Osteogenesis imperfecta--multi-systemic and life-long disease that affects whole family

Osteogenesis imperfecta or brittle bone disease, a heritable disorder of connective tissue, is the most common of the inherited disorders primarily affecting bone. There are approximately 400 individuals with OI in Croatia alone. It is estimated that twice that number is present, represented by individuals with mild OI in whom the diagnosis has not been made. Due to the relatively low number of patients in the general population, treating physicians have limited experience with this disease, either with children or adults. The basis of this disease in European populations is mostly the result of defects in the structure or processing of collagen type I, an important protein of the extracellular matrix of many tissues. Presently, molecular defects in 16 different genes have been discovered to result in at least one type of OI of which 14 are not COL1 mutation loci. Although fractures occurring with no injury or minor injury are the hallmark of OI, other non-mineralized tissues can be affected as well and the pathological changes can be present in skin, tendons, eyes, teeth and blood vessels. Clinical manifestations are very heterogeneous and numerous signs and symptoms such as blue sclera, deafness, abnormal teeth development, joint hypermobility, increased risk of hernias, capillary fragility, aneurysms etc. Although there is no cure for this disease, there are specific therapies that can reduce the pain and complications associated with OI. The purpose of this review is to provide a brief overview of the molecular basis of this disease, describe clinical presentations, as well as to present orthopaedic therapeutic modalities for the patients with OI.