Abstract: A device for monitoring the flexion, extension, and rotation of a user's torso. An upper and a lower sensing arm extend vertically in opposite directions from a measuring and control box that is held about the midsection by a belt, and both arms are spring biased to hold them against the user's back. The torso engaging portions of each of the sensing arms are curved to cup the engaged portion of the anatomy and thus allows for the sensing of torso rotation due to a pair of protrusions integral to the sensing arms and ensconced within the control box. Both arms are telescopically adjustable to allow the device to be fit to differently sized people and the amount of flexion, extension, and rotation that is allowed by the device before a warning tone is sounded is adjustable.