View Full Version : dogs and scoliosis

10-20-2006, 02:40 PM
really do not know what the practical relevance is of this study, still, it is interesting, specially the comments it makes about pre-existing rotation of the spine in non scoliotic spines, did not know that

Analysis of Preexistent Vertebral Rotation in the Normal Quadruped Spine.


Spine. 31(20):E754-E758, September 15, 2006.
Kouwenhoven, Jan-Willem M. MD *; Vincken, Koen L. PhD +; Bartels, Lambertus W. PhD +; Meij, Bjorn P. DVM, PhD ++; Oner, F Cumhur MD, PhD *; Castelein, Rene M. MD, PhD *
Study Design. In this CT study, vertebral rotation was analyzed in the transverse plane of the normal, nonscoliotic canine spine with a computer-based measurement method.

Objectives. To determine if a rotational pattern exists in the normal, nonscoliotic quadruped spine, similar to what is seen in humans.

Summary of Background Data. Idiopathic scoliosis does not occur in quadrupeds. In humans, the normal, nonscoliotic spine shows a preexistent pattern of vertebral rotation, which corresponds to the most prevalent curve types of idiopathic scoliosis. Since this rotational tendency has only been demonstrated in humans, it is not clear if it can be considered as a part of the pathogenesis of idiopathic scoliosis or as a normal anatomic feature.

Methods. CT scans of the thorax of 42 dogs without clinical or radiologic evidence of scoliosis were used to measure axial vertebral rotation from T1-T13 with a previously developed computer-based CT measurement method.

Results. The results of this study demonstrated a predominant rotation to the right of the upper, mid, and lower thoracic vertebrae of the normal canine spine. The mean vertebral rotation angles differed significantly from zero degrees rotation at level T1, from level T4-T7, and from T11-T13.

Conclusions. The normal spine of quadrupeds shows rotation of the thoracic vertebrae with a preferred direction to the right, similar to what is seen in humans. Since idiopathic scoliosis does not exist in quadrupeds, this preexistent rotation seems to be a physiologic process in normal spinal development, independent of the pathogenesis of scoliosis.

03-23-2007, 12:48 PM
did anybody know about this pre existent rotation of the spine and its relevance??

03-23-2007, 09:41 PM
That's pretty interesting Gerbo... I have no idea what it's relevance may be. It does make me wonder if the right rotation is caused by the fact that the stomach is suspended primarily from the left side of the torso/spine. Might the constant eating/additional weight in the stomach exert a pulling force downward on the left side of the spine/ribs thus drawing it into a right rotation???? I don't know.... that would be my only mechanical explanation, aside from genetic morphological factors.

Since idiopathic scoliosis does not exist in quadrupeds, ...I didn't know this... it makes me wonder if the quadruped's horizontal spine orientation relative to gravity has anything to do with this. Lateral deviations in a quadrupeds spine would be relatively unaffected by gravity, ...sideways motion could not be influenced by this downward force, but in humans with a vertical orientation it can be/is heavily influenced by gravity.

Interesting study.... gets me thinking...