Baidc details on undergrad level

1. ACUTE OSTEOMYELITIS
DR.AATIR JAVAID
MBBS, FCPS, CHPE
ASSISTANT PROFESSOR
ORTHOPEDIC SURGERY

2. Definition
• Osteomyelitis is the infection of the bone or BM which leads to a
subsequent Inflammatory process.
• Micro-Organisms may reach bones via the Bloodstream or by
Direct Invasion. (e.g : skin puncture, operation, open fracture)
• Factors which affects it’s development
• Virulence of the organism involved
• Host Factors (Age, Immunity, Diseases)
• Local factors (site of Involvement, damaged muscle presence
of foreign material , vascularity)

3. • It can be classified on the basis of the causative organism, the route,
duration and anatomic location of the infection.
• According to duration: acute, subacute, chronic
• Osteomyelitis usually begins as an acute infection, but it may evolve
into a chronic condition.

4. Types
1. Hematogenous Osteomyelitis
• Bacterial seeding from the blood.
• Seen primarily in Children.
• The most common site
• Metaphysis at the growing end of Long Bones in Children
• Vertebrae in Adults; involving two adjacent vertebrae with
intervertebral disk (may occur pelvis, long bones and clavicle)
2. Direct Inoculation Osteomyelitis
• Its osteomyelitis complicating open fracture or surgical
operation, in which organisms gain entry directly through
the wound.
• Tend to involve multiple organisms. but mainly S.Aureus

5. Acute Haematogenous Osteomyelitis

6. Causative Organisms
• Staph. aureus (Most common)
• Strep. pyogens or pneumoniae (Less).
• H.Influenzae (Young Children)
but still, the most common causative organism for osteomyelitis in young
children is staphylococcus aureus
H.flu infection has become less common due to vaccination
• Salmonella (Sickle-Cell)
still, the most common causative organism for osteomyelitis in sickle cell
anemia patient is staphylococcus aureus
Slamonella is the second most common infection in patients with sickle
cell disease

7. Pathology
1. Inflammation.
• Earliest Change
• Increase interaosseous pressure leads to Pain.
2. Suppuration
• Pus at medulla >> Volkmann canals>>Surface >> Subperiosteal Abscess>>
spread along the shaft>> burst into the soft tissue
• May extend to Epiphysis in Neonates and Children.
• May extend to Interverteberal Discs in Adults.
3. Necrosis/Sequestrum
• Begin in a week.
• causes : increase in intraosseous pressure, vascular stasis, infected
thrombosis, periosteal stripping which increasingly compromise blood
supply

8. 4. New-bone formation
• New bone formation from the stripped surface of periosteum
• Bone thickens to form an involucrum enclosing the infected tissue.
5. Resolution
bone will heal if infection is controlled and intraosseous pressure is
released, though it may remain thickened. or progress to
complications

10. Clinical Features
• Fever , chills and Malaise
• Pain
• Tenderness, Redness, Edema, Warmth (signs of inflammation)
• Restricted Joint Movement

11. INVESTIGATIONS
1. Lab studies
• CBC: leucocytosis
• Elevated CRP & ESR (nonspecific).
• Blood Culture
• Culture & sensitivity test
1. Radiological studies
• X-ray
• MRI
• Radionuclide bone scanning
• CT scan
• US

13. MRI
• Early detection and surgical localization of osteomyelitis.
• sensitivity 90-100%
• help to distinguish between Bone and Soft-Tissue Infection.

14. Radionuclide bone scanning
• A 3-phase bone scan with technetium 99m
• Show increased uptake

15. A. Anterior view B. lateral view
• Both showing the accumulation of radioactive tracer at
the right ankle (arrow). This focal accumulation is
characteristic of osteomyelitis.

16. CT scan
• Spinal vertebral lesions
• Complex anatomy (pelvis, sternum & calcaneus)
Ultrasound
• In children with acute osteomyelitis.
• May demonstrate early changes, 1-2 days after onset of
symptoms.
• Shows soft tissue abscess, fluid collection & periosteal elevation.
• Ultrasonography allows for ultrasound-guided aspiration.
• It does not allow for evaluation of bone cortex.

17. Diagnosis
• Criteria (2 of 4):
1. Localized classic physical findings (tenderness, erythema or
edema).
2. Purulent material on aspiration of affected bone.
3. Positive findings of bone tissue or blood culture.
4. Positive radiological imaging study.

18. Treatment
1. Analgesia
2. Rest of the affected part
3. Antibiotic treatment.
• IV antibiotics for 1-2 weeks then oral for 3-6 weeks.
4. Surgery
• Debridement
• Drainage

19. Complications
1. Septicaemia
2. Extension of infection to the adjacent joint
3. Non union in case of bone fracture
4. Retardation of growth from damage to the epiphysial
cartilage