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  6. 2026 ICD-10-CM Code M65

2026 ICD-10-CM Diagnosis Code M65

Synovitis and tenosynovitis

ICD-10-CM Code:
M65
ICD-10 Code for:
Synovitis and tenosynovitis
Is Billable?
Not Valid for Submission
Code Navigator:

M65 is a non-specific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of synovitis and tenosynovitis. The code is not specific and is NOT valid for the year 2026 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.

Specific Coding Applicable to Synovitis and tenosynovitis

Non-specific codes like M65 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 synovitis and tenosynovitis:

  • M65.0 for Abscess of tendon sheath - NON-BILLABLE CODE

  • Use M65.00 for Abscess of tendon sheath, unspecified site - BILLABLE CODE

  • M65.01 for Abscess of tendon sheath, shoulder - NON-BILLABLE CODE

  • M65.02 for Abscess of tendon sheath, upper arm - NON-BILLABLE CODE

  • M65.03 for Abscess of tendon sheath, forearm - NON-BILLABLE CODE

  • M65.04 for Abscess of tendon sheath, hand - NON-BILLABLE CODE

  • M65.05 for Abscess of tendon sheath, thigh - NON-BILLABLE CODE

  • M65.06 for Abscess of tendon sheath, lower leg - NON-BILLABLE CODE

  • M65.07 for Abscess of tendon sheath, ankle and foot - NON-BILLABLE CODE

  • Use M65.08 for Abscess of tendon sheath, other site - BILLABLE CODE

  • M65.1 for Other infective (teno)synovitis - NON-BILLABLE CODE

  • Use M65.10 for Other infective (teno)synovitis, unspecified site - BILLABLE CODE

  • M65.11 for Other infective (teno)synovitis, shoulder - NON-BILLABLE CODE

  • M65.12 for Other infective (teno)synovitis, elbow - NON-BILLABLE CODE

  • M65.13 for Other infective (teno)synovitis, wrist - NON-BILLABLE CODE

  • M65.14 for Other infective (teno)synovitis, hand - NON-BILLABLE CODE

  • M65.15 for Other infective (teno)synovitis, hip - NON-BILLABLE CODE

  • M65.16 for Other infective (teno)synovitis, knee - NON-BILLABLE CODE

  • M65.17 for Other infective (teno)synovitis, ankle and foot - NON-BILLABLE CODE

  • Use M65.18 for Other infective (teno)synovitis, other site - BILLABLE CODE

  • Use M65.19 for Other infective (teno)synovitis, multiple sites - BILLABLE CODE

  • M65.2 for Calcific tendinitis - NON-BILLABLE CODE

  • Use M65.20 for Calcific tendinitis, unspecified site - BILLABLE CODE

  • M65.22 for Calcific tendinitis, upper arm - NON-BILLABLE CODE

  • M65.23 for Calcific tendinitis, forearm - NON-BILLABLE CODE

  • M65.24 for Calcific tendinitis, hand - NON-BILLABLE CODE

  • M65.25 for Calcific tendinitis, thigh - NON-BILLABLE CODE

  • M65.26 for Calcific tendinitis, lower leg - NON-BILLABLE CODE

  • M65.27 for Calcific tendinitis, ankle and foot - NON-BILLABLE CODE

  • Use M65.28 for Calcific tendinitis, other site - BILLABLE CODE

  • Use M65.29 for Calcific tendinitis, multiple sites - BILLABLE CODE

  • M65.3 for Trigger finger - NON-BILLABLE CODE

  • Use M65.30 for Trigger finger, unspecified finger - BILLABLE CODE

  • M65.31 for Trigger thumb - NON-BILLABLE CODE

  • M65.32 for Trigger finger, index finger - NON-BILLABLE CODE

  • M65.33 for Trigger finger, middle finger - NON-BILLABLE CODE

  • M65.34 for Trigger finger, ring finger - NON-BILLABLE CODE

  • M65.35 for Trigger finger, little finger - NON-BILLABLE CODE

  • Use M65.4 for Radial styloid tenosynovitis [de Quervain] - BILLABLE CODE

  • M65.8 for Other synovitis and tenosynovitis - NON-BILLABLE CODE

  • Use M65.80 for Other synovitis and tenosynovitis, unspecified site - BILLABLE CODE

  • M65.81 for Other synovitis and tenosynovitis, shoulder - NON-BILLABLE CODE

  • M65.82 for Other synovitis and tenosynovitis, upper arm - NON-BILLABLE CODE

  • M65.83 for Other synovitis and tenosynovitis, forearm - NON-BILLABLE CODE

  • M65.84 for Other synovitis and tenosynovitis, hand - NON-BILLABLE CODE

  • M65.85 for Other synovitis and tenosynovitis, thigh - NON-BILLABLE CODE

  • M65.86 for Other synovitis and tenosynovitis, lower leg - NON-BILLABLE CODE

  • M65.87 for Other synovitis and tenosynovitis, ankle and foot - NON-BILLABLE CODE

  • Use M65.88 for Other synovitis and tenosynovitis, other site - BILLABLE CODE

  • Use M65.89 for Other synovitis and tenosynovitis, multiple sites - BILLABLE CODE

