Brief Answer:
Probably carpal tunnel syndrome.

Detailed Answer:
Hello and thanks for using HCM.

I have read your question and understand your concerns.

Losing strength in one hand is primarily linked to carpal tunnel syndrome, or compression of median nerve.

This is true especially if there are other symptoms such tingling, numbness mostly at night.

Other less possible conditions that need to be considered include muscular conditions and impaired blood supply of the hand due to arterial narrowing.

It is necessary to be evaluated by your primary care Doctor about these conditions.

It is also necessary for nerve conduction study, EMG of the affected arm and hand.

Hope you found the answer helpful.

Let me know if I can assist you further.

Take care.

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Brief Answer:
Electromyography.

Detailed Answer:
Welcome back.

EMG stands for electromyography, it is a test that evaluates nerves and muscles function.

Hope this helps.

Regards.

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