What is the difference between the terms "skeletal" and "orthopaedic"?

Defined: Skeletal refers to that which relates to the bony elements of the body, including bones, joints, and ligaments. Orthopedic refers to the field of musculoskeletal medicine, derived from the literal latin meaning leg.

Bones, etc.: "skeletal" is a term referring to bones. "orthopaedic" literally translates to "straight children" and refers to the specialty that cares for musculoskeletal diseases and injuries (involving bones, joints, muscles, tendons, and ligaments), and can trace its roots to straightening children - something still done by many pediatric orthopaedic surgeons.

Medically the same: orthopedics is that field of medicine that deals with the musculoskeletal system