M21.7 - Unequal limb length (acquired)

Version 2023
ICD-10:M21.7
Short Description:Unequal limb length (acquired)
Long Description:Unequal limb length (acquired)
Status: Not Valid for Submission
Version:ICD-10-CM 2023
Code Classification:
  • Diseases of the musculoskeletal system and connective tissue (M00–M99)
    • Other joint disorders (M20-M25)
      • Other acquired deformities of limbs (M21)

M21.7 is a non-specific and non-billable ICD-10 code code, consider using a code with a higher level of specificity for a diagnosis of unequal limb length (acquired). The code is not specific and is NOT valid for the year 2023 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 for Unequal limb length (acquired)

Non-specific codes like M21.7 require more digits to indicate the appropriate level of specificity. Consider using any of the following ICD-10 codes with a higher level of specificity when coding for unequal limb length (acquired):

  • BILLABLE CODE - Use M21.70 for Unequal limb length (acquired), unspecified site
  • NON-BILLABLE CODE - M21.72 for Unequal limb length (acquired), humerus
  • BILLABLE CODE - Use M21.721 for Unequal limb length (acquired), right humerus
  • BILLABLE CODE - Use M21.722 for Unequal limb length (acquired), left humerus
  • BILLABLE CODE - Use M21.729 for Unequal limb length (acquired), unspecified humerus
  • NON-BILLABLE CODE - M21.73 for Unequal limb length (acquired), ulna and radius
  • BILLABLE CODE - Use M21.731 for Unequal limb length (acquired), right ulna
  • BILLABLE CODE - Use M21.732 for Unequal limb length (acquired), left ulna
  • BILLABLE CODE - Use M21.733 for Unequal limb length (acquired), right radius
  • BILLABLE CODE - Use M21.734 for Unequal limb length (acquired), left radius
  • BILLABLE CODE - Use M21.739 for Unequal limb length (acquired), unspecified ulna and radius
  • NON-BILLABLE CODE - M21.75 for Unequal limb length (acquired), femur
  • BILLABLE CODE - Use M21.751 for Unequal limb length (acquired), right femur
  • BILLABLE CODE - Use M21.752 for Unequal limb length (acquired), left femur
  • BILLABLE CODE - Use M21.759 for Unequal limb length (acquired), unspecified femur
  • NON-BILLABLE CODE - M21.76 for Unequal limb length (acquired), tibia and fibula
  • BILLABLE CODE - Use M21.761 for Unequal limb length (acquired), right tibia
  • BILLABLE CODE - Use M21.762 for Unequal limb length (acquired), left tibia
  • BILLABLE CODE - Use M21.763 for Unequal limb length (acquired), right fibula
  • BILLABLE CODE - Use M21.764 for Unequal limb length (acquired), left fibula
  • BILLABLE CODE - Use M21.769 for Unequal limb length (acquired), unspecified tibia and fibula

Tabular List of Diseases and Injuries

The Tabular List of Diseases and Injuries is a list of ICD-10 codes, organized "head to toe" into chapters and sections with coding notes and guidance for inclusions, exclusions, descriptions and more. The following references are applicable to this diagnosis code:


Patient Education


Bone Diseases

Your bones help you move, give you shape and support your body. They are living tissues that rebuild constantly throughout your life. During childhood and your teens, your body adds new bone faster than it removes old bone. After about age 20, you can lose bone faster than you make bone. To have strong bones when you are young, and to prevent bone loss when you are older, you need to get enough calcium, vitamin D, and exercise. You should also avoid smoking and drinking too much alcohol.

Bone diseases can make bones easy to break. Different kinds of bone problems include:

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Code History