Muscle & Nerve Disease Flashcards
Which type of energy does muscle receive and what does it convert it into?
Chemical energy -> mechanical energy
In muscle disease, which symptoms would a patient present with?
Weakness of skeletal muscle
Cardiac symptoms
Cramps/muscle pain
Muscle stiffness
Myogloburia
Myogloburia?
Breakdown product of muscle in the urine suggesting muscle is being broken down
How will muscle disease present in babies?
Floppy, poor suck/feeding, failure to thrive
Are muscle diseases purely motor or sensory?
Motor
-> do not get sensory symptoms
Which investigations may be carried out to diagnose someone with muscle disease?
History and examination
Bloods
Electromyography (EMG)
Muscle biopsy
Genetic testing
What would be looked at in bloods in someone with suspected muscle disease?
Creatine kinase
->maybe remember that all gym lads take creatine for muscle
If muscle is damaged, what will creatine kinase levels be like?
Elevated
-> creatine kinase is a an enzyme produced when there is muscle damage
There are congenital and acquired causes of muscle disease.
Congenital causes tend to affect the components of muscle.
If there were congenital contractile issues, what might occur?
Congenital myopathies
There are congenital and acquired causes of muscle disease.
Congenital causes tend to affect the components of muscle.
If there were congenital structural issues, what might occur
Muscular dystrophies
There are congenital and acquired causes of muscle disease.
Congenital causes tend to affect the components of muscle.
If there were congenital coupling issues, what might occur?
Channelopathies
There are congenital and acquired causes of muscle disease.
Congenital causes tend to affect the components of muscle.
If there were congenital energy issues, what might occur?
Metabolic myopathies
Which electrolyte disturbance can cause muscle weakness?
High or low levels of potassium
Which vitamin deficiency can cause muscle weakness?
Vitamin D
Inflammatory muscle diseases are usually autoimmune. Which two types are there?
Polymyositis
Dermatomyositis
What inflammation is present in polymyositis?
Inflammation of muscle alone
What inflammation is present in dermatomyositis?
Inflammation of skin and muscle
How do inflammatory muscle diseases present?
Muscle weakness, rash and pain
What is the treatment for polymyositis and dermatomyositis?
Immunosuppression
What would be seen in bloods of someone with an autoimmune inflammatory muscle disease, like polymyositis or dermatomyositis?
High creatine kinase
Autoantibodies
Which type of inflammatory autoimmune muscle disease is associated with underlying tumour?
Dermatomyositis
Which investigations may be carried out to diagnose polymyositis and dermatomyositis?
Bloods
Tumour screen- especially in dermatomyositis
EMG
Biopsy
Which enzyme breaks down acetylcholine?
Cholinesterase enzyme
What is myasthenia gravis?
Rare long-term condition that causes muscle weakness
What is the clinical presentation of myasthenia gravis?
Fatigable weakness
->patients complain they get weaker as the day goes on or continue with muscular activity
There are two forms of myasthenia gravis. Name them.
Ocular myasthenia gravis.
Generalised myasthenia gravis.
What are the symptoms of ocular myasthenia gravis?
Ptosis
Diplopia
What are the investigations used to diagnose myasthenia gravis?
Assess for ACh receptor or anti-MuSK antibodies in blood
Neurophysiology- EMG
CT chest
What is the symptomatic treatment for myasthenia gravis?
Cholinesterase inhibitors
What is the disease-modifying treatment for myasthenia gravis?
Immunoglobulin/plasma exchange
Steroids
Steroid sparing immunosuppression
Thymectomy
->these all try to get rid of the antibody causing the effects
Name the two components of a peripheral nerve.
Lower motor neuron component
Sensory neuron component
There are small and large sensory fibres in peripheral nerves. Which fibres carry pain and temperature?
Small fibres
There are small and large sensory fibres in peripheral nerves. Which fibres carry joint position sense and vibration?
Large fibres
RECAP- what is the function of the myelin sheath?
Wraps around axons to speed up electrical conduction down myelinated nerves
If there is damage to the nerve root, this can cause root disease. What is a common cause of root disease?
Degenerative disc disease
How may a single peripheral nerve get damaged?
-If it gets trapped or compressed (e.g. ulnar nerve getting trapped to give ulnar neuropathy or median nerve getting trapped to give median neuropathy)
-If you damage a nerve’s blood supply
Will a generalised peripheral neuropathy affect motor or sensory components of the nerve?
Either or both
In generalised peripheral neuropathy, which components of the peripheral nerve can get damaged?
Axonal component
Myelin sheath
What are the most common causes of generalised peripheral neuropathy?
Alcohol
Diabetes
Are inflammatory autoimmune generalised peripheral neuropathies usually axonal or demyelinating?
Demyelinating
Give an example of an acute inflammatory autoimmune generalised peripheral neuropathy.
Guillain Barre syndrome
Give an example of an chronic inflammatory autoimmune generalised peripheral neuropathy.
Chronic inflammatory demyelinating polyneuropathy
What are some of the sensory symptoms of peripheral nerve diseases?
Loss of sensation/abnormal sensation
Pain
What are some of the motor symptoms of peripheral nerve disease?
Muscle thinning and weakness
What are some of the autonomic symptoms of peripheral nerve disease?
Skin changes e.g. discoloration/altered sweating
Blood pressure
Bowel and bladder changes
Give some examples of sensory signs of peripheral nerve disease.
Reduction in light touch, temperature, joint position, vibration sensation.
Will the motor signs in peripheral nerve disease be upper or lower motor neuron signs?
Lower motor neuron
Which signs would you expect to see in someone with lower motor neuron damage?
Muscle wasting
Loss of tendon reflexes
Loss of muscle tone
Muscle fasciculations
Which nerve gets damaged in carpal tunnel syndrome?
Median nerve
In generalised peripheral neuropathies, are the effects initially distal or proximal?
Distal- effect feet first
Which investigations may be carried out when suspecting someone of having peripheral nerve disease?
Blood tests
Nerve conduction studies
Lumbar puncture
Nerve biopsy
Genetic analysis
What is the treatment for peripheral nerve disease?
Treat the cause e.g. stop drug, surgery for trapped nerve, etc.
Which neurons are affected in Moto Neuron Disease?
Upper and lower MN
In which part of the body does motor neuron disease typically present?
Limb
After affecting the limbs, where will motor neuron disease spread to?
Bulbar muscles and then respiratory muscles
In motor neuron disease, patients can present with a combination of upper and lower MN signs.
Give some examples of LMN signs they may present with.
Muscle fasciculation
Muscle wasting
Muscle wasting
Q
In motor neuron disease, patients can present with a combination of upper and lower MN signs.
Give some examples of UMN signs they may present with.
Spasticity
Brisk reflexes
Extensor plantars
Is there any sensory involvement in motor neuron disease?
No
What is another name for motor neurons disease?
Amyotrophic Lateral Sclerosis
What is the prognosis for MN Disease?
Median die 3-5yrs from symptom onset/ 2-3yrs from diagnosis
50% die within 14months of diagnosis
How is MND diagnosed?
-Pure clinical diagnosis so based on history and particularly examination as has the unique combination of UMN and LMN signs
-EMG
What is the treatment for MND?
Supportive- physio, OT, SALT, PEG feed, non invasive ventilation, care
Palliative care
There are not many drugs to slow MND and no cure. There is only one drug licenced for use which can improve survival by approx. 6 months. What is it?
Riluzole
Just to recap- in peripheral nerve disorders, what will the symptoms and signs be a mix of?
LMN and sensory
