This can be caused by a combination of systemic and local conditions. Local causes can be collapse of the arch structure of the wrist , fractures, dislocations, overuse, gout, osteoarthritis, scar tissue formation. While this condition was first reported almost 3 centuries ago, it is only in the last few years that extensive research on its cause and treatment has been undertaken. Put the backs of both hands together and hold the wrists in forced flexation against each other for 60 seconds. Next bend your wrist backwards and tap repeatedly on the palm side of your wrist.
Ice is very important for the reduction of swelling in the wrist.
Then adjustments to the wrist to normalize the arch structure. Also, adjustments to any accompanying elbow, shoulder, and neck problems. Splinting is no longer recommended in most cases. IF a splint is used at all it should be very flexible support worn only at night if it's difficult to sleep. Or at work a splint is worn to function as a reminder to keep the wrist straight.