Brief overview
- Symptoms: Acute general signs of inflammation such as fever, redness, or swelling, usually localized pain of the affected body part
- Prognosis and course of disease: With rapid and consistent treatment, acute inflammation curable, transition to chronic form possible, without medical treatment risk of life-threatening blood poisoning
- Causes and risk factors: Mostly caused by bacteria, risk depends on: Age, operations, concomitant diseases, etc.
- Diagnosis: Medical consultation, physical examination, inflammation values in the blood, magnetic resonance tomography, computer tomography, X-ray, ultrasound
- Treatment: immobilization, antibiotics, surgical cleaning of the inflammation
What is bone inflammation?
Osteitis and osteomyelitis are caused in most cases by bacteria and only very rarely by viruses or fungi. Most frequently, osteomyelitis occurs after bone surgery. Other triggers are bone fractures or infections. For reasons that are not yet clear, men are affected more often than women.
Most often, the bones of the legs are inflamed, especially the upper or lower leg bones. A special form of bone inflammation is the so-called spondylitis, in which the bones of the spine (vertebral bodies) are inflamed. This inflammation occurs mainly in adults.
What are the symptoms of osteitis?
The symptoms of osteitis (bone inflammation) and osteomyelitis (bone marrow inflammation) often depend on how the inflammation develops.
If the bone inflammation occurs acutely, typical signs of inflammation often appear. These include:
- General fatigue
- Fever and chills
- Pain
- swelling and overheating, sometimes redness of the affected part of the body
Acute osteomyelitis is usually caused by bacteria that infect the bone through the bloodstream. Doctors then refer to this as acute hematogenous osteomyelitis.
If it is the chronic form of bone inflammation (osteitis), the symptoms are often less typical of inflammation. The pain is usually dull and there are few general complaints. In addition, there are always long symptom-free intervals. However, if the bone inflammation breaks out again, all the symptoms of an acute infection may reappear with each outbreak.
In chronic bone inflammation, the body may try to fight the bacteria itself by forming a kind of capsule around the inflamed area. Inside this capsule, however, the bacteria continue to live. This causes pain and restricted movement in the affected joint. From time to time, the inside of the capsule empties outward in the form of pus.
What are the risks of bone inflammation?
The risks and chances of recovery from bone marrow inflammation (osteomyelitis) or bone inflammation (osteitis) depend on the type of inflammation, the age of the person affected, the strength of his immune system and the type of pathogen involved. Basically, the disease requires medical care. Otherwise, there is a risk of permanent damage to the affected parts of the body and a risk of blood poisoning (sepsis). Sepsis may be life-threatening.
Acute bone marrow inflammation has a good chance of recovery, provided prompt medical treatment. The chances of recovery in children with bone marrow inflammation are generally better than in adults. Bone inflammation can also usually be cured without permanent damage if a doctor detects and treats it in time.
In children, on the other hand, there is a risk of growth disturbance if the osteomyelitis affects the growth plates of the bones. In children, the growth plates are still made of cartilage and ensure healthy growth in size by constantly building up new bone substance. If something disturbs this process, in some cases this leads to short stature and shortened arms and legs – depending on where the focus of the inflammation is located.
How does bone inflammation develop?
Bone inflammation occurs when bacteria reach the bone from the outside, for example in the case of an open injury or a surgical wound. Exactly which bones are affected depends on the location of the causative injury. Bone marrow inflammation also occurs when bacteria enter the bone through the bloodstream (hematogenous).
Types of development of bone inflammation
Hematogenous (endogenous) bone inflammation: When bacteria enter the bone through the bloodstream, there is a possibility that they will cause inflammation in the bone. In this case, bone marrow inflammation occurs because this tissue is riddled with blood vessels.
Basically, any bacterial infection has the potential to cause hematogenous osteomyelitis. Even if the bacteria originally come from, for example, otitis media or jaw inflammation. Jaw inflammation occurs, for example, as a complication when the dentist or oral surgeon extracts a severely inflamed tooth.
Posttraumatic (exogenous) bone inflammation: In this type of development, bacteria reach the bone from the outside and locally, for example via an open accident wound, especially if bone is exposed. Infections of a surgical wound that occur during or after surgery are also included here.
Among other things, bone infections occur at the edge of screws or plates that are inserted into the bone during surgery. One reason for this is that the immune defense does not work properly at these sites. Bacteria therefore multiply undisturbed here, sometimes resulting in bone inflammation.
