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  5. M66
  6. 2024 ICD-10-CM Code M66.3
Version 2024
Non-Billable Code

2024 ICD-10-CM Diagnosis Code M66.3

Spontaneous rupture of flexor tendons

ICD-10-CM Code:
M66.3
ICD-10 Code for:
Spontaneous rupture of flexor tendons
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)

M66.3 is a non-specific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of spontaneous rupture of flexor tendons. 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 Spontaneous rupture of flexor tendons

Non-specific codes like M66.3 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 spontaneous rupture of flexor tendons:

  • Use M66.30 for Spontaneous rupture of flexor tendons, unspecified site - BILLABLE CODE

  • M66.31 for Spontaneous rupture of flexor tendons, shoulder - NON-BILLABLE CODE

  • Use M66.311 for Spontaneous rupture of flexor tendons, right shoulder - BILLABLE CODE

  • Use M66.312 for Spontaneous rupture of flexor tendons, left shoulder - BILLABLE CODE

  • Use M66.319 for Spontaneous rupture of flexor tendons, unspecified shoulder - BILLABLE CODE

  • M66.32 for Spontaneous rupture of flexor tendons, upper arm - NON-BILLABLE CODE

  • Use M66.321 for Spontaneous rupture of flexor tendons, right upper arm - BILLABLE CODE

  • Use M66.322 for Spontaneous rupture of flexor tendons, left upper arm - BILLABLE CODE

  • Use M66.329 for Spontaneous rupture of flexor tendons, unspecified upper arm - BILLABLE CODE

  • M66.33 for Spontaneous rupture of flexor tendons, forearm - NON-BILLABLE CODE

  • Use M66.331 for Spontaneous rupture of flexor tendons, right forearm - BILLABLE CODE

  • Use M66.332 for Spontaneous rupture of flexor tendons, left forearm - BILLABLE CODE

  • Use M66.339 for Spontaneous rupture of flexor tendons, unspecified forearm - BILLABLE CODE

  • M66.34 for Spontaneous rupture of flexor tendons, hand - NON-BILLABLE CODE

  • Use M66.341 for Spontaneous rupture of flexor tendons, right hand - BILLABLE CODE

  • Use M66.342 for Spontaneous rupture of flexor tendons, left hand - BILLABLE CODE

  • Use M66.349 for Spontaneous rupture of flexor tendons, unspecified hand - BILLABLE CODE

  • M66.35 for Spontaneous rupture of flexor tendons, thigh - NON-BILLABLE CODE

  • Use M66.351 for Spontaneous rupture of flexor tendons, right thigh - BILLABLE CODE

  • Use M66.352 for Spontaneous rupture of flexor tendons, left thigh - BILLABLE CODE

  • Use M66.359 for Spontaneous rupture of flexor tendons, unspecified thigh - BILLABLE CODE

  • M66.36 for Spontaneous rupture of flexor tendons, lower leg - NON-BILLABLE CODE

  • Use M66.361 for Spontaneous rupture of flexor tendons, right lower leg - BILLABLE CODE

  • Use M66.362 for Spontaneous rupture of flexor tendons, left lower leg - BILLABLE CODE

  • Use M66.369 for Spontaneous rupture of flexor tendons, unspecified lower leg - BILLABLE CODE

  • M66.37 for Spontaneous rupture of flexor tendons, ankle and foot - NON-BILLABLE CODE

  • Use M66.371 for Spontaneous rupture of flexor tendons, right ankle and foot - BILLABLE CODE

  • Use M66.372 for Spontaneous rupture of flexor tendons, left ankle and foot - BILLABLE CODE

  • Use M66.379 for Spontaneous rupture of flexor tendons, unspecified ankle and foot - BILLABLE CODE

  • Use M66.38 for Spontaneous rupture of flexor tendons, other site - BILLABLE CODE

  • Use M66.39 for Spontaneous rupture of flexor tendons, multiple sites - BILLABLE CODE

Patient Education


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


[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.