ICD-10-CM > M00-M99 > M05-M14 > M1A > M1A.0 > M1A.06 > M1A.069 M1A.069 Idiopathic chronic gout, unspecified knee Non-Billable/Non-Specific Codes M1A.0690..., without tophus (tophi)M1A.0691..., with tophus (tophi)