2021 ICD-10-CM Code S86.91

Strain of unspecified muscle and tendon at lower leg level

  1. ICD-10-CM Index
  2. Chapter: S00–T98
  3. Section: S80-S89
  4. Block: S86
  5. S86.91 - Strain of unspecified muscle and tendon at lower leg level
Version 2021
Non-Billable Code
Unspecified Code

Not Valid for Submission

S86.91 is a "header" nonspecific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of strain of unspecified muscle and tendon at lower leg level. 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 S86.91 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:S86.91
Short Description:Strain of unspecified muscle and tendon at lower leg level
Long Description:Strain of unspecified muscle and tendon at lower leg level

Code Classification

Specific Coding for Strain of unspecified muscle and tendon at lower leg level

Header codes like S86.91 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 strain of unspecified muscle and tendon at lower leg level:

  • S86.911 - Strain of unspecified muscle(s) and tendon(s) at lower leg level, right leg
  • S86.911A - Strain of unspecified muscle(s) and tendon(s) at lower leg level, right leg, initial encounter
  • S86.911D - Strain of unspecified muscle(s) and tendon(s) at lower leg level, right leg, subsequent encounter
  • S86.911S - Strain of unspecified muscle(s) and tendon(s) at lower leg level, right leg, sequela
  • S86.912 - Strain of unspecified muscle(s) and tendon(s) at lower leg level, left leg
  • S86.912A - Strain of unspecified muscle(s) and tendon(s) at lower leg level, left leg, initial encounter
  • S86.912D - Strain of unspecified muscle(s) and tendon(s) at lower leg level, left leg, subsequent encounter
  • S86.912S - Strain of unspecified muscle(s) and tendon(s) at lower leg level, left leg, sequela
  • S86.919 - Strain of unspecified muscle(s) and tendon(s) at lower leg level, unspecified leg
  • S86.919A - Strain of unspecified muscle(s) and tendon(s) at lower leg level, unspecified leg, initial encounter
  • S86.919D - Strain of unspecified muscle(s) and tendon(s) at lower leg level, unspecified leg, subsequent encounter
  • S86.919S - Strain of unspecified muscle(s) and tendon(s) at lower leg level, unspecified leg, sequela

Index to Diseases and Injuries

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code S86.91 are found in the index:

Information for Patients


Leg Injuries and Disorders

Your legs are made up of bones, blood vessels, muscles, and other connective tissue. They are important for motion and standing. Playing sports, running, falling, or having an accident can damage your legs. Common leg injuries include sprains and strains, joint dislocations, and fractures.

These injuries can affect the entire leg, or just the foot, ankle, knee, or hip. Certain diseases also lead to leg problems. For example, knee osteoarthritis, common in older people, can cause pain and limited motion. Problems in your veins in your legs can lead to varicose veins or deep vein thrombosis.


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Sprains and Strains

A sprain is a stretched or torn ligament. Ligaments are tissues that connect bones at a joint. Falling, twisting, or getting hit can all cause a sprain. Ankle and wrist sprains are common. Symptoms include pain, swelling, bruising, and being unable to move your joint. You might feel a pop or tear when the injury happens.

A strain is a stretched or torn muscle or tendon. Tendons are tissues that connect muscle to bone. Twisting or pulling these tissues can cause a strain. Strains can happen suddenly or develop over time. Back and hamstring muscle strains are common. Many people get strains playing sports. Symptoms include pain, muscle spasms, swelling, and trouble moving the muscle.

At first, treatment of both sprains and strains usually involves resting the injured area, icing it, wearing a bandage or device that compresses the area, and medicines. Later treatment might include exercise and physical therapy.

NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases


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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)

Previous Code: S86.909S

Related Codes

Next Code: S86.911