ICD-10 Code Structure and Expansion Logic

This help page provides information on the ICD-10 code structure and NextGen Office’s ICD-10 code expansion logic.

Note: October 1,  2015 is the mandatory compliance date to use ICD-10 codes in place of ICD-9 codes for diagnosis coding.

ICD-10 Code Structure

ICD-10 diagnosis codes can have 3-7 characters. Three-character codes describe the diagnosis category. As more characters are added to the code, the more specific the code becomes.

Note: We do not display the decimal point that separates the first three characters from the rest of the characters in the ICD-10 code.

Some codes, like the following example, require all seven characters to be a billable code. In this example, we break down the ICD-10 code structure of an initial encounter for a right ankle sprain.

• Category (code family) – S93: Dislocation and sprain of joints and ligaments at ankle, foot, and toe level
• Add more specificity to indicate the ankle – S93.4: Sprain of ankle
• Add more specificity to indicate which ligament – S93.42: Sprain of deltoid ligament
• Add more specificity to indicate which ankle – S93.421: Sprain of deltoid ligament of right ankle
• Add more specificity to indicate the encounter type – S93.421A: Sprain of deltoid ligament of right ankle, initial encounter

Some Differences from ICD-9

Laterality

ICD-10 codes can indicate laterality (side of the body affected). When the diagnosis requires laterality, it is described in the code’s sixth character.

• 1 = Right side
• 2 = Left side
• 3 = Bilateral
• 9 = Unspecified
• 0 = Extremity-related and certain other diagnoses use 0 instead of 9

 

Seventh Character Extension

Certain codes require characteristic data about the encounter. This is expressed in the seventh character extension. When required, you must use an extension character for the code to be valid. Injuries is one chapter that uses the seventh character extension; the following are the extensions for injuries.

• A = Initial encounter
• D = Subsequent encounter
• S = Sequela

 

Dummy Placeholder

• A dummy placeholder (“x”) is used to allow for future code expansion (e.g., T370x1A) and/or fill empty characters when a code has fewer than six characters and a seventh character is required (e.g., T790xxA).
• If a dummy placeholder is required, you must use an “x” as a placeholder for the code to be valid.

ICD-10 Code Expansion Logic

One way to understand NextGen Office’s ICD-10 code expanding logic is to think of the codes as parts of a family tree. Any branching out from the selected code on the tree follows a particular path. We provide three buttons to expand the selected code’s search results.

• : Displays the sibling codes of the immediate family of codes.
• : Displays the cousin codes of the extended family of codes.
• Show More: Displays the parent (if it is billable) of the selected code and the parent’s descendants. Continues to display parents farther up the family tree and their descendants until there are no more billable codes. Search stops at the first three characters (e.g., J01).
• Diagnosis category J01 is used to elaborate on our ICD-10 expansion logic.

• Each four-character code indicated in bold are parent codes (e.g., J010).
• The left side of the screen capture shows the search results for J0100 after clicking  (the results are indicated in blue). Each set of codes beneath each parent are children (e.g., J0100 and J0101) and the members of each set are siblings to each other.
• The center of the screen capture shows the search results for J0100 after clicking  (the results are indicated in blue). Each blue code has different parent codes and are therefore cousins to each other.
• The right side of the screen capture shows the search results for J0100 after clicking Show More. Each blue code indicated is a descendant of J0100’s parent code (J010).

Wildcard Searches

Every time you click one of the expansion options, you are performing a wildcard search. A wildcard search substitutes one or more characters in a search query. We use an asterisk (*) to indicate where the wildcard character is. The following sections describe what occurs when you click any of the ICD-10 code expansion options.

 

• Navigate to Diagnosis Coding  in an encounter (click A in the SOAP menu).
• Enter J01 in the search box. The search returns everything that contains J01*.

 Expansion

 

• J0100 is used in this example.
• Click .
• This searches all codes using the last character as the wildcard character (in this example, it is the fifth character).
• The performed search is J010* and it returns all codes that begin with J010 (shown in blue).

 Expansion

 

• Click .
• This searches all codes using the second to the last character as the wildcard character (in this example, it is the fourth character).
• The performed search is J01*0 and it returns all codes that contain J01*0 (shown in blue).

Show More

 

• You must click  to activate the Show More button.
• Click Show More. This search eliminates the last character in the search and uses the second to the last character as the wildcard character.
• The search that is performed is J01* and it returns all codes that contain J01 (shown in blue).
• If there are no billable codes at the parent level of the code, the displayed codes do not change.

 

• Note: For longer codes, the Show More button continues to be an option until there are no more billable parent-level codes (or their descendants) to display and/or the search reaches the first three characters.
• S93401A is used as the example. The first Show More search is S9340*.
• The characters boxed in red are the only characters that differ.

 

• Click Show More again. The wildcard character in the second Show More search shifts one character to the left. The performed search is S934*.
• The characters boxed in red are the only characters that differ.
• S93401A appears in all of the Show More search results since it is a descendant regardless of how far up the family tree we search. It is not shown here so we can display different results from the previous search.

 

• Click Show More again. The wildcard character in the third Show More search shifts one character to the left. The performed search is S93*.
• The characters boxed in red are the only characters that differ.
• The Show More button is no longer an option since the search has reached the first three characters.