Version 2024

2024 ICD-10-CM Diagnosis Code M66.1

Rupture of synovium

ICD-10-CM Code:
M66.1
ICD-10 Code for:
Rupture of synovium
Is Billable?
Not Valid for Submission
Code Navigator:

Code Classification

  • Diseases of the musculoskeletal system and connective tissue
    (M00–M99)
    • Disorders of synovium and tendon
      (M65-M67)
      • Spontaneous rupture of synovium and tendon
        (M66)

M66.1 is a non-specific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of rupture of synovium. The code is not specific and is NOT valid for the year 2024 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 Rupture of synovium

Non-specific codes like M66.1 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 rupture of synovium:

  • Use M66.10 for Rupture of synovium, unspecified joint - BILLABLE CODE

  • M66.11 for Rupture of synovium, shoulder - NON-BILLABLE CODE

  • Use M66.111 for Rupture of synovium, right shoulder - BILLABLE CODE

  • Use M66.112 for Rupture of synovium, left shoulder - BILLABLE CODE

  • Use M66.119 for Rupture of synovium, unspecified shoulder - BILLABLE CODE

  • M66.12 for Rupture of synovium, elbow - NON-BILLABLE CODE

  • Use M66.121 for Rupture of synovium, right elbow - BILLABLE CODE

  • Use M66.122 for Rupture of synovium, left elbow - BILLABLE CODE

  • Use M66.129 for Rupture of synovium, unspecified elbow - BILLABLE CODE

  • M66.13 for Rupture of synovium, wrist - NON-BILLABLE CODE

  • Use M66.131 for Rupture of synovium, right wrist - BILLABLE CODE

  • Use M66.132 for Rupture of synovium, left wrist - BILLABLE CODE

  • Use M66.139 for Rupture of synovium, unspecified wrist - BILLABLE CODE

  • M66.14 for Rupture of synovium, hand and fingers - NON-BILLABLE CODE

  • Use M66.141 for Rupture of synovium, right hand - BILLABLE CODE

  • Use M66.142 for Rupture of synovium, left hand - BILLABLE CODE

  • Use M66.143 for Rupture of synovium, unspecified hand - BILLABLE CODE

  • Use M66.144 for Rupture of synovium, right finger(s) - BILLABLE CODE

  • Use M66.145 for Rupture of synovium, left finger(s) - BILLABLE CODE

  • Use M66.146 for Rupture of synovium, unspecified finger(s) - BILLABLE CODE

  • M66.15 for Rupture of synovium, hip - NON-BILLABLE CODE

  • Use M66.151 for Rupture of synovium, right hip - BILLABLE CODE

  • Use M66.152 for Rupture of synovium, left hip - BILLABLE CODE

  • Use M66.159 for Rupture of synovium, unspecified hip - BILLABLE CODE

  • M66.17 for Rupture of synovium, ankle, foot and toes - NON-BILLABLE CODE

  • Use M66.171 for Rupture of synovium, right ankle - BILLABLE CODE

  • Use M66.172 for Rupture of synovium, left ankle - BILLABLE CODE

  • Use M66.173 for Rupture of synovium, unspecified ankle - BILLABLE CODE

  • Use M66.174 for Rupture of synovium, right foot - BILLABLE CODE

  • Use M66.175 for Rupture of synovium, left foot - BILLABLE CODE

  • Use M66.176 for Rupture of synovium, unspecified foot - BILLABLE CODE

  • Use M66.177 for Rupture of synovium, right toe(s) - BILLABLE CODE

  • Use M66.178 for Rupture of synovium, left toe(s) - BILLABLE CODE

  • Use M66.179 for Rupture of synovium, unspecified toe(s) - BILLABLE CODE

  • Use M66.18 for Rupture of synovium, other site - BILLABLE CODE

Patient Education


Joint Disorders

What are joints?

Your joints are places where two or more bones come together. Your shoulders, elbows, hips, knees, and knuckles are all joints. Your spine has joints, too.

But joints are more than bones. They include the soft tissues around them, such as cartilage, tendons and ligaments. Cartilage is the hard slippery flexible tissue that covers the ends of your bones at a joint. Tendons are tough, flexible bands that connect your muscles to your bones so you can move your joints. Ligaments connect the bones of the joint to each other to keep them stable when you move.

What are joint disorders?

Joint disorders are diseases or injuries that affect your joints. Injuries can happen because of overuse of a joint. Or you could have a sudden injury, such as an accident or a sports injury.

What diseases can affect the joints?

Many diseases can affect the joints. They often cause joint pain and make your joints stiff, red, or swollen. Most of them are chronic. That means they last a long time. Some may never go away completely. Some of the diseases that affect the joints include:

  • Arthritis. Arthritis may cause joint pain and swelling. There are many types of this disease. Osteoarthritis is the most common type. Over time, arthritis can cause severe joint damage. It can affect people of all ages. A joint injury when you're young may cause osteoarthritis later in life.
  • Lupus. This autoimmune disease affects many parts of the body and can cause joint and muscle pain. Some types of lupus often cause arthritis.
  • Sjögren's Syndrome. This autoimmune disease affects glands that make moisture in many parts of the body. The main symptoms are dry eyes and mouth, but it often causes joint pain, too.

Treatments are different depending on the disease. But most treatments include medicines and therapies to relieve pain and other symptoms.

What types of joint disorders happen from sudden injuries?

Joint disorders from sudden injuries include:

  • Sprains and strains. Sprains are stretched or torn ligaments. Acute strains are stretched or torn muscles or tendons that happen from a sudden injury or movement, such as lifting a heavy object.
  • Dislocated joints. A joint is dislocated when the bones are pushed or pulled out of position. A joint dislocation is a medical emergency.

Treatment depends on the type of injury. You can treat many sports injuries at home. But you should call your health care provider if you:

  • Have a lot of joint pain, swelling or numbness
  • Can't put weight on the joint
  • Have pain from an old injury with more swelling, an unstable joint, or a joint that isn't normal in another way

What types of joint disorders happen from overuse?

Overuse injuries usually damage the soft tissues of the joint. They can happen when you work a joint too hard by doing the same movements over and over. For example, you could get an overuse injury from playing a musical instrument, playing sports, or doing certain jobs, such as carpentry or painting.

Joint overuse injuries include:

  • Bursitis. The bursa is a small fluid-filled sac. It works as a pad between the bones of a joint and the moving parts around it, such as muscles, tendons and skin. With bursitis, the bursa becomes irritated and swollen with extra fluid. Overuse is the most common cause, but injuries, infections and other conditions, such as arthritis, can cause bursitis.
  • Tendinitis. This condition happens when you overuse a tendon. It swells and makes the joint painful to move.
  • Chronic strain. A strain becomes chronic when your muscles or tendons stretch or tear slowly over time from repeating the same movements.

The treatments for bursitis, tendinitis, and chronic strain are often the same. They usually include rest, keeping the injured joint higher than your heart, and taking medicine to reduce swelling. Your provider may recommend gentle exercise and other treatment. In some cases, your provider may suggest an injection (a shot) of medicine into the joint. If these do not help, you may need surgery.

How can I keep my joints healthy?

Getting enough physical activity is one of the most important things you can do to prevent or slow joint disorders. Activity strengthens the muscles around your joints and helps them work better.

When you play sports, wear the right equipment to protect your joints, such as knee pads. If you already have joint problems, ask your provider what type of activities are best for you.

NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases


[Learn More in MedlinePlus]

Code History

  • 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.