Osteosclerosis describes a hardening of the bones due to various causes. This leads to an excessive increase in bone substance. However, the stability of the bones is impaired.


What is osteosclerosis?

Osteosclerosis is not a single disease. The term only describes the changes in the bones in the direction of hardening and increase in bone mass. Despite significant bone density, the bone architecture is not stable. There are frequent fractures and, depending on the underlying disease, further ossification. See theinternetfaqs for Metabolic Syndrome Basics.

There are both genetic causes of osteosclerosis and secondary hardening of the bones due to an underlying disease. In most cases, osteosclerosis is generalized. That is, the entire skeleton is affected by the disease process. But there are also cases with local osteosclerosis. Especially with the primary form of bone hardening, a genetic defect can almost always be assumed to be the cause.

This form of the disease is very rare. Secondary osteosclerosis is more common and occurs particularly in renal insufficiency. But there is also a form with increased intake of fluorides through food. This form also belongs to secondary osteosclerosis. Localized forms of osteosclerosis can result from malignant or benign bone tumors or as part of Paget’s disease.


There are several causes for the development of osteosclerosis. Bone hardening is part of the outward appearance of the symptom, with bone mass steadily increasing but bone stability decreasing. The hardening of the bone can take place on the basis of the increase in the inorganic material, the organic component, or both components. In some cases, complicated and uneven conversion processes occur.

In other cases, only bone formation takes place without remodeling processes. For example, in the case of hereditary osteopetrosis (marble bone disease), the bone is only built up without any degradation processes occurring. As a rule, the precursors of bone cells consist of osteoblasts and osteoclasts. Osteoblasts build bone while osteoclasts break down excess bone material.

A constant remodeling process has to take place within the bones in order to constantly remodel the bones. However, this is not the case with osteopetrosis. Another hereditary form of osteosclerosis is Engelmann syndrome. This leads to irregular bone growth with increasing bone hardening and loss of stability of the bones.

In the case of melorheostosis, the bone metabolism is undisturbed, but the irregular growth in some places, especially on the extremities, leads to thickening of the bones. It looks like the bones are flowing. This disease is also caused by a genetic defect. Secondary osteosclerosis develops more frequently as part of renal insufficiency.

The disease known as renal osteodystrophy is a very complex bone growth disorder. Kidney failure causes the vitamin D hormone metabolism to be disrupted. Calcium and phosphate are no longer retained and are increasingly excreted. The resulting hypocalcemia increases the concentration of parathyroid hormone, which in turn leads to bone demineralization. To compensate for the demineralization, more connective tissue-like bone material forms. Bone mass increases. At the same time, however, there is a loss of stability.

Symptoms, Ailments & Signs

The progression of the individual diseases varies. A common symptom, however, is a constant increase in bone mass and at the same time a reduction in bone stability. The accompanying symptoms depend on the underlying disease. Osteopetrosis is characterized, for example, by increased bone fragility, liver and spleen enlargement, immune deficiency, cramps and cranial nerve damage.

There are also diseases that are characterized by multiple dysplasias in addition to osteosclerosis, such as the genetic Lenz-Majewski syndrome. Secondary renal osteodystrophy is characterized by bone and joint pain and swelling. Bone fragility is increased. At the same time, muscle atrophy also occurs. External calcium deposits can be found on the joints in the area of ​​elbows, shoulder joints, knees, toes or finger joints.

These are deposited again at the edges of the bones as a result of increased lime dissolution processes within the bones. This causes pain, which severely limits mobility. Calcium deposits can also form in the arteries, causing arterial occlusive disease with all its consequences.

Diagnosis & course of disease

The diagnosis of osteosclerosis is heavily dependent on the underlying disease or disorder. If a severe kidney disease is identified, the character of the disease is examined diagnostically in the overall context. If a hereditary disease is suspected, human genetic tests can be carried out. However, this requires an intensive anamnesis of the family medical history. If there is local osteosclerosis, the direction of the tumor should also be examined.


Osteosclerosis patients suffer from reduced bone stability. Even minor injuries often result in broken bones or other bone injuries. For this reason, patients with osteosclerosis must definitely avoid accidents and impacts, as bone healing is also impaired.

Furthermore, it is not uncommon for those affected to have a significantly weakened immune system and muscle cramps. The liver and spleen are significantly enlarged, so pain can occur in these regions. Furthermore, the weakened immune system leads to more frequent infections and inflammations. Without treatment, it can also lead to brain damage, which is usually irreversible and should be avoided at all costs.

