Osteomyelitis is inflammation of the bone caused by an infecting organism. It is mainly caused by bacteria or other germs. Staphylococcus aureus is the most common cause of osteomyelitis.
Chronic osteomyelitis usually occurs in adults secondary to an open wound or fracture. Vertebral osteomyelitis as a result of hematogenous spread and spine surgery is also seen. Localized bone pain, erythema, and draining sinus tract are typically present. Radiographic changes are seen 2 to 3 weeks after the onset of infection and reveal osteolysis, periosteal reaction, and sequestra. Bone scan, indium scan, CT scan, MRI, and PET scans are abnormal. A specific bacterial diagnosis is made by bone biopsy, which is essential. S. aureus is the most common organism, but gram-negative bacteria are also isolated, especially if the chronic osteomyelitis occurs as a result of trauma. Therapy includes antibiotics for 6 weeks and debridement of bone.