Orthopedic Coding Alert

Surgeons have performed hip core decompression to alleviate patients' pain for years, yet CPT still does not include a code for it. Avoid the self-inflicted pain of denials by examining your coding options and knowing what to expect based on the disease status.

According to CPT and the American Academy of Orthopedic Surgeons (AAOS), you should report hip core decompression with 27299 (Unlisted procedure, pelvis or hip joint). HCPCS does include S2325 (Hip core decompression), but it's non-covered by Medicare. "I bill 27299 for every insurance except Medicare and Florida Blue Cross/Blue Shield," says Conni Morris, a coder with Kennedy-White Orthopaedic Center in Sarasota, Fla.

Tip: When filing with 27299, Morris compares it to 27071 (Partial excision [craterization, saucerization] [e.g., osteomyelitis or bone abscess]; deep [subfascial or intramuscular]). She includes an article from an AAOS bulletin as backup and reports no problems.

Know guidelines: Payer policies can change, so be sure you're up-to-date with correct reporting. For example, Morris says Blue Cross/Blue Shield of Florida stopped accepting 27299 for hip core decompression and now only accepts S2325.

Be sure to read the fine print of your payer's policy regarding claims and reimbursement for hip decompression, because they could have very specific coverage guidelines. Keep these two tips in mind:

• Double-check the diagnosis. Common diagnoses on payer policies include 733.40 (Aseptic necrosis of bone, site unspecified), 733.41 (Aseptic necrosis of head of humerus), 733.42 (Aseptic necrosis of head and neck of femur), and 733.43 (Aseptic necrosis of medial femoral condyle). Some payers also list diagnoses for other anatomic locations. For example, Aetna's policy includes 733.44 (Aseptic necrosis of talus), 733.45 (Aseptic necrosis of jaw), and 733.49 (Other aseptic necrosis). "I always make sure that we follow our carriers' policies and research them prior to surgery in unlisted procedures such as this," says Catherine Nolin, CPC, surgical and ASC coder with Central Maine Orthopaedics in Auburn.

"What I would look for in cases for the hip is that the patient has documented avascular necrosis, also referred to as osteonecrosis."

• Verify the stage. Even if your carrier covers hip core decompression, they might limit the timeframes. "Aetna has a very detailed policy regarding this surgery and will only cover the hip core decompression for medical necessity for the treatment of early/pre-collapse avascular necrosis of the hip," Nolin says. Other payers including United Healthcare/Oxford subscribe to this mindset, stating that core decompression is not considered a medically necessary treatment of "late" avascular necrosis of the femoral head.

Translation: The disease must be classified as either Stage I or Stage II before the payer will approve coverage. "Stage 1 is when changes can't be seen on X-ray, but can be seen on MRI," explains Bill Mallon, MD, orthopedic surgeon and medical director at Triangle Orthopaedic Associates in Durham, N.C. "Stage 2 does have mild Xray changes but with no collapse or development of osteoarthritis." Several classification scales exist, Mallon says, so assigning the patient's stage of disease depends partly on which scale you follow.

Surgeons sometimes combine hip core decompression with other procedures such as nonvascularized or vascularized bone grafts or electromagnetic treatment in hopes of stimulating formation of new bone tissue. Watch for opportunities to also report:

• 20955 -- Bone graft with microvascular anastomosis; fibula

• 20972 -- Free osteocutaneous flap with microvascular anastomosis; metatarsal

• 27070 -- Partial excision (craterization, saucerization (e.g., osteomyelitis or bone abscess); superfiicial (e.g., wing of ilium, symphysis pubis, or greater trochanter of femur)

• 27071 -- ... deep (subfascial or intramuscular)

• 38241 -- Bone marrow or blood-derived peripheral stem cell transplantation; autologous.

AVN is a progressive condition, so patients might eventually need hip replacement surgery. Surgeons wait several months to see if the patient's AVN has responded to the core decompression before they proceed with a total hip replacement, Nolin says.

"Most people say patients should be non-weight bearing for six months after the core decompression," Mallon says. Trying to evaluate the procedure's success before that point would be too early.

Days count: Because you report the hip decompression with an "unlisted" code, check the global period with your payer before coding additional procedures such as hip replacement.

"Unlisted procedures carry a 'YYY' status, which indicates that CMS does not have an established global period set at the national level," Nolin explains. "Individual carriers determine if the global concepts apply."