AN EXPERIMENTAL-STUDY IN CHICKENS FOR THE PATHOGENESIS OF IDIOPATHIC SCOLIOSIS

Experimentally induced scoliosis was investigated in pinealectomized c hickens using pathologic and neurophysiologic means. A total of 90 chi ckens were tested; 30 served as a normal control, 30 received an autog rafted pineal body in the intramuscular tissue of the trunk, and 30 un derwent pinealectomy without autograft. Scoliosis developed in all pin ealectomized chickens within 2 weeks, showing gradual progression duri ng the next 5 or 6 weeks. At 3 months, the three-dimensional spinal de formity consisted of lateral curvature and vertebral body rotation, re sulting in a prominent lordoscoliosis at the thoracic level. In contra st, scoliosis developed in only 10% of the autografted chickens. Histo logic examination revealed no pathologic change in the brain in either the pinealectomized scoliosis group or in the autografted nonscoliosi s group. Cortical potentials in the scoliosis group were delayed, thus suggesting conduction disturbance rostral to the brain stem. Although the relationship between the cause and effect is uncertain, these fin dings implicate neurotransmitters or neurohormonal systems in the pine al body as a major contributing factor in this type of experimental sc oliosis.