What constitutes a broken wrist and how is it treated?

Wrist fracture: It constitutes a whole continuum from bone bruise, growth plate injury, greenstick fracture, nondisplaced/displaced/cominuted/intraarticular/closed, all the way to open fracture. Location and severity determine the treatment: splint or casting, up to surgical intervention of ex fix, orif, pins, plates and screws, etc.

Depends: A distal radius fracture can be treated in a cast or by surgery and heals in about six weeks. A scaphoid fracture if non-displaced can be treated in a cast and heals in 6-12 weeks. If the scaphoid fracture is displaced it needs to be operated on. Triquetrial avulsion fractures heal in a splint in 4-6 weeks. Other wrist fractures are unusual. See a hand surgeon.