Neurological

Question 1

Cervical Nerve Plexus (C1-C4)

Answer 1

Portion of the phrenic nerve
Innervates muscles and skin of a portion of the head, neck, and upper shoulders; diaphragm

Question 2

Brachial plexus (C5-C8 and T1)

Answer 2

Phrenic, circumflex, musculocutaneous, ulnar, median, and radial nerves

Innervates shoulder, arm, and hand; diaphragm

Question 3

Lumbar plexus (L1-L4)

Answer 3

Femoral cutaneous, femoral and genitofemoral branches

Innervates anterior abdominal wall and genitalia; thigh and leg

Question 4

Sacral plexus (L4 and L5, S1-S4)

Answer 4

Tibial, common peroneal, sciatic, and pudendal nerves

Innervates skin of the leg, muscles of the posterior thigh, leg, and foot

Question 5

CN III: Oculomotor Nerve Compression

Answer 5

A dilated, non reactive (fixed) pupil indicates that the control for papillary constriction is not functioning. The parasympathetic fibers of the oculomotor nerve control papillary constriction
Most common cause is oculomotor nerve compression. If dilated pupil is a new finding, notify the physician immediately.

Question 6

Horner’s Syndrome

Answer 6

One pupil is larger than the other although both pupils react to light. The eyelid on the same side as the smaller pupil droops (ptosis)
Inability to sweat (anhidrosis) on the same side of the face as the ptosis is common
Interruption of the ipsilateral sympathetic innervation to the pupil.

Question 7

Midbrain Damage

Answer 7

Both pupils are at midposition and nonreactive to light. No parasympathetic or sympathetic innervation. Associated with midbrain infarct or transtentorial herniation.

Question 8

Pontine Damage

Answer 8

Very small (pinpoint), nonreactive pupils
Indicates focal damage of the pons, often due to hemorrhage or ischemia

Bilateral pinpoint pupils may occur from opioid overdose, so this possibility should be ruled out

Question 9

Muscle Strength Scale

Answer 9

5 points: full strength, no deficit or weakness
4 points: able to lift extremity against gravity and maintain position without wavering
3 points: able to lift extremity against gravity, but wavers and cannot sustain
2 points: able to slide along support surfaces such as bed or chair
1 point: flicker or trace movement
0 points: no movement

Question 10

Decorticate posturing (elbows bent toward the chest)

Answer 10

Flexing response
Disruption of corticospinal pathways
Loss of cerebral cortex influence over movement

Question 11

Decerebrate posturing (extension response)

Answer 11

Damage to deeper cerebral hemispheres and upper brain stem
Indicates severe brain dysfunction with poor prognosis

Question 12

Subarachnoid Hemorrhage

Answer 12

Sudden, violent headache
Altered LOC
Signs of increased ICP
N/V
Meningeal irritation: Kernig’s sign (resistance and pain when patient’s leg is flexed at hip and knee) and Brudinski’s sign (flexion of the hips and knees in response to passive flexion of neck)
Focal signs depending on location of bleeding
Bloody CSF