A system for maintaining a desired spinal curvature of a user suffering from improper alignment of the vertebrae of the spine. In it's broad aspects, it comprises a sensor feedback system and electrodes. The sensor feedback system measures spinal curvature, determines whether selected conditions have been met warranting the application of electrical stimulation and provides information regarding the determination to an electronic stimulator. The electrodes are spaceably mounted on selected portions of the user's back. They are in electrical communication with the electronic stimulator for causing contraction of the back muscles at selected levels, thus providing alignment of the spinal vertebrae. The sensor feedback system includes a sensor assembly which comprises an upper elongated rigid segment, a lower elongated rigid segment and a sensor. The upper elongated rigid segment is positionable adjacent the user's upper spine. The lower elongated rigid segment is positionable adjacent the posterior pelvic region. The sensor is mounted on a flexible middle segment between the upper segment and the lower segment. The sensor is so positioned as to measure lordosis.