ICD-10-CM > M00-M99 > M20-M25 > M22 > M22.9 M22.9 Unspecified disorder of patella Non-Billable/Non-Specific Codes M22.90Unspecified disorder of patella, unspecified kneeM22.91Unspecified disorder of patella, right kneeM22.92Unspecified disorder of patella, left knee