Septic Arthritis



Bacteria is the most common cause of this infection. Viruses and fungi can also cause it.

The infection may be started by an organism that:

  • Has entered the blood from an infection somewhere else in the body
  • Entered the blood from IV drug use
  • Is outside the body and entered through a wound or incision from surgery
Joint Damage in Knee
Knee arthitis
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Risk Factors

Septic arthritis is more common in older adults. Things that may raise the risk in adults are:

  • Taking medicines or having health problems that weaken the immune system, such as HIV
  • A history of joint problems or having other types of arthritis
  • Joint replacement or organ transplant surgery
  • Long-term health problems, such as diabetes
  • Recent joint injections
  • A history of IV drug use

This problem is also more common in children who are male and those who are under 3 years of age. Things that may raise the risk in children are:

  • Trauma
  • A weakened immune system
  • Respiratory distress syndrome
  • Having an umbilical artery catheter
  • A history of a urinary tract infections



The knee, hip, shoulder, ankle, elbow, and wrist are the most common sites of septic arthritis in adults. Problems may be:

  • A warm, red, painful joint
  • Joint swelling
  • Problems moving the joint or limb
  • Fever

The knee and hip are the most common sites for in children. Problems may be:

  • Crying when a joint is moved, such as during a diaper change
  • Warmth and redness
  • Swelling
  • Problems moving a joint or limb
  • Problems walking
  • Fever


The doctor will ask about symptoms and health history. A physical exam will be done.

Tests may be done to look for signs of infection. This can be done with:

  • Joint fluid tests
  • Blood tests

Pictures of the area may be taken. This can be done with:

  • X-rays
  • MRI scan



The goal is to treat the infection. This is done with antibiotics.

Fluid may be removed to ease pressure in the joint. This may be done with a needle or through surgery.


There are no known guidelines to prevent septic arthritis.

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Edits to original content made by Denver Health.