The idiopathic juvenile osteoporosis.

Idiopathic juvenile osteoporosis (IJO) is a rare primary form of osteoporosis of unknown etiology that develops in a previously healthy child. IJO is characterized by repeated fractures, including vertebral compression fractures. It is usually a self-limiting disease that spontaneously resolves after puberty, but in some cases it may result in severe deformities and functional impairment. There are probably the following reasons about etiological factors and pathogenesis in IJO: 1) Imbalance between bone formation and bone resorption; 2) Adolescent growth burst and bone mass increase; 3) Abnormal metabolic regulation factors of bone; 4) Abnormal collagen synthesis. IJO runs an acute course, usually over a period of 2 to 4 years, during which time there is growth arrest and multiple fractures, and then the disease remits. Both the axial and the appendicular skeleton are affected. The severe cases may have fractures of the vertebrae and the long bones, particularly in the metaphyses, that lead to pain in the back, foot, hip and extremities, muscle weakness, limitation of free movement, deformity, and unique gait because of difficulty in walking. The diagnosis of IJO is based both on the exclusion of other diseases and on its own positive features. The diagnosis of IJO is best made from its X-ray features, which include multiple vertebral compression fractures and fractures of the long bones, especially around the weight-bearing joints. Treatment of IJO is extremely complicated. The basic strategy of treatment is to protect the spine and to avoid the occurring of fractures and deformity until remission occurs. Supportive care is instituted promptly in anticipation of spontaneous recovery with the onset of puberty. [ABSTRACT FROM AUTHOR]