Muscle Weakness Flashcards
Muscle weakness: if a patient presents with symmetrical signs what is the likely cause?
It is likely to be a genetic or metabolic cause.
Muscle weakness: if a patient presents with asymmetrical signs what is the likely cause?
It is likely to be a vasculitic or inflammatory cause e.g. entrapment.
Give an example of a post-synaptic disorder affecting NMJ?
Myasthenia Gravis
What are the main signs of MG?
Generalised fatiguability:
- Proximal limbs.
- Neck/face - head drop, ptosis.
- Extra-occular - diplopia.
- Speech and swallowing problems.
- Risk of other auto-immune disorders.
What investigations would you do in someone who you suspect has Myasthenia Gravis?
Tensilon test.
Bloods for autoantibodies.
Ask the patient to count to 50 or hold their arms outstretched.
What is the treatment for myasthenia gravis?
- Acetylcholinesterase inhibitors e.g. pyridostigmine.
- Immunosuppressants e.g. prednisolone.
If a patient describes difficulty getting out of a chair and up stairs etc. does that suggest a proximal or a distal problem?
Proximal
What are 4 signs of UMN weakness.
1) Increased muscle tone.
2) Hyperreflexia.
3) Spasticity
4) Minimal muscle atrophy.
What are 4 signs of LMN weakness?
1) Decreased muscle tone.
2) Hyporeflexia.
3) Flaccid.
4) Muscle atrophy.
5) Fasciculations.
What metabolic disorder can cause peripheral neuropathy?
Diabetes
A patient describes a 2 week history of muscle weakness that began in his toes and is now affecting his whole legs. He reported having an infection (EBV) 2 weeks ago and also mentions that he has noticed changes in feeling and sensation. Give a possible diagnosis.
Guillian-Barré syndrome (GBS): typically post-infectious.
Important sign = ASCENDING weakness and a short history!
What investigation would you do in a patient who you suspect has Guillian-Barré syndrome?
Nerve conduction studies
What is the treatment for Guillian-Barré syndrome?
IV immunoglobulin or plasma exchange.
Carpal tunnel syndrome is an example of what kind of peripheral neuropathy?
Mononeuropathy (Affects median nerve)
Peripheral Neuropathy: describe mononeuritis multiplex.
A patchy process where individual nerves are picked off randomly. Often it has an inflammatory or immune mediated cause. Chronic, slow progression.
