Orthopedic Coding Alert

Hip/knee osteoarthritis most common for many ortho practices.

Patients often report to the orthopedist to manage symptoms caused by osteoarthritis (OA). The majority of OA patients suffer from the condition in the hip and knees — though you can also find it in other anatomical locations.

“In an orthopedic specialty care practice specifically, arthritis is a condition we treat daily. We see Arthritis develop throughout joints in the whole body but the most common arthritis we manage is found in the knee & hip,” explains Kaitlyn Bohrer, COSC, of Eastside Orthopedics & Sports Medicine in Milwaukie, Oregon.

A major challenge when coding OA patients is deciding which type of OA the patient has, and to do that you need more than anatomical knowledge. Read on for advice on hitting the mark for each of your OA patients.

Remember The OA Types

For coding purposes, there are six different types of OA. Check out this expert input on identifying each type.

Polyosteoarthritis: Leading off the OA code set is this condition, in which OA is present in multiple sites. Polyosteoarthritis codes are different from other OA codes; they’re only four characters, and don’t go into great detail.

The good news is that you’ll only have to identify the polyosteoarthritis type to complete your ICD-10 coding. The polyosteoarthritis codes are:

• M15.0 (Primary generalized (osteo)arthritis)
• M15.1 (Heberden’s nodes (with arthropathy))
• M15.2 (Bouchard’s nodes (with arthropathy))
• M15.3 (Secondary multiple arthritis)
• M15.4 (Erosive (osteo)arthritis)
• M15.8 (Other polyosteoarthritis)
• M15.9 (Polyosteoarthritis, unspecified)

Example: Notes indicate that the orthopedist treated a patient with Bouchard’s nodes. For this patient, you’ll report M15.2.

Primary osteoarthritis: This type of OA “develops over time with degeneration, inflammation, and just plain wear and tear to the joint,” explains Kaitlyn Bohrer, COSC, of Eastside Orthopedics & Sports Medicine in Milwaukie, Oregon.

Secondary osteoarthritis: Primary OA occurs just due to wear and tear, but secondary OA “is caused by a known reason or consequence. A primary condition or diagnosis you may find attached to secondary OA is mostly contributory to underlying conditions such as obesity, genetics, inactivity, and a large inventory of other diseases,” explains Bohrer.

Posttraumatic osteoarthritis: Posttraumatic OA is a subtype of secondary OA. The condition “is contributory to a particular trauma or injury such as a subsequent fracture to a bone after playing a sport or an injury due to a car accident,” says Bohrer.

Dysplastic osteoarthritis: This OA type, specific to the hips, “is caused by the hip not being in alignment. It wears down the cartilage and after time leads to osteoarthritis in the joint,” according to Alicia Scott CPC, CPC-I, CRC, director of education for CCO.us.

“Dysplasia of the hip ultimately causes the hip joint to become partially or completely dislocated from the socket; this occurs when the socket portion does not fully cover the ball portion of the upper thighbone. The condition is largely developmental and has a high risk of dysplastic arthritis because of the constant depletion of the smooth cartilage on the bones that helps them glide fluently against each,” Bohrer continues.

Other osteoarthritis: Other OA is what you assign OA when “the provider has identified specificity; however, there is not a code for [the OA identified] at this time,” says Scott.

Get to Know Hip/Knee Codes

The OA codes that will likely get the most work in your ortho practice are for hip and knee OA. They’re also the group that takes up most of the space in the OA section of ICD-10. Here’s a look at how granular these codes can get:

Hip

• M16.0 (Bilateral primary osteoarthritis of hip)
• M16.1- (Unilateral primary osteoarthritis of hip)
• M16.2 (Bilateral osteoarthritis resulting from hip dysplasia)
• M16.3- (Unilateral osteoarthritis resulting from hip dysplasia)
• M16.4 (Bilateral post-traumatic osteoarthritis of hip)
• M16.5- (Unilateral post-traumatic osteoarthritis of hip)
• M16.6 (Other bilateral secondary osteoarthritis of hip)
• M16.7 (Other unilateral secondary osteoarthritis of hip)
• M16.9 (Osteoarthritis of hip, unspecified)

Knee

• M17.0 (Bilateral primary osteoarthritis of knee)
• M17.1- (Unilateral primary osteoarthritis of knee)
• M17.2 (Bilateral post-traumatic osteoarthritis of knee)
• M17.3- (Unilateral post-traumatic osteoarthritis of knee)
• M17.4 (Other bilateral secondary osteoarthritis of knee)
• M17.5 (Other unilateral secondary osteoarthritis of knee)
• M17.9 (Osteoarthritis of knee, unspecified)

5th character alert: Remember that not all hip and knee OA ICD-10 codes are four characters; several of the codes go into a 5th character, so be sure you code to the 5th character when ICD-10 instructs.

Follow These Steps to Complete OA Dx

Osteoarthritis codes run from M15.- (Polyosteoarthritis) to M19.93 (Secondary osteoarthritis, unspecified site) in the ICD-10 book. Here’s instruction on how to arrive at the best OA ICD-10 code for each patient.

Step 1: Identify the location of the OA. This could be hip, knee, ankle, elbow, etc.

Example: Notes indicate the patient suffered knee OA.

Step 2: Identify the type of OA. This could be polyosteoarthritis, primary, secondary, posttraumatic, dysplastic, or other.

Example: Notes indicate the patient suffered posttraumatic knee OA.

Step 3: Identify the laterality of the OA. This could be left, right, or bilateral.

Example: Notes indicate the patient suffered posttraumatic right knee OA.

Step 4: Choose an OA code. For the example above, you’d report M17.31 (Unilateral post-traumatic osteoarthritis, right knee) for the patient.

Remember Extra Step for Secondary OA

If you find you’ve got a patient with secondary OA, you’ll need to add another step to the above instructions to completely code the patient.

Reporting primary condition: You’ll need to find out what primary condition the patient suffers from in order to code secondary OA patients completely.

Example: Encounter notes indicate that the patient has secondary left knee OA due to severe obesity caused by excess calories. For this patient, you’ll need to report both M17.5 (Other unilateral secondary osteoarthritis of knee) and E66.01 (Morbid (severe) obesity due to excess calories).