2021 ICD-10-CM Code S99.9

Unspecified injury of ankle and foot

Version 2021
Non-Billable Code
Unspecified Code

Not Valid for Submission

S99.9 is a "header" nonspecific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of unspecified injury of ankle and foot. The code is NOT valid for the year 2021 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 S99.9 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.

ICD-10:S99.9
Short Description:Unspecified injury of ankle and foot
Long Description:Unspecified injury of ankle and foot

Code Classification

Specific Coding for Unspecified injury of ankle and foot

Header codes like S99.9 require more digits to indicate the appropriate level of specificity. Consider using any of the following ICD-10 codes with a higher level of specificity when coding for unspecified injury of ankle and foot:

  • S99.91 - Unspecified injury of ankle
  • S99.911 - Unspecified injury of right ankle
  • S99.911A - Unspecified injury of right ankle, initial encounter
  • S99.911D - Unspecified injury of right ankle, subsequent encounter
  • S99.911S - Unspecified injury of right ankle, sequela
  • S99.912 - Unspecified injury of left ankle
  • S99.912A - Unspecified injury of left ankle, initial encounter
  • S99.912D - Unspecified injury of left ankle, subsequent encounter
  • S99.912S - Unspecified injury of left ankle, sequela
  • S99.919 - Unspecified injury of unspecified ankle
  • S99.919A - Unspecified injury of unspecified ankle, initial encounter
  • S99.919D - Unspecified injury of unspecified ankle, subsequent encounter
  • S99.919S - Unspecified injury of unspecified ankle, sequela
  • S99.92 - Unspecified injury of foot
  • S99.921 - Unspecified injury of right foot
  • S99.921A - Unspecified injury of right foot, initial encounter
  • S99.921D - Unspecified injury of right foot, subsequent encounter
  • S99.921S - Unspecified injury of right foot, sequela
  • S99.922 - Unspecified injury of left foot
  • S99.922A - Unspecified injury of left foot, initial encounter
  • S99.922D - Unspecified injury of left foot, subsequent encounter
  • S99.922S - Unspecified injury of left foot, sequela
  • S99.929 - Unspecified injury of unspecified foot
  • S99.929A - Unspecified injury of unspecified foot, initial encounter
  • S99.929D - Unspecified injury of unspecified foot, subsequent encounter
  • S99.929S - Unspecified injury of unspecified foot, sequela

Tabular List of Diseases and Injuries

The Tabular List of Diseases and Injuries is a list of ICD-10 codes, organized "head to toe" into chapters and sections with guidance for inclusions, exclusions, descriptions and more. The following references are applicable to the code S99.9:


7th Character Note

7th Character Note
Certain ICD-10-CM categories have applicable 7th characters. The applicable 7th character is required for all codes within the category, or as the notes in the Tabular List instruct. The 7th character must always be the 7th character in the data field. If a code that requires a 7th character is not 6 characters, a placeholder X must be used to fill in the empty characters.

7th Character

7th Character
Indicates that a seventh character is to be assigned to codes in a subcategory.

Information for Patients


Ankle Injuries and Disorders

Your ankle bone and the ends of your two lower leg bones make up the ankle joint. Your ligaments, which connect bones to one another, stabilize and support it. Your muscles and tendons move it.

The most common ankle problems are sprains and fractures. A sprain is an injury to the ligaments. It may take a few weeks to many months to heal completely. A fracture is a break in a bone. You can also injure other parts of the ankle such as tendons, which join muscles to bone, and cartilage, which cushions your joints. Ankle sprains and fractures are common sports injuries.


[Learn More]

Foot Injuries and Disorders

Each of your feet has 26 bones, 33 joints, and more than 100 tendons, muscles, and ligaments. No wonder a lot of things can go wrong. Here are a few common problems:

Ill-fitting shoes often cause these problems. Aging and being overweight also increase your chances of having foot problems.


[Learn More]

Code History

  • 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 (First year ICD-10-CM implemented into the HIPAA code set)