Types of Osteogenesis Imperfecta

Diseases of the bone affect children, teens and adults and may cause a variety of symptoms. Common forms of bone disease include osteoporosis and osteoarthritis. Another more rare bone disease, called osteogenesis imperfecta, also known as OI, meaning imperfect bone creation, creates different characteristics, symptoms and dangers, depending on severity.

Description

• Osteogenesis imperfecta is a disease that weakens bones in all areas of the body, making it very easy to break or shatter a bone. The condition affects children and adults and is relatively rare, affecting approximately 50,000 people in the U.S., according to the Osteogenesis Imperfecta Foundation. The disease is classified in types to rate varying symptoms and severity of the disease process.

Types

• Osteogenesis imperfecta, also known as OI, is classified into eight different types, each with their own characteristics. For example, Type I is considered the most common form of the disease, as well as the mildest in regard to symptoms and characteristics. With this type, there is very little bone deformity, and you may enjoy normal stature. Your bones fracture easily, though most fractures occur before you reach puberty. The most severe form of OI is Type II. This type of the disease results in growth deformities and imperfections resulting in very easily broken bones. Infants diagnosed with Type II OI can experience respiratory problems that may result in death.

  Types III through Type VIII exhibit different characteristics. You may have a barrel-shaped ribcage or a triangular-shaped face, be of short stature or experience limited range of motion in the forearm. The signs and symptoms of different types of osteogenesis imperfecta often overlap. All types of OI result in weak or brittle bones capable of fracture during even mild activities.

Signs and Symptoms

• Symptoms of the condition depend on the severity or classification of the disease. For example, Type II and Type III osteogenesis imperfecta may cause respiratory problems, easily fractured bones, curvature of the spine, brittle teeth and hearing loss. Most types of the disease also result in discolored sclera or whites of the eyes. Sclera may be gray, purple or blue. Some hearing loss is also a possibility, as are underdeveloped lungs.

Diagnosis

• Diagnosis and classification of osteogenesis imperfecta is done through DNA and molecular testing. The tests measure the amount of collagen present in the body. Collagen is a connective tissue made of protein that provides structure and support of your skeleton and joints. If you have OI, you have decreased amounts of collagen in your blood, tissues and musculoskeletal system.