Fig. 2From: A retrospective analysis of bone mineral status in patients requiring spinal surgerya Prevalence of 25-OH-D deficiency and secondary hyperparathyroidism in 144 patients scheduled for spine surgery. b Levels of 25-OH-D (ng/ml) and parathyroid hormone (ng/l) in patients in dependence of daily vitamin D intake. * p < 0.05Back to article page