Hansson, T. H., B. O. Roos, and A. Nachemson. “Development of Osteopenia in the Fourth Lumbar Vertebra During Prolonged Bed Rest After Operation for Scoliosis”. Acta Orthopaedica 46, no. 4 (January 1, 1975): 621–630. Accessed May 2, 2026. https://actaorthop.org/actao/article/view/29504.