It is rarely possible to find if a transverse process be superior or inferior to its normal position, except the Atlas transverses, although this may occasionally be detected. Fortunately this is a rare form of subluxation, or appears rare, although it must be said that this apparent rarity may be due to our comparative inability to detect it in the living subject.
CURVES AND CURVATURES
For convenience, curve is used to denote the normal curvilinear deviation from a straight line naturally present in the normal spine or naturally assumed in response to the need for equilibrium during the erect position of the body: Curvature means either the abnormal increase of any normal curve or the appearance of any abnormal curvilinear deviation of vertebrae from their normal position. Deviations from normal must contain at least three vertebrae to be considered curvatures.
Visual Examination
The general inspection of the spine which precedes the count should bring to light, in addition to prominent subluxations, and general symptoms observable by inspection of the back, any marked curvatures. Their general locality and direction will be noted by this observation and their details left to be discovered by closer examination.
During palpation with a long and rapid glide one may also note these general points with respect to any curvature.
Do not mistake the four normal curves, the anterior Cervical and Lumbar and the posterior Dorsal and Sacral, for curvatures. The normal Lumbar curve is so unusual in practice that a novice has been known to name it a lordosis.
Description of Curvatures
Four varieties of curvature are commonly described. Kyphosis is a curvature with its convexity directed backward, usually, but not always, found in the Dorsal region. Lordosis, the opposite of Kyphosis, is an anterior curvature, usually in the Lumbar in which case it is an accentuation of the normal curve. Scoliosis has its convexity directed laterally either to the right or the left. It is commonly also Rotatory, having its vertebrae rotated around their vertical axes so as to make the outer or the inner transverses more prominent than those on the other side.
In a Scoliosis the rotation may swing either the bodies or the spinous processes toward the convex side of the curvature; the latter is much the easier of adjustment while the former furnishes one of the most intricate problems of adjustment.