Compressive Neuropathies (s. Entrapment Neuropathies, Tunnel
FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.
-
Upload
clarissa-claudia-ritch -
Category
Documents
-
view
215 -
download
0
Transcript of FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.
![Page 1: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/1.jpg)
FOCAL NEUROPATHIES
William McKinley MD
Associate Professor PM&R
Virginia Commonwealth University
![Page 2: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/2.jpg)
ETIOLOGY
Compression (any external pressure)Entrapment (anatomical compression site)Repetitive trauma/overuseDirect trauma (missile, laceration)ischemiaStretch
![Page 3: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/3.jpg)
PATHOPHYSIOLOGY:Compression vs Ischemia
Compression vs Ischemia Focal demylination vs axonal injury
Mechanical compression 30 mmHg - decreased blood flow 30-60 mmHg - block of axoplasmic transport >60 mmHg - absent blood flow
Ischemia 15-45 min causes dec conduction (neuropraxia)
• less than 60 min - reversible greater than 8 hours - not reversible
![Page 4: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/4.jpg)
MECHANICAL COMPRESSION
Pressure will lead to: paranodal demyelination
• conduction abnormalities (slowing, conduction block) Axonal injury - wallerian degeneration
Pressure selectively affects• large Type A fibers (motor, LT, vib) > small Type C
(pain/temp)• Peripheral (sensory) >central (motor) fibers
![Page 5: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/5.jpg)
Nerve Recovery after injury
Peripheral N’s (unlike CNS) can regenerate.Remyelination - takes up to 3 months
however myelin is thin and internodes short (slow!)
Axonal Reinnervation Collateral Sprouts from adjacent intact axons Growth cones (NGF) from axon stump - span “gap” &
travel via endo tube 1-3 mm/d (1 inch/month)• Abberant re-innervation & neuroma• Muscle atrophy irreversible begins at one year• Sensory receptors survive for many years
![Page 6: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/6.jpg)
CLASSIFICATION OF NERVE INJURY
Seddan’s Classification Neuropraxia - local cond. “block” with
demyelination (reversible) Axonotmesis - axonal injury w/wallarian
degeneration (endoneurium intact, re-innervation possible)
Neurotmesis - complete disruption of axon and endoneurial sheath (no innervation possible)
![Page 7: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/7.jpg)
PM&R approach to the patient with focal neuropathy
HistoryPE?Electrodiagnosis?additional tests (rad, U/S, vasc studies)
![Page 8: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/8.jpg)
PHYSICAL EXAM
Inspection, palpation, Motor/Sensory, DTR, provocative tests Tinels, phalens, pinch, froments, spurlings,
SLR
Know nerve anatomy & innervations!Know common sites of entrapment!
![Page 9: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/9.jpg)
HISTORY
Timing: acute vs. insidious, ? Inciting event, what…better/worse
Occupation & Handedness: association with repetitive trauma
PMH: related to diseases? (DM, CTD) Location of: paresthesias (not always
anatomically distributed), numbness, Weakness
![Page 10: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/10.jpg)
DIFFERENTIAL dx
Peripheral neuropathy (DM, ETOH, uremia; drugs, toxins)
PlexopathyRadiculopathy“Double Crush” or “vulnerable nerve
syndrome (ie: radic + focal neuropathy)Spinal Cord InjuryMyofacial/referred pain
![Page 11: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/11.jpg)
Electrodiagnosis (Edx):
Can assist with: localization of injury
extent of injury (mild, moderate, severe)
assessment for underlying dz (DM, hypothy) and/or concomitant issues (“double crush”)
![Page 12: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/12.jpg)
Electrodiagnosis = NCS + NEE
Sensory (SNAP) NCSMotor (CMAP) NCSProximal (“late”) NCS: (H Reflex, F Wave)
limited use in focal neuropathy
Needle EMG (NEE)
![Page 13: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/13.jpg)
NCS findings with Focal Demyelination
Loss of conduction prolonged latency, slow CV
Abnormal proximal (to injury) stim response - (dec amplitude) compared with distal
conduction block if normal distal (to injury) amplitude = no axonal
degeneration
![Page 14: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/14.jpg)
NCS findings with Axonal loss
NCS amplitude (measures # of fibers) loss• Motor and sensory amplitudes can help predict degree of axon loss
(comparison: with normal, proximal vs distal & side to side)
Distal wallerian degeneration• depends on distance (injury site to muscle)
Preservation of sensory NCS for up to 10 days
preservation of motor NCS for up to 7 days (NMJ)
![Page 15: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/15.jpg)
NEEDLE EMG (NEE)
Severe compression will cause axonal injury and lead to signs of muscle fiber injury (positive sharp waves, fibrillations). Needle EMG is helpful 3- 4 weeks post injury
Nerve fiber recruitment is assessed. “Pattern” of involvement will help localize!You can also monitor “progression or
recovery” (reinnervation) with needle EMG.
