Overcoming Problems Coding Multiple Knee Ligament Repairs

“Multiple ligament repairs can be a real challenge for a coder unless he or she has a thorough understanding of arthroscopic families and the proper use of modifier -51 (multiple procedures) to indicate that more than one procedure was done at one session.

Knee ligament injuries are not unusual. For example, on Jan. 1, the University of Texas (Austin) Longhorns not only lost the Cotton Bowl to the University of Arkansas, they also lost their star quarterback, Major Applewhite, to a torn anterior cruciate ligament (ACL).

Repair of the ACL and rehabilitation will keep Applewhite off the field (and out of spring practice) for six months. Knee ligaments (see box on page 3), particularly the ACL, are vulnerable to injuries caused by excessive twisting (rotation). At the same time, the meniscus cartilage between the femur and the tibia is prone to being squished and dislodged by trauma.

Applewhite’s high-visibility misfortune is actually a common one among athletes on the field and on the slopes. About 15 percent of people who damage an ACL also damage another ligament or the meniscus.

Note: For a discussion of coding for ACL repair alone, see page 84 of the November 1999 Orthopedic Coding Alert.

Multiple Ligament RepairsSimple Cases

Coding for arthroscopic ACL or posterior cruciate ligament (PCL) repair/augmentation or reconstruction is relatively easy, thanks to the contingencies built into the respective codes, explains a physician familiar with multiple procedures. The physician uses 29888 (arthroscopically aided anterior cruciate ligament repair/augmentation or reconstruction) for ACL and 29889 (arthroscopically aided posterior cruciate ligament repair/augmentation or reconstruction) for PCL.

When ACL and PCL repair/augmentation or reconstruction are done during the same operating room (OR) session, a -51 modifier would be attached to the higher paying or higher fee procedure (Medicare Part B guidelines), and it would be listed first. Some coders would also use a -59 modifier (distinct procedural service) on the second procedure to indicate that the procedure was separate from other services.

Note: See page 90 of the December 1999 Orthopedic Coding Alert for a discussion of the advantages and limitations of using modifiers -51 and -59 together.

Open procedures for cruciate ligaments are covered by 27405 to 27409 (repairs) and by 27427 to 27429 (ligamentous reconstruction/augmentation). It is legitimate to code for primary repair of ligament(s) performed in addition to reconstruction if arthrotomy is used for the approach.

For example, for primary ACL repair and reconstruction of a PCL, the correct coding is to report 27407 (repair, primary, torn ligament and /or capsule knee, cruciate) and 27428 (ligamentous reconstruction, augmentation, knee, intra-curricular). Arthroscopic codes 29888 and 29889 cannot be reported when 27427 to 27429 are reported. This goes back to a basic rule which has been in place since 1997, explains Susan Callaway-Stradley, CPC, CCS-P, a coding consultant and educator based in North Augusta, S.C. If you are already doing an open procedure, you cannot bill for an arthroscopic one. There are many reasons a scope might be used during an open procedure, to help visualize, for example. But it cant be billed. Callaway-Stradley adds that if the procedure starts as arthroscopic and must be changed to open, the practice would bill for the higher-paying arthrotomy.

Note: The ICD codes that correspond to meniscal tears in the knee are listed under Tear. Ligament tears are listed under Sprain, Strain (knee) (ligament). A tear of the ACL, for example, gets the diagnostic code 717.83 (old disruption of anterior cruciate ligament).

Multiple Ligament RepairsTougher Cases

Actually, the cases are not as tough as they are frustrating. If an ACL and PCL are repaired using an arthroscopic procedure at the same time as a medial collateral ligament (MCL) or lateral collateral ligament (LCL) repair or reconstruction, the payment for the MCL and LCL will most likely be included with the other procedures.

Neither MCL nor LCL has its own code, and if either were done alone, the choice would be 29909 (unlisted procedure, arthroscopy) with good documentation about what was done and why (an excellent operative report). Then, why not also list the 29909 code in addition to the 29888 or 29889 (or both) when ACL, PCL and LCL repair are tackled during the same arthroscopic procedure? The use of 29909 with listed procedures, even with a -51 modifier, might raise the ire of some carriers, especially Medicare. As far as Medicare is concerned, you only inserted the scope once, explains Callaway-Stradley. Once you get the scope in, as far as the carrier is concerned, the biggest part of the procedure is done.

Basically, it’s going to be a carrier-by-carrier call for multiple ligament repairs says Callaway-Stradley. It’s why a coder must call the carrier, she says. Ask, Do you want us to use a -51 modifier?’ Most private carriers will want it.

