Orthopedic surgery or orthopedics, also spelled orthopaedic[s], is the branch of surgery concerned with conditions involving the musculoskeletal system. Orthopedic surgery or orthopedics, also spelled orthopaedic[s], is the branch of surgery concerned with conditions involving the musculoskeletal system. Orthopedic surgery or orthopedics, also spelled orthopaedic[s], is the branch of surgery concerned with conditions involving the musculoskeletal system. Orthopedic surgery or orthopedics, also spelled orthopaedic[s], is the branch of surgery concerned with conditions involving the musculoskeletal system.