Have you had nerve conduction studies on your affected hands ??
The thumb to half ring finger distribution could be due to carpal tunnel syndrome as most common culprit for this part of the hand going numb and you having weakness of hand
The little finger and lateral half of ring finger going numb is different nerve distribution..
That could be an ulnar nerve entrapment
Yes thoracic outlet syndrome could lead to many of these symptoms and also possible that cervical disk disease and nerve root compressions in the neck could explain symptoms ...
These are a group of possible diagnoses that may relate
An orthopedic specialist should be helpful or neurologist for help to diagnose your source
I hope that this information is helpful for you
Let me know if you have further questions or concerns
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Thank you and Best Regards,
Anthony Bray MD