2024 ICD-10-CM Diagnosis Code S66.3

Injury of extensor muscle, fascia and tendon of other and unspecified finger at wrist and hand level

ICD-10-CM Code:
S66.3
ICD-10 Code for:
Inj extensor musc/fasc/tend and unsp finger at wrs/hnd lv
Is Billable?
Not Valid for Submission
Code Navigator:

Code Classification

  • Injury, poisoning and certain other consequences of external causes
    (S00–T88)
    • Injuries to the wrist, hand and fingers
      (S60-S69)
      • Injury of muscle, fascia and tendon at wrist and hand level
        (S66)

S66.3 is a non-specific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of injury of extensor muscle, fascia and tendon of other and unspecified finger at wrist and hand level. The code is not specific and is NOT valid for the year 2024 for the submission of HIPAA-covered transactions. Category or Header define the heading of a category of codes that may be further subdivided by the use of 4th, 5th, 6th or 7th characters.

Unspecified diagnosis codes like S66.3 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.

Specific Coding Applicable to Inj extensor musc/fasc/tend and unsp finger at wrs/hnd lv

Non-specific codes like S66.3 require more digits to indicate the appropriate level of specificity. Consider using any of the following ICD-10-CM codes with a higher level of specificity when coding for inj extensor musc/fasc/tend and unsp finger at wrs/hnd lv:

  • S66.30 for Unspecified injury of extensor muscle, fascia and tendon of other and unspecified finger at wrist and hand level - NON-BILLABLE CODE

  • S66.300 for Unspecified injury of extensor muscle, fascia and tendon of right index finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.300A for initial encounter - BILLABLE CODE

  • Use S66.300D for subsequent encounter - BILLABLE CODE

  • Use S66.300S for sequela - BILLABLE CODE

  • S66.301 for Unspecified injury of extensor muscle, fascia and tendon of left index finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.301A for initial encounter - BILLABLE CODE

  • Use S66.301D for subsequent encounter - BILLABLE CODE

  • Use S66.301S for sequela - BILLABLE CODE

  • S66.302 for Unspecified injury of extensor muscle, fascia and tendon of right middle finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.302A for initial encounter - BILLABLE CODE

  • Use S66.302D for subsequent encounter - BILLABLE CODE

  • Use S66.302S for sequela - BILLABLE CODE

  • S66.303 for Unspecified injury of extensor muscle, fascia and tendon of left middle finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.303A for initial encounter - BILLABLE CODE

  • Use S66.303D for subsequent encounter - BILLABLE CODE

  • Use S66.303S for sequela - BILLABLE CODE

  • S66.304 for Unspecified injury of extensor muscle, fascia and tendon of right ring finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.304A for initial encounter - BILLABLE CODE

  • Use S66.304D for subsequent encounter - BILLABLE CODE

  • Use S66.304S for sequela - BILLABLE CODE

  • S66.305 for Unspecified injury of extensor muscle, fascia and tendon of left ring finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.305A for initial encounter - BILLABLE CODE

  • Use S66.305D for subsequent encounter - BILLABLE CODE

  • Use S66.305S for sequela - BILLABLE CODE

  • S66.306 for Unspecified injury of extensor muscle, fascia and tendon of right little finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.306A for initial encounter - BILLABLE CODE

  • Use S66.306D for subsequent encounter - BILLABLE CODE

  • Use S66.306S for sequela - BILLABLE CODE

  • S66.307 for Unspecified injury of extensor muscle, fascia and tendon of left little finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.307A for initial encounter - BILLABLE CODE

  • Use S66.307D for subsequent encounter - BILLABLE CODE

  • Use S66.307S for sequela - BILLABLE CODE

  • S66.308 for Unspecified injury of extensor muscle, fascia and tendon of other finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.308A for initial encounter - BILLABLE CODE

  • Use S66.308D for subsequent encounter - BILLABLE CODE

  • Use S66.308S for sequela - BILLABLE CODE

  • S66.309 for Unspecified injury of extensor muscle, fascia and tendon of unspecified finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.309A for initial encounter - BILLABLE CODE

