Peripheral Nerves Flashcards
What are the 3 basic movements of nerves
Unfolding
Sliding
Elongation
What is unfolding
Straightening out of undulations
What is sliding
movement between the nerve and surrounding tissues at the mechanical interface
What is elongation
Tension is applied, movement occurs b/t neural elements and connective tissue layers
List the mechanisms of injury for peripheral nerve dysfunctions
Compressions - most common Ischemia Crush Injury Traction Injury/stinger Severance
Seddon vs sunderland classification
seddon is 3 levels whereas sunderland takes the 3 levels and converts it into 5 based on histology
List the 3 grades of classification for seddon
Neuropraxia
Axonotmesis
Neurotmesis
What is neuropraxia
grade 1 of seddon: transient compression injury w/minimal structural changes
what is axonotmesis
grade 2 of seddon: axon damaged, but endoneurial tube is intact & prognosis depends on regeneration of axon
what is neurotmesis
grade 3 of seddon: entire nerve is injured
What is Grade 1 Sunderland
conduction block (like neuropraxia)
What is Grade 2 Sunderland
axonal injury (like axontomesis)
What is Grade 3 Sunderland
Axon and endoneurium injjury
What is Grade 4 Sunderland
axon, endoneurium and perineurium injury
What is Grade 5 Sunderland
complete disruption of all structures
What is wallerian degeneration
nerve fibers distal to the injury degenerate
What happens following peripheral nerve injury?
Wallerian Degeneration, myelin complex disrupted, schwann cells proliferate
What are filopodia
Fine growth cones that come appear in order to anchor to the basement membrane and enter the endoneurial tubes, growing 1-2mm/day
What is the pattern of recovery of a neuron
PROX TO DISTAL
- hypersensitivity
- perception for slow vibration
- perception of moving touch
- perception of constant touch
- perception of rapid vibration
What are the signs of a recovering nerve
voluntary mm contraction
hypersensitivity
What are potential complications to nerve healing
- sprouts fail to make schwann cell contact
- blocked by scar tissue
- neuroma formation (cluster of nerve tissue from complications)
- sprouts to wrong neural tube
How can PT help with nerve recovery
Patient education of how to protect it
Movements to protect adhesions and contractures
Protective devices
What is an entrapment
nerve doesn’t move by sliding due to adherence to other tissues and elongation causing symptoms of pain
What is thoracic outlet syndrome
Entrapment of the brachial plexus and vascular tissue (b/t anterior and middle scalenes, b/t 1st rib and clavicle, or b/t pectoralis minor and rib cage)
Suprascapular nerve entrapment
a) nerve roots
b) cutaneous distribution
c) injuries from
a) C5 & C6 (some C4)
b) proximal lateral 1/3 of arm
c) trauma (fxs, dislocations, penetrating) overuse, mass lesion, iatogenic cause
what is an iatrogenic cause
caused by a visit to a Dr
Where can the suprascapular nerve become entrapped
suprascapular notch
spinoglenoid notch
compression b/t spine of scap and infraspinatus and supraspinatus mms
what are the signs and symptoms for suprascapular nerve entrapment
Usually insidous onset
dull, aching pain in posterior shldr, increased w/OH activities
atrophy of infraspinatus and supraspinatus mm
What are the 3 possible median nerve entrapments
Pronator syndrome
anterior interosseous syndrome
carpal tunnel syndrome
What are the signs and symptoms of Pronator syndrome
pain, tenderness, cramping of prox. anterior forearm mm, sensory changes
pain w/resisted pronation, tenderness to palpation, weakness of FPL, FDP and PQ, weak pinch
What is the pronator compression test
P applied for > 30 sec at edge of PT
Resisted finger flexion, prox. PIP of 3rd digit
Indicates compression at level of FDS
Why does compression occur w/pronator syndrome
The fascial impingement of the lacertus fibrosis
T or F: AIN Syndrome does not have sensory deficits
TRUE! It is a motor impairment only
What is the primary site of compression for AIN syndrome
Point of division from median nerve and near the tendinous insertion of the PT mm
What are the s/s for AIN
deep forearm pain that does not resolve w/rest
+ pinch test (3-jaw pinch)
Weakness of FPL and half FDP
+ EMG
PTS vs AIN
a) sensory changes
b) pronator compression test
a) Positive sensory changes PTS not AIN
b) positive pronator compression test for PTS not AIN
What are some causes of Carpal Tunnel Syndrome (CTS)
Anything that alters space of carpal tunnel
Fx, overuse, swelling, RA, pregnancy, etc
S/S of CTS
Tingling and numbness in the thumb, index, and middle fingers
aching in thumb, writs, and digits of the hand
burning pain at night
dec. sensation to temp and touch
atrophy of thenar mm
+ Phalens test (compress CT)
+ Tinel’s test (tapping)
Treatments for CTS
- Conservative: splints w/wrist in 0-20 deg /
- avoid contributing activities
- NSAIDs
- Steroid injections
- promote tendon gliding
- Sx
What is open carpal tunnel surgery
Cut open the flexor retinaculum to open space for bone to relieve nerve tension
What is endoscopic carpal tunnel surgery
shorter recovery time with less of an incision for healing
