Abstract
Introduction Chicken studies implicate pinealectomy within a week of hatching as a cause of scoliosis. The nature of the scoliosis has been demonstrated to be similar to that of human idiopathic scoliosis. Scoliosis was not induced following pinealectomy in Rhesus monkeys (primate model). No human studies have been reported. The aim of this study is to determine if idiopathic scoliosis is associated with treatment for pineal lesions (presumably resulting in pinealectomy) in a human paediatric population.
Methods A medical records search was performed in five Australian States for pineal lesions. Identified patients underwent clinical or radiological evaluation for scoliosis. Pathology varied from germ cell tumour, germinoma, pineoblastoma, teratoma to a pineal cyst and an epidermoid cyst. Treatment ranged from biopsy/ extirpation to radiotherapy/chemotherapy.
Results Of 48 identified patients, thirteen are deceased. No scoliosis was present in the last imaging of the deceased. The mean age at presentation was 9.7 years (range 1–18 years). Ten are female. Two males have idiopathic scoliosis (4.2%). One has a 12° right upper thoracic curve (with 32° kyphosis) and the other has a 60° right thoracolumbar curve, requiring a two-stage arthrodesis
Discussion Although the incidence of idiopathic scoliosis in this cohort is greater than expected from Caucasian population studies (2–3%), it is not typical idiopathic-type, which has a female preponderance of larger deformities. New-born chicken studies demonstrate an incidence of between 50 and 100% scoliosis in the three months following pinealectomy. Chickens of both sexes are involved. Fundamental differences exist between chicken and human/primate models including the age at pinealectomy and the anatomical site of the pineal gland. Chickens have a naturally lordotic thoracic spinal curvature whilst humans/primates have a naturally kyphotic thoracic spine. Adolescents with idiopathic scoliosis have either thoracic hypokyphosis or a thoracic lordosis. Contrary to current beliefs, no causal link can be established between pineal lesions and the development of idiopathic scoliosis in a paediatric population.
The abstracts were prepared by Professor Bruce McPhee. Correspondence should be addressed to him at Orthopaedics Division, The University of Queensland, Clinical Sciences Building, Royal Brisbane & Women’s Hospital, Herston, Qld, Australia
