I am Dr. Arun and will be helping you today.
I am sorry that your question was unanswered for long.
This sensation is called paresthesia and can be due to pinched nerves in back. This can be due to;
1) Herniated/degenerated disc in back
2) Lumbar spondylosis; bone spurs in the back vertebrae pressing on the nerves.
Following investigations would be required;
1) X-ray of the lower back
2) MRI of the spine
3) Nerve conduction velocity (NCV) study
4) Electromyography (EMG)
Physical therapy is the mainstay of the treatment.
Your symptoms may also occur due to neuropathy which can be secondary to;
2) Vitamin B 12 deficiency
4) Metabolic disorders.
A blood work would be required to diagnose the above.
Please feel free for your follow up questions.
I would be happy to assist you further, if you need any more information.
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