We identified a significant association between a history of frequent fractures and hypercalcuria in children. We propose that the appropriate screening evaluation for children who present with a history of frequent fractures consists of a dietary history targeted at calcium and vitamin D intakes, a physical examination to assess for pubertal delay, and urinary calcium concentration/creatinine ratio determination to assess for hypercalcuria. Children with abnormalities in this screening should undergo dual-energy radiographic absorptiometry and appropriate evaluation.
The late Jurassic Paulchoffatiinae, one of two named subfamilies of the family Paulchoffatiidae (suborder Plagiaulacoidea), are generally recognized as the most primitive known, undoubted multituberculates (e.g., Hahn, 1969; Clemens and Kielan-Jaworowska, 1979; Hahn and Hahn, 1983; Hahn et al., 1989). Despite the primitive morphology of members of this subfamily (Paulchoffatia and Pseudobolodon), three features have been posited as autapomorphic for the subfamily (or family), and thus to preclude it from the ancestry of later multituberculates: 1) the distribution of cusps on M2 (Hahn, 1969, 1971); 2) the complex structure of I3 (Hahn, 1969, 1971); and 3) the position of M2 relative to M1 (Van Valen, 1976; Clemens and Kielan-Jaworowska, 1979; Hahn, 1987). Van Valen (1976) argued that the first two features are not unequivocally autapomorphic for paulchoffatiines and that they could, and indeed should, be considered primitive for the order. Hahn (1977) responded to Van Valen's assessment but Clemens and Kielan-Jaworowska (1979, p. 138) opined that “neither argument is particularly compelling” in light of the poor early record of multituberculates and the consequent lack of knowledge concerning morphological variability.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.