3-9 Exam of the Peripheral Nervous System Flashcards
What are some common complaints that warrant an exam of the PNS?
Shooting pain down entire limb
loss of strength
tingling/parasthesias
chicken pox sequelae
What questions should you ask to help take a good history for a neuro-related complaint?
Local or diffuse?
Restricted to NS (nervous system) or includes other symptoms? fracture, subdural hematoma, tumor growth
CNS, PNS or both
Is your professor a guy named Dr. Vosko?
What is the goal of taking a history with a NS related complaint?
Find where lesion is, then develop good differentials.
What is the scope of the PNS?
Cranial nerves
Motor efferents
Sensory afferents
Neuromuscular junction
Muscle itself
What is the scope of the CNS?
Cortex
Basal Ganglia
Brain stem
Cerebellum
Spinal Cord
Generally, what are the basic parts of the NS exam - history and physical?
¢Central Nervous System
Mental Status and Cognition
Coordination
Cranial Nerves (technically peripheral nerves)
¢Peripheral Nervous System
Motor: Strength and Motion
Sensation
Reflexes
What is the origin and course of the upper motor neurons?
¢Upper Motor Neurons: Originate in the cortex to become the motor fibers above the anterior horn of the spinal cord or motor nuclei of the cranial nerves
What is the origin and course of the lower motor neurons?
¢Lower Motor Neurons: Emanate from the anterior horn of the spinal cord and take the motor signal peripherally to the muscle.
¢Peripheral motor sensory system
What are the most common NS-related complaints?
Pain
Weakness
Paresthesia (numbness/tingling)
What are other important parts of a patient history with a NS-related complaint?
¢Associated Features: swelling, rash, spasm, deformities, mental status
Trauma/Surgery/Medications/Supplements
¢Personal/Family History - autoimmune, dystrophies, diabetes, DJD, exposures
What are the most common causes of NS (nervous system) disorders?
Ischemia (arterial stenosis)
Bleeding (TIA,CVA)
Masses (impingement)
Peripheral nervous disorders (MS, Guillian Barre)
Neuromuscular disorders (myasthenia gravis)
Muscular disorders (dystrophies)
What is dyesthesia?
¢Dysesthesia: all types of abnormal sensation including pain regardless of a stimulant being present or not
Often described by patient
What is a paresthesia?
¢Paresthesia: mostly numb, tingling, pins & needles without pain and without apparent stimulus
What is anesthesia, in the context of an NS exam?
oAnesthesia: absence of senstion
What is hypoesthesia?
¢Hypesthesia or hypoesthesia: reduced sensitivity
What is hyperesthesia?
¢Hyperesthesia: Increased sensitivity
What is hyperalgesia?
¢Hyperalgesia: significant pain in response to mildly painful stimulus (sharp)
What is allodynia?
¢Allodynia: non-painful stimulus perceived as painful on the skin, sometimes severe
What are the 5 types of sensation tested in a PNS exam?
Spinothalamic:
¢Pain: pin or sharp end of broken Q-Tip
¢Temperature: Metal hammer handle is cool
¢Light touch: Q-Tip Cotton wisp
Posterior Column:
¢Proprioception (Position): Large Toe: up? down?
¢Vibration: Tuning fork on boney prominence
In addition to types of touch, what 3 other things should be done when testing sensation in a PNS exam?
COMPARE SIDE TO SIDE , proximal and distal in a pattern that covers both dermatomes and major peripheral cutaneous regions.
¢Instructing the patient to close their eyes enhances sensitivity
¢Map out any area found abnormal, find the boundaries
What is being tested during a discriminative sensation exam?
Test of cortical sensory function
¢Stereognosis: Identify an object by feel
¢2-point discrimination
¢Number Identification: Identify shapes/numbers
What 4 things should be tested with a motor exam? On what side should testing be done?
¢Inspection: atrophy
¢Palpation: tone, soft, firm. Spasm?
¢Strength testing: major muscle groups
¢Reflexes: brainstem, superficial, deep, clonus
Testing should always be done bilaterally
What is the scale for muscle strength? What is the scale relative to?
¢Measurement Scale of 0-5
0= no movement
1= muscle twitch without joint movement
2= movement with gravity eliminated
3= full strength against gravity only
4= partial strength against resistance
5= full strength against resistance
Relative to patient’s full, non-pathological strength
Examine and compare bilaterally
How is muscle strength named?
¢Name for joint motions or muscle group
“4/5 left bicep” or “4/5 flexion at left elbow”
What are some DTRs that are commonly tested? How are they tested and what do they signify?
¢Brachioradialis- C5, C6
Point end into proximal muscle belly
Flat end on distal tendon
¢Biceps- C5, C6
Point end onto thumb lying over tendon
¢Triceps- C6, C7
Flat or point end on triceps tendon above olecranon
¢Patellar- L2,3,4
Flat end on patellar tendon below patella above tibia
¢Achilles- S1
Flat end on achilles tendon above calcaneus
What is the grading scale for DTRs?
¢0 = Absent ¢1+ = Diminished ¢2+ = Normal/Average ¢3+ = Mildly over-active ¢4+ = Highly over-active
How does reinforcement work in regards to DTRs?
Reinforcement: engage bilateral muscle groups ABOVE the level being tested to block any run away motor neuron signals going up to enhance the reflex signal.
What are hallmark symptoms of an UMN (upper motor neuron) lesion?
Upper Motor Neuron Lesion
vSpasticity is hallmark (not 100%)
vLoss of dexterity
vUp Going Babinski (abnormal)
vLoss of superficial reflexes
vWeakness without atrophy of muscle
vHyperreflexia of deep tendon reflex (DTR)
¢Paralysis of movement, not muscle
¢Atrophy from disuse, slight
¢Spasticity, hypertonic
What are some common causes of UMN lesions?
Stroke
Multiple Sclerosis Cerebral Palsy Traumatic Brain Injury Amyotrophic Lateral Sclerosis
What are some hallmark symptoms of an LMN (lower motor neuron) lesion?
Lower Motor Neuron Lesions
Flaccid paralysis
Muscle atrophy/wasting
Hyporeflexia
¢Paralysis from muscle atrophy
¢Wasting pronounced
¢Flaccid, hypotonic
¢DTR low or absent