Q72.42 Longitudinal reduction defect of left femur

ICD-10-CM Q72.42: Longitudinal reduction defect of left femur

ICD-10-CM code Q72.42 identifies a congenital abnormality characterized by a longitudinal reduction defect of the left femur. This diagnostic concept is nested under broader congenital malformations of the musculoskeletal system. Public health sources emphasize differentiating specific limb deficiencies due to distinct causes and associated anomalies. 1 3 6

Plain-language overview

Code Q72.42 designates a congenital abnormality involving a longitudinal reduction defect specifically affecting the left femur, and its terminology record currently holds an active status. 1

What this code represents

The terminology record for Q72.42 lists its official preferred name as Longitudinal reduction defect of left femur and assigns it the semantic type of Congenital Abnormality. 1

Within the ICD-10-CM hierarchy, Q72.42 is a narrower concept under the parent code Q72.4, which represents a longitudinal reduction defect of the femur. 1

Coding details

The broader category Q72.4 falls under Reduction defects of lower limb within the chapter for congenital malformations, deformations, and chromosomal abnormalities. 6

While the parent code Q72.4 includes bilateral and unspecified femur reductions, the specific code Q72.42 provides further specificity by identifying the left side. 1 6

Documentation considerations

Public health surveillance guidelines indicate that distinguishing longitudinal defects from other limb reduction defects is important because these conditions have different causes and associated anomalies. 3 4

The newborn examination is identified as a method to identify longitudinal postaxial limb deficiencies and distinguish them from other limb deficiencies. 3

What the sources add

A prenatal radiographic evaluation source defines longitudinal limb deficiencies as the complete absence or reduction of the long axis of a limb, contrasting with transverse deficiencies. 2

Comparing terminology records, the SNOMEDCT_US concept is mapped to both the broader ICD10CM code Q72.4 and the more specific ICD10CM code Q72.42 for the left femur. 1 5

Sources

1. ICD-10-CM Q72.42 terminology record — National Cancer Institute Enterprise Vocabulary Services; accessed 2026-07-27.
2. Prenatal radiographic evaluation of congenital transverse limb deficiencies: A scoping review — pmc.ncbi.nlm.nih.gov; accessed 2026-07-27.
3. 4.9g Limb Deficiency: Longitudinal Postaxial (Fibula, Ulna, Fifth Ray) — archive.cdc.gov; accessed 2026-07-27.
4. 4.9e Limb Deficiency: Transverse Intercalary (Q71.1, Q72.1, Q72.4) — archive.cdc.gov; accessed 2026-07-27.
5. EVS Explore — evsexplore.semantics.cancer.gov; accessed 2026-07-27.
6. ICD-10-CM Code Q72.4 | Vero — veroscribe.com; accessed 2026-07-27.