Falls from a standing position that are not caused by tripping over something or being pushed are referred to as low energy trauma. It sounds like this is the type of injury that caused your father’s fracture.
Older adults are the group at greatest risk for this type of fall and associated injuries. Osteoporosis (brittle bones or decreased bone density) increase the risk of fractures from low energy trauma.
Physical therapy and rehab isn’t routinely required after wrist fractures. But anyone with loss of motion, stiffness, and persistent pain can benefit from some exercises to help restore normal activity. Without full wrist motion and grip strength, every day activities can become a real problem. Even lifting a plate of food or coffee pot can end in disaster.
It’s important to prevent further accidents and alleviate any suffering. It might be a good idea to see that the exercise program is done several times each week. If you are unable to do this yourself, there are home health agencies who send in a therapist to work with your father.