![Page 16: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/16.jpg)
![Page 17: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/17.jpg)
Conduction Block CB & Axonal loss
![Page 18: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/18.jpg)
Case Example: AXONAL loss vs DEMYELINATION
Ulnar Motor NCS to ADQ muscle Rt Amplitude = 10 MV (BE), 10 MV (AE) Lt Amplitude = 5 MV (BE), 2.5MV (AE)
Thus: Abnormal Lt ulnar motor with: 50% Axonal loss, 5 vs 10 (BE) - Lt vs Rt 50% Conduction block, 2.5 vs 5 -( AE vs BE)
LT
![Page 19: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/19.jpg)
PROXIMAL NERVE ENTRAPMENT SYNDROMES
NERVE LOCATION SYNDROME MUSCLE INVOLVED
Facial Interosseus Bell’s palsy Facial, Frontalis
Sp Accessory Neck Tumor, Surg Upper Trapezius
Long Thoracic Supraclavic Trauma, Stretch Serratus Anterior
![Page 20: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/20.jpg)
PROXIMAL NERVE ENTRAPMENT SYNDROMES
NERVE LOCATION SYNDROME MUSCLE INVOLVED
Suprascapular Suprascp Notch Backpack palsy Supra, infraspinatus
Musculo- Pierces Corac- Overuse Biceps, Brachials
cutaneous brachial coracobr.
Axillary Axilla Hum.fx Deltoid teres min
![Page 21: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/21.jpg)
![Page 22: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/22.jpg)
![Page 23: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/23.jpg)
MEDIAN NERVE ENTRAPMENT SYNDROMES
NERVE LOCATION SYNDROME MUSCLE INVOLVED
Median Lig. Struthers LOS Pro Teres Involved
Median Pro Teres M Pronator Pro Teres. Spared
Teres Syndrome
Median A.I.N Anterior FPL, FDP (I II),
Int Syn PQ
Median Carpal Tunnel Carpal Tunnel Intrinsic hand
Syndrome
![Page 24: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/24.jpg)
Median Neuropathy
Carpal Tunnel Syndrome- most common entrapment syndrome CT encloses 9 tendons and median nerve under
transverse carpal lig. CTS site is 3-4 cms distal to wrist crease CTS bilateral in 55%
![Page 25: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/25.jpg)
CTS: Clinical exam
Symptoms: Numbness to lateral 3 digits, weakness in flexing fingers or abducting thumb, nighttime exacerbation, trophic changes.
ddx: C6-7 radiculopathy, or polyneuropathySigns: Phalens, “reverse” Phalens, Tinels,
“flick” sign
![Page 26: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/26.jpg)
![Page 27: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/27.jpg)
Median Neuropathy: Fun Facts
“Hand of benedictine” - Median Neurop seen w/ finger flexion “Double Crush” Syndrome (decreased axoplasmic flow predisposes
for CTS) cervical radiculopathy and CTS Martin-Gruber anastamosis (median to ulnar crossover of ulnar fibers).
Seen 15-30%, bilat in 70% , most common M. innervated is FDI
larger amp with stim elbow (vs. wrist) initial positive deflection in CTS increased NCV in CTS
Canieu Riche Anomaly (Anastomosis between the recurrent branch of the median N. and the deep br. of the ulnar N.) “Ulnar hand “ to FPB and opponens
![Page 28: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/28.jpg)
![Page 29: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/29.jpg)
Ulnar NERVE ENTRAPMENT SYNDROMES
NERVE LOCATION SYNDROME MUSCLE INVOLVED
Lower trunkThoracic outlet TOS All Ulnar M’s + median motor
Ulnar Ulnar Groove Tardy Ulnar +/- FCU
Palsy
Ulnar Betw Heads of Cubital Tunnel Spares FCU
FCU Syn
Ulnar Pisaform/Hamate Guyon’s Canal Ulnar Intrins
Ulnar Palm “Walker, Bike” Motor Only (FDI, Add Poll)
![Page 30: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/30.jpg)
![Page 31: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/31.jpg)
Ulnar Neuropathy at elbow
2nd most common entrapment syn Ulnar N superficial in UG & Cubital tunnel Ulnar Groove (UG - behind med. epic) - Most
common site • due to pressure (leaning on elbow), repetitive
motion (F/E), subluxation (18%, prior trauma (“Tardy Ulnar Palsy”), valgus deformity
Cubital tunnel (beneath aponeurosis joining 2 heads of FCU) is 2 cm distal to UG.
