DURATION OF POST-SURGICAL ANTIBIOTICS IN CHRONIC OSTEOMYELITIS:

EMPIRIC OR EVIDENCE-BASED?

Fidela Firwan Firdaus

20080310018

INTRODUCTION Chronic osteomyelitis:

An osseus infection that has progressed to bone necrosis and sequestrum formation.

Symptoms Vague/ unclear

History chronic pain, chills, low grade fever

Physical examination local swelling and drainage

Laboratory tests normal leukocyte count, elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels

Imaging modalities for detecting the infection

X-ray, CT scan, MRI

Diagnosis medical history, laboratory findings, different imaging techniques

Eliminate differential diseases

Technetium-99m labeled leukocyte imaging

Guide the antimicrobial drug choice

Bone cultures

TREATMENT OF OSTEOMYELITIS

Divided in 2 basic steps:

• Debridement and obliteration of the subsequent dead space by soft tissue.

• Removal of hardware or fracture stabilization.

DEBRIDEMENT

Includes

• excision of all sequestra along with any infected bone or soft tissue• obliteration of residual dead space

Recurrence rate

• 30% because insufficient debridement

To decrease recurrence, requires:

• segmental resection• application of external fixator• immediate or delayed metaphyseal corticotomy

SOFT TISSUE COVERAGE The best option for reconstructing

chronic osteomyelitic wounds → muscle flaps

The most common muscles used in free-transfer procedures → latissimus dorsi and rectus abdominis

The advantages of a muscle flap:good blood flowantibiotic releaseoxygen tension

ANTIBIOTIC TREATMENT Post-operative antibiotic decided by

culture and sensitivity results. Widely used protocol in adults →

antibiotics intravenous for 4–6 weeks There are no clinical studies or

documented records indicating the superiority of the 4–6-week course of antibiotics over other durations.

ANTIBIOTIC-IMPREGNATED CEMENT BEADS The advantage:

the beads fill dead space produced by debridement

They provide local antibiotic concentrations that are much greater than the minimum inhibitory concentration for most pathogens isolated in orthopedic infections.

MATERIALS AND METHODS Terms: ‘treatment modalities of chronic

osteomyelitis in the lower extremities’, combined with ‘antibacterial agents’/ ’antibiotic’.

Articles published: 1955 - 2008.

RESULTS AND DISCUSSION

Animal studies:• need more studies on

angiogenesis and revascularization

Human studies:• shorter duration of

antimicrobial treatment and well-vascularized flap coverage → possible alternative guideline for treating chronic osteomyelitis in the lower extremities

CONCLUSION

No evidence that prolonged parenteral antibiotics will penetrate the necrotic bone.

• duration of antibiotic treatment• clarify the role of angiogenesis

Studies that we need more in chronic osteomyelitis: