Download Free Medical Peripheral nerve disorders-A practical overview PowerPoint Presentation

Peripheral nerve disorders-A practical overview PowerPoint Presentation

DOWNLOAD MEDICAL POWERPOINT PRESENTATION

About This Presentation

Description : Check out this medical presentation on Orthopaedics, which is titled "Peripheral nerve disorders: A practical overview", to know about peripheral nerve disorders.

Tags : Orthopaedics, Peripheral nerve disorders

Published on : Aug 10, 2021 | Views : 2511 | Downloads : 7

Shareable Url :

Embed Code :

Comment

Transcript

Slide 1-

Peripheral nerve disorders: A practical overview Praveen Dayalu, MD Clinical Associate Professor Department of Neurology University of Michigan
Slide 2-

What is the Peripheral Nervous System? CNS is confined to brain and spinal cord PNS includes (in anatomical order) Anterior horn cell (located within spinal cord) Spinal nerve roots (radicles) Plexi (brachial and lumbosacral) Named peripheral nerves (e.g. median, peroneal) Tiny nerve endings (sensory fibers and tiny branches of lower motor axons at the neuromuscular junction) Neuromuscular junction and muscle 2
Slide 3-

Neuromuscular junction and muscle Ulnar nerve Brachial plexus C8 spinal nerve root Anterior horn cells (LMN) The PNS (Emphasizing Motor Structures)
Slide 4-

4 Myelin (Schwann cells) Many peripheral axons are myelinated
Slide 5-

Symptoms of PNS Disease Single focal lesions: weakness/numbness/ pain in one limb, often defined to one part of the limb Multiple or diffuse lesions: weakness/ numbness/pain in more than one limb, usually bilateral and distal 5
Slide 6-

Signs of PNS Disease Lower motor neuron signs (atrophy, fasciculations) Hyporeflexia or areflexia Patch of sensory loss, or stocking-glove sensory loss Not UMN signs (spasticity, hyperreflexia, upgoing toe) or “brain” signs (impaired consciousness, cognition, or language) 6
Slide 7-

Reflexes… repeated Hyperreflexia and spasticity occur with upper motor neuron lesions (CNS) Hyporeflexia, fasciculations, atrophy with lower motor neuron lesions (PNS) 7
Slide 8-

Workup Serologies, especially for treatable causes EMG helps localize and characterize lesions of PNS Imaging for some focal lesions, or to exclude CNS mimics (such as cord lesion or stroke) CSF analysis in demyelinating neuropathies, or polyradiculopathy Nerve biopsy 8
Slide 9-

Anterior Horn Cell 9
Slide 10-

Amyotrophic lateral sclerosis Anterior horn cells (lower motor neurons) and upper motor neurons degenerate Mix of UMN and LMN signs/symptoms Weakness, spasticity, multifocal muscle atrophy No sensory loss from ALS! Loss of speech, swallow, respiration Death in 2-5 years 10
Slide 11-

Neuromuscular junction and muscle Ulnar nerve Brachial plexus C8 spinal nerve root Radiculopathy
Slide 12-

Spinal Nerve Root Disorders Most common: monoradiculopathy (cervical or lumbosacral) Radiating pain, +/- weakness, +/- sensory loss. Reduced reflex for that root level Commonest causes: disk herniation, minor trauma, degenerative change Usually self-limited Image if severe, worsening, or concern for cancer, infection 12
Slide 13-

13
Slide 14-

Neuromuscular junction and muscle Ulnar nerve Brachial plexus C8 spinal nerve root Plexopathy
Slide 15-

Plexopathy PNS syndrome in one limb not explained by a single spinal root, or by a single “named” peripheral nerve Causes: trauma or stretch, compression by tumor or hematoma, radiation, diabetic EMG confirms plexopathy Image if compressive lesion suspected 15
Slide 16-

Brachial Plexus behind clavicle, in upper thorax 16
Slide 17-

Lumbosacral Plexus: Pelvic, Retroperitoneal 17
Slide 18-

Neuromuscular junction and muscle Ulnar nerve Brachial plexus C8 spinal nerve root Mononeuropathy
Slide 19-

