I am Dr. Arun and will be helping you today.
I am sorry that your question was unanswered for long.
The left hand tremor may be caused by whiplash / pinched nerves in neck. You may get the following investigations done, if not already performed:
1) MRI of neck and brain.
2) Electromyography (EMG)
3) Nerve conduction velocity study (NCV).
4) Throid function tests.
5) Blood electrolytes and serum calcium.
These would be able to pin point the cause and thereby indicate the treatment.
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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