Brief Answer:
Muscle atrophy seems likely; need more information, speak to your doctor

Detailed Answer:
Hello ma'am and welcome.

Thank you for writing to us.

I have gone through your query with diligence and would like you to know that I am here to help. It appears as though, from your description (although cannot be sure without a physical examination) that there could be some muscle atrophy in the region described by you.

I have a few more questions to better understand the possible cause, they are:

+Do you have any trembling or tremors in your hand?
+Difficulty in holding things with that hand?
+Can you button or unbutton your shirt? Or you feel some amount of difficulty or resistance?

Muscle atrophy is a common side effect of various medications, and so I would like you to run through your medications with your prescribing doctor to make sure muscle atrophy is not one of the possible side effects; and if it is then please discuss substituting those medications that can possibly cause muscle atrophy with safer ones.

I hope you find my response helpful. Please do not hesitate to write back to me for any further clarifications, I am always here to help.

Best wishes.

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Brief Answer:
Then there is nothing much to worry about, but better get checked still

Detailed Answer:
Hello ma'am and welcome.

If the sink is not permanent and you are not experiencing any debilitation with your fine movements, there should be nothing to worry about. However, I would still be much more comfortable if you can visit your physician about the same and also ask for a neurologist opinion, just to make sure we rule my worries out completely and so you can continue to live a comfortable and healthy life.

Please also do not hesitate to write back to me for any further clarifications, I am always here to help.

Best wishes.

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