ICD-10-CM 2027 diagnosis code
Q66.21Congenital metatarsus primus varus
Q66.21 is a header code, so it can't be reported by itself. Choose one of the 3 more specific codes beneath it.
Looking up by condition? See ICD-10 code for Primus varus.
Code last changed in FY2020 (effective October 1, 2019). Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About Q66.21
Q66.21 is the ICD-10-CM diagnosis code for congenital metatarsus primus varus. It belongs to category Q66 (congenital deformities of feet), block Q65-Q79 (congenital malformations and deformations of the musculoskeletal system) and chapter 17 (congenital malformations, deformations, chromosomal abnormalities, and genetic disorders). It is a header code, so it can't be reported by itself; one of its 3 subcodes must be used instead.
Within Q66.2 (congenital metatarsus (primus) varus), Q66.21 is specifically for congenital metatarsus primus varus. Related codes cover adductus (Q66.22).
To report this condition, pick the subcode that matches the documentation: Q66.211 (right foot), Q66.212 (left foot) and Q66.219 (unspecified foot).
It was added in FY2017, effective October 1, 2016, and changed in FY2020.
Before ICD-10, this condition was coded in ICD-9-CM as 754.52 (metatarsus primus varus).
Specific codes under Q66.21
Notes that apply from higher levels
Instructions written at a parent level also apply to Q66.21.
Broader instructions also apply from Chapter 17: Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders.
Alphabetic index entries
2 entriesTerms in the official ICD-10-CM index that lead to Q66.21.
ICD-9-CM equivalent
Converter →- 754.52Metatarsus primus varusexact
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2017 (effective 10/1/2016): Added
- FY2020 (effective 10/1/2019): Expanded — no longer billable