Brief Answer:
Consult an Orthopedic surgeon .

Detailed Answer:
Hi XXXX,
Thanks for the query under healthcare magic platform. I have read your query & understand your concern.
pain in arm can be due to various causes pertaining to bones, joints, muscles , tendons or nerves in the hand. Considering your problem of having one sided pain to start with , followed by pain at an identical site in another hand after one year I can think of following causes of your pain. They are
- Over exertion to muscles due to work can cause muscle pain on that side. Usually we work with right hand & those muscles were affected first,as a natural tendency, another hand was used for the task ( to avoid pain in right hand ) and the due to work load/ over exertion ,left hand muscles also started having pain (at the specific stressed spot by work) on the hand.
- Rheumatoid arthritis goes on affecting joints one after another.. involvement of same joint in both hands one after another can cause pain like you have.This type of arthritis also affects tendons of muscle & cause pain at it's point of attachment to bone.Affection of right arm joint / tendon followed by affection of same parts in left side can cause the pain you have.
- Pinching of nerve supplying arm in affected area can cause such pain...the pain being at an identical spots, it seems to be pertaining to disc problem at particular cervical spinal level.. the disc bulged on right hand side & compress nerve on right side of spine.. to cause nerve pain .
The cervical spine being neglected ,the degree of disc problem went on increasing to involve & prolapse on left side too & cause identical pressure on
left sided nerve & cause pain in left arm.
In this context I would suggest consultation of an orthopedic surgeon for detailed assessment of both of your upper limbs along with X ray / MRI/ Ct sacn of the part to confirm the causative factor.
Management would be cause specific along with needful rest/ medications/ physiotherapy/ surgery to manage non responding symptoms.
I hope the answer was both informative & useful to you. Any follow up query you have.. I would be happy to help.
Thanks.

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