Childhood hypophosphatasia is a form of hypophosphatasia, a rare condition that affects the bones. Symptoms vary but may include delayed motor milestones; low bone mineral density for age; early loss of baby teeth (before age 5); bone and joint pain; short stature; a waddling gait; skeletal malformations; and/or unexplained broken bones. The forms of hypophosphatasia that develop during childhood are generally more mild than those that appear in infancy. Childhood hypophosphatasia is caused by changes in the ALPL gene and can be inherited in an autosomal dominant or autosomal recessive manner.