Peripheral Nerve + Neuromuscular Disorders Flashcards
Diabetic neuropathy Radiculopathies Mononeuropathy Myasthenia gravis Neurofibromatosis Peripheral nerve injuries/palsies/lesions
What is diabetic neuropathy?
A type of nerve damage caused by long-term high blood sugar levels in diabetes, affecting sensory, motor, and autonomic nerves.
True or False: Diabetic neuropathy affects only the peripheral nerves.
False. It can affect sensory, motor, and autonomic nerves.
Name the most common form of diabetic neuropathy
Distal symmetric polyneuropathy (DSPN).
List the major risk factors for diabetic neuropathy.
Long duration of diabetes.
Poor glycemic control.
Hypertension.
Obesity.
Smoking.
True or False: Good glycemic control can reduce the risk of diabetic neuropathy.
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What are the four main types of diabetic neuropathy?
Peripheral neuropathy.
Autonomic neuropathy.
Focal neuropathy.
Proximal neuropathy.
Match the type of diabetic neuropathy with the primary symptom:
Peripheral neuropathy
Autonomic neuropathy
Focal neuropathy
Proximal neuropathy
Peripheral neuropathy: Pain and numbness in extremities.
Autonomic neuropathy: GI, cardiovascular, or bladder dysfunction.
Focal neuropathy: Sudden, localized nerve damage (e.g., cranial nerve palsy).
Proximal neuropathy: Weakness and wasting in the hip or thigh muscles.
List common symptoms of peripheral neuropathy in diabetes.
Numbness and tingling in hands and feet.
Burning or shooting pain.
Loss of coordination or balance.
Muscle weakness.
True or False: Autonomic neuropathy can cause gastroparesis and orthostatic hypotension.
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What are the key pathological mechanisms behind diabetic neuropathy?
Chronic hyperglycemia leading to oxidative stress.
Accumulation of advanced glycation end products (AGEs).
Microvascular damage reducing blood supply to nerves.
Direct metabolic injury to nerve cells.
What clinical tests are used to diagnose diabetic neuropathy?
Monofilament test for loss of sensation.
Vibration perception threshold (tuning fork).
Ankle reflexes for motor involvement.
Nerve conduction studies.
True or False: Diabetic neuropathy is primarily a clinical diagnosis based on history and physical exam
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What are the main goals of managing diabetic neuropathy?
Control blood sugar levels.
Relieve symptoms (e.g., pain).
Prevent complications (e.g., foot ulcers).
Name first-line pharmacological treatments for diabetic neuropathy pain.
Duloxetine.
Pregabalin.
Gabapentin.
True or False: Tricyclic antidepressants are used off-label for neuropathic pain.
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What lifestyle changes are recommended for managing diabetic neuropathy?
Regular exercise.
Smoking cessation.
Weight management.
What complications can arise from diabetic neuropathy?
Foot ulcers and infections.
Charcot foot.
Autonomic dysfunction (e.g., arrhythmias, gastroparesis).
Loss of limb due to severe infections or gangrene.
True or False: Diabetic neuropathy can lead to silent myocardial infarctions.
True, due to autonomic involvement.
What is radiculopathy?
A condition caused by compression or irritation of a nerve root, leading to pain, weakness, or sensory changes in the corresponding dermatome.
Fill in the blank: The most common causes of radiculopathy are __________ and __________.
Degenerative disc disease; herniated discs.
Name the most common cervical and lumbar radiculopathies.
Cervical: C6 and C7.
Lumbar: L5 and S1.
True/False: L5 radiculopathy often presents with reduced Achilles tendon reflexes.
False (S1 radiculopathy affects the Achilles reflex).
What imaging modality is first-line for diagnosing radiculopathy?
MRI of the spine.
What is the primary cause of radiculopathy?
Compression or irritation of nerve roots in the spinal column, often due to a herniated disc, spinal stenosis, or osteophytes.
Name the most common radiculopathy locations.
Cervical and lumbar spine.
What is the typical clinical presentation of lumbar radiculopathy?
Lower back pain radiating down the leg, typically in a dermatomal pattern, often with weakness or altered sensation.
How is radiculopathy diagnosed?
