Seven dwarves; seven world wonders; 7-Up. These are all totally non-threatening—some might even say smile-inducing—associations with the number seven. ICD-10’s seventh character, on the other hand, has caused a lot of frowns—or, at the very least, furrowed brows—among those in the healthcare community. And that’s especially true for physical therapists. Here, I’ve compiled a list of seven seventh-character must-knows:

1. There’s no ICD-9 equivalent of the seventh character.

ICD-9 caps its codes at five characters, meaning seventh characters physically cannot exist in the old code set. Furthermore, ICD-9 does not provide any mechanism to capture the details indicated by ICD-10’s seventh character. And that is precisely why it’s such a point of confusion. While most providers document the information that the seventh character communicates, they’ve never had to actually code for it. So this is not a simple swap-this-character-for-that-one situation; it’s totally new territory.

2. Typically, PTs will use one of three seventh character options.

These three seventh characters provide details related to the plan of care—specifically, the type of encounter for the date of service on a particular claim:

A – Initial encounter

This means the patient is receiving active treatment for his or her injury or condition.

D – Subsequent encounter

This means that the active phase of treatment for the patient’s injury or condition has ended, and that the patient is now in the healing or recovering phase of treatment.

S – Sequela

This less frequently-used character is reserved for complications or conditions directly resulting from an injury. A commonly used example of a sequela is a scar that results from a burn.

3. There’s a whole separate set of seventh characters for fracture codes.

Many PTs will come across fracture codes for physician-referred patients, so it’s important that they at least understand how the seventh character system works for these codes. Here’s the breakdown of the super-specific seventh characters reserved for fracture codes:

  • A – Initial encounter for closed fracture.
  • B – Initial encounter for open fracture.
  • D – Subsequent encounter for fracture with routine healing.
  • G – Subsequent encounter for fracture with delayed healing.
  • K – Subsequent encounter for fracture with nonunion.
  • P – Subsequent encounter for fracture with malunion.
  • S – Sequela.

Furthermore, some categories of fracture codes require seventh characters from a whole other list—one that is even more specific. This list, which contains 16 seventh character options, is detailed in this blog post from the American Academy of Professional Coders (AAPC). The post also explains that following the transition to ICD-10, providers will no longer use fracture aftercare codes like the ones used in ICD-9. Instead, when coding for traumatic fracture aftercare, they’ll “assign the acute fracture code with the appropriate seventh character.”   

4. Not all codes allow for seventh characters.

You can’t add a seventh character to just any ol’ code in the book. In fact, putting a seventh character on a code that does not require one would result in an invalid code—and thus, an almost certain claim denial. Conversely, not adding a seventh character to a code that does require one also would result in denial. Bottom line: Check the instructions at the beginning of each section of codes to determine whether you need to code all the way to the last character.

5. Most of the PT-related codes that require seventh characters are located in Chapter 19.

According to this blog post, “You must assign a seventh character to codes in certain ICD-10-CM categories as noted within the Tabular List of codes—primarily Chapter 19 (Injury, poisoning and certain other consequences of external causes) and Chapter 15 (Pregnancy, childbirth and the puerperium).” Most PTs won’t deal with Chapter 15 too often, but they’ll likely use Chapter 19—a.k.a. the injury chapter—pretty frequently. So, if you’ve landed on an injury code that you intend to submit on a claim, you better review the instructions at the beginning of the section that contains the code. If you need to attach a seventh character, you’ll see guidelines similar to these, which appear at the beginning of the S56 category (Injury of muscle, fascia, and tendon at forearm level):

The appropriate 7th character is to be added to each code from category S56

A – initial encounter
D – subsequent encounter
S – sequela

6. A placeholder “X” must occupy each empty space that precedes the seventh character.

If you’re adding a seventh character to a code that contains five or fewer characters, you must enter an “X” in each empty character slot between the final character of the root code and its associated seventh character. Essentially, these X’s form a chain that connects the code to its seventh character. Without them, the seventh character looks like an orphan with no home, and the code will appear incomplete to the claim processor.

Here’s an example: Let’s say you’re coding for a patient with a sprained superior tibiofibular joint and ligament in the patient’s right knee. The correct diagnosis code would be S83.61. And at the beginning of the S83 section of codes, you see instructions to add a seventh character. So, let’s assume the patient is in the active phase of treatment for this injury. That means you need to add the seventh character “A,” but because the original code only contains five characters, you also need to add a placeholder “X” before you attach the “A.” Thus, your final code would be S83.61XA.

7. There’s still a lot of confusion as to what separates an “initial encounter” from a “subsequent encounter.”

Here at WebPT, we’ve received a lot of questions from PTs who are utterly confused about when—if ever—they should code for an initial encounter. And our quest to find concrete guidance on that conundrum has turned up a variety of conflicting answers, some of which we are still trying to sort out with our coding experts. But based on everything we’ve reviewed, this is the best answer we’ve found, and it comes directly from CMS: “The 7th character for ‘initial encounter’ is not limited solely to the very first encounter for a new condition. This 7th character can be used for multiple encounters as long as the patient continues to receive active treatment for the condition.” This resource goes on to say, “The key to assignment of the 7th character for initial encounter is whether the patient is still receiving active treatment for that condition.”

So, it appears that the words “initial” and “subsequent” have less to do with how many practitioners the patient has already seen or how many visits the patient has logged at your office—and more to do with what phase of treatment the patient is in. If the patient is still in the active phase of treatment for his or her diagnosis, then the correct seventh character would be “A.” If the patient is now recovering/healing from the injury or condition indicated by the diagnosis, then the correct seventh character would be “D.” By that definition—just to reiterate the above-cited advice from CMS—the seventh character “A” is not limited to the patient’s first visit, even though the label “initial encounter” makes it seem like a one-time descriptor.

All of that being said, the majority of PT encounters likely will fall into the “D” category, as patients often are in the healing and recovery phase of their diagnoses by the time they start rehabilitation treatment. However, therapists must use their clinical judgement to make that call.


Still feeling like seven isn’t your lucky number? What questions do you have? Let us know in the comment section below.