S66.129A is the authoritative medical code for Laceration of flexor muscle, fascia and tendon of unspecified finger at wrist and hand level, initial encounter. This classification is used in medical billing and clinical recording to specify the clinical criteria for laceration of flexor muscle, fascia and tendon of unspecified finger at wrist and hand level, initial encounter (ICD-10-CM S66.129A), ensuring healthcare documentation aligns with 2026 federal coding standards.
Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.
Official Registry Overview & Definition
Laceration of flexor muscle, fascia and tendon of unspecified finger at wrist and hand level, initial encounter is a billable ICD-10-CM diagnosis code S66.129A. Excludes2 (not included here): Injury of long flexor muscle, fascia and tendon of thumb at wrist and hand level S66.0-; sprain of joints and ligaments of wrist and hand S63.-; burns and corrosions T20-T32; frostbite T33-T34; insect bite or sting, venomous T63.4. Code also: any associated open wound S61.-. 7th character: The appropriate 7th character is to be added to each code from category S66.
Official Tabular Instructional Notes
Sequencing, inclusion, and exclusion notes published for S66.129A in the official ICD-10-CM tabular list.
Excludes2 — Not Included Here
Conditions not covered by this code, but which may be reported alongside it when both are present.
- Injury of long flexor muscle, fascia and tendon of thumb at wrist and hand level S66.0-
- sprain of joints and ligaments of wrist and hand S63.-
- burns and corrosions T20-T32
- frostbite T33-T34
- insect bite or sting, venomous T63.4
Code Also
Additional codes that may be required to fully describe the encounter.
- any associated open wound S61.-
Frequently Asked Questions (FAQ) & Clinical Guidance
Does S66.129A require a 7th character?
Yes. The appropriate 7th character is to be added to each code from category S66.
Can S66.129A be reported alongside related conditions?
Per Excludes2 instructions, S66.129A and the following may both be reported when both are present: Injury of long flexor muscle, fascia and tendon of thumb at wrist and hand level (S66.0-); sprain of joints and ligaments of wrist and hand (S63.-); burns and corrosions (T20-T32); frostbite (T33-T34).
Codes in This Family (40)
Official ICD-10-CM classifications in the same code family as S66.129A, with their registry titles.
- S66 — Injury of muscle, fascia and tendon at wrist and hand level
- S66.0 — Injury of long flexor muscle, fascia and tendon of thumb at wrist and hand level
- S66.00 — Unspecified injury of long flexor muscle, fascia and tendon of thumb at wrist and hand level
- S66.001 — Unspecified injury of long flexor muscle, fascia and tendon of right thumb at wrist and hand level
- S66.001A — Unspecified injury of long flexor muscle, fascia and tendon of right thumb at wrist and hand level, initial encounter
- S66.001D — Unspecified injury of long flexor muscle, fascia and tendon of right thumb at wrist and hand level, subsequent encounter
- S66.001S — Unspecified injury of long flexor muscle, fascia and tendon of right thumb at wrist and hand level, sequela
- S66.002 — Unspecified injury of long flexor muscle, fascia and tendon of left thumb at wrist and hand level
- S66.002A — Unspecified injury of long flexor muscle, fascia and tendon of left thumb at wrist and hand level, initial encounter
- S66.002D — Unspecified injury of long flexor muscle, fascia and tendon of left thumb at wrist and hand level, subsequent encounter
- S66.002S — Unspecified injury of long flexor muscle, fascia and tendon of left thumb at wrist and hand level, sequela
- S66.009 — Unspecified injury of long flexor muscle, fascia and tendon of unspecified thumb at wrist and hand level
- S66.009A — Unspecified injury of long flexor muscle, fascia and tendon of unspecified thumb at wrist and hand level, initial encounter
- S66.009D — Unspecified injury of long flexor muscle, fascia and tendon of unspecified thumb at wrist and hand level, subsequent encounter
- S66.009S — Unspecified injury of long flexor muscle, fascia and tendon of unspecified thumb at wrist and hand level, sequela
- S66.01 — Strain of long flexor muscle, fascia and tendon of thumb at wrist and hand level
- S66.011 — Strain of long flexor muscle, fascia and tendon of right thumb at wrist and hand level
- S66.011A — Strain of long flexor muscle, fascia and tendon of right thumb at wrist and hand level, initial encounter
- S66.011D — Strain of long flexor muscle, fascia and tendon of right thumb at wrist and hand level, subsequent encounter
- S66.011S — Strain of long flexor muscle, fascia and tendon of right thumb at wrist and hand level, sequela
- S66.012 — Strain of long flexor muscle, fascia and tendon of left thumb at wrist and hand level
- S66.012A — Strain of long flexor muscle, fascia and tendon of left thumb at wrist and hand level, initial encounter
- S66.012D — Strain of long flexor muscle, fascia and tendon of left thumb at wrist and hand level, subsequent encounter
- S66.012S — Strain of long flexor muscle, fascia and tendon of left thumb at wrist and hand level, sequela
- S66.019 — Strain of long flexor muscle, fascia and tendon of unspecified thumb at wrist and hand level
- S66.019A — Strain of long flexor muscle, fascia and tendon of unspecified thumb at wrist and hand level, initial encounter
- S66.019D — Strain of long flexor muscle, fascia and tendon of unspecified thumb at wrist and hand level, subsequent encounter
- S66.019S — Strain of long flexor muscle, fascia and tendon of unspecified thumb at wrist and hand level, sequela
- S66.02 — Laceration of long flexor muscle, fascia and tendon of thumb at wrist and hand level
- S66.021 — Laceration of long flexor muscle, fascia and tendon of right thumb at wrist and hand level
- S66.021A — Laceration of long flexor muscle, fascia and tendon of right thumb at wrist and hand level, initial encounter
- S66.021D — Laceration of long flexor muscle, fascia and tendon of right thumb at wrist and hand level, subsequent encounter
- S66.021S — Laceration of long flexor muscle, fascia and tendon of right thumb at wrist and hand level, sequela
- S66.022 — Laceration of long flexor muscle, fascia and tendon of left thumb at wrist and hand level
- S66.022A — Laceration of long flexor muscle, fascia and tendon of left thumb at wrist and hand level, initial encounter
- S66.022D — Laceration of long flexor muscle, fascia and tendon of left thumb at wrist and hand level, subsequent encounter
- S66.022S — Laceration of long flexor muscle, fascia and tendon of left thumb at wrist and hand level, sequela
- S66.029 — Laceration of long flexor muscle, fascia and tendon of unspecified thumb at wrist and hand level
- S66.029A — Laceration of long flexor muscle, fascia and tendon of unspecified thumb at wrist and hand level, initial encounter
- S66.029D — Laceration of long flexor muscle, fascia and tendon of unspecified thumb at wrist and hand level, subsequent encounter
Indexed Clinical Terms (1)
Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code.
- Injury, muscle (and fascia) (and tendon), finger, flexor (forearm level), hand level, laceration
Related Codes & Numerical Sequence (Crawl Map)
Search engines and indexers are advised to traverse adjacent medical codes in this sub-chapter range to find correlated diagnoses or therapeutic procedures:
ICD Code S61.129A
Laceration with foreign body of unspecified thumb with damage to nail, initial encounter
ICD Code S68.129A
Partial traumatic metacarpophalangeal amputation of unspecified finger, initial encounter