Clinical examination, MRI for imaging, and sometimes nerve conduction studies or EMG for functional assessment.
What conservative management options are recommended for radiculopathy?
Analgesia (NSAIDs), physiotherapy, and activity modification.
T/F1: Spinal stenosis is the most common cause of cervical radiculopathy in younger patients.
False. It is more common in older patients.
T/F2: The straight leg raise test is used to assess for lumbar radiculopathy.
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The nerve roots involved in a C5 radiculopathy are responsible for ____________ and elbow flexion strength.
Shoulder abduction.
The most common nerve root affected in lumbar radiculopathy is _______.
L5
A 50-year-old presents with neck pain radiating to the right arm, weakness in elbow flexion, and sensory loss over the lateral forearm. Which nerve root is likely affected?
C6 radiculopathy.
Define radiculopathy.
Radiculopathy refers to a condition caused by the compression, inflammation, or injury of a nerve root, often presenting with pain, weakness, numbness, or tingling along the nerve’s distribution.
What are common causes of radiculopathy?
Herniated disc – nerve root compression by displaced disc material.
Degenerative changes – osteophyte formation or ligament thickening.
Trauma – direct injury to the spine or nerve roots.
Infection or tumor – causing inflammation or space-occupying lesions.
Congenital conditions – such as spinal stenosis.
What are typical symptoms of radiculopathy?
Pain: Radiates along the affected nerve (sharp, shooting).
Sensory changes: Numbness, tingling (paresthesia).
Motor changes: Weakness, difficulty in movement.
Reflex changes: Reduced or absent deep tendon reflexes in affected areas.
What investigations are used to diagnose radiculopathy?
MRI – Gold standard to identify disc herniation, compression, or structural changes.
X-ray – Evaluates spinal alignment and bony changes.
Electromyography (EMG): Assesses nerve function and identifies specific nerve root involvement.
How is radiculopathy managed?
Conservative: Physical therapy, pain management with NSAIDs, muscle relaxants.
Interventional: Epidural steroid injections for persistent symptoms.
Surgical: Decompression (e.g., laminectomy) in severe or refractory cases.
What are red flag symptoms in radiculopathy?
Saddle anesthesia, bowel/bladder incontinence, or progressive motor weakness suggest cauda equina syndrome and require urgent intervention.
What is the slump test?
A clinical test for nerve root irritation, where symptoms are reproduced by flexing the spine, extending the knee, and dorsiflexing the ankle.
Which nerve roots are commonly affected in lumbar radiculopathy?
L5 and S1 are the most frequently involved.
Define mononeuropathy.
Mononeuropathy refers to a condition where a single peripheral nerve is damaged, leading to localized symptoms such as motor weakness, sensory loss, or both.
Name an example of mononeuropathy.
Examples include carpal tunnel syndrome (median nerve), ulnar neuropathy, and meralgia paraesthetica (lateral femoral cutaneous nerve).
List causes of mononeuropathy
Causes include trauma, repetitive strain, compression (e.g., tight clothing), systemic diseases (e.g., diabetes), and infections.
Compression of the ________ nerve can cause meralgia paraesthetica.
Lateral femoral cutaneous.
What are the symptoms of mononeuropathy?
Symptoms may include pain, burning, tingling, numbness, or weakness in the affected nerve distribution.
True/False: Mononeuropathies always present with motor symptoms.
False. Some, like meralgia paraesthetica, affect only sensory nerves.
Describe the sensory symptoms in meralgia paraesthetica.
Burning, numbness, pins and needles, or cold sensations localized to the outer thigh.
How is mononeuropathy diagnosed?
Diagnosis is based on history, clinical examination, and nerve conduction studies. Imaging may be used to rule out compressive lesions.
Outline the conservative management for mononeuropathy.
Rest, weight loss, physiotherapy, and avoiding compression (e.g., loosening tight clothing).
_______ and _______ are first-line analgesics in managing pain associated with mononeuropathy.
Paracetamol; NSAIDs.
What surgical options are available for mononeuropathy?
Decompression, tran
True/False: All mononeuropathies require surgical intervention.
False. Many can be managed conservatively.
