ICD-10 M23.50
Billable / SpecificChronic instability of knee, unspecified knee
About ICD-10-CM M23.50
ICD-10-CM code M23.50 represents Chronic instability of knee, unspecified knee. This is a billable/specific code in the Musculoskeletal and Connective Tissue chapter (block M23). The 2026 edition of ICD-10-CM M23.50 became effective on October 1, 2025.
Medicare LCD Coverage for M23.50
Local Coverage Determinations (LCDs) from CMS MACs that list M23.50 as a covered diagnosis.
Showing top 10 of 16 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing M23.50.
2 Medicare
1 Aetna
CPT Codes Commonly Billed with M23.50
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
Convert M23.50 to ICD-9-CM
Per CMS General Equivalence Mappings (GEMs), useful for legacy data review and historical claim analysis.
| ICD-10 | ICD-9 | Mapping Flags |
|---|---|---|
| M23.50 | 71785 | 10000 |
| M23.50 | 71886 | 10000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To M23.50
Other codes in section M20-M25 (Other joint disorders).
ICD-10 M23.50, Billing FAQ
Is ICD-10 code M23.50 billable? +
Yes, M23.50 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
What CPT codes are commonly billed with M23.50? +
Procedures frequently paired with M23.50 include: 20610, 73721.
What ICD-9 codes does M23.50 map to? +
Per CMS GEMs, M23.50 maps to ICD-9 codes: 71785, 71886. Useful for legacy data review and historical claim analysis.
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Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on July 16, 2026.
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