Splints are often custom fitted by the hand therapist to rest, protect or mobilize an injured segment. For example with carpal tunnel syndrome a splint may be applied to a wrist to keep it in a neutral position to relieve pressure of the median nerve in the carpal tunnel. Following a wrist fracture, a splint may be applied to increase bending of the wrist. Splints are commonly made from a low-temperature plastic, or neoprene material.

Casts are used to immobilize a fracture, or correct a joint contracture. The hand therapist uses a series of plaster casts as a treatment to correct contractures. The physician uses a cast to immobilize a broken bone, for example after a wrist fracture. This immobilization cast may be constructed from plaster or fiberglass.

Brace is a term not often used by hand therapists. Sometimes people will refer to their splints as braces. Braces tend to be heavy duty, and more commonly are used to describe neck, back, or leg supports.