What nerve is affected in carpal tunnel syndrome?
The median nerve.
Ulnar neuropathy commonly occurs due to compression at the ________.
Elbow.
Define Myasthenia Gravis.
Myasthenia Gravis is an autoimmune disorder where antibodies attack acetylcholine receptors at the neuromuscular junction, causing muscle weakness and fatigue
What causes Myasthenia Gravis?
Myasthenia Gravis is caused by autoantibodies against acetylcholine receptors, leading to impaired neuromuscular transmission.
True/False: Myasthenia Gravis is primarily a hereditary condition.
False. It is an autoimmune condition.
List risk factors for Myasthenia Gravis.
Female gender (more common in women), age (commonly affects young women and older men), thymic abnormalities, and other autoimmune conditions.
What are the key clinical features of Myasthenia Gravis?
Symptoms include muscle weakness that worsens with activity and improves with rest, ptosis (drooping eyelids), diplopia (double vision), dysphagia, and difficulty with facial expressions.
Ptosis and diplopia are hallmark symptoms of ________.
Myasthenia Gravis.
What would you expect to find on examination in a patient with Myasthenia Gravis?
Ptosis, weakness in the ocular muscles, and generalised muscle weakness that worsens with repeated movements (e.g., eyelid fluttering).
True/False: Muscle strength improves with repeated testing in Myasthenia Gravis.
False. Muscle strength worsens with repeated testing.
What investigations can be used to diagnose Myasthenia Gravis?
Key tests include serum anti-acetylcholine receptor antibodies, the edrophonium test (Tensilon test), and electromyography (EMG).
The presence of anti-______ antibodies is strongly indicative of Myasthenia Gravis.
Acetylcholine.
What are the main treatments for Myasthenia Gravis?
First-line treatments include acetylcholinesterase inhibitors (e.g., pyridostigmine), corticosteroids, and immunosuppressants (e.g., azathioprine).
True/False: Surgery (thymectomy) is a potential treatment for Myasthenia Gravis.
True. Thymectomy is considered in some cases, especially in young patients.
What are the potential complications of Myasthenia Gravis?
Respiratory failure, myasthenic crisis (severe weakness affecting respiratory muscles), and thymoma.
A ________ is a common complication in Myasthenia Gravis, particularly in patients with thymic involvement.
Thymoma.
What is the typical prognosis for Myasthenia Gravis?
With appropriate treatment, most patients can lead a normal or near-normal life. However, some patients may experience fluctuations in disease severity.
What is a Myasthenic crisis?
Myasthenic crisis occurs when severe muscle weakness affects respiratory muscles, leading to respiratory failure. It requires immediate medical attention.
What is Neurofibromatosis?
Neurofibromatosis is a genetic disorder that causes tumors to form on nerve tissue, resulting in skin changes and bone deformities. There are two types: Neurofibromatosis type 1 (NF1) and type 2 (NF2).
What is the genetic cause of Neurofibromatosis type 1 (NF1)?
NF1 is caused by a mutation in the NF1 gene located on chromosome 17, which encodes neurofibromin, a tumor suppressor.
How is Neurofibromatosis type 2 (NF2) inherited?
NF2 is inherited in an autosomal dominant pattern due to mutations in the NF2 gene located on chromosome 22.
What are the common signs of Neurofibromatosis type 1 (NF1)?
Features include café-au-lait spots, neurofibromas (benign tumors), Lisch nodules (iris hamartomas), and skeletal deformities (e.g., scoliosis).
True/False: Patients with NF1 can present with learning disabilities.
True. Cognitive impairment is a common feature in NF1.
What are the typical features of Neurofibromatosis type 2 (NF2)?
NF2 is characterized by bilateral vestibular schwannomas, hearing loss, and balance issues.
What are the diagnostic criteria for Neurofibromatosis type 1 (NF1)?
The diagnosis is made with two or more of the following:
Six or more café-au-lait spots
Two or more neurofibromas
Freckling in the axillary or inguinal regions
Optic glioma
Lisch nodules
A first-degree relative with NF1
How is Neurofibromatosis type 2 (NF2) diagnosed?
