Neurology & Pain Management Coding Alert

Hint: It's not always the 337.2x series

Without proper ICD-9 coding, you cannot justify the multiple tests often required to confirm a reflex sympathetic dystrophy (RSD) diagnosis. If your neurologist suspects that a patient has RSD, you should report signs and symptoms until testing reveals a definitive diagnosis.

The following expert tips can help your practice collect for RSD treatment every time.

The most important RSD rule is that you should not code an RSD diagnosis (337.20-337.22, 337.29) until testing reveals a definitive diagnosis, says Trish Bukauskas-Vollmer, CPC, owner of TB Consulting in Myrtle Beach, S.C. "Stick with signs and symptoms until you are certain of the RSD diagnosis," she continues. Neurologists may find RSD particularly difficult to diagnose because the symptoms may not be present from one hour to the next. The physician must take a careful and detailed history of the possible signs.

Start with an E/M visit: The E/M visit (99201-99205 for new patients, 99211-99215 for established patients) is the first step to diagnosis. The following outlines the most common diagnoses that neurology practices see during the three RSD stages:

Stage-one symptoms: The patient has prolonged pain, sensitivity to temperature (like the cool air from an opened refrigerator) (782.0, Disturbance; temperature sense), sensitivity to light touch (782.0, Disturbance; touch), severe (usually a burning-type) pain, skin color changes (generally a loss of color so the skin appears almost white), swelling and redness (common in cases that are vascular in origin).

Stage-two symptoms: The affected area becomes blue, cold and painful. Osteoporosis (733.0x) and joint stiffness (719.5x) can develop at this stage.

Stage-three symptoms: Muscles and tendons waste away, including contracture and withering of the affected limb. For muscle wasting, report diagnoses such as 728.2 (Muscular wasting and disuse atrophy, not elsewhere classified).

If the patient has severe pain, the neurologist may administer a nerve block on the same day as the E/M visit to alleviate the patient's pain until he can establish a definitive diagnosis and begin treatment.

You should report the appropriate E/M code (in this case, 99203) with modifier -25 (Significant, separately identifiable evaluation and management service by the same physician on the same day of the procedure or other service) appended, followed by the nerve block code (64400-64484).

The -25 modifier on 99203 tells the payer that the E/M service goes above and beyond any E/M component included in the nerve block. Without modifier -25, the payer won't reimburse for the E/M and procedure separately, warns Kimberly Hodges, CPC, an office manager for a two-physician practice in Titusville, Fla.

If another physician refers a patient to you and asks you to take over the patient's RSD care, you cannot report a consult, because this is considered a transfer of care, says Mary Falbo, MBA, CPC, president of Millennium Healthcare Consulting Inc., a national healthcare consulting firm in Lansdale, Pa. If, however, the physician sends the patient to you, asks you to run tests and report back to him, you can probably report a consult (99241-99245).

Example: A primary-care physician refers a patient whose test results indicate RSD. The neurologist performs a new patient E/M visit (99203) as well as a nerve block (64400-64484). This would not be a consult because the patient has already been diagnosed and the referring physician wants you to treat the patient for this condition.

Diagnostic tests for RSD can be broken into two types: anatomical and physiological tests.

Anatomical tests, such as myelograms, MRIs, CAT scans and x-rays, are unreliable for pain disorders because they do not quantify pain; therefore, physicians usually prefer physiological tests, which measure the interactions within the patient's body.

The most common physiological tests for diagnosing RSD include thermogram (infrared imaging), the acetone drop test, and a tri-phase bone scan.

Thermography (93740, 93760 and 93762) measures the temperature on and beneath the skin. The acetone drop test (82010, Acetone or other ketone bodies, serum; quantitative) demonstrates allodynia or pain from light touch. An RSD patient will experience cold hyperalgesia (782.0, Disturbance of skin sensation).

A tri-phase bone scan (78315, Bone and/or joint imaging; three-phase study) is a special type of bone scan that shows increased uptake of blood in the injured limb compared to the healthy limb. This test can assess the stage of RSD and rule out other problems like neoplasms or osteomyelitis.

After the neurologist definitively diagnoses RSD, you will code 337.20 (Unspecified RSD), 337.21 (RSD of the upper limb), 337.22 (RSD of the lower limb), or 337.29 (RSD of other specified site). The usual RSD causes, such as injury or trauma, may warrant an E or V code as a secondary diagnosis.

For example: If a patient has RSD due to trauma from falling off a ladder, list the RSD diagnosis (337.20-337.29) and then the appropriate E code to describe the ladder fall (E881.0). "As coders, you tell a story," says Anita Carter, LPN, CPC, of A+ Medical Management & Education. "If a patient has RSD due to trauma, then by all means, include it." And if RSD follows a fracture, trauma or other injury, you can code appropriate "late effects" code (905.x, Late effects of musculoskeletal and connective tissue injuries).

After the neurologist has brought the RSD under control, he must also treat the original underlying problem or coexisting condition. Coexisting conditions may include nerve entrapment (355.9, Mononeuritis of unspecified site), peripheral neuropathies (356.9, Hereditary and idiopathic peripheral neuropathy; unspecified), carpal tunnel syndrome (354.0), tarsal tunnel syndrome (355.5), and thoracic outlet syndrome (353.0).

Tip: When you code the underlying problem, you should always list the diagnosis that the neurologist is actually treating as the principal diagnosis, Carter says.

Example: An RSD patient returns after two years of treatment and is doing well. The physician treats carpal tunnel syndrome, the underlying problem. Carpal tunnel syndrome (354.0) should be the first diagnosis code. You should report RSD only as a secondary diagnosis.