Two hundred and forty-one consecutive anterior spine fusions for tuberculosis were reviewed to determine how often late progressive kyphosis occurred because of disproportionate growth of the posterior and anterior elements. Three of thirty-one patients with objective roentgenographic evidence of solid anterior fusion had an increase in kyphosis. Two of these had findings suggestive of growth retardation of the anterior ring epiphysis above the fusion mass. Posterior-element overgrowth in the third patient could not be excluded as a cause.