Clinical and radiological features of osteogenesis imperfecta type IVA.

This paper reports a survey of 78 patients with osteogenesis imperfecta (OI) type IVA, the variant that causes the greatest difficulties in differential diagnosis. A subgroup of children aged between five and eleven were compared with a control group from local schools. Among the OI children there were, apart from the high number of fractures, also significantly increased incidences of bruising, nosebleeds, excessive sweating and hypermobility of joints. Although none of the children with OI type IV had the dark blue or grey sclerae of the type I disease, an appreciable number had pale blue sclerae in early childhood. Radiologically normal bone texture was seen at the time of the first fracture in 10 out of 17 patients. Hypertrophic callus was seen in five patients and metaphyseal fractures in four. We hope that the information on this large group of patients will assist in the prevention of diagnostic difficulties.