What is pseudarthrosis?
In pseudarthrosis, a false joint is formed. The term comes from the Greek and is composed as follows: “pseudos” means “false” and “arthros” stands for “joint”. Even if the name suggests it: Pseudarthrosis has nothing to do with osteoarthritis – the usually age-related wear and tear of the joints.
Pseudoarthrosis is always caused by a bone fracture that does not heal properly. Circulatory disorders that interfere with bone healing are often to blame. Premature stress, infections and inflammation are also possible causes. The broken bone then grows together incorrectly, resulting in a false joint.
Pseudarthrosis can affect various bones. The false joint often develops on the long tubular bones, such as the thigh, shin or upper arm. Pseudarthrosis is characterized by pain, instability and restricted mobility. If inflammatory processes also occur, redness and overheating of the affected area of the body also occur.
The treatment of pseudarthrosis is often lengthy and requires patience – on the part of both doctor and patient. The therapy often takes many months before it is sufficiently successful. Various therapies are possible, such as substances that stimulate bone formation or surgery.
Pseudarthrosis – frequency and age
Pseudarthrosis is not uncommon. Large studies have shown that pseudarthrosis can occur in a percentage of 3 to 10 percent after a bone fracture, both after conservative (without surgery) and surgical treatment of a bone fracture. In principle, pseudarthrosis can occur at any age and affect both men and women. However, bone fractures often heal less well with increasing age.
Pseudarthrosis: causes and risk factors
The cause of pseudoarthrosis is a bone fracture that does not heal properly. The long tubular bones of the femur, tibia, humerus and ulna/radius are particularly susceptible. However, the scaphoid bone – the largest carpal bone – can also be affected.
It is crucial for the healing process of a bone that it is sufficiently supplied with blood – and therefore with oxygen and nutrients. However, when a bone breaks, the surrounding tissue, periosteum and blood vessels are often also damaged. This leads to circulatory disorders, which can impair bone healing.
Other causes and risk factors of pseudarthrosis include
- The fracture was not sufficiently stabilized and compressed. Then the fractions can shift against each other.
- Too early or excessive loading of a bone fracture region. An excessive amount of new, “false” bone forms in the area of the fracture.
- Soft tissue that has got into the gap of the bone fracture.
- Open fractures in which the skin is also injured. Such fractures can become infected more easily. Bacteria and other germs then penetrate through the skin, trigger inflammation of the bone and impair bone healing. This situation is known as “infectious pseudoarthrosis”. Infections can also occur after an operation.
- older age – metabolic activity generally decreases with increasing age, which also means that bone fractures heal less well
- Smoking – reduces blood circulation and interferes with bone healing. For example, people with peripheral arterial occlusive disease (PAD, smoker’s leg, PAD) have an increased risk.
- High alcohol consumption
- Diabetes mellitus – blood circulation and bone healing can be reduced
- Overweight andobesity– they are associated with increased inflammatory activity
- Thyroid diseases
- Medication such as cortisone (anti-inflammatory agent), diclofenac (painkiller) or cytostatics (medication for cancer = chemotherapy)
- Radiation exposure
These risk factors increase the likelihood that the fracture will not heal properly.
Symptoms: Pseudarthrosis is often painful
Pseudarthrosis can manifest itself through various symptoms. The symptoms usually develop gradually. The following signs indicate that a false joint has formed:
- Pain – typically movement-dependent and load-dependent pain symptoms
- Limited mobility
- Instability of the bone
- Excessively mobile bones (hypermobility)
- Misalignments
- Functional losses
- Swelling
- Redness
- Overheating
Always consult your doctor if you experience such symptoms.
Bone fracture: How long does it take to heal?
Human bone tissue can regenerate completely if the fracture is treated by immobilization, e.g. with a plaster cast or splint, or is rejoined during an operation with the help of implants such as nails, screws, wires or plates (osteosynthesis). Most fractures heal completely within six to eight weeks and there is no subsequent loss of function. In the case of complicated fractures or unfavorable fracture locations, healing can also take longer.
Not every bone that heals slowly is a pseudarthrosis. Doctors have established the following definitions to differentiate between them:
- Delayed bone healing occurs when the bone has not healed after four to six months.
- However, doctors only speak of pseudarthrosis if the bone has not yet closed six months after the fracture.
