It is represented by Osteitis fibrosa, whose sole cause in uremia is secondary hyperparathyroidism. Currently observed in varying degrees depending on the series studied, the frequency and magnitude of its appearance has diminished in recent years. This is due to early drug therapy (phosphorus binders and vitamin D analogs), and mainly to ageing populations on renal replacement therapy. Mild Forms have been described, with a pattern of quantitatively lower magnitude, more frequently observed in the pre-dialysis stage, which may well be considered a previous stage of osteitis fibrosa. Moderate / Severe forms of Osteitis fibrosa present a more advanced pattern of high turnover, with abundant BRU, many active osteoclasts and osteoblasts, hyperosteoidosis and peritrabecular fibrosis. The image with double tetracycline labeling shows widely separated bands indicating a rapid rate of remodeling. Osteitis fibrosa associated with increased bone mass is relatively frequent. The classic radiological image is that showing the “rugby jersey” pattern at the vertebral level, characterized by two bands of osteocondensation separated by a lighter central band. Although forms vary depending on the series studied, the most recent show a prevalence of 10-20% for Mild forms and 20-40% for more advanced forms of Osteitis fibrosa. These percentages tend to be inverted in pre-dialysis and peritoneal dialysis patients.