2021 ICD-10-CM Code M23.229

Derangement of posterior horn of medial meniscus due to old tear or injury, unspecified knee

Version 2021
Billable Code
Unspecified Code
MS-DRG Mapping

Valid for Submission

M23.229 is a billable diagnosis code used to specify a medical diagnosis of derangement of posterior horn of medial meniscus due to old tear or injury, unspecified knee. The code M23.229 is valid during the fiscal year 2021 from October 01, 2020 through September 30, 2021 for the submission of HIPAA-covered transactions.

The ICD-10-CM code M23.229 might also be used to specify conditions or terms like derangement of medial meniscus due to injury of knee, derangement of meniscus due to injury of knee, derangement of posterior horn of medial meniscus, derangement of posterior horn of medial meniscus, derangement of posterior horn of medial meniscus due to injury of knee , old tear of posterior horn of medial meniscus, etc.

Unspecified diagnosis codes like M23.229 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:M23.229
Short Description:Derang of post horn of med mensc d/t old tear/inj, unsp knee
Long Description:Derangement of posterior horn of medial meniscus due to old tear or injury, unspecified knee

Code Classification

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

Convert M23.229 to ICD-9 Code

The General Equivalency Mapping (GEM) crosswalk indicates an approximate mapping between the ICD-10 code M23.229 its ICD-9 equivalent. The approximate mapping means there is not an exact match between the ICD-10 code and the ICD-9 code and the mapped code is not a precise representation of the original code.

Information for Patients


Knee Injuries and Disorders

Your knee joint is made up of bone, cartilage, ligaments and fluid. Muscles and tendons help the knee joint move. When any of these structures is hurt or diseased, you have knee problems. Knee problems can cause pain and difficulty walking.

Knee problems are very common, and they occur in people of all ages. Knee problems can interfere with many things, from participation in sports to simply getting up from a chair and walking. This can have a big impact on your life.

The most common disease affecting the knee is osteoarthritis. The cartilage in the knee gradually wears away, causing pain and swelling.

Injuries to ligaments and tendons also cause knee problems. A common injury is to the anterior cruciate ligament (ACL). You usually injure your ACL by a sudden twisting motion. ACL and other knee injuries are common sports injuries.

Treatment of knee problems depends on the cause. In some cases your doctor may recommend knee replacement.

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)