After getting a cast off my arm, how long could it be before my handwriting gets back to normal?

Motion resolves fast. Stiffness after casting is expected but generally resolves relatively rapidly. Once normal wrist and hand motion resumes onthecorder of days to a week, your handwriting will normalize as well.
2-3 weeks. Regaining full strength, motion and dexterity of the fingers, hand and wrist after casting depends on several factors: age of the patient (younger = quicker), severity of the injury and length of casting. 2-3 weeks is the typical amount of time to return to normal writing for a routine metacarpal or distal radius (wrist) fracture. Squeezing a stress ball or racquetball can improve your recovery.