Orthopedic Coding Alert

Treatment location and diagnoses clue you in to correct code sets.

If knee arthroscopy hovers near the top of your surgeon's case list, don't get lost when he accesses multiple compartments. Learn your anatomy and follow some simple coding rules " including how to deal with knee areas that aren't associated with particular compartments " to stay on track every time.

Tip 1: Translate the Knee Compartment Location Into Correct Codes

CPT includes a large list of codes for knee procedures, but everything your surgeon does within the knee must take place within one (or more) of three compartments. Your first step in successful coding is knowing each compartment's location:

Medial: The inner joint surfaces of the femur and tibia

Lateral: The outer joint surfaces of the femur and tibia

Patellofemoral: The joint between the underside of the kneecap (patella) and the femur. The surgeon must document which compartment (or compartments) he accesses during the procedure. You can code separately for each procedure performed in a separate compartment, so having clear documentation helps your bottom line as well as your claim's accuracy.

Example: The orthopedist's notes state that he completed medial meniscal repair and removed a 4 mm loose body from the lateral compartment. His clear documentation makes it easy for you to confidently report both 29882 (Arthroscopy, knee, surgical; with meniscus repair [medial or lateral]) and 29874 (... for removal of loose body or foreign body [e.g., osteochondritis dissecans fragmentation, chondral fragmentation]).

Tip: When coding for multiple compartments, report the correct modifier or code to designate the separate status. For commercial payers, append modifier 59 (Distinct procedural service) to the second procedure code  when necessary, says Randa Cain, coding and charge capture supervisor in the Central Business Office of Martha Jefferson Hospital in Charlottesville, Va. For Medicare, report G0289 (Arthroscopy, knee, surgical, for removal of loose body, foreign body, debridement/shaving of articular cartilage [chondroplasty] at the time of other surgical knee arthroscopy in a different compartment of the same knee). HCPCS designates G0289  as "carrier discretion," so verify coverage with your local carrier before filing the claim.

Caution: Do not confuse portals with compartments, warns Kristine Newton, CPC, billing coordinator for Sarasota Orthopedic Associates in Florida. A portal is the surgeon's access point to the knee, but doesn't always equal the number of compartments you should report.

Example: Some surgeons can use two portals to access the three compartments when others use five portals " it depends on the surgeon's preference and/or the patient's anatomy once surgery begins. "This might confuse someone working an appeal where an insurance company says there is bundling " it is a way to trip up the inexperienced appeal staff by the denial and might inadvertently get written off," Newton says.

Tip 2: Take Note of These Common Knee Arthroscopic Terms

Even if your orthopedist doesn't do the best job specifying individual compartments,his notes regarding the procedures themselves should point you in the right direction. Many of the knee's anatomic structures (such as the meniscus, femoral condyle, collateral ligament, and more) can apply to either side of the knee so include "medial" or "lateral" in the name for clarification. Similarly, procedures involving the patella should be easy to spot. That narrows your options, but watch for some other terms that often get tricky.

Intra-articular notch: This is the open posterior area of femur between the medial and lateral femoral condyles. Although your surgeon might mention the intra-articular notch by name, CPT does not consider the area a compartment for coding purposes. "My doctor explained that this is what doctors consider a fourth compartment, which is space behind the femoral condyles," Cain says. "I haven't actually had him do a procedure there but he did mention in a note that he scoped it. I didn't charge anything in addition to the scope for the other compartment he did."

Plica: Patients with plica syndrome (727.83) experience pain and/or snapping in the knee because of inflammation of a band of tissue. Plica syndrome is most often found in the patellofemoral compartment, but can occur in any of the three compartments. Verify the details before assuming its location.

Anterior cruciate ligament (ACL) debridement: The ACL lies in the middle of the knee to prevent the tibia from sliding in front of the femur and to provide rotational stability to the knee. Coders sometimes wonder which compartment to associate the ACL with from a reporting standpoint, but the question might be moot. "Everything I've read said you should use 29999 (Unlisted procedure, arthroscopy) for ACL debridement unless the surgeon also does a repair," Cain says. Use 29875 (Arthroscopy, knee, surgical; synovectomy, limited [e.g., plica or shelf resection] [separate procedure]) as a comparison code for setting the relative value units (RVUs) you report for 29999 in this procedure. Code 29875 carries 12.82 total RVUs for facility or non-facility work.

If the surgeon completes a repair along with the ACL debridement, you'll only report the repair. Submit 29888 (Arthroscopically aided anterior cruciate ligament repair/augmentation or reconstruction), which carries 25.99 total RVUs for facility or non-facility work and includes debridement.

Tip 3: Catch the Descriptor Details

Many knee arthroscopy descriptors vary by only a word or two. Don't overlook details such as "limited" and "major" to distinguish the procedure's extent or "medial or lateral" versus "medial and lateral" to describe the procedure site.

Another tip: "Some coders don't realize that microfracture is aprocedure and that there is a code for it," Cain says. "They think it's a diagnosis instead of a procedure." When your surgeon documents microfracture, turn to CPT instead of ICD-9. Code 29879 (Arthroscopy, knee, surgical; abrasion arthroplasty [includes chondroplasty where necessary] or multiple drilling or microfracture) is the coding answer you need.