An apparatus and method for detecting, monitoring, measuring and recording the motion of a patient's spine is disclosed. The apparatus includes a vertical member attached to a belt that fits around the patient's waist. A first sensor for detecting and monitoring flexion and extension of the patient's spine in the midsagittal plane is mounted to the lower end of the vertical member. A second sensor for detecting and monitoring lateral bending and movement of the patient's spine in the frontal plane is mounted to the upper end of the vertical member.