Abstract
The purpose of this study was to investigate the efficacy of oral alendronate for the older children with osteogenesis imperfecta. Eight boys and 6 girls with average age of 9.7 years were given oral alendronate, 10mg everyday for those > 35kg, 10mg every other day for those 20 – 35 kg, and 10mg every three days for those < 20 kg. Treatment period averaged 3.3 years (range, 2.1 to 3.6). The number of fractures decreased by 39% in the lower extremity, although not statistically significant. Ten patients or their parents reported improved well-being during the treatment period. Z score for bone mineral density improved from −3.75 to −1.18 in the lumbar spine, and from −3.84 to −2.74 in the femur neck. Restoration of the collapsed vertebral bodies was observed, and the metaphyseal bands appeared on the simple radiographs. Urinary excretion of calcium and N-telopeptide of type I collagen were decreased by 64% and 47%, respectively. Abdominal discomfort was reported in five patients, one of which needed temporary switch to intravenous protocol. Iliac crest biopsy including the physis showed expanded primary spongiosa area with numeric multi-nucleated cells, which had heterogenous immunoreactivity for osteoclast markers.
This study revealed beneficial effects of oral alendronate in osteogenesis imperfecta patients, supported by radiological, biochemical and histological findings. We believe that oral alendronate is a more convenient method of bisphosphonate treatment for osteogenesis imperfecta, especially in older children.
Local Host: British Society for Children’s Orthopaedic Surgery. Conference Theme: Congenital Deficiencies of the Lower Limb. These abstracts were prepared by A.Catterall.
