Acute Pyogenic Osteomyelitis Pathology: Primary focus and stage of inflammation Spread of infection with pus formation Formation of subperiosteal abscess Pus tracks toward skin to form a sinus Bone infarction (Sequestrum) New bone formation (involucrum)
Acute Pyogenic Osteomyelitis Age variation Neonates: Extensive bone necrosis Increased ability to absorb large sequestrum Increased ability to remodel Epiphysio-metaphyseal vascular connection leading to secondary septic arthritis
Acute Pyogenic Osteomyelitis Age variation Adults: No subperiosteal abscess due to adherent periosteum Soft tissue abscess Vascular connection with the joint leading to secondary septic arthritis
Chronic Osteomyelitis Clinical picture Continuous or intermittent suppuration and sinus formation with acute exacerbations. Pain, fever, redness, and tenderness during acute exacerbations. Discharging sinus with +ve/-ve culture. Pathological fracture.
Septic Arthritis Septic arthritis is an infection of the joint usually bacterial, as viral arthritis is usually self limiting and treatment is supportive. 50% of cases in children <3 years The hip joint is the common site in <3years, whereas the knee joint is more common in older children.
Septic Arthritis Acute Septic Arthritis Organism? Route of infection? Pathology: Serous or acute synovitis Serofibrinous Suppurative (purulent) arthritis
Septic Arthritis Acute Septic Arthritis Clinical Pictures General manifestations: constitutional symptoms and signs of acute infection Local manifestation: Swelling, hotness and redness Deformity with muscle spasm Restriction of all movements of the joint The joint is fixed in the position of ease
Septic Arthritis Acute Septic Arthritis Investigations Lab tests/ cultures Plain X-ray Bone scan & Gallium scan Ultrasound Aspiration: if WBC >50,000with >90% PMNLs suspect septic arthritis even if culture is negative.
Septic Arthritis Acute Septic Arthritis Differential Diagnosis Acute osteomyelitis Transient synovitis of the hip (<10) Acute rheumatic fever Haemoarthrosis Haemophilic arthritis