ICD-10-CM > M00-M99 > M20-M25 > M22 > M22.2 > M22.2X M22.2X Patellofemoral disorders Non-Billable/Non-Specific Codes M22.2X1Patellofemoral disorders, right kneeM22.2X2Patellofemoral disorders, left kneeM22.2X9Patellofemoral disorders, unspecified knee