How to Pick the Correct G83.XX CPT Code

Q: “Code G83.24 Monoplegia of upper limb affecting left non-dominant side. This code is used for diagnosing issues that affect the left side of the person. My question is, due to the non-dominant side, would this make the person left-handed as dominant or right-handed? For example, code G83.23, affecting the right side, but due to non-dominance, the person is left-handed. My question again is, when using G83.24, is the person is right-handed or left-handed?

A: This is so easily confusing and the answer is non-dominant. Whichever side you don’t use (and it’s usually always documented) but the dominant side will be the side that you use for the most of the things.  Think like this, “Do you write with your left hand or your right hand?” that’s going to be your dominant side.  The short answer before we get into the details is it’s going to be in the documentation if it isn’t, there’s a guideline that tells you.  You default to the dominant side being the right-hand side because most people are right-handed.

Going into the explanation now, a little more in-depth, let’s look at the codes more closely. If the person is left-handed, you’re going to use code G83.23, so that would be monoplegia of upper limb affecting the right non-dominant side stating the person is left-handed.  Say, they write with their left hand (dominant), and the stroke was on the left side, this affects the right side, the right hand which is non-dominant because they’re left-handed.

Now, if the person is right-handed (dominant), meaning that “I write with my right hand. The stroke happened on the right side, this affects the opposite side of the body, my left non-dominant side, code is G83.24.” 

An example of that I wrote. Mrs.Green – I love using colors – suffered a stroke. Her daughter started her mother was left-handed. Exam reveals she has monoplegia of the right hand. So what, she’s left-handed, “I write with my left hand and the stroke has affected my right side, that’s my non-dominant side.”  the code would be then G83.23 – monoplegia of the upper left limb affecting the right non-dominant side.

At other times you do not know which side is the deficit, left or right. Many times this happens a person comes in with a stroke, you don’t know, if they can talk or not in that case, you will use code G83.20 – monoplegia of upper limb affecting unspecified side. Meaning, we don’t know if it’s right or left dominant. You don’t want to use this code all the time because you are supposed to default, so right-handed. If we know the person is right-handed, G83.21 – monoplegia of upper limb affecting right dominant side – right-handed, right side. Left-handed, G83.22 – monoplegia of upper limb affecting left dominant side.

What do you code when you do not know which limb is dominant? 

You got to know which limb is affected not in all cases but this is your guideline, straight from the guidelines. It’s in chapter 6. It tells you that you have some choices. For an ambidextrous patient – my mother is ambidextrous, she paints two paintings at one time – the default should be dominant. Both sides are dominant. If the left- side is affected, then you default to non-dominant because most people are right-handed. Then if the right side is affected, you default to dominant, because we know that most people are right-handed. Then last, that was just pulled up from the Carol Buck. I got it from my Elsevier manual. There you go. I did it two minutes over.

Understanding Dominant and Non-Dominant Sides

What is code G83.24, Monoplegia of upper limb affecting left non-dominant side, used for? This code is used for diagnosing issues that affect the left side of the person. The question is, due to the non-dominant side, would this make the person left-handed as dominant or right-handed? For example, code G83.23 is affecting the right side, but due to non-dominance, the person is left-handed. One question is; when using G83.24, is the person right-handed or left-handed?

This is easily confusing and the answer is non-dominant. Whichever side you don’t use (and it’s usually always documented). The dominant side will be the side that you use for most things. Visualize this, “Do you write with your left hand or your right hand?” That’s going to be your dominant side.  The short answer, before we get into the details, is it’s going to be in the documentation, if it isn’t, there’s a guideline that tells you.  You default to the dominant side being the right-hand side because most people are right-handed.

Guideline I.C.6.A reads “Dominant/nondominant side – Codes from category G81, Hemiplegia, and hemiparesis, and subcategories G83.1, Monoplegia of lower limb, G83.2, Monoplegia of upper limb, and G83.3, Monoplegia, unspecified, identify whether the dominant or non-dominant side is affected. Should the affected side be documented, but not specified as dominant or non-dominant, and the classification system does not indicate a default code selection is as follows:

• For ambidextrous patients, the default should be dominant.
• If the left side is affected, the default is non-dominant.
• If the right side is affected, the default is dominant.

Going into the explanation now, a little more in-depth, let’s look at the codes more closely. If the person is left-handed, you’re going to use code G83.23 – Monoplegia of upper limb affecting right non-dominant side stating the person is left-handed.  Say, they write with their left hand (dominant), and the stroke was on the left side, this affects the right side, the right hand which is non-dominant because they’re left-handed.

If the person is right-handed (dominant), meaning that “I write with my right hand. The stroke happened on the right side, this affects the opposite side of the body, my left non-dominant side, code is G83.24.” 

Here is an example. Mrs.Green suffered a stroke. Her daughter stated her mother was left-handed. Exam reveals she has monoplegia of the right hand. She’s left-handed, “I write with my left hand and the stroke has affected my right side, that’s my non-dominant side.”  The code would then be G83.23 – monoplegia of the upper left limb affecting the right non-dominant side.

At other times you do not know which side is the deficit, left or right. Many times this happens a person comes in with a stroke, you don’t know, if they can’t talk, you will use code G83.20 – monoplegia of upper limb affecting unspecified side. Meaning, we don’t know if it’s right or left dominant. You don’t want to use this code all the time because you are supposed to default to right-handed.