New uses of bisphosphonates: osteogenesis imperfecta.

Osteogenesis imperfecta is a heterogeneous group of inherited disorders chiefly affecting type I collagen, resulting in bone fragility responsible for a host of recurrent fractures. Limb and spine deformities, growth failure and restricted mobility are the end-result in severe cases. Cyclical intermittent intravenous infusions of pamidronate, a potent inhibitor of bone resorption, have yielded substantial improvement in chronic pain, bone mineral density, fracture rate and mobility without significant side effects. The role of growth hormone and bone marrow transplantation in the treatment of osteogenesis imperfecta is still unresolved. Newer, theoretically more potent bisphosphonates are currently being tested in this potentially crippling condition.