  • Use S66.309D for subsequent encounter - BILLABLE CODE

  • Use S66.309S for sequela - BILLABLE CODE

  • S66.31 for Strain of extensor muscle, fascia and tendon of other and unspecified finger at wrist and hand level - NON-BILLABLE CODE

  • S66.310 for Strain of extensor muscle, fascia and tendon of right index finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.310A for initial encounter - BILLABLE CODE

  • Use S66.310D for subsequent encounter - BILLABLE CODE

  • Use S66.310S for sequela - BILLABLE CODE

  • S66.311 for Strain of extensor muscle, fascia and tendon of left index finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.311A for initial encounter - BILLABLE CODE

  • Use S66.311D for subsequent encounter - BILLABLE CODE

  • Use S66.311S for sequela - BILLABLE CODE

  • S66.312 for Strain of extensor muscle, fascia and tendon of right middle finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.312A for initial encounter - BILLABLE CODE

  • Use S66.312D for subsequent encounter - BILLABLE CODE

  • Use S66.312S for sequela - BILLABLE CODE

  • S66.313 for Strain of extensor muscle, fascia and tendon of left middle finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.313A for initial encounter - BILLABLE CODE

  • Use S66.313D for subsequent encounter - BILLABLE CODE

  • Use S66.313S for sequela - BILLABLE CODE

  • S66.314 for Strain of extensor muscle, fascia and tendon of right ring finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.314A for initial encounter - BILLABLE CODE

  • Use S66.314D for subsequent encounter - BILLABLE CODE

  • Use S66.314S for sequela - BILLABLE CODE

  • S66.315 for Strain of extensor muscle, fascia and tendon of left ring finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.315A for initial encounter - BILLABLE CODE

  • Use S66.315D for subsequent encounter - BILLABLE CODE

  • Use S66.315S for sequela - BILLABLE CODE

  • S66.316 for Strain of extensor muscle, fascia and tendon of right little finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.316A for initial encounter - BILLABLE CODE

  • Use S66.316D for subsequent encounter - BILLABLE CODE

  • Use S66.316S for sequela - BILLABLE CODE

  • S66.317 for Strain of extensor muscle, fascia and tendon of left little finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.317A for initial encounter - BILLABLE CODE

  • Use S66.317D for subsequent encounter - BILLABLE CODE

  • Use S66.317S for sequela - BILLABLE CODE

  • S66.318 for Strain of extensor muscle, fascia and tendon of other finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.318A for initial encounter - BILLABLE CODE

  • Use S66.318D for subsequent encounter - BILLABLE CODE

  • Use S66.318S for sequela - BILLABLE CODE

  • S66.319 for Strain of extensor muscle, fascia and tendon of unspecified finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.319A for initial encounter - BILLABLE CODE

  • Use S66.319D for subsequent encounter - BILLABLE CODE

  • Use S66.319S for sequela - BILLABLE CODE

  • S66.32 for Laceration of extensor muscle, fascia and tendon of other and unspecified finger at wrist and hand level - NON-BILLABLE CODE

  • S66.320 for Laceration of extensor muscle, fascia and tendon of right index finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.320A for initial encounter - BILLABLE CODE

  • Use S66.320D for subsequent encounter - BILLABLE CODE

  • Use S66.320S for sequela - BILLABLE CODE

  • S66.321 for Laceration of extensor muscle, fascia and tendon of left index finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.321A for initial encounter - BILLABLE CODE

  • Use S66.321D for subsequent encounter - BILLABLE CODE

  • Use S66.321S for sequela - BILLABLE CODE

  • S66.322 for Laceration of extensor muscle, fascia and tendon of right middle finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.322A for initial encounter - BILLABLE CODE

  • Use S66.322D for subsequent encounter - BILLABLE CODE

  • Use S66.322S for sequela - BILLABLE CODE

  • S66.323 for Laceration of extensor muscle, fascia and tendon of left middle finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.323A for initial encounter - BILLABLE CODE

  • Use S66.323D for subsequent encounter - BILLABLE CODE

  • Use S66.323S for sequela - BILLABLE CODE

  • S66.324 for Laceration of extensor muscle, fascia and tendon of right ring finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.324A for initial encounter - BILLABLE CODE