Pseudarthrosis: Diagnosis with us
The diagnosis of pseudarthrosis always begins with a discussion of the previous medical history. The doctor treating you will ask you about your fracture, the speed of healing, previous and current treatments and the nature and intensity of the symptoms, among other things. These include, for example, pain, restricted mobility or signs of inflammation (swelling, redness). Existing pre-existing conditions also play a role, for example diabetes mellitus or circulatory disorders such as PAOD.
This is followed by a physical examination, during which the doctor palpates the body, looks for visual abnormalities and tests mobility.
In the case of pseudarthrosis, doctors also rely on imaging procedures for diagnosis. They usually show whether and to what extent the fracture has healed and whether a pseudo joint has formed. The following methods are used:
- X-ray examination – bone fractures can be made clearly visible with the help of X-rays
- Computed tomography (CT) – a method that works with X-rays and provides cross-sectional images of the inside of the body
- Ultrasound examination – sound waves are used
- Magnetic resonance imaging (MRI = magnetic resonance imaging) – it works with strong magnetic waves and also provides detailed cross-sectional images
Pseudarthrosis: Classification
Doctors can classify pseudarthrosis into the following categories based on various criteria:
- Vital (hypertrophic) pseudarthrosis: The bone and cartilage tissue is increased and well supplied with blood – the fracture is unstable, but the tissue is intact and is supplied with sufficient oxygen and nutrients. Vital pseudarthrosis is more common than the avital variant.
- Avital (atrophic) pseudarthrosis: The bone and cartilage tissue is reduced and not sufficiently supplied with blood – the poor supply to the tissue is reflected in a reduced bone structure.
Treatment also depends on the type of pseudarthrosis. The earlier it starts, the better it is for bone healing.
Pseudarthrosis: prevention, early detection, prognosis
Pseudarthrosis can have various causes. Some of these you can influence, others – such as your age – you cannot. Here are some tips that can help you prevent pseudarthrosis to a certain extent:
- Do not smoke – this can interfere with wound and bone healing. And if you are a smoker: Try to stop smoking.
- Give a broken bone enough time to heal and take it easy. Do not mobilize and put weight on the affected bone too soon. It is best to follow all your doctor’s treatment recommendations.
- Get adequate treatment for circulatory disorders. The same applies to diabetes mellitus – make sure your blood sugar levels are well controlled.
- Of course, it is best to protect yourself from a fracture right away: For example, wear appropriate protective clothing if you play risky sports or are at risk of breaking a bone at work.
Special measures for the early detection of pseudarthrosis in the doctor’s office do not yet exist. However, scientists are researching various ways of quickly recognizing defective bone healing. Some examples:
- Intelligent implants: When doctors operate on broken bones, smart implants such as nails, screws, wires or plates could be used in the future. They are equipped with microelectronics and allow conclusions to be drawn about the course of bone healing.
- Blood test to predict susceptibility to pseudoarthrosis. Doctors could then take appropriate precautionary measures as soon as a fracture occurs.
- In future, tissue samples that doctors examine in the laboratory could also provide information about the risk of pseudarthrosis and the chances of healing in the event of a bone fracture.
Otherwise, the following generally applies: Have a bone fracture checked more frequently by your doctor. He or she can recognize whether it is healing as it should. In addition, always consult your doctor if you experience symptoms such as pain, swelling or redness. Infections and inflammations may be behind it.
Course and prognosis of pseudarthrosis
The earlier the pseudo joint is discovered and treated, the more favorable the course and prognosis of pseudoarthrosis. However, treatment is often lengthy and demands a great deal from doctors and patients alike. So you have to stay on the ball and be patient and persistent.
The type of pseudarthrosis also plays a role in the course and prognosis. This means that the chances of recovery are usually good in the case of vital pseudarthrosis and the treatment is less intensive. Treatment of avital pseudarthrosis is more difficult and usually takes longer.
Pseudarthrosis: treatment depending on the type of false joint
Treatment depends on the type of pseudarthrosis. The causes also play a role in the choice of therapy.
At the Department of Traumatology at the USZ, specialists are available for people affected by pseudarthrosis, who carry out a precise examination and diagnosis and draw up an individual treatment plan together with the patient.