Brittle bone disease or osteogenesis imperfecta is a genetic disease in which the collagen balance is disturbed and, as a result, bones break easily and become deformed. The course of brittle bone disease depends on the type of gene damage.
What is brittle bone disease?
Brittle bone disease is an inherited disorder in which collagen formation in the body is disrupted. Collagen is important for the formation of bones. However, it is also found in ligaments and tendons, in the conjunctiva of the eye, and in teeth. Osteogenesis imperfecta means “incomplete bone formation”. Normally, the bones of the human skeleton consist of collagen rods, which in turn are formed from collagen fibers, and of minerals. The two together provide both stability and elasticity to the bones. In brittle bone disease, either there is not enough collagen or the collagen fibers form abnormally shaped collagen rods. This changes the structure of the bones; they are no longer stable enough and break like glass, which has led to the colloquial name vitreous bone disease. Originally, four different types of the disease were thought to exist, but since then another three have been discovered, so that 7 types of brittle bone disease are now distinguished.
Causes
The cause of brittle bone disease is a mutation (change) in the gene responsible for the production of collagen. This gene defect causes a faulty messenger to be transmitted to the body’s cells, which then produce incomplete or altered collagen fibers. This results in deformed or broken collagen rods that are unable to provide the bone with the necessary stability. The severity of the disease depends on the extent of the defects in the collagen rods. However, there are also types of brittle bone disease in which collagen rods are produced in a completely normal shape, but their number is far too small for them to stabilize the bones. In this type of brittle bone disease, only weak symptoms are formed.
Symptoms, complaints, and signs
When it comes to the symptoms of osteogenesis imperfecta, it depends greatly on which type of the disease is present. Type 2 patients are the most severely affected, and here the disease is usually fatal at a young age. The term “brittle bone disease”, which is commonly used in the vernacular, otherwise describes the characteristic features of those affected quite accurately. Due to insufficient bone formation, bone fractures occur excessively frequently. Even slight impacts or greater stress on the bones can, under certain circumstances, result in a fracture. These fractures are then called spontaneous or fatigue fractures. As a consequence, deformations of the skull, short stature and deformations of the spine (for example scoliosis) occur. This insufficient bone formation can also be seen in X-rays. The bones allow more X-rays to pass through and the bone appears darker in the X-ray image. Doctors refer to this phenomenon as increased radiation transparency of the bones. The teeth can also be affected by the increased brittleness. The other symptoms of the hereditary disease are very complex. They include hearing loss, weak muscles and hyperextensible joints, tinnitus, myopia and increased sweating. Externally, blue sclerae may be conspicuous, especially in type 1 osteogenesis imperfecta. Sclera is the normally visible white of the eye.
Diagnosis and course
The course of brittle bone disease varies depending on the underlying type of genetic defect. The diagnosis is usually made based on symptoms and confirmed with an x-ray examination. On x-rays, healthy bone looks white, while less dense bone appears more translucent. The bending and healed old fractures that result from brittle bone disease can also be easily seen on an x-ray. The disease progresses differently depending on the type. Type 1 is most common and runs the mildest course, while type 2 is the most severe form. Affected individuals with type 2 do not have a long life expectancy and often do not survive birth. The typical symptoms of brittle bone disease are fractures and deformities of the bones. The sclerae (the sclera = the white of the eye) may be bluish, reddish or shaded gray.The physique may be largely normal as in type 1, for example, but severe spinal curvatures or short stature may also occur (type 4). Teeth are often brittle and hearing deteriorates in adolescence. Underdeveloped lungs and associated breathing problems also occur in brittle bone disease.
Complications
In osteogenesis imperfecta, there is a severe reduction in the patient’s quality of life. The daily life of the affected person is also usually associated with severe pain and restrictions. It is not uncommon for depression and other psychological upsets to occur as a result, which can be treated by a psychologist. The bones break easily and are also easily deformed. It is also not uncommon for patients to suffer from short stature and very often bruises on the skin. The spine can also be affected by osteogenesis imperfecta. Furthermore, most of those affected also suffer from respiratory problems, which can lead to a reduced oxygen supply. It is not uncommon for children in particular to become victims of bullying or teasing as a result of these complaints, which can also lead to depression or inferiority complexes. The children’s relatives and parents may also be affected by depressive moods. A causal treatment of osteogenesis imperfecta is not possible. For this reason, only the symptoms are usually limited. However, the affected person must refrain from risks and certain sports and thus suffers from severe limitations in life. The pain can also be limited with the help of therapies. This does not lead to further complications.
When should one go to the doctor?
