ICD-10-CM > M00-M99 > M05-M14 > M12 > M12.4 > M12.46 M12.46 Intermittent hydrarthrosis, knee Non-Billable/Non-Specific Codes M12.461Intermittent hydrarthrosis, right kneeM12.462Intermittent hydrarthrosis, left kneeM12.469Intermittent hydrarthrosis, unspecified knee