Brief Answer:
entrapped nerve is unlikely.

Detailed Answer:
Hello!

Welcome to Healthcare Magic.

I read carefully your query.

If your only symptom is a vibration sensation coming from neck ,it is less likely to be due to a neurological problem like an entrapped nerve.A vibration sensation very rarely is due to a neurological cause.
An entrapped nerve is a condition when nerve roots are compresses by surrounding tissues like a herniated vertebral disc,arthritis of cervical vertebra etc.
In this case you would experience neurological symptoms in the area controlled by the compressed nerve ( in this case would be in neck and arms ) including burning pain, numbness or decreased sensation , "pins and needles" sensations ,muscle weakness.
These symptoms would be associated with specific neurological findings on physical examination and X-ray or other studies (CT-scan ,MRI) would have shown the cause of this compressed nerve.

The fact that your don't have other symptoms associated with this vibration sensation ,no neurological findings of physical examination (since your doctor suggested to be muscle spasm means he didn't find any specific finding on examination) and since X-ray was normal , makes it unlikely to be a neurological problem.
A CT-scan and MRI of head and neck would exclude definitely any neurological cause.

So ,it is very likely to be just muscle spasm due to bad posture or overworking the muscles in your neck.
Sometimes anxiety and stress can trigger symptoms of vibration sensations and muscle twitching in some part of the body.
Since major causes for such symptoms have been excluded ,you don't need to worry.
Try to rest ,eat healthy ,drink plenty of water and exercise regularly.

Hope this is helpful to you.
Let me know if you have any other question or doubt to clarify.I will be happy to assist you further.

Kind regards,
Dr.Rovena Murati

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