The theory behind Orthopedic Manipulative Therapy for the spine, is that patients with more or less diminished mobility between two individual vertebrae, with pain that can be provoked upon movement at the vertebral segment, can with specific manual treatment, become symptom‐free or have their condition improved and normal mobility restored. In order to apply this therapy, the practitioner must be able to examine mobility between individual vertebrae, i.e., a specific spinal examination. The examination of intervertebral mobility is difficult, and skeptics doubt that manual assessment between individual vertebrae is reliable or even possible.
The first known inter-tester reliability study of special manual mobility tests in the spine, was conducted by Olav Lindahl and myself over 45 years ago in connection with a course we taught in manual therapy evaluation and treatment at Falsterbo, Sweden in June 1968. We investigated the reproducibility of manual mobility tests of vertebrae using a specific osteopathic method. Ten specially trained manual therapy instructors examined 13 vertebral segments in four subjects. We found good agreement in the test results of individual examiners, with a 7% error rate for all examiners and a 2.2% error rate for the most experienced 7 instructors.