What are the 4 locations for ulnar nerve entrapments
Cubital tunnel: around the tunel or posterior to medial epicondyle
Flexor carpi ulnaris mm belly
guyon’s canal
What is the hx for cubital tunnel syndrome
prolonged flexion of the elbow, common in throwing athletes, manual laboreres, and musicians
What are the s/s of cubital tunnel syndrome
Pain in prox. ulnar aspect of forearm Tingling in 5th and 4th digit Clumsiness of hand Hyperesthesia or numbness dull ache after activity or at rest radiation of pain atrophy dec. sensation sudomotor changes
What are the provocation tests for Cubital tunnel syndrome
+ tinels at elbow
+ fromnets sign (unable to do key grip and abduct thumb)
+ elbow flexion test
+ NCS, + EMG
What is ulnar nerve transposition
Sx to move the nerve from the groove to the anterior aspect, under the flexor/pronator mm mass (submuscular) or inside the mm (intramuscular)
What are the s/s of guyon’s canal syndrome
decreased palmar sensation
intrinsic mm weakness, + EMG
What are the two spots for compression of the radial nerve
Radial tunnel
Posterior interosseous nerve (comp of PIN at arcade of froshe as it enters the prox border of the supinator mm)
PIN S/S
Aching pain along extensor surface of forearm and hand pain at elbow NO SENSORY PROB Pain w/deep palpation distal to lat. Weakness of finger extensors
What is Wartenberg’s syndrome
Superficial radial nerve entrapment caused by direct trauma to forearm, blow to hand, tight cast, or tight watchband or bracelet
S/S of superficial radial nerve entrapment
local tenderness at wrist
pain in forearm
numbness and paresthesia of dorsum of hand
sensory loss to rad distribution of hand
What is complex regional pain syndrome (CRPS)
Linked to fx or sprains of extremities w/pain and dysfunction out of proportion to injury
What is Type III CRPS
Combo of Type I and Type II w/both sensory and motor deficits
S/S Type I CRPS
Pain and swelling in extremity, stiffness and color changes
Edema, functional deficits
* Mostly sensory involvements
S/S Type II CRPS
More regionally confined
Intermittent variable edema
T changes
* Motor dysfunction
What are the 3 stages in CRPS
Warm (acute stage up to 6 mo w/increase in perfusion)
Cold (low skin temp w/low perfusion values)
Intermediate (high and low depending)
What are the 4 diagnostic criteria for the international association for the study of pain for CRPS
- sensory (hyperesthesia, hyperalgesia and allodynia)
- vasomotor (T assym, skin color change/assym)
- Sudomotor/edema (edema and or sweating changes/asymm)
- Motor/trophic (motor dysfun/trophic changes)
What is allodynia
Increase in pain from a stimulus that normally does not cause pain
How many of the IASP criteria must you have to have CRPS
1 sign in >=2 categories and at least one symptom in 3 or 4 cat.
What are the behaviour symptoms of CRPS
emotions
stress and anxiety
Temperature
What are the sciatic nerve entrapments
Deep gluteal syndrome Piriformis syndrome (most common)
What 3 specific conditions contribute to piriformis syndrome
- MF pain refered from trigger points in piriformis
- Nerve and vascular entrap by piriformis at greater sciatic foramen
- dysfunctions of the SI joint
S/S of piriformis syndrome
Buttock pain radiating down post. aspect of thigh and calf
MF weakness on resisted abd
Paresthesias and dysthesia in nn distribution
Increase symptoms in FABER position
SI dysfuction
Loss of hip IR, stands in ER of legs
What is meralgia paresthetica
Femoral nerve entrapment that is uncommon and pure sensory
S/S of meralgia paresthetica (femoral nerve entrapment)
Pain along course of nerve Pain along anterolat. aspect of thigh Hypersensitivity Burning tingling relief w/rest Inc. pain w/passive hip /, dec sensation, pain reproduced w/pressure on nerve
What is the most common nerve entrapment syndrom ein the LE
Tarsal Tunnel syndrome (TTS)
what is tarsal tunnel syndrome (TTS)
entrap of the posterior tibial nerve or one of its branches w/in the tarsal tunnel
S/S of TTS
Burning dysesthesia or anesthesias in plantar/medial aspect of foot
WB increases symptoms
Rearfoot pronation w/excessive eversion of the heel during stance
What is mortons neuroma S/S
electrical shock or burning at ball of foot Second toe and spreads out Intermittent pain increases w/WB and at night Tender to palpate Compress MT heads to reproduce symptoms
What is intercostal neuralgia
Shingles caused by infection from Herpes zoster -> nerve compression by disk protrusion
S/S of shingles
headache, fever, malaise burning pain following nerve path unchanged by med or rest numbness or itch at a particular place rash or blisters following path of the nerve
What is morton’s neuroma
Overgrowth of the nerve itself between the second and third toe on the foot
What is complex regional pain syndrome (CRPS)
Pain and dysfunction out of proportion to an injury, typically linked to fractures or sprains of the extremities with sympathetic NS involvement
What is CRPS Type I
Pain disproportionate to the initiating event with sensory involvement
What is Type II CRPS
More nerve involvement than CRPS Type I –> causalgia; Mostly motor involvement
