Children with rickets may come to medical attention because of specific physical abnormalities (bowed legs), limb pain and swelling, seizures, failure to thrive (renal tubular acidosis), biochemical abnormalities (hypocalcemia), radiographic findings (broadened, frayed metaphysis), or during the evaluation of a fracture Triage Rickets should be considered in patients with nonspecific bony complaints Initial Assessment/H&P A thorough social and dietary history is helpful in delineating the probable cause of the rickets and in sparing the patient an extensive and expensive evaluation A family history may be useful in identifying the 1-alpha-hydroxylase deficiency or renal phosphate wasting If the child has previously been treated with vitamin D, the reported response to that treatment may be helpful in identifying the likely site of defect The clinical findings in rickets may vary considerably, depending on the underlying disorder, the duration of the problem, and the child’s age Most features are related to skeletal deformity, skeletal pain, slippage of epiphyses, bony fractures, and growth disturbances Muscular weakness, hypotonia, and lethargy are often noted FIGURE 89.4 Rickets in an 11-month-old boy, breast-fed since birth A : Roentgenogram of the upper extremity shows profound demineralization of the skeleton, with frayed, irregular cupping of the end of the metaphysis and poorly defined cortex Note retardation of skeletal maturation B : Same patient with some healing weeks after supplemental vitamin D Severe rachitic changes are noticeable Periosteal cloaking, both of the metacarpals and of the radius and ulna, is evidence of healing C : Complete healing of the rickets months after treatment Note the reappearance of the provisional zone of calcification (Courtesy of Soroosh Mahboubi, MD, The Children’s Hospital of Philadelphia.) Failure of calcification affects those parts of the skeleton that are growing most rapidly or that are under stress For example, the skull grows rapidly in the perinatal period; therefore, craniotabes is a manifestation of congenital rickets However, the upper limbs and rib cage grow rapidly during the first year of life, and abnormalities at these sites are more common at this age (i.e., rachitic rosary, flaring of the wrist) Bowing of the legs is unlikely to be noted until the child is ambulatory Dental eruption may be delayed, and enamel defects are common Management/Diagnostic Testing Radiography is the optimal way to confirm the clinical diagnosis of rickets because the radiologic features reflect the histopathology Characteristic findings include widening and irregularity of the epiphyseal plates, cupped metaphyses, fractures, and bowing of the weightbearing limbs ( Figs 89.4 and 89.5 ) The clinical laboratory is often helpful in correctly identifying the cause of rickets Frank hypocalcemia (