Fifty-eight patients, all less than 25 years of age, underwent multilevel laminectomy for conditions that in themselves do not usually cause spinal deformity. Spinal deformity developed in 46% (12 of 26) of the patients who were less than 15 years of age, but in only 6% (two of 32) of the patients aged 15 to 24 years. Spinal deformity developed in all (100%) patients who had cervical laminectomy, in 36% of those who had thoracic laminectomy, and in none (0%) of those who had lumbar laminectomy. There was no correlation between the occurrence of deformity and sex, number of laminae removed, neurological conditions after laminectomy, or length of time after surgery.