Septic arthritis is a painful infection of a joint cavity, most commonly caused by bacteria. The knee and ankle are common joints in the lower extremity to be infected. The joint cavity is a sterile environment containing synovial fluid. Infection of the joint can occur from either:
- Direct penetration into the joint (ie. an injection)
- Hematogenously from bacteria in the blood
- Other routes such as trauma or surgery
Septic arthritis can cause rapid destruction leading to permanent damage of a joint, thus requires immediate attention. A septic joint typically presents with a fever and a red, hot, swollen joint that is extremely painful to move. Diagnosis is performed via synovial fluid aspiration. The fluid is analyzed for the following tests: clarity, color, presence or absence of crystals, cultures, glucose levels, mucin clot, white blood cell count and viscosity.
Acute joint sepsis requires admission to the hospital for prompt IV antibiotics. An arthrocenteses should be performed every other day to monitor response to therapy and to help remove the infection.
If you think you have a septic joint, go to the emergency department immediately. For more information contact us at Foot& Ankle Doctors, Inc.