hold the hand that hurts palm facing towards you - let's say right hand....

with the finger and thumb of your other hand - left hand....

you put the left hand thumb on the wrist bone that sticks up (level with your little finger)

and you put your fingers behind the other side of the wrist

a bit like a doctor taking a pulse but on the bones

on the back side of your hand that faces away from you - there is the other part of the bone joint from your arm

so on your thumb you will feel the lump of the bone at the bottom of your hand

and on the back side of your hand that faces away from you - with your left hand fingers you will feel the bone of your lower arm where it joins the wrist.

hold with your fingers on the back side and press with your thumb you will see you can work the joint, pressing the lump of the hand bone away from you with your thumb

you can losen the joint up like that

it's a bit like when you carry a heavy bag and then put it down and your fingers are all locked and stiff - in that case it goes away on it's own

in this case you loosen the joint yourself

i should make a video of it - a physio taught it to me - never had a problem since... do it all the time... there are about 3-4 exercises...