Osteogenesis imperfecta (OI) is referred to as vitreous bone disease because the bones of affected persons break as easily as "glass". Glasknochenkrankheit is a rare hereditary disease of which about 6, 000 people in Germany are affected. Osteogenesis imperfecta - in English "incomplete bone formation" - has as its most striking feature an increased tendency to bone fractures. Affected children therefore sometimes suffer fractures before birth.
Cause of fractures
The cause of this disease is a genetic defect in collagen metabolism. Collagen is the basic building block for all types of tissue - it provides support and stability to the bone, while keeping the connective tissue elastic. Those affected do not produce enough or only inferior collagen.
Due to the lack of collagen, the bones have too little hold. The result is that the bones can deform and break at the slightest load.
Disease course of the vitreous bone disease
Some sufferers of vitreous bone disease remember nothing of their disease until adulthood, others suffer so many fractures in their early childhood that they can never learn to walk. Often the fractures become less from puberty.
During the healing of such bone fractures, an above-average rapid and unusually high amount of bone material is formed, which can lead to deformations at the points of fracture. These deformations can severely restrict the freedom of movement of OI patients.
Professionals distinguish different severity levels:
Type 1: Bones break very fast, but grow back together normally.
Type 2: The first breaks already happen in the womb. The child rarely reaches the second year of life.
Type 3: Severe spinal deformities cause the patient to frequently sit in a wheelchair.
Glass Bone Disease: What Symptoms Are There?
The disease additionally affects all other tissues that contain connective tissue in their structure. The glassbone disease can therefore also extend to the skin, tendons, muscles, ligaments and other tissue types - it comes to weak connective tissue.
A connective tissue weakness can be recognized, for example, by stretch marks or spider veins.
Besides connective tissue weakness, other symptoms of vitreous bone disease include:
- Pulmonary and respiratory problems
- "bruises" after light bumping
- Deformation of limbs, ribcage and skull
- Scoliosis (curvature of the spine)
- conical warping of the cornea
- Laxity of the musculature
- Hyperextension of the joints
- short stature
- hardness of hearing
Diagnosis of osteogenesis imperfecta
As a rule, the diagnosis of vitreous bone disease is made by a collagen analysis of the connective tissue. On a radiograph too, a specialist can recognize "glass bones" by their almost transparent structure, which looks significantly whiter and denser in healthy people.
Prenatal ultrasound makes it possible to visualize deformed bones in the womb.
Different forms of therapy of vitreous bone disease
Since the symptoms of vitreous bone disease are very different, there is no universally valid treatment recommendation. The hereditary disease lifelong and is not yet curable. There is no causally effective therapy.
However, there are different therapeutic approaches that lead to an improvement in the life situation by stabilizing the disease state. This includes - in addition to the prevention of new fractures - the treatment with drugs that are otherwise used for osteoporosis. They are designed to increase bone density and prevent new injuries.
Active ingredients used in the treatment of osteogenesis imperfecta include:
Diet as part of the treatment
Even a balanced diet can support the therapy of vitreous bone disease.
Especially calcium and enough protein are essential for bone regeneration. For example, calcium is found particularly in kale, Emmental or Brazil nuts. High in protein are foods such as tuna and eggs.
In addition, reference is made to the sufficient intake of vitamin D, which is abundant in fish and mushrooms, for example. However, vitamin D3, which is important for bone formation, is only generated by the sun's rays on the skin.
Exercising the muscles as a supplement to the therapy
Very important in all therapeutic measures against the glass brittle disease is - as far as possible - the training of the body to build a supporting muscles. However, no further fractures should be risked.
Well suited movements are therefore swimming, aquaboxing, gymnastics and isometric exercises in which the muscles are alternately tensed and released. Unusual movements should initially be performed preferably under the supervision of physiotherapists or experienced coaches.