Okla. Stat. tit. 59, § 887.3

No person shall designate himself as a physical therapist or physical therapist assistant, nor practice, nor hold himself out to the public as being able to practice physical therapy in this state, unless licensed in accordance with the provisions of the Physical Therapy Practice Act. The Physical Therapy Practice Act shall not prohibit or prevent any person licensed in the healing arts in this state from engaging in the practice for which he is duly licensed.