Attitudes adopted to relieve pain, such as that caused by sciatica, sacro-iliac or hip disease, in which the weight of the body is transferred to the normal side, cause a scoliosis similar to that due to irregularity in the length of the lower extremities, and is similarly made to disappear when the patient sits upon a flat surface.
Malformation or disease of the vertebræ themselves is a well recognised cause of scoliosis; the best known, as it may be also the most severe and the most intractable, is that due to rickets, under which heading it has already been described ([Fig. 225]). In a few cases a rudimentary wedge-shaped vertebra has been revealed by the X-rays.
Fig. 225.—Rickety Scoliosis in a child æt. 2.
In all of these forms or types of scoliosis the primary cause must be searched for and when found is made the first object of treatment; the treatment of the scoliosis as such is on the same lines as in the postural variety that now falls to be described.
Habitual or Postural Scoliosis.—These names have been given to the type of scoliosis that develops in young girls and for which there is no mechanical explanation.
Fig. 226.—Vertebræ from case of Scoliosis, showing alteration in shape of bones.