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S66.399S

S66.399S: Other injury of extensor muscle, fascia and tendon of unspecified finger at wrist and hand level, sequela

Billable / specific codeICD-10-CMPOA exemptunspecified

S66.399S is a billable, specific ICD-10-CM code for other injury of extensor muscle, fascia and tendon of unspecified finger at wrist and hand level, sequela. It is valid for submission on a claim.

Check S66.399S with the rest of the claim: free scrubber

7th character "S": sequela

The appropriate 7th character is to be added to each code from category S66

A
initial encounter
D
subsequent encounter
S
sequela

Excludes2 inherited from the categories above S66.399S

Not part of this code, but both may be coded when both are present.

Written on S66.3: Injury of extensor muscle, fascia and tendon of other and unspecified finger at wrist and hand level

  • Injury of extensor muscle, fascia and tendon of thumb at wrist and hand level (S66.2-)

Written on S66: Injury of muscle, fascia and tendon at wrist and hand level

  • sprain of joints and ligaments of wrist and hand (S63.-)

Risk adjustment

No CMS-HCC V28 category: this code does not change a RAF score.

Code history

Unchanged in every release from FY2024 to FY2027.

Other codes under S66.399

ICD-10-CMFY2027· effective October 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release: see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.