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ICD-10-CM · FY 2026 APRIL UPDATE

S66.00

Unspecified injury of long flexor muscle, fascia and tendon of thumb at wrist and hand level

Diagnosis reference

Nonbillable category

This entry is a category or subcategory. Choose the appropriate billable descendant based on the clinical documentation.

Effective periodOctober 1, 2026–September 30, 2027
SourceCMS ICD-10-CM order file
ClassificationDiagnosis · clinical modification

Related entries

Up to 30 descendants in this category

CODEDESCRIPTIONTYPE
S66.001Unspecified injury of long flexor muscle, fascia and tendon of right thumb at wrist and hand levelCategory
S66.001AUnspecified injury of long flexor muscle, fascia and tendon of right thumb at wrist and hand level, initial encounterBillable
S66.001DUnspecified injury of long flexor muscle, fascia and tendon of right thumb at wrist and hand level, subsequent encounterBillable
S66.001SUnspecified injury of long flexor muscle, fascia and tendon of right thumb at wrist and hand level, sequelaBillable
S66.002Unspecified injury of long flexor muscle, fascia and tendon of left thumb at wrist and hand levelCategory
S66.002AUnspecified injury of long flexor muscle, fascia and tendon of left thumb at wrist and hand level, initial encounterBillable
S66.002DUnspecified injury of long flexor muscle, fascia and tendon of left thumb at wrist and hand level, subsequent encounterBillable
S66.002SUnspecified injury of long flexor muscle, fascia and tendon of left thumb at wrist and hand level, sequelaBillable
S66.009Unspecified injury of long flexor muscle, fascia and tendon of unspecified thumb at wrist and hand levelCategory
S66.009AUnspecified injury of long flexor muscle, fascia and tendon of unspecified thumb at wrist and hand level, initial encounterBillable
S66.009DUnspecified injury of long flexor muscle, fascia and tendon of unspecified thumb at wrist and hand level, subsequent encounterBillable
S66.009SUnspecified injury of long flexor muscle, fascia and tendon of unspecified thumb at wrist and hand level, sequelaBillable

Use the complete reference

This reference does not reproduce the full tabular hierarchy, inclusion notes, Excludes1/2 notes, sequencing instructions, or seventh-character rules. Review the official tables and coding guidelines.

Open official CMS files

ICD-10-CM codes describe diagnoses. They do not have an independent Medicare PFS reimbursement amount, and billability alone does not establish coverage.