ICD-10-CM · FY 2026 APRIL UPDATE

S66.3

Injury of extensor muscle, fascia and tendon of other and unspecified finger 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

CODE	DESCRIPTION	TYPE
S66.30	Unspecified injury of extensor muscle, fascia and tendon of other and unspecified finger at wrist and hand level	Category
S66.300	Unspecified injury of extensor muscle, fascia and tendon of right index finger at wrist and hand level	Category
S66.300A	Unspecified injury of extensor muscle, fascia and tendon of right index finger at wrist and hand level, initial encounter	Billable
S66.300D	Unspecified injury of extensor muscle, fascia and tendon of right index finger at wrist and hand level, subsequent encounter	Billable
S66.300S	Unspecified injury of extensor muscle, fascia and tendon of right index finger at wrist and hand level, sequela	Billable
S66.301	Unspecified injury of extensor muscle, fascia and tendon of left index finger at wrist and hand level	Category
S66.301A	Unspecified injury of extensor muscle, fascia and tendon of left index finger at wrist and hand level, initial encounter	Billable
S66.301D	Unspecified injury of extensor muscle, fascia and tendon of left index finger at wrist and hand level, subsequent encounter	Billable
S66.301S	Unspecified injury of extensor muscle, fascia and tendon of left index finger at wrist and hand level, sequela	Billable
S66.302	Unspecified injury of extensor muscle, fascia and tendon of right middle finger at wrist and hand level	Category
S66.302A	Unspecified injury of extensor muscle, fascia and tendon of right middle finger at wrist and hand level, initial encounter	Billable
S66.302D	Unspecified injury of extensor muscle, fascia and tendon of right middle finger at wrist and hand level, subsequent encounter	Billable
S66.302S	Unspecified injury of extensor muscle, fascia and tendon of right middle finger at wrist and hand level, sequela	Billable
S66.303	Unspecified injury of extensor muscle, fascia and tendon of left middle finger at wrist and hand level	Category
S66.303A	Unspecified injury of extensor muscle, fascia and tendon of left middle finger at wrist and hand level, initial encounter	Billable
S66.303D	Unspecified injury of extensor muscle, fascia and tendon of left middle finger at wrist and hand level, subsequent encounter	Billable
S66.303S	Unspecified injury of extensor muscle, fascia and tendon of left middle finger at wrist and hand level, sequela	Billable
S66.304	Unspecified injury of extensor muscle, fascia and tendon of right ring finger at wrist and hand level	Category
S66.304A	Unspecified injury of extensor muscle, fascia and tendon of right ring finger at wrist and hand level, initial encounter	Billable
S66.304D	Unspecified injury of extensor muscle, fascia and tendon of right ring finger at wrist and hand level, subsequent encounter	Billable
S66.304S	Unspecified injury of extensor muscle, fascia and tendon of right ring finger at wrist and hand level, sequela	Billable
S66.305	Unspecified injury of extensor muscle, fascia and tendon of left ring finger at wrist and hand level	Category
S66.305A	Unspecified injury of extensor muscle, fascia and tendon of left ring finger at wrist and hand level, initial encounter	Billable
S66.305D	Unspecified injury of extensor muscle, fascia and tendon of left ring finger at wrist and hand level, subsequent encounter	Billable
S66.305S	Unspecified injury of extensor muscle, fascia and tendon of left ring finger at wrist and hand level, sequela	Billable
S66.306	Unspecified injury of extensor muscle, fascia and tendon of right little finger at wrist and hand level	Category
S66.306A	Unspecified injury of extensor muscle, fascia and tendon of right little finger at wrist and hand level, initial encounter	Billable
S66.306D	Unspecified injury of extensor muscle, fascia and tendon of right little finger at wrist and hand level, subsequent encounter	Billable
S66.306S	Unspecified injury of extensor muscle, fascia and tendon of right little finger at wrist and hand level, sequela	Billable
S66.307	Unspecified injury of extensor muscle, fascia and tendon of left little finger at wrist and hand level	Category

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.