Mononeuropathy Weakness, numbness, pain, paresthesias confined to the distribution of UE: median nerve, radial n., ulnar n. LE: femoral n., sciatic n., peroneal n. Most common causes: entrapment, trauma, prolonged limb immobility (e.g., surgery) 19
Slide 20-

Important Mononeuropathies Median mononeuropathy at the wrist (carpal tunnel syndrome) Ulnar mononeuropathy at the elbow (cubital tunnel syndrome) Radial mononeuropathy (“Saturday night palsy”) wrist and finger drop Peroneal mononeuropathy (e.g., from leg crossing) one cause of footdrop 20
Slide 21-

Median n. Ulnar n. Peroneal n. Named peripheral nerves have well-defined sensory territories (and muscle targets) 21
Slide 22-

Peripheral Polyneuropathy
Slide 23-

23
Slide 24-

“Peripheral Neuropathy” Distal symmetric polyneuropathy Affects longest sensory/ motor/ autonomic nerves Nerves are “dying back” Length dependent (“stocking glove”) Symmetric loss of pin/ temp / vibration/ proprioception; distal reflex loss Usually chronic. Many possible causes! 24
Slide 25-

Peripheral polyneuropathy symptoms Initially, feet numb with paresthesia/ pain Symptoms ascend:  legs fingertips Distal weakness (feet, or fingers/grip), atrophy, Severe sensory loss can cause “steppage gait”, “sensory ataxia”, imbalance, falls Feet prone to injuries, ulcers, deformation (e.g., “Charcot foot”) Autonomic: orthostasis, bladder and erectile dysfunction 25
Slide 26-

Causes of peripheral polyneuropathy Usually toxic or metabolic #1 cause: diabetes & impaired glucose tolerance B12 Hematologic (e.g., multiple myeloma) or other immunoglobulin disorders (check SPEP) Drugs: Li, chemotherapy Alcoholic neuropathy Liver or kidney disease HIV and neurosyphilis Inflammatory causes: connective tissue disease 26
Slide 27-

Workup for peripheral neuropathy? For typical distal symmetric sensory > motor neuropathy: glucose / a1c, B12, SPEP with ifix Need EMG and more if rapid or severe, prominent weakness, asymmetry, young patient
Slide 28-

AIDP = Acute Inflammatory Demyelinating Polyneuropathy Develops over ~2 weeks Follows viral infection or vaccination Weakness/ numbness/ paresthesia start in legs and ascend; reflexes lost early Intubate if severe weakness Autonomic instability, arrhythmia Rx: plasma exchange & IVIG Most have good long-term recovery 28
Slide 29-

Myopathy = muscle disease “Can’t raise arms up” “Tough to comb my hair” “Hard to get out of a chair” “Can’t climb stairs” 29
Slide 30-

Clues to a Myopathy Usually cause symmetric proximal limb weakness (upper/lower) Other possible sx: muscle pain, tenderness, atrophy; fatigue; change in urine color Extensive list of causes: TSH, CK, and med review are a good place to start 30
Slide 31-

Time for review questions?
Slide 32-

Over 3 days, a 42 y.o. RN rapidly weakens in all four limbs. She says “I think I have Guillain-Barré!” Which is the most urgent first step? EMG Spinal cord imaging Lumbar puncture Brain imaging 32
Slide 33-

A 61 y/o woman wakes up with a weak right arm. Zero strength in finger extensors, wrist extensors, and trace elbow extension. Flexion muscles are 5/5. Which is the most likely diagnosis? Left frontal stroke affecting motor cortex Carpal tunnel syndrome Right radial mononeuropathy Peripheral polyneuropathy 33
Slide 34-

Decreased reflexes are seen in all of the following except: AIDP Peripheral polyneuropathy Carcinomatous polyradiculopathy Alcoholic neuropathy Steroid myopathy 34
Slide 35-

Weakness and sensory loss in the left hand can be caused by all of the following except: Right hemisphere stroke Lung cancer invading brachial plexus Median mononeuropathy Amyotrophic lateral sclerosis Cervical herniated disk
Slide 36-

Which is the commonest symptom of radiculopathy in the general public? Weakness Radiating pain down a limb A patch of distinct sensory loss Bladder incontinence 36