The first thing to consider is where the pain may be coming from. It can be coming from the wrist, maybe forearm, it could be carpal tunnel? You have to weigh the patient's history if you're the doctor. If you're the patient, think of what you do - for work, leisure, past and present injuries, health conditions...
If you sit at a computer with poor ergonomics and type all day maybe it is carpal tunnel syndrome! But maybe it is neck related. You may not have pain or other symptoms there but it can be the root cause. You see messages come from our brains to spinal card, to nerve roots (bundle of nerves) to nerves and travel all the way down the arm to the hand and fingers.
If your pain is in your hand, especially the thumb, index, or middle finger, or all of them; the neck may be responsible. You see it really will depend exactly where the pressure is. If it's a the nerve root level it can actually affect a number of different nerves. This is often a result of a disc injury, some stenosis, or significant inflammation.
Another factor is, how long has this pressure been there? The longer we've had it then the greater chance to do significant and sometimes permanent damage. Also, over time we can develop more degeneration; in other words, arthritis. This is how stenosis will occur. The discs flatten and bulge, inflammation accumulates, and arthritis can form into bone spures and jagged edges. This contributes to closure of the foramen (holes on each side of the spine) the nerves exit out of.
Also, your age and level of health is a contributing factor. As we age, breakdown occurs. This is another way to say arthritis. Now, depending on how well you take care of youself and genetics will say if you have severe degeneration to hardly any at all.
We can also look to the anatomy as to why we will get symptoms on one side vs both hands and fingers. Is pressure pushing on the spinal card itself, so it's effecting both sides or is it more on the left or right nerve root?
Of course, the pain can be lower down. More on an actual nerve or nerves vs the actual nerve root. You may have muscle spasm up near the neck that is causing the issue.
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