  • Use S66.324D for subsequent encounter - BILLABLE CODE

  • Use S66.324S for sequela - BILLABLE CODE

  • S66.325 for Laceration of extensor muscle, fascia and tendon of left ring finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.325A for initial encounter - BILLABLE CODE

  • Use S66.325D for subsequent encounter - BILLABLE CODE

  • Use S66.325S for sequela - BILLABLE CODE

  • S66.326 for Laceration of extensor muscle, fascia and tendon of right little finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.326A for initial encounter - BILLABLE CODE

  • Use S66.326D for subsequent encounter - BILLABLE CODE

  • Use S66.326S for sequela - BILLABLE CODE

  • S66.327 for Laceration of extensor muscle, fascia and tendon of left little finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.327A for initial encounter - BILLABLE CODE

  • Use S66.327D for subsequent encounter - BILLABLE CODE

  • Use S66.327S for sequela - BILLABLE CODE

  • S66.328 for Laceration of extensor muscle, fascia and tendon of other finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.328A for initial encounter - BILLABLE CODE

  • Use S66.328D for subsequent encounter - BILLABLE CODE

  • Use S66.328S for sequela - BILLABLE CODE

  • S66.329 for Laceration of extensor muscle, fascia and tendon of unspecified finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.329A for initial encounter - BILLABLE CODE

  • Use S66.329D for subsequent encounter - BILLABLE CODE

  • Use S66.329S for sequela - BILLABLE CODE

  • S66.39 for Other injury of extensor muscle, fascia and tendon of other and unspecified finger at wrist and hand level - NON-BILLABLE CODE

  • S66.390 for Other injury of extensor muscle, fascia and tendon of right index finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.390A for initial encounter - BILLABLE CODE

  • Use S66.390D for subsequent encounter - BILLABLE CODE

  • Use S66.390S for sequela - BILLABLE CODE

  • S66.391 for Other injury of extensor muscle, fascia and tendon of left index finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.391A for initial encounter - BILLABLE CODE

  • Use S66.391D for subsequent encounter - BILLABLE CODE

  • Use S66.391S for sequela - BILLABLE CODE

  • S66.392 for Other injury of extensor muscle, fascia and tendon of right middle finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.392A for initial encounter - BILLABLE CODE

  • Use S66.392D for subsequent encounter - BILLABLE CODE

  • Use S66.392S for sequela - BILLABLE CODE

  • S66.393 for Other injury of extensor muscle, fascia and tendon of left middle finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.393A for initial encounter - BILLABLE CODE

  • Use S66.393D for subsequent encounter - BILLABLE CODE

  • Use S66.393S for sequela - BILLABLE CODE

  • S66.394 for Other injury of extensor muscle, fascia and tendon of right ring finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.394A for initial encounter - BILLABLE CODE

  • Use S66.394D for subsequent encounter - BILLABLE CODE

  • Use S66.394S for sequela - BILLABLE CODE

  • S66.395 for Other injury of extensor muscle, fascia and tendon of left ring finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.395A for initial encounter - BILLABLE CODE

  • Use S66.395D for subsequent encounter - BILLABLE CODE

  • Use S66.395S for sequela - BILLABLE CODE

  • S66.396 for Other injury of extensor muscle, fascia and tendon of right little finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.396A for initial encounter - BILLABLE CODE

  • Use S66.396D for subsequent encounter - BILLABLE CODE

  • Use S66.396S for sequela - BILLABLE CODE

  • S66.397 for Other injury of extensor muscle, fascia and tendon of left little finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.397A for initial encounter - BILLABLE CODE

  • Use S66.397D for subsequent encounter - BILLABLE CODE

  • Use S66.397S for sequela - BILLABLE CODE

  • S66.398 for Other injury of extensor muscle, fascia and tendon of other finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.398A for initial encounter - BILLABLE CODE

  • Use S66.398D for subsequent encounter - BILLABLE CODE

  • Use S66.398S for sequela - BILLABLE CODE

  • S66.399 for Other injury of extensor muscle, fascia and tendon of unspecified finger at wrist and hand level - NON-BILLABLE CODE

