I think i know what are you referring to. Please do a few test to confirm where is the problem.
1) put your hand palm face on the table relax, arm remain straight and relax off the table. Try to rise your fingers without any help.
2) stand close to the wall and straighten your arm n palm flat on the wall.. slowly push into the wall causing your wrist at 90 deg bend.
3) grip your knuckle tight, straighten arm forward like trying to punch someone in front, slowly lift your knuckle.
Which exercise do you feel pain at the wrist?
Use the other hand, Grip your injured wrist with your thumb onto the area whereby a watch face will be if your wear a watch on the injured wrist and repeat the exercise. Any pain?