Thank you for posting your query.
The most common cause for muscle twitching on your legs could be a condition called as benign fasciculations. This is not a serious condition, and would subside on its own. However, you should watch for muscle wasting (thinning of muscles) and weakness, when you would need to see a neurologist
to exclude other conditions such as ALS.
Bulging neck vein is normal and in the absence of symptoms (such as breathlessness), there is no need to worry.
I hope it helps. Please get back if you require any additional information.
Wishing you good health,
Dr Sudhir Kumar MD (Internal Medicine), DM (Neurology)
Senior Consultant Neurologist
Apollo Hospitals, Hyderabad, India
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