ICD-10 Code M21.42 - Flat foot [pes planus] (acquired), left foot

ICD-10-CM Diagnosis Code M21.42

Diagnosis Code: M21.42 (Raw: M2142)

Description: Flat foot [pes planus] (acquired), left foot

Classification: International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM)

Fiscal Year: 2026

CMS Section 111 Status: Valid for reporting.

Overview & Clinical Details

ICD-10-CM code M21.42 is designated for Flat foot [pes planus] (acquired), left foot. In medical documentation and insurance billing, this code is utilized to specify medical diagnosis for patient records, reimbursement workflows, and compliance under CMS Section 111 mandatory insurer reporting guidelines.