Growth and Skeletal System
Growth failure, which is often the first obvious sign of SIOD, occurs despite normal growth hormone production and is not corrected with growth hormone supplementation. In most affected individuals, the growth failure begins prior to and continues after birth; however, some affected children do have normal birth lengths and weights and their growth failure is not noted until after birth (range: 0 to 13 years, mean: 2 years). The heights of those who survived to adulthood were 136-157 cm for men and 98.5-143 cm for women.
The short stature arises generally because of spondyloepiphyseal dysplasia (86%), a disorder of skeletal growth; it does not arise as a complication of their renal failure. The anthropometric characteristics of patients with SIOD differ markedly from those of patients with other forms of chronic kidney disease, especially with respect to median leg length and sitting height. The spinal column and hip joint are most severely affected. The radiological abnormalities include ovoid or mildly flattened vertebral bodies, small and laterally displaced femurs (thigh bone), and shallow abnormal acetabular fossae (hip sockets). Less frequent skeletal problems include lordosis, kyphosis and scoliosis (abnormal curvatures of the spine) as well as osteopenia (decreased bone mineral density) and degenerative hip disease. Many patients have required hip replacements.
-National Organization for Rare Disorders