What is different with ICD-10?

ICD-9 to ICD-10

More than an update, a leap in how we define care.

Modern History of the Medical Dictionary—ICD-10

The World Health Organization’s (WHO) International Classification of Diseases has served the healthcare community for over a century. The United States implemented the current version (ICD-9) in 1979. While most industrialized countries moved to ICD-10 several years ago, the United States transitioned with a final compliance date of October 1, 2015. It’s time our Medical Dictionary reflected modern medicine.

By Physicians for Physicians

Under the sponsorship of the WHO, a select group of physicians created the basic ICD-10 structure. Following this, each physician specialty within the United States offered their input on the subset of diagnosis codes required. In most cases, the specialties advocated capturing additional detail based on information that physicians intuitively use in delivering patient care. These changes enhance current medical documentation standards to capture a greater level of detail in patient care. Accurate analysis of health data will help improve the quality and efficiency of delivering patient care, particularly as electronic sharing and exchange of health records grows.

The Differences will make a Difference

It is important to understand the major improvements and changes between ICD-9 and ICD-10 diagnosis codes.
ICD-9-CM Diagnosis Codes ICD-10-CM Diagnosis Codes
No Laterality Laterality – Right or Left account for >40% of codes
3-5 digits
  • First digit is alpha (E or V) or numeric
  • Digits 2-5 are numeric
  • Decimal is placed after the third character
7 digits
  • Digit 1 is alpha; Digit 2 is numeric
  • Digits 3–7 are alpha or numeric
  • Decimal is placed after the third character
No placeholder characters “X” placeholders
14,000 codes 69,000 codes to better capture specificity
Limited Severity Parameters Extensive Severity Parameters
Limited Combination Codes Extensive Combination Codes to better capture complexity
1 type of Excludes Notes 2 types of Excludes Notes
Figure One: Femur Fracture Example illustrates the major differences between the ICD-9 and ICD-10 code structure.

Figure One: Femur Fracture Example

ICD-9 ICD-10
X-ray of Left Femur Fracture

Before the Compliance Date

821.11 Open fracture of Shaft of Femur

All codes for femur fracture = 16

X-ray of Left Femur Fracture

After the Compliance Date

S72.352C Displaced comminuted fracture of shaft of left femur, initial encounter for open fracture type IIIA, IIIB, or IIIC

All codes for femur fracture = 1530

Other Important Changes to Note in ICD-10-CM:

  • Importance of Anatomy: Injuries are grouped by anatomical site rather than by type of injury
  • Incorporation of E and V Codes: The codes corresponding to ICD-9-CM V codes (Factors Influencing Health Status and Contact with Health Services) and E codes (External Causes of Injury and Poisoning) are incorporated into the main classification rather than separated into supplementary classifications as they were in ICD-9-CM
  • New Definitions: In some instances, new code definitions are provided reflecting modern medical practice (e.g., definition of acute myocardial infarction is now 4 weeks rather than 8 weeks)
  • Restructuring and Reorganization: Category restructuring and code reorganization have occurred in a number of ICD-10-CM chapters, resulting in the classification of certain diseases and disorders that are different from ICD-9-CM
  • Reclassification: Certain diseases have been reclassified to different chapters or sections in order to reflect current medical knowledge
To learn more about ICD-10 and the changes surrounding the transition, please visit http://www.cms.gov/Medicare/Coding/ICD10/downloads/ICD-10MythsandFacts.pdf.