Footnote
Important for hip abduction.
191
What spinal levels does the Obturator nerve originate from?
L 2, L 3, and L 4
## Footnote
The Obturator nerve is responsible for innervating the medial compartment of the thigh.
192
Which spinal level does the lumbosacral trunk originate from?
L 5
## Footnote
The lumbosacral trunk contributes to the formation of the sacral plexus.
193
What are the spinal levels for the superior gluteal nerve?
L 5, S 1, and S 2
## Footnote
The superior gluteal nerve innervates the gluteus medius, gluteus minimus, and tensor fasciae latae.
194
From which spinal level does the inferior gluteal nerve originate?
S 1
## Footnote
The inferior gluteal nerve primarily innervates the gluteus maximus.
195
What are the spinal levels for the sciatic common fibular (peroneal) nerve?
L 4, L 5, S 1, and S 2
## Footnote
This nerve is responsible for innervating the muscles of the anterior and lateral compartments of the leg.
196
What spinal levels does the sciatic tibial nerve originate from?
L 5, S 1, S 2, and L 3
## Footnote
The tibial nerve innervates the posterior compartment of the leg and the plantar aspect of the foot.
197
Which spinal levels does the posterior femoral cutaneous nerve originate from?
S 2 and S 3
## Footnote
This nerve provides sensory innervation to the skin of the posterior thigh.
198
What are the spinal levels for the pudendal nerve?
S 2 and S 4
## Footnote
The pudendal nerve is crucial for innervating the perineum and external genitalia.