Pathogens of bone inflammation
Regardless of how the inflammation develops, many pathogens have the potential to cause bone inflammation:
- The most common (75-80 percent) is the bacterial pathogen Staphylococcus aureus (in both children and adults)
- Other common bacteria include group A streptococcus and pneumococcus
Risk factors for bone inflammation
The following risk factors are among those that increase the risk of developing bone inflammation after an injury or surgery:
- Low age: growth plate is well supplied with blood
- Advanced age: bone blood supply is reduced
- Concomitant diseases: Diabetes mellitus and/or peripheral arterial disease (pAVK)
- Immunodeficiency: Due to diseases such as HIV or immunosuppression
- Sickle cell disease
- Kidney and/or liver weakness
- Nicotine, alcohol and drug use
How is bone inflammation diagnosed?
- Have you suffered from increased symptoms of illness such as fever or dullness in the past few days?
- Have you had surgery in the past few days or weeks?
- Exactly where are the aches and pains?
After the medical history, a physical examination takes place. First, the doctor palpates those bones or joints that hurt. If a pressure pain occurs or a clear swelling or redness is visible, this is a further indication of bone inflammation.
In addition, the doctor takes blood and has a blood count done. An elevated level of white blood cells (leukocytes) and an elevated level of C-reactive protein (CRP) indicate inflammation in the body.
If a joint is particularly swollen, the doctor sometimes uses a slightly thicker needle to perform a joint puncture. This involves taking a sample of the joint fluid, which a laboratory then checks for certain bacteria.
The physician uses an ultrasound examination to determine whether additional soft tissues (for example, muscles) are affected by the inflammation or whether there is joint effusion.
Brodie abscess
A special form of bone inflammation in childhood is Brodie’s abscess. In this case, a painful swelling occurs in a specific demarcated area. Laboratory findings are usually unremarkable and symptoms are less pronounced. However, radiographs show that the periosteum is detached from the bone (periosteum). MRI also shows changes in the bone structure.
How is bone inflammation treated?
To treat bone inflammation effectively, it is therefore important to eliminate the bacteria that cause it. For this purpose, the affected person receives antibiotic therapy. For a targeted therapy, doctors try to determine the pathogen by means of a tissue sample. Ideally, this is done before the first administration of the antibiotic. If antibiotic therapy is unsuccessful even after switching to other antibiotics, surgical cleaning of the wound is necessary.
In general, doctors recommend immobilization of the affected part of the body for at least a week, especially in the acute forms, and even longer in the case of inflammation of the spine. To prevent thrombosis due to immobilization, patients are usually given physiotherapy with passive exercise therapy and blood-thinning medication.
Therapy of hematogenous acute osteomyelitis
In acute bone marrow inflammation (osteomyelitis), caused by pathogens in the blood, physicians usually prescribe antibiotic administration via the vein by infusion, more rarely in tablet form. The antibiotics reach the bone marrow via the bloodstream, where they kill the bacteria. This therapy is usually administered over several weeks, initially in hospital.
It is crucial for a good cure that hematogenous osteomyelitis is recognized and treated at an early stage. In children, the disease is often diagnosed too late because it is unclear for a long time where the symptoms originate. This increases the risk of sepsis. To prevent this, doctors refer children in particular to hospital immediately whenever there is a reasonable suspicion of hematogenous osteomyelitis.
Therapy of post-traumatic acute osteomyelitis:
If osteomyelitis occurs after an injury or surgery, antibiotic therapy alone usually does not lead to healing. The injured tissue is too poorly perfused for this. Typically, symptoms appear here three to five days after the injury or surgery. Doctors usually then open the wound (again) and operate on it (again).
During surgery, doctors then remove a tissue sample for targeted antibiotic therapy, remove foreign bodies, stabilize the bone, irrigate the wound and sometimes place local antibiotic carriers in the wound. This is followed by antibiotic therapy again for several weeks.
Therapy of chronic osteomyelitis:
If bone structures are already damaged or if the inflammation continues to progress despite antibiotic therapy, the affected bone tissue is usually removed by surgery. Artificial implants replace the removed parts of the bone so that it is stable again after healing. If there are foreign bodies such as plates or screws in the affected bone and there is a risk that they will prevent or complicate healing, the surgeons remove these as well.
After surgery, there are several treatment options to choose from. If joints are affected by the bone inflammation, doctors often use small sponges containing antibiotics. In addition, they usually place a drainage tube to the outside, through which wound secretions drain out of the joint.
In some cases of bone inflammation, a single operation is not sufficient. Doctors then operate on the affected area again – either to remove further inflamed tissue or to reinsert previously removed support structures or implants. Even if there are no symptoms for a long time, there is a risk that a new focus of inflammation will form years after the initial surgery (recurrence).
Complications of the surgery
As with any surgical procedure, there are certain risks associated with surgery for bone inflammation. During and after surgery, there may be bleeding, secondary bleeding, and bruising due to injury to blood vessels in the opened area of the body. In addition, there is sometimes a risk of re-infection or sensory disturbances due to injury to nerves in the surgical area.
