Peak incidence between 3 and 18 months of age
Bony pain
Generalized muscle weakness
Hypocalcemia
Growth disturbance
Enlarged and soft skull (craniotabes), long bones, joints of rib cage ("rickety rosary")
Metaphyseal hyperplasia (double malleoli sign, widening of wrist)
Bowed legs in toddlers (genu varum), knock-knees in older children (genu valgum)
Dental problems
Rickets
Hypocalcemia
Scurvy
Hyperparathyroidism
Pruritus ani
Hypophosphatemia
Porphyria
Malignancy