Melatonin levels in idiopathic scoliosis: Diurnal and nocturnal serum melatonin levels in girls with adolescent idiopathic scoliosis

Study Design. Matched pairs of adolescent girls were used to compare serum melatonin levels in adolescent patients and control subjects with idiopathic scoliosis during the day and in the middle of the night. Objectives. To compare serum melatonin levels in patients with adolescent idiopathic scoliosis and matched control subjects during the day and in the middle of the night. Summary of Background Data. Recent studies using the chick as the animal model have suggested that the pineal gland and its main product, melatonin, might be involved in the cause of scoliosis. There have been no studies of melatonin levels in patients with adolescent idiopathic scoliosis. Methods. Blood was collected from seven adolescent girls with idiopathic scoliosis and a group of seven age-matched control subjects. Two samples were collected, one in the middle of the day and one in the middle of the night, to examine the diurnal variation of melatonin production. Serum melatonin levels were measured using a radioimmunoassay technique. Results. No significant differences were found in serum melatonin levels between experimental and control groups either during the day, when melatonin levels were low, or during the night, when melatonin levels were high. Conclusions. Whereas pinealectomy in young chickens leads to reduced melatonin levels and the development of scoliosis, the results of this study suggest that melatonin levels in mature patients who already have severe scoliosis do not differ from healthy subjects. Whether melatonin levels differ in humans between healthy subjects end patients with scoliosis at the time of onset of the disease remains to be seen.