Surgery of joint of hindfoot (other than ankle) or first metatarsophalangeal joint, by arthroscopic means, including any of the following (if performed): (a) cartilage treatment; (b) removal of loose bodies; (c) synovectomy; (d) excision of joint osteophytes; other than a service associated with a service to which another item of this Schedule applies if the service described in the other item is for the purpose of performing a procedure on the ankle by arthroscopic means—one joint (H) (Anaes.) (Assist.)