What sort of payment can be expected for a combination of procedures? It’s all over the place, says a physician.

What About the Meniscus?

Removal of the damaged meniscus was once a standard treatment. Code 29880 (arthroscopy, knee, surgical; with meniscectomy, medial AND lateral including any meniscal shaving) or 29881 (arthroscopy, knee, surgical; with meniscectomy, medial OR lateral, including any meniscal shaving) apply to arthroscopic procedures.

As the function of the meniscus has become better understood, interest in removing it has waned. The meniscus serves as a dispersion point for forces, much like an air bag between a person and a steering wheel on impact.

Arthroscopic meniscus repair as a separate procedure is reported either with 29882 (arthroscopy, knee, surgical; with meniscus repair, medial OR lateral) or 29883 (arthroscopy, knee, surgical; with meniscus repair, medial AND lateral). Open repair (arthrotomy) is reported with 27403 (arthrotomy with meniscus repair, knee).

Coding Cautions

Modifier -51, even when it is used appropriately, reduces payment for successive procedures that can be coded separately, such as ACL repair and PCL repair. The first procedure is paid at 100 percent, but the second is paid at 50 percent and the third through fifth highest-valued procedures are paid at only 25 percent each.

As bad as the reduction is, a coder can make it worse without intending to do so, cautions Callaway-Stradley. She explains that since Medicare computers scan reimbursement forms, attaching the -51 modifier to each successive procedure will trigger a halving and halving again scenarioor truly diminishing returns.

Callaway-Stradley reminds coders that the -51 modifier cannot be used at all for Medicare for procedures in the same family, such as the one covered by the range 29871 to 29887. According to the National Physician Fee Schedule Relative Value File, when an endoscopic [arthroscopic] procedure is reported with only its base procedurepayment for the base procedure is included in the payment for the other endoscopy.

If a procedure in the 29871 family is done on the same day as a procedure not in the family, both procedures can be billed using the -51 modifier. Thus, for repair of the lateral meniscus (29882) and ACL repair (29888), report both procedures and add a -51 modifier.

Some commercial carriers put age limits on payment for ACL and other ligament repairs. Their rationale is that older patients are less likely to recover full mobility. But research demonstrates otherwise. Physical condition is a better predictor of successful outcome than age, and age limits can probably be successfully appealed.

Finally, arthroscopic procedures to repair the meniscus and the ligaments are robust bundles. Everything integral to the repair (e.g., trimming, shaving or debridement of meniscus; graft harvesting, removal of debris, repair of donor site, partial synovectomy in conjunction with ligaments) is included in the respective procedure. Do not assign additional codes (unbundle).

Coding Challenges Here to Stay

If it seems as though ACL tears are becoming more frequent, they are. During the last 15 years, injuries to knee ligaments have gone up 172 percent. In the same period ankle sprains are down 86 percent. Statistics are from The Stone Clinic web site, www.stoneclinic.com/kjoin.htm, the namesake of Kevin Stone, MD.

Stone practices orthopedic surgery and sports medicine. He attributes the shift in dominant injuries to stiffer [ski] boots and improved bindings, which reduced rotational injuries in the lower leg and ankle and increased them in the knee.

Knee Ligaments and Meniscus” 101

Four ligaments of the kneeall of which tie the femur to the tibiaare most likely to be injured when the knee is subject to unusual rotation. (Other ligaments some of which link to the patella knee cap and fibula are more often damaged in compression traumas and are not considered here.)

The anterior cruciate ligament (ACL) and the posterior cruciate ligament (PCL) crisscross each other linking the condyles of the femur and tibia. The medial collateral ligament (MCL) spans the space between the epiphysis of the tibia and the epiphysis of the femur on the medial (inside) margin of the knee. A lateral collateral ligament (LCL) plays the same role as the MCL but on the lateral (outside) margin of the knee.

In terms of frequency of repairs the ACL ranks first and PCL a distant second. Most orthopedic surgeons favor a brace (conservative treatment) to encourage self-mending of a damaged MCL. Surgical repair of the LCL although not common takes place more frequently than MCL repair.

Surgical (open or arthroscopic) repairs of MCL and LCL are often avoided because surgeries on the ligaments (open in particular) contribute to osteoarthritis and arthrofibrosis. (The theory behind the cause and effect is that the peripheral location of the MCL and LCL means the ligaments experience more trauma in surgery.)

A cushion of fibrocartilagethe meniscusseparates the space where the femur and tibia articulate. The meniscus is divided into a medial portion and a lateral portion. Both parts are as vulnerable to rotational injuries as are the four ligaments mentioned already. “