ACUTE OSTEOMYELITIS PPT.pptx

Osteomyelitis is an infection in a bone. Infections can reach a bone by traveling through the bloodstream or spreading from nearby tissue. Infections can also begin in the bone itself if an injury exposes the bone to germs.

Smokers and people with chronic health conditions, such as diabetes or kidney failure, are more at risk of developing osteomyelitis. People who have diabetes may develop osteomyelitis in their feet if they have foot ulcers.

Although once considered incurable, osteomyelitis can now be successfully treated. Most people need surgery to remove areas of the bone that have died. After surgery, strong intravenous antibiotics are typically needed.

1. ACUTE OSTEOMYELITIS DR vasu srivastava Department of Orthopaedics Pacific institute of medical sciences, UDAIPUR

2. Schematic drawing of the consecutive events of acute osteomyelitis. (a) Initial metaphyseal focus . (b) Lateral spread to the cortex . (c) Cortical penetration and periosteal elevation. (d) Formation of thick involucrum . (e ) Further expansion metaphyseal focus with extensive involucrum.

3. WHY STAPH. AUREUS MOST COMMON ??

4. In children younger than 2 years , some blood vessels cross the physis and may allow the spread of infection into the epiphysis. For this reason, infants are susceptible to limb shortening or angular deformity if the physis or epiphysis is damaged from the infection . Otherwise the physis acts as a barrier that prevents the direct spread of a metaphyseal abscess into the epiphysis . The metaphysis has relatively fewer phagocytic cells than the physis or diaphysis, allowing infection to occur more easily in this area. A resulting abscess will break through the thin metaphyseal cortex, forming a subperiosteal abscess. The diaphysis rarely is involved, and extensive sequestration occurs infrequently except in the most severe cases

5. In children older than 2 years of age , the physis effectively acts as a barrier to the spread of a metaphyseal abscess. However, because the metaphyseal cortex in older children is thicker, the diaphysis is at greater risk in these patients. If the infection spreads into the diaphysis, the endosteal blood supply may be jeopardized. With a concurrent subperiosteal abscess, the periosteal blood supply is damaged and can result in extensive sequestration and chronic osteomyelitis if not properly treated.

6. Skeletal changes, such as periosteal reaction or bony destruction, generally are not seen on plain films until 10 to 12 days into the infection. Technetium 99m bone scans can confirm the diagnosis as early as 24 to 48 hours after onset in 90% to 95% of patients. Gallium scans and indium 111-labeled leukocyte scans also can aid in diagnosis when used in conjunction with technetium scanning. The causative organism can be identified in approximately 50% of patients through blood cultures. Bone aspiration usually gives an accurate bacteriological diagnosis and should be performed with a l16-or 18-gauge needle in the area of maximal swelling and tenderness, usually the long bone metaphysis. Magnetic resonance imaging (MRI) can show early inflammatory changes in bone marrow and soft tissue.

7. Epiphyseal childhood osteomyelitis of the right knee. Plain radiograph (a) of the distal femur shows a radiolucent lesion with peripheral sclerotic rim (white arrow) in the epiphysis of the distal femur. After gadolinium contrast administration (coronal T1–Fat–Sat WI, (b) the central part of the lesion is non-enhancing whereas there is subtle peripheral rim enhancement (white arrow) with moderate enhancement of the surrounding bone marrow edema

8. In 1983 Nade proposed five principles for the treatment of acute hematogenous osteomyelitis that are still applicable today: an appropriate antibiotic will be effective before pus formation; (2) or antibiotics will not sterilize avascular tissues abscesses and such areas require surgical removal; 3) if such removal is effective , antibiotics should prevent their reformation and therefore primary wound closure should be safe ; (4) surgery should not further damage already ischemic bone and soft tissue; (5) antibiotics should be continued after surgery. TREATMENT

9. The CRP should be checked every 2 to 3 days after the initiation of antibiotic therapy . If no appreciable clinical response to antibiotic treatment is noted within 24 to 48 hours, then occult abscesses must be sought and surgical drainage considered. The two main indications for Surgery in acute hematogenous osteomyelitis are (1) the presence of an abscess requiring drainage and (2) failure of the patient to improve despite appropriate intravenous antibiotic treatment.

10. The duration of antibiotic therapy is controversial ; however, the current trend is toward a shorter course of intravenous antibiotics, followed by oral antibiotics, and monitoring of serum antibiotic levels .