The Kocher criteria is a clinical tool for distinguishing joint diseases, such as septic arthritis. This condition can lead to nonspecific symptoms such as fever, joint pain, and swelling.

There are two types of joint disease: infectious and noninfectious. Infectious joint diseases require immediate medical intervention, while noninfectious cases typically resolve with conservative management.

Therefore, it is crucial to use a clinical tool like Kocher criteria to distinguish between infectious and noninfectious causes of joint diseases.

It is important to note that the Kocher criteria were developed using research on children. Therefore, the criteria are not particularly relevant to adults.

The article discusses more about the Kocher criteria for septic arthritis, its components, and its clinical uses.

A person examining a knee joint.Share on Pinterest
ArLawKa AungTun/Getty Images

The Kocher criteria is a clinical tool for distinguishing cases of joint disease. Clinicians typically use the Kocher criteria for a septic arthritis diagnosis. This arthritis form is an infectious joint disease.

Medical experts named the criteria after Mininder S. Kocher, an orthopedic surgeon and a professor of orthopedic surgery at Harvard Medical School. Dr. Kocher and their team developed the criteria through a retrospective study involving children.

The researchers reviewed clinical cases of children receiving true septic arthritis, presumed septic arthritis diagnosis, and transient hip joint synovitis diagnoses at various hospitals from 1979–1996.

Dr. Kocher and their team discovered that those with true septic arthritis exhibited significantly differing factors from the other group. The findings led to the components of the Kocher criteria.

Septic arthritis is a medical condition characterized by joint inflammation due to infectious organisms, such as bacteria. Other organisms, such as fungi or viruses, may occasionally cause septic arthritis.

Without prompt treatment, septic arthritis can cause joint damage. This means early diagnosis and treatment are necessary to help preserve the structure and function of an affected joint.

Septic arthritis affects the knee joint, but it can affect other joints as well.

Doctors typically combine clinical findings and laboratory results in diagnosing septic arthritis. The following are possible clinical findings in most cases of septic arthritis:

  • joint pain
  • fever
  • swelling
  • difficulty in moving the affected joint
  • limitation in the range of motion and pain on palpation during physical examination

The following investigation findings may suggest septic arthritis:

  • a synovial fluid culture that yields more than 50,000 white cells and 90% neutrophil cell dominance.
  • X-ray of the affected joint showing widened joint spaces with soft tissue bulges and subchondral bony changes.
  • nonspecific findings such as elevated erythrocyte sedimentation rate (ESR), CRP, and white cell count.

The Kocher criteria for diagnosing septic arthritis is divided into the following variables:

  • fever higher than 101.3°F
  • ESR above 40 millimeters per hour (mm/hour)
  • white blood cell (WBC) count greater than 12,000 cells/mm3
  • inability to bear weight on the affected side.

Generally, people with at least one of these four criteria are likely to have septic arthritis.

The following is a scoring metric for using the Kocher criteria:

  • Score 0: None of the four criteria; has less than a 0.2 % risk of septic arthritis.
  • Score 1: Has one of the four criteria. There is a 3% risk of septic arthritis.
  • Score 2: Has two of the four criteria; has a 40% risk of septic arthritis.
  • Score 3: Has three of the four criteria. There is a 93.1% risk of septic arthritis.
  • Score 4: Has all four criteria. There is a 99.6% risk of septic arthritis.

Various online Kocher criteria score calculators help clinicians quickly score a patient using the four diagnostic criteria. The output from these calculators typically gives doctors an idea of the person’s risk of developing septic arthritis.

The Kocher criteria are primarily the ideal tool for assessing or diagnosing hip septic arthritis. They are also primarily relevant to children and not as applicable to adults.

However, septic arthritis can occur in other joints. Further research is essential in validating the use of Kocher criteria in diagnosing septic arthritis in other joints.

The Kocher criteria is an essential clinical tool for identifying those at risk and those with septic arthritis. It helps to differentiate infectious causes of joint diseases, such as septic arthritis, from noninfectious ones, such as transient hip joint synovitis.

Clinicians typically use the Kocher criteria to diagnose septic arthritis, a clinical condition characterized by severe joint inflammation that can damage the joint and result in loss of function.

Therefore, a person with symptoms such as fever, joint pain, swelling, and difficulty moving the affected joint requires prompt medical intervention.