ICD-10 Code M00.26 – Other streptococcal arthritis, knee (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code M00.26 – Other streptococcal arthritis, knee
What it is
M00.26 identifies a streptococcal infection of the knee joint causing septic arthritis. Use it when documentation specifies a streptococcal organism, but not a more specific streptococcal category.
Clinical signs
Typical findings include an acutely painful, swollen, warm knee with limited range of motion. Clinical features vary; refer to documentation for organism confirmation and joint involvement.
When to use this code
Use this code when the provider documents septic arthritis of the knee due to streptococcus and does not name another code-specific streptococcal type. It may appear with aspiration, culture, or clinical assessment supporting the diagnosis. Check documentation if the organism or joint is unclear.
Do not use for
Do not use it for nonstreptococcal septic arthritis, traumatic knee pain, or unspecified knee infection. If documentation does not identify streptococcal cause, code the condition as documented.
Coding tip
Confirm both the organism and the knee joint in the record before assigning M00.26.