What is the ICD-10 code for flat feet?

The ICD-10 code for acquired flat feet is M21.4-, with specific codes for laterality: M21.41 for the right foot and M21.42 for the left foot. Congenital flat feet are coded under Q66.5-.

How do you code acquired flat feet?

Acquired flat feet are coded using M21.41 for the right foot and M21.42 for the left foot, with documentation of the cause and laterality.

ICD-10 Coding for Flat Feet(M21.41, M21.4, M21.42)

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Learn about ICD-10 coding for flat feet, including acquired and congenital cases, documentation requirements, and common pitfalls.

Also known as:

Pes PlanusFallen Arches

Related ICD-10 Code Ranges

Complete code families applicable to Flat Feet

M00-M99Primary Range

Diseases of the musculoskeletal system and connective tissue

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Code Comparison: When to Use Each Code

Compare key differences between these codes to ensure accurate selection

Code	Description	When to Use	Key Documentation
M21.41	Acquired flat foot, right foot	Use when acquired flat foot is confirmed on the right foot with documented cause.	Weight-bearing X-ray showing arch collapse MRI confirming posterior tibial tendon pathology
M21.42	Acquired flat foot, left foot	Use when acquired flat foot is confirmed on the left foot with documented cause.	Weight-bearing X-ray showing arch collapse MRI confirming posterior tibial tendon pathology
Q66.50	Congenital pes planus, unspecified foot	Use for congenital flat feet without specified laterality.	Pediatric growth charts Absence of trauma history Family history

Primary ICD-10-CM Codes

Flat foot [pes planus] (acquired), right foot

M21.41Billable

Differential Codes

Alternative codes to consider when ruling out similar conditions

Congenital pes planus, unspecified footQ66.50

Use for congenital cases without specified laterality.

Congenital pes planus, bilateralQ66.51

Use for congenital cases with bilateral involvement.

Acquired flat foot, right footM21.41

Use for acquired cases with documented cause.

Documentation & Coding Risks

Avoid these common issues when documenting Flat Feet.

Failing to document laterality for acquired flat feet.

Impact

Clinical: Inaccurate treatment planning., Regulatory: Non-compliance with coding guidelines., Financial: Potential claim denials or reduced reimbursement.

Mitigation

Always include laterality in documentation., Use templates to ensure completeness.

Mixing congenital and acquired codes.

Impact

Reimbursement: May lead to claim denials., Compliance: Violates ICD-10 coding guidelines., Data Quality: Inaccurate clinical data representation.

Mitigation

Use Excludes1 notes to prevent coding both together.

Laterality documentation

Impact

Missing laterality in acquired flat foot cases.

Mitigation

Implement mandatory fields in EHR for laterality.

Frequently Asked Questions

Documentation requirements, coding pitfalls and FAQs for conditions coded with M21.41.

Primary Code

M21.41

Flat foot [pes planus] (acquired), right foot

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ICD-10 codes7

Coding risks3

FAQs2

ICD-10 Coding for Flat Feet(M21.41, M21.4, M21.42)

Documentation & Coding Risks

Frequently Asked Questions

What is the ICD-10 code for flat feet?

How do you code acquired flat feet?

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