Brief Answer:
Listed a few of the most likely causes for your reference ma'am :)

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. There are a few possibilities for such a presentation, and I would like to start by listing a few of the most likely ones out for you, and then take it from there. They are:

+Raynaud's disease: A condition in which the arteries in the fingers go into spasm, and thus disturbing the circulation to them (blood test to confirm/rule out)
+Arthritis: Inflammation of one or more joints which can also interrupt the circulation (test using a blood test called RA factor)
+Thyroid abnormalities: Usually an under functioning thyroid abnormality which can cause a similar presentation and requires a thyroid profile (blood test)
+Scleroderma: Hardening or tightening of the skin or connective tissues; in your case in the finger, thus causing a circulatory disturbance
+Occupational, professional or daily routine causes: To do with how much you use your finger, which can result in overuse and the picture you are seeing
and a few others.

All the above listed causes will require a physical examination and a few blood tests to actually narrow it down to the cause, so we can treat you and prevent any progression. So please do find time and visit your doctor who I am sure will diagnose and treat you accordingly.

I hope you find my response helpful and informative. 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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