Finger Issues

Hi,
I've been hanging around the DIY board for a while, but I thought I would come over here and ask about an issue that has been plaguing me recently.
Over the past year, I have been adding a lot of Hendrix and Hendrix-inspired (McCready, Frusciante, etc.) tunes to my practice sessions.
While I've made some attempts to bring my thumb around, to help out on the low E, I don't as yet have the hand geometry, flexibility, neck geometry, or some combination, to play well that way. I can see that breaking out of "the claw" has its advantages and I'll keep working on it. But, for now...
My tendency is to barre all six strings and work out ways to add Hendrixian embellishments and flourishes with any 'free' fingers I can manage. All in all, I'm playing many of these tunes rather proficiently. However, I think I'm heading toward the dark terrain of overuse injuries.
As I sit here and take inventory, my left thumb feels like I've compressed a nerve and numbed the inside half of the pad, from the knuckle to the tip. The first and second joints of my left index finger, feel a mild, but humbling, arthritis pain (making a fist, is about a 5 on a 10 scale). Finally, the contact point of my pinkie (the very tip, where string contact is made) is also pretty numb.
I've decided to give my hand a rest and turn to finishing some build projects, at least until the numbness leaves.
In the meantime, I am keen to learn effective massages, warmups, stretches, etc. that will help minimize the stiffness. I suspect the nerve compression was a result of trying to barre too hard, on a tired thumb (which rolled onto the side, where the nerve resides). Has anyone found an online (or other) resource for such techniques? A friend tells me I should get a paraffin wax bath. Any here have experience with that?
Has anyone else overcome difficulties incorporating the thumb technique? Where should I start (neck shape, finger flexibility, other)? Any tips are appreciated. To give a bit of background, I have big hands (I can palm a basketball) and played bass for decades, before switching to 6 and 12 string. My fingers are thick (ring size 13-1/2), but strong and nimble (or were).
Help?

As far as the injury itself is concerned - I'm afraid I can't really be of much assistance!

With regards to warmups I have 2 suggestions

1 - http://www.youtube.com/watch?v=1XsLRQFV7rY

2 - http://books.google.co.uk/books/about/Mel_Bay_s_finger_gymnastics.html?id=fAzp6e18Qh4C&redir_esc=y

With regards to the thumb, I'm not really sure if your thumb will ever be able to do what Hendrix's thumb could do... Have you seen the size of his thumb?! :shock:

I think if you work at it, you'll get a hand position working that enables you to fret the root notes for barre chords on the 1st string etc. Which is still pretty useful IMO... Tommy Emmanuel preaches the importance of this - Angus Young however has TINY hands, but just listen to him play! :twisted:

I have some hand pain and numbness caused by degenerative discs in my neck.

You should see a Dr to rule out more serious causes.

Thank you for the links, Thorpey. I'm sitting at my desk, doing a few stretches right now.

I think my biggest difficulty with the thumb-over technique is that when I have the neck against my palm, the first knuckle and pad of my thumb are hovering high above the fretboard. My thumb, bent to about 90deg at the 1st knuckle, bunches up into a soft bump near the knuckle crease. I can manage to weakly press on the string with that pad, but not enough to guarantee a clear tone. It is difficult to see how I would get my thumb tip down firmly and still have the rest of my fingers in a practical position. I am wondering if the solution might be a big, fat, "baseball bat" neck.
Thank you for the advice Mike. I'll be sure to bring this up with my doc.

V necks are best for the thumb over style. Not mandatory, but make it easier.

Spinal Stenosis? I can easily bar the E and A strings with my thumb. Been doing it forever. But as I've gotten older, I'm having signs of some numbness in my fingers. Nothing bad yet. But my feet? Numb! Neck shapes might help you. Don't know fur shure. But then,,,, I'm 66 this October, and have had two serious back injuries. Compression fractured three disks in a fall. 7 months in bed.

Yeah sometimes the pain or numbness in your hand is the "effect, not the "cause". Problems with your back or shoulders can cause undue stress on your elbow with causes stress in your wrists. Stretching and warm-up are great but only part of the equation. When practicing, sit in front of a mirror and pay attention to your posture. Are you slouching? Are you dropping your shoulder? How low is your guitar hanging when you play? Is it putting your wrists in an awkward position? When practicing set an egg timer for 20 minutes when the egg timer goes off get up and walk around or stretch you back for 5 minutes than go back to practice, again setting the egg timer for 20 minutes. The frequent breaks will be good for you.