Natural course of experimental scoliosis in pinealectomized chickens

Pinealectomy induces experimental scoliosis in chickens. This study analyzed the natural course and characteristics of the scoliosis that developed after pinealectomy. To investigate the natural course of experimental scoliosis after pinealectomy in chickens and determine its similarity to idiopathic scoliosis in humans. SUMMARY OF BACKGROUND DATA. Pinealectomy affects the systemic hormonal balance and consistently induces progressive scoliosis in chickens. Thirty five chickens were divided into two groups, a pinealectomy group (n = 25) and a control group (n = 10). At the age of 3 days, all chickens in the pinealectomy group underwent surgery. Spinal radiographs of all chickens were taken at 2-week intervals until the age of 16 weeks. There was no alteration of spinal alignment in the control group. Seventeen chickens in the pinealectomy group had scoliosis (17 degrees-85 degrees) that featured a three-dimensional spinal deformity consisting of both lateral curvature and vertebral rotation with rib humps. The scoliosis progressed to become slight, moderate, or severe as the chickens grew older. Pinealectomized chickens showed several other differences from chickens of the normal control group, such as poor weight gain, underdeveloped cockscombs, and late onset of egg laying. The scoliosis developing in chickens after pinealectomy was similar to human idiopathic scoliosis, and thus seems to be a useful model of idiopathic scoliosis.