Joints are divided into three classes and subdivided into fifteen kinds. The articulations between the bodies of vertebrae form a series of amphiathrodial joints, allowing partial movement in every direction. Those between the articular processes form a succession of arthrodial joints, having a sliding movement. Upon and within the spinal column are numerous venous plexuses. The veins within the spinal column join those on the outside through the intervertebral foramina.
Pathogenesis is the morbid process, the mode of origin, the development of disease.
To learn the cause of disease it is better to examine the living than the dead. To know of and comprehend the position of subluxated vertebrae, it is preferable to examine vertebral columns which have vertebrae displaced and ankylosed while the owner was living instead of having cuts made of vertebrae ingeneously displaced by hand to suit the fancy. Pathological means morbid or diseased. A morbid or diseased change in the tissue, bones softened and friable. Morbidity of bones, either too hard, eburnated, or too soft, friable in their texture.