Osteomyelitis is the medical term for an infection in a bone. Infections can reach a bone by traveling through the bloodstream or spreading from nearby tissue. Osteomyelitis can also begin in the bone itself if an injury exposes the bone to germs.
In children, osteomyelitis most commonly affects the long bones of the legs and upper arm, while adults are more likely to develop osteomyelitis in the bones that make up the spine (vertebrae). People who have diabetes may develop osteomyelitis in their feet if they have foot ulcers.
Once considered an incurable condition, osteomyelitis can be successfully treated today. Most people require surgery to remove parts of the bone that have died — followed by strong antibiotics, often delivered intravenously, typically for at least six weeks.
There are several different ways to develop osteomyelitis. The first is for bacteria to travel through the bloodstream (bacteremia) and spread to the bone, causing an infection. This most often occurs when the patient has an infection elsewhere in the body, such as pneumonia or a urinary tract infection, that spreads through the blood to the bone.
An open wound over a bone can lead to osteomyelitis. An open fracture where the bone punctures through the skin is also a potential cause.
A recent surgery or injection around a bone can also expose the bone to bacteria and lead to osteomyelitis.
Patients with conditions or taking medications that weaken their immune system are at a higher risk of developing osteomyelitis. These include patients with cancer, chronic steroid use, sickle cell disease, human immunodeficiency virus (HIV), diabetes, hemodialysis, intravenous drug users, and the elderly.
Symptoms of osteomyelitis can vary greatly. In children, osteomyelitis most often occurs more quickly. They develop pain or tenderness over the affected bone, and they may have difficulty or inability to use the affected limb or to bear weight or walk due to severe pain.
In adults, the symptoms often develop more gradually. Other symptoms include fever, chills, irritability, swelling or redness over the affected bone, stiffness, and nausea.
How is osteomyelitis diagnosed?
The diagnosis of osteomyelitis begins with a complete medical history and physical examination. During the medical history, the doctor may ask questions about recent infections elsewhere in the body, past medical history, medication usage, and family medical history.
The physical examination will look for areas of tenderness, redness, swelling, decreased or painful range of motion, and open sores.
Your doctor may then order various tests to help diagnose osteomyelitis. Several blood tests can be used to help determine if you have an infection in your body. These include a complete blood count (CBC), the erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and blood cultures. None of these is specific for osteomyelitis but rather they can suggest that there may be some infection in the body.
Imaging studies may be obtained of the involved bones. These can include plain radiographs (X-rays), bone scans, computed tomography (CT) scans, magnetic resonance imaging (MRIs), and ultrasounds. These imaging studies can help identify changes in the bones that occur with osteomyelitis.
After an area of bone is identified with possible osteomyelitis, a biopsy of the bone may be obtained to help determine precisely which bacteria are involved, and the culture of this can indicate the best choice for antibiotic treatment.
Treatment varies for acute and chronic osteomyelitis. Acute osteomyelitis should bc treated before a definitive diagnosis. Treatment includes administration of large doses of I.V. antibiotics (usually a penicillinase-resistant penicillin, such as nafcillin or oxacillin, or a cephalosporin) after blood cultures are taken; early surgical drainage to relieve pressure buildup and sequestrum formation; immobilization of the affected bone by plaster cast, traction, or bed rest; and supportive measures, such as administration of analgesics and I.V. fluids.
If an abscess forms, treatment includes incision and drainage, followed by a culture of the drainage. Antibiotic therapy to control infection may include administration of systemic antibiotics; intracavitary instillation of antibiotics through closed-system continuous irrigation with low intermittent suction; limited irrigation with blood drainage system with suction (Hemovac); or local application of packed, wet, antibiotic-soaked dressings.
In chronic osteomyelitis, surgery is usually required to remove dead bone and to promote drainage (saucerization). The prognosis is poor even after surgery. Patients are often in great pain and require prolonged hospitalization. Resistant chronic osteomyelitis in an arm or leg may necessitate amputation.
Some facilities also use hyperbaric oxygen to increase the activity of naturally occurring leukocytes.
Free tissue transfers and local muscle flaps are also used to fill in dead space and increase blood supply.
Special considerations and Prevention tips of Osteomyelitis:
The caregiver's major concerns are to control infection, protect the bone from injury, and offer meticulous supportive care.
- Use strict aseptic technique when changing dressings and irrigating wounds.
- If the patient is in skeletal traction for compound fractures, cover insertion points of pin tracks with small, dry dressings, and tell him not to touch the skin around the pins and wires.
- Administer I.V. fluids to maintain adequate hydration as necessary.
- Provide a diet high in protein and vitamin C.
- Assess vital signs and wound appearance daily, and monitor daily for new pain, which may indicate secondary infection.
- Carefully monitor suctioning equipment. Keep containers filled of solution being instilled. Monitor the amount of solution instilled and suctioned.
- Support the affected limb with firm pillows. Keep the limb level with the body; don't let it sag.
- Provide good skin care. Turn the patient gently every 2 hours and watch for signs of developing pressure ulcers.
- Provide good cast care. Support the cast with firm pillows and "petal" the edges with pieces of adhesive tape or moleskin to smooth rough edges.
- Check circulation and drainage. If a wet spot appears on the cast, circle it with a marking pen and note the time of appearance (on the cast). Be aware of how much drainage is expected. Check the circled spot at least every 4 hours. Watch for any enlargement.
- Protect the patient from mishaps, such as jerky movements and falls, which may threaten bone integrity.
- Be alert for sudden pain, crepitus, or deformity. Watch for any sudden malposition of the limb, which may indicate fracture.
- Provide emotional support and appropriate diversions.
- Stress the need for follow-up examinations.
- Instruct the patient to seek prompt treatment for possible sources of recurrence-blisters, boils, styes, and impetigo.