There is no cure for brittle bone disorder (osteogenesis imperfecta), but there are some management options.
What is Osteogenesis Imperfecta?
A congenital disease, caused by a defective gene, osteogenesis imperfecta (OI) makes brittle, or fragile, bones. Type 1 collagen, which is a necessary component of bone building, is deficient during development. Sometimes OI is caused by a spontaneous genetic mutation, but most cases are inherited. In general, the hallmark symptoms of OI are blue sclera (a blue tint in the white part of the eyes), bone fractures, and hearing loss or deafness. Most people with the brittle bone disorder are short in height and can have poor teeth. Ligaments also have type 1 collagen, so OI patients may also have flat feet and hypermobility, or loose joints. More severe cases of OI can display scoliosis, kyphosis, or bowed limbs. Type I OI is mild, and patients can live a more normal life. Type II is severe, and death often occurs within the first year of life. Type III is also severe, and it presents with bone deformities and multiple fractures. These patients generally end up in a wheelchair, with a shortened life. Type IV is moderately severe, with patients needing braces and crutches to walk; like Type I, a normal lifespan is expected. Because bones are weakened, deafness, heart failure, spinal cord problems, respiratory issues, and deformity are complications of osteogenesis imperfecta.1 There are other types of OI, ranging from V-VIII as well. Another name for OI is Lobstein syndrome. OI occurs in about 1 out of 20,000 live births. There is no single way to test for OI, but it must be differentiated from child abuse, rickets, and other skeletal problems.2 OI patients may also bruise more easily and develop hernias.3 One famous actor with osteogenesis imperfecta is Atticus Shaffer, known for playing Brick on TV’s The Middle. His mother has Type I OI, and he has Type IV.4
Prognosis and Treatments
There is no cure for OI. Some medications, like bisphosphonates for osteoporosis, can help with bone strength and density. If used early, such as in children, they can reduce fractures and bone pain, especially in the spine. Swimming and low impact exercises that build muscles can help with bone maintenance. Some patients may need surgery, such as putting metal rods into the leg bones, or reconstructive surgery for spinal problems or bowed legs, to increase mobility. Fractures will continue to occur in OI, but it is still important for patients to limit their time in casts. Disuse osteoporosis is a risk, where bone loss occurs from the lack of use of the fractured body part.5 Bone infections are also possible in OI, and antiseptics and antibiotics treat those. Wheelchairs, splints, crutches, and other devices are often necessary to help patients maintain some autonomy. Useful ways to strengthen muscles and improve mobility include hydrotherapy and physiotherapy. The latter is more helpful to adults, as children tend to want to avoid movement that causes pain.6 All OI patients should avoid smoking, which has a negative impact on bones. Menopausal women may benefit from taking hormone replacement therapy (HRT).7