  • M65.9 for Synovitis and tenosynovitis, unspecified - NON-BILLABLE CODE

  • Use M65.90 for Unspecified synovitis and tenosynovitis, unspecified site - BILLABLE CODE

  • M65.91 for Unspecified synovitis and tenosynovitis, shoulder - NON-BILLABLE CODE

  • M65.92 for Unspecified synovitis and tenosynovitis, upper arm - NON-BILLABLE CODE

  • M65.93 for Unspecified synovitis and tenosynovitis, forearm - NON-BILLABLE CODE

  • M65.94 for Unspecified synovitis and tenosynovitis, hand - NON-BILLABLE CODE

  • M65.95 for Unspecified synovitis and tenosynovitis, thigh - NON-BILLABLE CODE

  • M65.96 for Unspecified synovitis and tenosynovitis, lower leg - NON-BILLABLE CODE

  • M65.97 for Unspecified synovitis and tenosynovitis, ankle and foot - NON-BILLABLE CODE

  • Use M65.98 for Unspecified synovitis and tenosynovitis, other site - BILLABLE CODE

  • Use M65.99 for Unspecified synovitis and tenosynovitis, multiple sites - BILLABLE CODE

Code Classification

  • Diseases of the musculoskeletal system and connective tissue
    M00–M99
    • Disorders of synovium and tendon
      M65-M67
      • Synovitis and tenosynovitis
        M65

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 1 Excludes

Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
  • chronic crepitant synovitis of hand and wrist M70.0
  • current injury - see injury of ligament or tendon by body region
  • soft tissue disorders related to use, overuse and pressure M70

Patient Education


Arthritis

What is arthritis?

If you feel pain and stiffness in your body or have trouble moving around, you might have arthritis. Any disorder that affects the joints is often called arthritis. Joints are places where two bones meet, such as your elbow or knee.

Most types of arthritis can cause joint pain and inflammation (swelling). Over time, a swollen joint can become severely damaged. Some kinds of arthritis can also cause problems in your organs, such as your eyes or skin. Treatment will depend on the type of arthritis you have.

What are the types of arthritis?

Common types of arthritis include:

  • Osteoarthritis is the most common type of arthritis. It's often related to aging or injury.
  • Autoimmune arthritis happens when your body's immune system attacks healthy cells in your body by mistake. Rheumatoid arthritis is the most common form of this type of arthritis.
  • Juvenile arthritis is a type of arthritis that happens in children.
  • Infectious arthritis is an infection that has spread from another part of your body to the joint. Reactive arthritis is one type.
  • Psoriatic arthritis affects people with psoriasis (itchy or sore scaly red and white skin patches).
  • Gout is a painful type of arthritis that happens when too much uric acid builds up in your body. It often starts in the big toe. Other joints can also be affected.
  • Ankylosing spondylitis is a type of arthritis of the spine that can cause stiffness and make it difficult to move and bend.

What are the symptoms of arthritis?

Pain, redness, warmth, and joint inflammation are common arthritis symptoms. You may not be able to move your joint as well as it should. Other symptoms could include fever, weight loss, breathing difficulties, or a rash.

Symptoms often get worse as you age. Some symptoms of arthritis may be signs of other illnesses.

Who is more likely to get arthritis?

A few things that might increase your chance of getting arthritis include:

  • Family history. You may be more likely to get certain types of arthritis if a member of your family has the disorder.
  • Age. The risk of getting many types of arthritis increases with age.
  • Sex. Certain types of arthritis are more common in women, while other types are more common in men.

Other factors that might increase your risk of getting arthritis include having a previous joint injury, obesity, or lupus.

How is arthritis diagnosed?

To find out if you have arthritis, your health care provider may:

  • Ask you about your medical history, including your symptoms.
  • Do a physical exam.
  • Order blood tests or take x-rays.

Your provider may refer you to a rheumatologist (a doctor who specializes in arthritis care) for tests, diagnosis, and care.

What are the treatments for arthritis?

Treatment depends on the type of arthritis you have. It may include medicine or surgery. Your provider will work with you to improve your symptoms and quality of life.

A few ways to help manage your symptoms include:

  • Hot or cold packs
  • Relaxation techniques
  • Use of splints, braces, and/or assistive devices

NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases


[Learn More in MedlinePlus]

Connective Tissue Disorders

Your connective tissue supports many different parts of your body, such as your skin, eyes, and heart. It is like a "cellular glue" that gives your body parts their shape and helps keep them strong. It also helps some of your tissues do their work. It is made of many kinds of proteins. Cartilage and fat are types of connective tissue.

Over 200 disorders that impact connective tissue. There are different types:

  • Genetic disorders, such as Ehlers-Danlos syndrome, Marfan syndrome, and osteogenesis imperfecta
  • Autoimmune disorders, such as lupus and scleroderma
  • Cancers, like some types of soft tissue sarcoma

Each disorder has its own symptoms and needs different treatment.

NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases


[Learn More in MedlinePlus]

Code History

  • FY 2026 - No Change, effective from 10/1/2025 through 9/30/2026
  • FY 2025 - No Change, effective from 10/1/2024 through 9/30/2025
  • 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.