A visit to the doctor is necessary as soon as irregularities of the physique present themselves. If there are deformities, unusual bone positions or short stature, a doctor should be consulted. Children who show little growth in direct comparison to their peers or who can overextend their joints unnaturally far should be presented to a doctor for a check-up. If visible deformities of the spine are evident, this observation should be discussed with a physician. If the bones of the affected person break very quickly, a physician is needed. If the fractures occur from even minor falls or bruises, this is considered unusual. The processes should be observed well and clarified with a doctor as soon as possible to avoid further complications. If the affected person suffers from the frequent formation of bruises or bruises, a doctor should be consulted. If there are respiratory complaints, a white eye skin, as well as a noticeable weakness of the connective tissue, a doctor is needed. If psychological problems occur with a diagnosed brittle bone disease, a doctor’s visit is also necessary. The patient needs emotional help in everyday life to cope with the disease and its consequences. Therefore, a doctor should be visited in case of behavioral abnormalities as well as changes in personality. In case of social withdrawal, a melancholic or depressive mood, as well as aggressive tendencies, a doctor must be consulted.
Treatment and therapy
Vitreous bone disease is a lifelong disorder. Because it is caused by a genetic defect, it has no cure. Affected people are advised to arrange their lives so that their bones are not subjected to additional stress or damage. This means they should eat a healthy diet, enjoy nicotine and alcohol only in moderation, and watch their weight. Even though there is no curative therapy, it is important for the further course of the disease to be detected at an early stage. If the symptoms are treated at an early stage, complications can be prevented and the symptoms at least somewhat alleviated. Currently, three treatment routes are common. One way is to administer biphosphonates. This is a substance that is deposited in the bone and inhibits the breakdown of bone material. Another treatment option for brittle bone disease is intramedullary nailing. In this procedure, metal rods are inserted inside the long bones in a surgical procedure. These act like splints, stabilizing the bones and preventing fractures and deformities. As a further treatment, physiotherapy is applied with the aim of strengthening the muscles so that they can support the bones. Mostly the training is done in water, because here there is no risk of falling and patients can move well by themselves.However, the success of treatments also depends on what type of brittle bone disease is present.
Outlook and prognosis
Affected individuals with osteogenesis imperfecta have a genetic defect. For this reason, there is no cure. Medical interventions and modern therapeutic options have significantly improved the living conditions for affected individuals. Nevertheless, many of them experience physical pain as well as psychological discomfort throughout their lives. The prognosis and course of brittle bone disease depend on the type and aggressiveness of the disease. In severe cases, life expectancy is significantly shortened. Patients with type 1 brittle bone disease usually have a good prognosis. In them, bone fractures decrease significantly after puberty, becoming more frequent again in female sufferers during menopause. For the most part, they are able to lead a regular life and hold down a job in a sedentary position. If type 2 or type 3 are present, the prognosis is much worse. Affected individuals with osteogenesis imperfecta type 3 die very early. Some of them do not survive birth and die in the womb. Due to numerous bone fractures, many affected children die within the first days of life from cerebral hemorrhages or respiratory problems. The prognosis of type 3 is unfavorable. The patients are mostly dependent on a wheelchair. Many of them develop respiratory problems.
Prevention
There is currently no way to prevent brittle bone disease because it is genetic. To avoid complications and a severe course, starting treatment early is important.
Follow-up
The aftercare of a brittle bone disease is enormously important. The affected person should take care not to lift too heavy and avoid strenuous activities. The bones are very sensitive and specific care should be taken, especially in the early stages of aftercare. It is important that the instructions of the attending physician are strictly followed. Also, medication should not be discontinued when improvement occurs. To avoid further fractures, these guidelines should be followed in any case. Light gymnastic exercises also help to strengthen the bones. In addition, swimming is a good activity to strengthen the weak body in a good way. Another important factor is taking essential vitamins and minerals. Taking vitamins such as vitamin B12, vitamin C or even zinc can support bone strengthening. The diet itself should be varied and healthy. Many sufferers do not know how important a balanced diet is for the bones and neglect it with fatal consequences. If these helpful aftercare options are adhered to by the affected person, relief from the symptoms is guaranteed to occur.
This is what you can do yourself
Brittle bone disease is a disease which is produced by a genetic defect. This disease is not curable and self-help measures are accordingly limited. Due to the very high risk of injury in patients suffering from such a disease, care must be taken to protect the body. Physical exertion is strongly discouraged. Patients must also be careful not to injure themselves in everyday life. Bumping into a piece of furniture can lead to a broken bone. Most of the time, patients need help from family members or caregivers who assist them in order to cope with everyday life. This is also important because the affected persons are often dependent on a wheelchair. The affected persons are severely restricted in their lives. This can lead to psychological problems and also to depression. Psychological treatment of patients suffering from brittle bone disease is therefore of great importance, so that the patients learn to deal with their situation. Participation in a self-help group on the subject of brittle bone disease can also act as a psychological support for those affected. The exchange with other affected people gives them the feeling that they are not alone with this situation and they can learn more about how others cope with their everyday life.
