NATURAL COURSE OF EXPERIMENTAL SCOLIOSIS IN PINEALECTOMIZED CHICKENS

Study Design. Pinealectomy induces experimental scoliosis in chickens. This study analyzed the natural course and characteristics of the sco liosis that developed after pinealectomy. Objectives. To investigate t he natural course of experimental scoliosis after pinealectomy in chic kens and determine its similarity to idiopathic scoliosis in humans. S ummary of Background Data. Pinealectomy affects the systemic hormonal balance and consistently induces progressive scoliosis in chickens. Me thods. Thirty-five chickens were divided into two groups, a pinealecto my group (n = 25) and a control group (0 = 10). At the age of 3 days, all chickens in the pinealectomy group underwent surgery. Spinal radio graphs of all chickens were taken at 2-week intervals until the age of 16 weeks. Results. There was no alteration of spinal alignment in the control group. Seventeen chickens in the pinealectomy group had scoli osis (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, o r severe as the chickens grew older. Pinealectomized chickens showed s everal other differences from chickens of the normal control group, su ch as poor weight gain, underdeveloped cockscombs, and late onset of e gg laying. Conclusions. The scoliosis developing in chickens after pin ealectomy was similar to human idiopathic scoliosis, and thus seems to be a useful model of idiopathic scoliosis.