Brief Answer:
nerve compression in your neck or arm.

Detailed Answer:
Hi,

Thanks for your question.

Based on your past medical history my first objective would be to rule out further nerve compression in your neck. This could be done by getting an MRI scan of your cervical spine.

Other cause of pain and numbness in your arm could be nerve compression in the arm itself. The ulna nerve can get compressed in the cubital tunnel behind the inside of the elbow joint, the median nerve in the carpal tunnel at the wrist. These are common site of nerve compression in the arm and can be diagnosed by the distribution of the numbness in your hand and nerve conduction tests.

Saturday night palsy so called is a condition where a person wakes up with a numb weak hand from falling asleep with his arm over the back of a chair. This compresses the radial nerve. This usually recovers spontaneously but can take weeks to months.

I hope this answers your question.

best wishes

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