The spectrum of skeletal changes associated with long-term administration of 13-cis-retinoic acid.

The roentgenographic changes noted in 13 patients, who had been treated with long-term 13-cis-retinoic acid for inherited scaling disorders, are presented. These patients were aged 13-16 years and had received this therapy for 16-87 months (mean, 58 months). The most pronounced abnormality was osteophyte formation, particularly in the cervical spine. Other changes which were noted included ossification of the anterior longitudinal and atlanto-occipital ligaments, proliferative enthesopathies, diminished bone density, premature fusion of epiphyses, and modeling abnormalities. Six of the 13 patients were asymptomatic and the osseous manifestations of this therapy were identified only by roentgenographic evaluation.