![Page 32: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/32.jpg)
Ulnar Neuropathy: clinical exam
Ddx: C8-T1 radiculopathy, lower plexus lesion (TOS), CTS
Froment’s Sign, tinel, Horners (T-1), Ulnar Claw hand - seen w finger extension
![Page 33: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/33.jpg)
Edx of Ulnar neuropathy @elbow
assess NCV across elbow “tricky” Edx findings ulnar N is “lax” in extension, and will tighten
w/flexion, also can sublux perform NCS with Elbox flexion 70-90 deg consider SSIS (“inching”) testing across elbow
(20% drop in amp is signif) NEE - FDI & forearm m’s
![Page 34: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/34.jpg)
Ulnar Nerve: Fun Facts
Guyon’s Canal - etiol: ganglion cyst 30%, 25% recurrent trauma, 23% acute trauma
Shea-McClean Classification
• proximal canal: Motor and sensory deficits (30%)
• distal canal : Deep motor branch only (50%)
• superficial sensory branch to 4th and 5th digits (20%)
Dorsal ulnar Cutaneous N (DUC) - given off 8-10 cm proximal to wrist (does not go thru Guyons canal)
![Page 35: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/35.jpg)
![Page 36: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/36.jpg)
![Page 37: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/37.jpg)
RADIAL NERVE ENTRAPMENT SYNDROMES
NERVE LOCATION SYNDROME MUSCLE INVOLVED
Radial Axilla Crutch Palsy Includes Triceps
Radial Spiral Groove Saturday Night Spares Triceps, weak Palsy/Fx ECR, sup, BR
Posterior Acrade of Posterior ECU, but spares
Inteross Frohse Inteross N. sup, ECR, BR
(Radial) (supinator) Synd (PIN)
SupRadial Wrist “Chiralgia” Sensory only
![Page 38: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/38.jpg)
Radial Nerve: Fun Facts
Good prognosis in radial nerve injuriesLead toxicity commonly affects radial nerveTest BR muscle with forearm in “neutral” positionSuperficial Radial N (sensory) given off proximal to
supinator mPIN (Post. Interosseous N.) traverses supinator thru
Arcade of FrosheExam may reveal apperent weakness of interossei
(ulnar) or thumb abduction (median)
![Page 39: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/39.jpg)
LE NERVE ENTRAPMENT SYNDROMES
NERVE LOCATION SYNDROME MUSCLE INVOLVED
Illioinguinal nerve, Genitofemoral nerve, Lateral femoral cutaneous nerve
(meralgia paresthetica), sural nerve, all rarely subject to isolated lesioins
Femoral Psoas/Retroperitoneal Hip Flex/Knee Ext
Femoral Inguinal Knee ext
Saphenous Hunter’s Sensory only
Canal
Obturator Pelvis Adductors
![Page 40: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/40.jpg)
LE NERVE ENTRAPMENT SYNDROMES
NERVE LOCATION SYNDROME MUSCLE INVOLVED
Superior Gluteal Hip Injections Glut min/med
Inferior Gluteal Injections Glut max
Sciatic Under Pyriform Pyriform Short head bicep
Syndrome
![Page 41: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/41.jpg)
SCIATIC NERVE
Course: thru greater Sciatic Foramen, beneath pyriformus M.
20% pass “thru” pyriformis (esp. peroneal division)
Peroneal division is most commonly involved (larger, fixed at fibula)
Etiology: Pelvic, hip or SI joint fractures, stretch injury, injections (SN), vaginal delivery (OBT), retropetroneal hematoma
Stim.site between ischeal tuberosity and gr. trochanter
![Page 42: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/42.jpg)
![Page 43: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/43.jpg)
PERONEAL NERVE ENTRAPMENT SYNDROMES
NERVE LOCATION SYNDROME MUSCLE INVOLVED
Common Head of Fibula Dorsiflex,
Peroneal Evertors
Deep Peroneal Distal to Fib Boot Dorsiflex, Dorsal
Web Sens
Deep Per “Ant” tarsal E.D. Brevis
Tunnel
![Page 44: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/44.jpg)
Peroneal Neuropathy
Ddx: L5 radiculopathy check ankle inversion & hamstring DTR (both abnl in
L5 radic), tib post, glu med m’s
Etiology : leg crossing, weight loss, depression, casts, ankle injuries (stretch)
SHB (short head of Biceps Femoris) - thigh pierces PL m (fibular tunnel)
then divides into sup/deep peroneal
Accessory Peroneal (20%) - lat malleolus
![Page 45: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/45.jpg)
![Page 46: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/46.jpg)
TIBIAL NERVE ENTRAPMENT SYNDROMES
NERVE LOCATION SYNDROME MUSCLE INVOLVED
Tibial Under Flexor Tarsal Tunnel Intrinscs
Compart
Plantar 3/4 Toe Morton’s Sens/Pain
(Digital) Neuroma
![Page 47: FOCAL NEUROPATHIES William McKinley MD Associate Professor PM&R Virginia Commonwealth University.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649c8a5503460f94943f99/html5/thumbnails/47.jpg)
“failure is not an option”!
IOHCYLTTLGTG/MDAF