Posterior wrist pain

[SA0526]

You're right, it absolutely seems that an underwrap should help, but I've used the white hypo-allergenic tape under leukotape, and sill got a rash in the exact shape of the taping technique used.

[violablue]

Extensor carpi radialis brevis, extensor indicis, subscapularis, scalene minimus all refer pain to the back of the wrist. Check them out at Forearm & Hand Pain
As near graduating PT student myself, I have the same pain issue from all the typing and bad study posture. If this is what’s causing the pain, rather than issues with hypermobility, you can address it by finding the offending points, working them out, and if they are causing the pain the pain should go away. Good also to figure out the source of the trigger points, to prevent future issues. Posture? Neck Tension? Repetitive typing?