Furthermore, there are complaints in the joints and arterial occlusion can occur. As a rule, a causal treatment of osteosclerosis takes place. There are no special compilations, but a tumor may have to be removed. Furthermore, the patients need chemotherapy, which usually takes place with side effects.

When should you go to the doctor?

If there is pain in the bones or problems moving the hands and feet, a doctor should be consulted. The symptoms indicate osteosclerosis, which must be clarified quickly in order to avoid an increase in symptoms and long-term consequences. Those affected should consult a doctor if the symptoms mentioned do not go away on their own or if they increase in intensity within a short period of time. At the latest when the typical joint noises are added, medical advice is required.

The doctor can quickly identify the osteosclerosis using imaging methods and anamnesis and, if necessary, initiate treatment directly or refer the patient to a specialist. People who have already had a bone infection or inflammation of the bone belong to the risk groups. You should consult with the doctor responsible if the symptoms described appear and do not go away on their own. Close medical supervision is also necessary after bone injuries, contact with toxic substances and bone cancer. In addition to the general practitioner, the orthopedist canor consult a specialist in internal medicine. In cooperation with nutritionists and genetic counseling centers, the cause of osteosclerosis can be determined. During therapy, physiotherapists, sports physicians and other specialists are involved in the treatment.

Treatment & Therapy

The treatment of an existing osteosclerosis depends on the cause. Hereditary diseases cannot be treated causally. Only symptomatic treatments are possible here. This includes constant monitoring and also the treatment of any fracture that may have occurred. If a tumor is diagnosed, surgical measures are of course necessary.

If the tumor is malignant, chemotherapy and radiotherapy follow. Renal osteodystrophy can only be treated as part of the overall therapy for the kidney disease. If it turns out that fluorosis is present, stopping the heavy fluoride intake is sufficient.

Outlook & Forecast

The prognosis of osteosclerosis is based on the stage at which the disease is recognized and treated and what form of osteosclerosis it is. If the condition is left untreated, ossification can increase and cause various health problems over the course of life. First of all, the resilience of the bones is reduced, which means that the patient has to accept various restrictions. There is no prospect of a full recovery. Existing hardening of the bone tissue can only be reduced by complex procedures. The orthopedic specialist makes the prognosis. Depending on the form and severity of the disease, he may involve other doctors.

Since osteosclerosis develops in phases and the cause cannot usually be treated, the prognosis must be regularly adjusted to the current state of health of the patient. Thanks to modern medicine, the prospect of a symptom-free life is relatively high. Life expectancy is usually not limited by osteosclerosis. However, there is an increased risk of obesity, cardiovascular problems and falls. In the secondary form of osteosclerosis, there are also serious underlying diseases such as cancer or kidney disease, which can reduce quality of life and life expectancy.


A general recommendation for the prevention of osteosclerosis cannot be given. The causes are very diverse and rarely dependent on lifestyle. Normal fluoride intake should only be ensured to prevent fluorosis.


In most cases, those affected by osteosclerosis have only very few and usually only limited direct follow-up measures available. For this reason, sufferers of this disease should consult a doctor very early on in order to prevent the occurrence of further complications and symptoms. It cannot heal on its own, so those affected should always consult a doctor.

Most of those affected are usually dependent on a surgical procedure, through which the tumor can be removed. The earlier this intervention takes place, the better the further course. After such an operation, the person concerned should definitely rest and rest, avoiding exertion or stressful and physical activities.

Most patients also depend on the support and help of their own families during treatment. Loving and intensive conversations also have a positive effect on the further course of osteosclerosis and thus also prevent mental upsets or depression. In some cases, osteosclerosis also reduces the life expectancy of the person affected.

You can do that yourself

People who have been diagnosed with osteosclerosis can take some actions to speed up recovery and make living with the condition easier.

First of all, however, it is important to comply with the doctor’s instructions regarding diet and physical activity. Patients should work with a nutritionist to create a diet and follow it consistently. Although this cannot remedy the bone disease, an individually adapted diet reduces the pain and increases the well-being of those affected. The same applies to sport and a regular daily routine with sufficient sleep and little stress. Any movement restrictions must be compensated for by aids such as walking aids or prostheses. Patients should consult a specialist at an early stage and take the necessary steps. In addition, constant monitoring and treatment of any fractures is necessary in any case.

If the osteosclerosis is caused by a malignant tumor, chemotherapy or radiotherapy is indicated. This can be supported by those affected by rest and physiotherapy. If fluorosis is the cause, it is sufficient to discontinue the triggering food or medication and to rest the body for a few weeks.