5.3. Bone and Soft Tissue Infection - Acute Septic Arthritis Flashcards
What is the Route of Infection for Acute Septic Arthritis?
- Direct Invasion
- Eruption of a Bone Abscess
- Haematogenous (Blood) Spread
What are the different ways Acute Septic Arthritis can be spread, via Direct Invasion?
- A Penetrating Wound (Iatrogenic - Joint Injection)
- An Intra-Articular Injury
- Arthroscopy
What are the most common causative Organisms of Acute Septic Arthritis?
- Staph. Aureus
- H. Influenzae
- Strep. Pyogenes
- E. Coli
What is the Pathology of Acute Septic Arthritis?
Due to the infection:
- Articular Cartilage is attacked by the Bacterial Toxins and Cellular Enzymes
- This causes Acute Synovitis with Purulent Joint Efusion
- This leads to complete distruction of the Articular Cartilage
What are the recovery options (Sequelae) for Acute Septic Arthritis?
- Complete Recovery
- Partial Loss of the Articular Cartilage, and Subsequent Osteoarthritis
- Fibrous / Bony Ankylosis
What is the Clinical Presentation of Acute Septic Arthritis in a Neonate?
- Irritability
- Resistant to Movement
- Ill
What is the Clinical Presentation of Acute Septic Arthritis in a Child?
- Reluctance to move the Joint
- Increase in Temperature
- Increase in Pulse
- Increase in tenderness
Which joints does Acute Septic Arthritis most commonly present in Adults?
Superficial Joints:
- Knee
- Ankle
- Wrist
How common is Acute Septic Arthritis in healthy adults?
Rare
What are the investigations of Acute Septic Arthritis?
- Full Blood Count
- White Cell Count
- Inflammatory Markers - ESR + CRP
- Blood Cultures
- X-Ray
- Ultrasound
- Fine Needle Aspiration
What is the most common cause of Acute Septic Arthritis in an Adult?
An Infected Joint Replacement
What is the outcome of an Infected Joint Replacement?
- Removal or Arthroplasty
- Amputation
- Death
Note this is very rare but disasterous
What is the Differential Diagnosis of Acute Septic Arthritis?
- Acute Osteomyelitis
- Trauma
- Irritable Joint Syndrome
- Haemophilia
- Rheumatic Fever
- Gout
- Gaucher’s Disease
What is the treatment of Acute Septic Arthritis?
- General Supportive Measures (Fluids + O2)
- Antibiotics
- Surgical Drainage and Lavage - emergency