Descending tracts carry what kind of impulses?

What direction to efferent impulses travel?

What is the final destination?

The ventral (anterior) horn neurons give rise to fibers that innerate skeleton.  They are _________ _________ neurons

Brain

dorsal (posterior) horn cells

Spinal cord segments C5 - C8 and T1 give rise to nerves that supply innervation to the _______ _______ and _______ nerves of the ________ _________

radial, ulnar, and median

upper lim

Spinothalamic tract (also called lateral spinothalamic tract)

posterior (or dorsal) column tract

Journey of a pain impulse:

Burn your finger:

impulse travels from nerve ending in skin through a nerve fiber ---> ________ ---> dorsal root ---> dorsal horn __________ and __________

DRG (dorsal root ganglion)

neurons

interneurons

Pain sensation: Use sharp and dull ends of cotton tip applicator and compare both sides in same location.

Temperature sensation is tested only if pain is abnormal.

proprioception

two-point discrimination

vibration

position

light touch

True or false: The posterior (dorsal) column tract is ipsilateral in the spinal cord.

Contralateral.

The fibers travel to the brain stem, then cross and synapse on the contralateral postcentral gyrus of the parietal lobe.

Where does the sensory pathway for fine touch "cross over?"

The romberg test assesses:

Cerebellar function

Posterior (dorsal) column tract function

Ask patient to stand with heels together, first with eyes open, then with eyes closed.

Note any excessive postural swaying or loss of balance.

proprioceptive deficit

(sensory ataxia)

= dorsal column damage.

The Finger-nose-finger test assesses function of what?

What would be the sensory findings if a patient has a completely transected cord?
Below the level of the lesion?

Above the level of the lesion?

What would be the sensory findings if only one half of the spinal cord was affected? 
Below thelevel of the lesion?

Above the level of the lesion?

• Contralateral loss of pain and temperature below the level of the lesion (spinothalamic tract)
• Ipsilateral loss of 2PD, vibration, proprioception, etc. below the level of the lesion (dorsal column tract). 

Cerebral cortex

spinal cord

Precentral gyrus

frontal

Dorsal

ventral

Dorsal

anterior (ventral)

A patient has hyperreflexia, positive babinski, and clonus present.  Is this indicative of an UMN or LMN lesion?

What is an example of a disease affecting only the anterior horn?

contralateral spastic paralysis

(Brain = UMN = spastic paralysis)

ipsilateral spastic paralysis below the level of lesion.

(Tract in cord = UMN = spastic paralysis)

hyporeflexia

flaccid muscle tone, paralysis

• Intact sensory (afferent) fiber
• Functional synapse in the spinal cord
• Motor (efferent) fiber to the muscle
• Intact NMJ
• Competent muscle

It is an involuntary response to a stimulus mediated by the spinal cord.

It is not voluntarily controlled by the cerebral cortex.

Reflex pathway:

Sensory endings in muscle --> DRG --> dorsal root --> synapse in cord with motor neurons in ventral root --> spinal nerve --> back to the same muscle

(Just a concept - no back to this card)

reinforcement technique. 

Gets pt.s mind off of the test, relaxes muscle, then reflex can be tested

What is an abnormal plantar reflex?

What are the 3 factors of the Glasgow Coma Scale?

eye opening, verbal response, motor response. 

Lowest score = 3, Highest = 15

15 is "good."  May be discharged with a normal CT scan. 

3% may deteriorate within 48 hrs post-injury

9-13

Mortality less than 20%, Long-term disability as high as 50%. 

About 10% progress to servere THI

Severe THI.  Death approaches 40% within 48 hours. 

Fewer than 10% of Severe THI cases make even a moderate recovery... Sucks.