Septic arthritis is a serious infection of the joints caused by bacteria. This infection causes the joint to be filled with pus cells. These pus cells release substances directed against the bacteria. However, this action can damage the joint structures, bone, and surrounding cartilage.
Septic arthritis develops when bacteria spreads from the source of infection through the bloodstream to a joint. It can result from:
- Infection due to an injection
- Other infections
Septic arthritis can also be caused from injury or trauma. It can result from:
- A penetration wound
- An injury that affects the joint
- Joint surgery/replacement
Septic arthritis can strike at any age. However, it occurs most often in children aged three and younger. In infants, the hip is a frequent site of infection. In toddlers, it is the shoulders, knees, and hips. In children, the most common bacterial causes are:
- Staphylococcus aureus—staph infection
- Streptococcus species, such as group B strep infection
- Streptococcus pneumoniae—a common bacterial cause of pneumonia
Septic arthritis rarely occurs from early childhood through adolescence. After that, it occurs more often. In adults, it most commonly affects weight-bearing joints, such as the knees. In adults, the most common causes are:
- S. aureus
- Neisseria gonorrhoeae—the bacteria that causes gonorrhea
Joint Damage in Knee
Copyright © Nucleus Medical Media, Inc.
Last reviewedAugust 2013by Michael Woods, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.