Diagnosis is confirmed by the presence of bilateral vestibular schwannomas, often with MRI imaging.
What investigations are useful in diagnosing Neurofibromatosis?
MRI of the brain and spine, genetic testing, and audiological assessments (for NF2) are key investigations.
What is the management approach for Neurofibromatosis?
Management is symptomatic, focusing on regular monitoring of tumors, surgical removal of problematic neurofibromas, hearing aids for NF2-related hearing loss, and addressing complications like scoliosis or cataracts.
True/False: There is a cure for Neurofibromatosis.
False. There is no cure, but treatment is supportive.
What are common complications of Neurofibromatosis type 1 (NF1)?
Complications include malignant transformation of neurofibromas, learning disabilities, optic gliomas, and skeletal deformities like scoliosis.
What are the complications associated with Neurofibromatosis type 2 (NF2)?
Complications include hearing loss, balance difficulties, and other cranial nerve deficits.
What is a peripheral nerve injury?
: A peripheral nerve injury occurs when there is damage to the nerves outside the brain and spinal cord, often leading to loss of sensation, movement, or autonomic function in the affected area.
What are the common causes of peripheral nerve injuries?
Causes include trauma (e.g., cuts, fractures, compression), systemic diseases (e.g., diabetes), infections, and toxins (e.g., alcohol).
What are the main classifications of peripheral nerve injuries?
The injuries are classified according to Seddon’s system:
Neurapraxia: Temporary nerve conduction block.
Axonotmesis: Axonal damage with preservation of the nerve sheath.
Neurotmesis: Complete disruption of the nerve, requiring surgical repair.
What are the clinical features of a peripheral nerve injury?
Symptoms include numbness, tingling, weakness, and paralysis in the affected region. Depending on the nerve involved, there may be sensory and/or motor deficits.
What are common signs of a radial nerve injury?
Wrist drop (inability to extend the wrist or fingers) and loss of sensation over the back of the hand.
What are the clinical features of median nerve injury?
Symptoms include “ape hand” deformity (inability to oppose the thumb), loss of sensation over the lateral palm, and weakness of the flexor muscles in the forearm.
What is the clinical presentation of ulnar nerve injury?
Weakness of the hand muscles, leading to “claw hand” deformity, and loss of sensation over the little finger and half of the ring finger.
What investigations can be done to diagnose peripheral nerve injuries?
Investigations include clinical assessment, electromyography (EMG), nerve conduction studies, and imaging (e.g., MRI) to rule out structural abnormalities.
What are the management options for peripheral nerve injuries?
Management involves:
Conservative management: Rest, splinting, and physiotherapy.
Surgical management: For more severe injuries (e.g., neurotmesis), nerve repair or grafting may be required.
What is the initial management of a traumatic peripheral nerve injury?
Initial management involves assessing the extent of the injury, immobilizing the affected area, and referring to a specialist for further evaluation.
What are the common complications of peripheral nerve injuries?
Complications include chronic pain (e.g., neuropathic pain), muscle atrophy, and permanent sensory or motor deficits.
What is Carpal Tunnel Syndrome?
Carpal Tunnel Syndrome occurs due to compression of the median nerve at the wrist, resulting in numbness, tingling, and weakness in the hand, especially the thumb, index, and middle fingers.
What is Saturday Night Palsy?
This is a radial nerve injury caused by prolonged compression of the upper arm (often when resting the arm on the back of a chair), leading to wrist drop.
What is Thoracic Outlet Syndrome?
This condition is caused by compression of the brachial plexus or subclavian artery between the collarbone and first rib, leading to pain, numbness, and weakness in the arm
What is the prognosis for a peripheral nerve injury?
The prognosis depends on the severity of the injury. Neurapraxia typically recovers within weeks to months, while axonotmesis may require months for full recovery. Neurotmesis often results in permanent deficits unless treated surgically.
_______ nerve injury results in wrist drop.
Radial
______ nerve injury leads to “ape hand” deformity.
Median
The “claw hand” deformity is associated with _______ nerve injury.
Ulnar
T/F: Peripheral nerve injuries always require surgical intervention.
False. Many injuries can be managed conservatively with rest and physiotherapy.
