“An avid guitar player since the 70's they have developed a sharp pain in both hands around the thumb muscles from overuse over many years while playing the guitar.”
Solutions to this are all about balance. They can lower the pain by distributing their demand on the thumb across the entire hand. Some of this will be about changing habits, and some may well be about how to pull power from other places.
I’d like to share these stories gleaned over the years as a practitioner of Structural Integration (‘Rolfing’). If you like the idea, let me know, ok?
[Caveat: I am not a doctor. I am not permitted to ‘fix’ you. Or even suggest so.]
Start here .. (location, nature, and timing)
So while we know there is pain in the thumb, can we get more specific? We know there is pain is in the thumb, though where exactly? At the base of the thumb where it meets the palm? Back (dorsal) or front (ventral) side of the palm?
Does the pain extend to the elbow? To the shoulder, side of the neck? Do any of these places become numb?
When exactly does the pain occur? “Playing bar chords on the guitar, shoveling, walking.”
Dig a bit deeper ..
Do you have nerve sensation (e.g. numb, raw, tingling feelings) in your wrist, elbow, shoulder, neck? Nerves can be impinged at any of these junctures. And, if so, which activities highlight the pain at which location(s)?
And have you ever injured your hand or arm in the past? (You know, this is where they recall the time they were playing with a hammer on the Playa, and ....)
And offer a few ideas ..
1) Balance the stress on the joint by distributing power through all the joints
Strengthening the other fingers first. Get a ball and begin strengthening the entire hand. Your thumb has probably been picking up the whole load. Not cool. Same thing for the wrist. Begin doing some lifts with small weights to exercise the wrists. This is a project. Build the strength over time. You may notice some results in a 2-3 weeks, if you behave.
2) Change the way you use the joints
If your palm is in a ‘broken’ position, meaning the back of your hand is closer to your forearm (less than 90 degrees), reverse this habitual position so the front of your palm is closer to your forearm. This is key.
Check whether the angle created by your pinky and your wrist is acute as well (pinky closer to wrist). If so, get the thumb side of your hand closer to your wrist.
So in the end your wrist will be curved in with the thumb side closer. Should take some pain out, plus give you back some of your power.
Finally, I’d see whether you could control more of your movement from your elbows (and even shoulders). So rather than driving from the base of the thumb, control it from your shoulder.
3) Work with a wizened bodyworker / doctor / physical therapist
Utilize their expertise to re-integrate the action of your thumb with that of your hand, elbow, and even breath.