S66.11 – Strain of flexor muscle, fascia and tendon of other and unspecified finger at wrist and hand level

ICD-10-CM 2027 diagnosis code · Injuries to the wrist, hand and fingers

Non-billable header

ICD-10-CM code S66.11

Code: S66.11 (claims format: S6611)
Description: Strain of flexor muscle, fascia and tendon of other and unspecified finger at wrist and hand level
Short description: Strain flexor musc/fasc/tend and unsp finger at wrs/hnd lv
Billable: No – use a more specific code below
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 19. Injury, poisoning and certain other consequences of external causes (S00-T88)
Block: S60-S69 Injuries to the wrist, hand and fingers
Parent codes: S66 › S66.1

Billable codes under S66.11

S66.11 is a header code and cannot be used on claims. Choose the most specific code:

S66.110 – Strain of flexor muscle, fascia and tendon of right index finger at wrist and hand levelHeader (more codes below)
S66.111 – Strain of flexor muscle, fascia and tendon of left index finger at wrist and hand levelHeader (more codes below)
S66.112 – Strain of flexor muscle, fascia and tendon of right middle finger at wrist and hand levelHeader (more codes below)
S66.113 – Strain of flexor muscle, fascia and tendon of left middle finger at wrist and hand levelHeader (more codes below)
S66.114 – Strain of flexor muscle, fascia and tendon of right ring finger at wrist and hand levelHeader (more codes below)
S66.115 – Strain of flexor muscle, fascia and tendon of left ring finger at wrist and hand levelHeader (more codes below)
S66.116 – Strain of flexor muscle, fascia and tendon of right little finger at wrist and hand levelHeader (more codes below)
S66.117 – Strain of flexor muscle, fascia and tendon of left little finger at wrist and hand levelHeader (more codes below)
S66.118 – Strain of flexor muscle, fascia and tendon of other finger at wrist and hand levelHeader (more codes below)
S66.119 – Strain of flexor muscle, fascia and tendon of unspecified finger at wrist and hand levelHeader (more codes below)

7th character values

Codes in this category need a 7th character to describe the encounter or episode of care (use placeholder X for empty positions).

Character	Meaning
`A`	initial encounter
`D`	subsequent encounter
`S`	sequela

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

S66 – Injury of muscle, fascia and tendon at wrist and hand level

Excludes2 (not included here):

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

Code also:

any associated open wound (S61.-)

7th character note:

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

S66.1 – Injury of flexor muscle, fascia and tendon of other and unspecified finger at wrist and hand level

Excludes2 (not included here):

Injury of long flexor muscle, fascia and tendon of thumb at wrist and hand level (S66.0-)

Block S60-S69

Excludes2 (not included here):

burns and corrosions (T20-T32)
frostbite (T33-T34)
insect bite or sting, venomous (T63.4)

Index terms for S66.11

Entries in the ICD-10-CM alphabetic index that lead to this code:

Related codes in S66.1

Frequently asked questions

What is ICD-10 code S66.11?

S66.11 is the ICD-10-CM code for strain of flexor muscle, fascia and tendon of other and unspecified finger at wrist and hand level, in the block S60-S69 (Injuries to the wrist, hand and fingers).

Is S66.11 a billable code?

No. S66.11 is a header code with more specific child codes; report one of the billable codes listed above.

What category does S66.11 belong to?

It belongs to category S66 – Injury of muscle, fascia and tendon at wrist and hand level.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.