T/f: Carpal Tunnel Syndrome is a form of radial nerve injury.
False. It involves compression of the median nerve.
Peripheral neuropathies can be classified as _________ vs _________, symmetrical vs asymmetrical, and _________ vs _________ based on fibre type.
acute; chronic; motor; sensory.
True/False: Peripheral neuropathies are most commonly idiopathic, with diabetes being the leading known cause.
true
List five common causes of neuropathy.
Diabetes mellitus (DM).
Vitamin deficiencies (e.g., B12).
Inflammatory diseases (e.g., GBS, vasculitis).
Infectious diseases (e.g., Lyme disease, HIV).
Toxic exposures (e.g., alcohol, chemotherapy).
Guillain-Barré Syndrome (GBS) is an example of an _________ neuropathy, while Charcot-Marie-Tooth disease is an _________ neuropathy.
inflammatory; inherited.
True/False: Copper deficiency and zinc toxicity are examples of metabolic causes of neuropathy.
true
A 65-year-old man with type 2 diabetes complains of numbness in his feet for 12 months, worsening at night. Examination shows globally absent reflexes and a positive Romberg sign. What is the likely diagnosis?
Diabetic sensory neuropathy.
A 55-year-old woman with Sjögren’s syndrome presents with foot numbness and hand weakness. Examination reveals impaired pinprick sensation in the hands, foot drop, and diminished reflexes. What is the likely diagnosis?
Vasculitic multiple mononeuropathy.
Acute onset of ascending progressive weakness, hyporeflexia, and acroparaesthesia suggests _________.
Guillain-Barré Syndrome.
What are common symptoms of peripheral neuropathy?
Pins and needles.
Numbness.
Muscle cramps and weakness.
Allodynia (painful response to non-painful stimuli).
Balance difficulties.
The “inverted champagne bottle” appearance of leg wasting is seen in _________.
Charcot-Marie-Tooth (CMT) disease.
True/False: Proximal weakness in neuropathy is more likely in inflammatory conditions like CIDP or GBS.
true
What are the hallmark features of Guillain-Barré Syndrome?
Acute ascending weakness.
Hyporeflexia or areflexia.
Symmetrical sensory disturbances.
Preceding infection (e.g., Campylobacter).
Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) differs from GBS in that its progression lasts _________ weeks or more.
8
Raised CSF protein with low or normal cell counts suggests _________.
Guillain-Barré Syndrome.
How is diabetic peripheral neuropathy managed?
Glycemic control.
Pain management (e.g., duloxetine, pregabalin).
Exercises to improve nerve fiber regeneration.
Foot care to reduce falls risk.
What are essential investigations for peripheral neuropathy?
Blood tests: FBC, glucose, B12, TFTs, ESR.
EMG/NCS for nerve conduction.
Lumbar puncture for CSF protein.
Nerve biopsy in atypical cases.
True/False: Nerve conduction studies differentiate between axonal and demyelinating neuropathies.
true
Hereditary neuropathies like CMT are typically _________, _________, and _________-dependent.
symmetrical; length; motor or sensory.
What are key features of Charcot-Marie-Tooth disease?
Slowly progressive distal muscle weakness.
Pes cavus (high-arched feet).
Sensory loss.
Hammer toes.
When should patients with neuropathy be referred to a specialist?
Acute or rapidly progressive symptoms.
Severe functional limitations.
Asymmetrical or multifocal involvement.
Motor-predominant neuropathies.
Associated dysautonomia.
Guillain-Barré Syndrome is managed with _________ or _________ to address the underlying autoimmune process.
IVIG; plasma exchange.
True/False: CIDP responds well to corticosteroids and IVIG in most cases.
true.
What are the main differential diagnoses for peripheral neuropathy?
Diabetic neuropathy.
Inflammatory neuropathies (GBS, CIDP).
Vitamin deficiencies (e.g., B12).
Inherited conditions (e.g., CMT).
Toxic neuropathies.
In neuropathy, motor-predominant symptoms often suggest _________ or _________.
CIDP; multifocal motor neuropathy.
True/False: Recognition of red flags and timely specialist referral can significantly improve outcomes in peripheral neuropathy.
true.
