ICD-10-CM Code M65.9

Synovitis and tenosynovitis, unspecified

Version 2020 Billable Code

Valid for Submission

M65.9 is a billable code used to specify a medical diagnosis of synovitis and tenosynovitis, unspecified. The code is valid for the year 2020 for the submission of HIPAA-covered transactions. The ICD-10-CM code M65.9 might also be used to specify conditions or terms like chronic synovitis, extensor carpi radialis tenosynovitis, extensor digitorum longus tenosynovitis, extensor hallucis longus tenosynovitis, peroneal tenosynovitis, sapho syndrome, etc

Short Description:Synovitis and tenosynovitis, unspecified
Long Description:Synovitis and tenosynovitis, unspecified

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 M65.9 are found in the index:

  • - Synovitis - See Also: Tenosynovitis; - M65.9


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

  • Chronic synovitis
  • Extensor carpi radialis tenosynovitis
  • Extensor digitorum longus tenosynovitis
  • Extensor hallucis longus tenosynovitis
  • Peroneal tenosynovitis
  • SAPHO syndrome
  • Synovitis
  • Synovitis and tenosynovitis
  • Synovitis AND/OR tenosynovitis associated with another disease
  • Synovitis of ankle
  • Synovitis of left ankle joint
  • Synovitis of right ankle joint
  • Tendon sheath crepitus
  • Tenosynovitis
  • Tenosynovitis of ankle
  • Tenosynovitis of ankle
  • Tenosynovitis of bilateral hands
  • Tenosynovitis of foot
  • Tenosynovitis of foot
  • Tenosynovitis of left ankle
  • Tenosynovitis of left foot
  • Tenosynovitis of left hand
  • Tenosynovitis of right ankle
  • Tenosynovitis of right foot
  • Tenosynovitis of right hand

Diagnostic Related Groups

The ICD-10 code M65.9 is grouped in the following groups for version MS-DRG V37.0 What are Diagnostic Related Groups?
The Diagnostic Related Groups (DRGs) are a patient classification scheme which provides a means of relating the type of patients a hospital treats. The DRGs divides all possible principal diagnoses into mutually exclusive principal diagnosis areas referred to as Major Diagnostic Categories (MDC).
applicable from 10/01/2019 through 09/30/2020.


Convert M65.9 to ICD-9

Code Classification

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

Code History

  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016
    (First year ICD-10-CM implemented into the HIPAA code set)
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020

Information for Patients

Joint Disorders

A joint is where two or more bones come together, like the knee, hip, elbow, or shoulder. Joints can be damaged by many types of injuries or diseases, including

  • Arthritis - inflammation of a joint. It causes pain, stiffness, and swelling. Over time, the joint can become severely damaged.
  • Bursitis - inflammation of a fluid-filled sac that cushions the joint
  • Dislocations - injuries that force the ends of the bones out of position

Treatment of joint problems depends on the cause. If you have a sports injury, treatment often begins with the RICE (Rest, Ice, Compression, and Elevation) method to relieve pain, reduce swelling, and speed healing. Other possible treatments include pain relievers, keeping the injured area from moving, rehabilitation, and sometimes surgery. For arthritis, injuries, or other diseases, you may need joint replacement surgery to remove the damaged joint and put in a new one.

NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases

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Tendons are flexible bands of tissue that connect muscles to bones. They help your muscles move your bones. Tendinitis is the severe swelling of a tendon.

Tendinitis usually happens after repeated injury to an area such as the wrist or ankle. It causes pain and soreness around a joint. Some common forms of tendinitis are named after the sports that increase their risk. They include tennis elbow, golfer's elbow, pitcher's shoulder, swimmer's shoulder, and jumper's knee.

Doctors diagnose tendinitis with your medical history, a physical exam, and imaging tests. The first step in treatment is to reduce pain and swelling. Rest, wrapping or elevating the affected area, and medicines can help. Ice is helpful for recent, severe injuries. Other treatments include ultrasound, physical therapy, steroid injections, and surgery.

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