  • Use S66.399A for initial encounter - BILLABLE CODE

  • Use S66.399D for subsequent encounter - BILLABLE CODE

  • Use S66.399S for sequela - BILLABLE CODE

Coding Guidelines

The appropriate 7th character is to be added to each code from block Injury of muscle, fascia and tendon at wrist and hand level (S66). Use the following options for the aplicable episode of care:

  • A - initial encounter
  • D - subsequent encounter
  • S - sequela

Tabular List of Diseases and Injuries

The following annotation back-references are applicable to this diagnosis code. The Tabular List of Diseases and Injuries is a list of ICD-10-CM codes, organized "head to toe" into chapters and sections with coding notes and guidance for inclusions, exclusions, descriptions and more.


Type 2 Excludes

Type 2 Excludes
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
  • Injury of extensor muscle, fascia and tendon of thumb at wrist and hand level S66.2

Patient Education


Hand Injuries and Disorders

No matter how old you are or what you do for a living, you are always using your hands. When there is something wrong with them, you may not be able to do your regular activities.

Hand problems include :

  • Carpal tunnel syndrome - compression of a nerve as it goes through the wrist, often making your fingers feel numb
  • Injuries that result in fractures (broken bones), ruptured ligaments and dislocations
  • Osteoarthritis - wear-and-tear arthritis, which can also cause deformity
  • Tendinitis - irritation of the tendons
  • Disorders and injuries of your fingers and thumb

[Learn More in MedlinePlus]

Wrist Injuries and Disorders

Your wrist connects your hand to your forearm. It is not one big joint; it has several small joints. This makes it flexible and allows you to move your hand in different ways. The wrist has two big forearm bones and eight small bones known as carpals. It also has tendons and ligaments, which are connective tissues. Tendons connect muscles to bones. Ligaments connect bones to each other.

What are the types of wrist injuries and disorders?

Some of the more common types of wrist injuries and disorders are:

  • Carpal tunnel syndrome, which happens when a nerve that runs from your forearm into your palm becomes squeezed at the wrist
  • Ganglion cysts, which are noncancerous lumps or masses
  • Gout, which is a form of arthritis caused by a buildup of uric acid in your joints
  • Fractures (broken bones)
  • Osteoarthritis, the most common type of arthritis. It is caused by wear and tear of the joints.
  • Sprains and strains, which are injuries to ligaments and injuries to muscles or tendons
  • Tendinitis, inflammation of a tendon, usually due to overuse

Who is at risk for wrist injuries and disorders?

Certain things can put you at higher risk of having a wrist problem, including:

  • Doing sports, which can put you at risk for injuries and puts stress on your wrist. For example, you may fall on your outstretched hand when you are skating or snowboarding. Your wrist could be injured while doing contact sports. And other sports such as gymnastics and basketball can strain your wrists.
  • Doing repetitive wrist motions, such as typing on a keyboard, working on an assembly line, or using power tools.
  • Having certain diseases. For example, rheumatoid arthritis can cause wrist pain.

What are the symptoms of wrist injuries and disorders?

The symptoms of a wrist problem can vary, depending on the problem. A common symptom is wrist pain. Some other possible symptoms include swelling, a decrease in wrist strength, and sudden numbness or tingling.

How are wrist injuries and disorders diagnosed?

Your health care provider may use many tools to make a diagnosis:

  • A medical history, which includes asking about your symptoms
  • A physical exam, including checking your wrist strength and range of motion
  • An x-ray or other imaging test
  • Blood tests

What are the treatments for wrist injuries and disorders?

Treatments for wrist pain depends on the type of injury or disorder. They may include:

  • Resting your wrist
  • Wearing a wrist brace or cast
  • Pain relievers
  • Cortisone shots
  • Physical therapy
  • Surgery

Can wrist injuries and disorders be prevented?

To try to prevent wrist problems, you can:

  • Use wrist guards, when doing sports that put you at risk for wrist injuries
  • In the workplace, perform stretching exercises and take frequent rest breaks. You should also pay attention to ergonomics to make sure that you are using the proper wrist position while working.
  • Make sure that you get enough calcium and vitamin D to keep your bones strong

[Learn More in MedlinePlus]

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.