Rachiometer

The rachiometer consists of a rigid vertical metal rod one inch in square dimensions. It is mounted on a base which supports a set of foot plates so placed that a patient can stand in front of the rod.[…]At one inch intervals running anteroposteriorly through sleeves within the vertical stand rod, are pencil like metal pegs that readily slide back and forth. After the patient is placed in position in front of the vertical square rod, these pegs are progressively brought, from above down, in contact with the patient's back. The patient then steps away from the rachiometer and it will be noted that the placed anterior tips of the pegs describes the spinal curves.

Biomechanical instruments, such as the rachiometer and posturometer, have been developed to record spinal curvatures and relate these to radiological findings.

To measure the spinal alignment, the angle of 17 movable parts from between the first and second thoracic vertebrae (Th1/2) to between the fifth lumbar vertebra and first sacral vertebra (L5/S1) was measured in three postures, upright, flexion, and extension positions, in the sagittal plane using a rachiometer (Spinal Mouse™, Idiag AG, Switzerland). Four measurement items were thoracic vertebrae (Th1–Th12), lower thoracic vertebrae (Th9–Th12), lumbar vertebrae (Th12–S1), and sacral slope.