A lower extremity mobilizer for use in rehabilitation is provided. A seat is slidably maintained upon a base, with a foot support brace being provided at an end of the base to receive the foot of a leg provided for arthrokinematic treatment. A cord and pulley system is provided between the seat and the end of the base. In use, a patient is seated with a foot received by the foot support brace. The patient provides arthrokinematic motion to his leg by pulling himself and the seat toward the end of the device having the foot support brace. The procedure is undertaken in a closed chain motion, with the foot constantly engaging the foot support brace, and is done so as a rate, timing and extent under the control of the patient.