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Begins as a phagocytic response that leads to osteolysis.
Bacteria and mycobacterium reach the bone via direct spread from traumatic injury or nearby infection or via the blood stream.
About 20% of cases are related to hematogenous spread.
More than 50% of hematogenous induced cases caused by Staphylococcus aureus.
Pseudomonas aeruginosa and Serratia species are common in intravenous drug abusers.
Most common site of acute disease is the vertebral body, a common site for tuberculosis and brucellosis.
Vertebral involvement with infection via seeding from the vertebral arteries leads to vertebral disc and adjacent vertebral involvement.
The presence of diabetes, intravenous drug use and hemodialysis increases the risk of vertebral infection.
Sickle cell anemia patients have increased susceptibility to Salmonella infections and S. aureus infections within the long bones.
Predominantly hematogenous in children and associated with blunt trauma.
In adults usual presentation with vertebral disease associated with neck, back or extremity pain.
In adults pain symptoms usually accompanied by low grade fevers over 2-3 months.
Examination in vertebral involvement reveals tenderness with vertebral percussion.
In the presence of radicular pain a spinal epidural abscess should be considered.
Chronic disease associated with fluctuating symptoms and periodic exacerbations.
With chronic vertebral osteomyelitis infection sinus tracts between bone and skin may develop with drainage of purulent material.
Most patient’s have a normal white blood cell count or a mildly elevated one.
ESR levels of greater than 100 mm/h and elevated CRP levels are common.
Only 20-30% of blood cultures with confirm the diagnosis. Osteomyelitis-early radiographs may only show soft tissue swelling, at 10 days a periosteal reaction may be present and after 2-6 weeks lytic changes may appear.
Bone lytic changes occur when 50-75% of bone density is lost.
Diagnosis confirmed by bone biopsy and culture.
Technetium-99 radio nucleotide bone scan is positive in all phases of disease and is most sensitive in the acute process.
MRI best imaging technique for detecting the presence of an epidural abscess and should be performed in all suspected cases of vertebral osteomyelitis.
To prevent bone necrosis early diagnosis and utilization of appropriate antibiotics are essential.
Requires surgical debridement and aggressive antibiotic treatment.
Erythrocyte sedimentation rate and CRP levels are useful to monitor response to treatment.
Vancomycin remains the first line treatment for many bone and joint infections.
In children 5-10 days of intravenous antibiotics are followed by oral antibiotics.
In adults intravenous antibiotics are indicated for 4-6 weeks.
Intermittent antibiotics may be necessary for suppressing exacerbations.