Neurology & Pain Management Coding Alert

Hint: Start by distinguishing from F-wave studies.

You might turn to Appendix J of the CPT® manual most often to review the maximum number of nerve conduction studies you typically report for specific indications. Don't overlook the next column that addresses H-reflex (or Hoffmann's reflex) studies, however, because these tests have specific considerations to keep in mind while avoiding denials.

1. Learn Difference Between Tests

H-reflex and F-wave studies both test the patient's late response reflex and evaluate the entire length of a nerve, but in different ways. F-waves assess motor nerve fiber function along a nerve and are generally performed in conjunction with conventional motor nerve conduction studies. H-reflex studies, however, involve both the sensory and motor nerve fibers and test both connections in the spinal cord.

"Both late response tests can be valuable in evaluating nerve conduction in the more proximal portions of the nerve, meaning you're studying conduction closer to the spine," explains Marvel Hammer, RN, CPC, CCS-P, PCS, ACS-PM, CHCO, owner of MJH Consulting in Denver. "These nerve areas are often inaccessible to direct nerve conduction assessment using conventional techniques."

Tip: Your physician's report should identify the nerves evaluated with the site of nerve stimulation and muscle recording, and the test characteristics, including latency. Watching notations of the tested nerves in your neurologist's documentation will help you determine when to code for an H-reflex study instead of an F-wave study.

2. Verify Muscle Tested to Determine Code

Once you've determined that you're coding for an H-reflex study, CPT® includes two self-explanatory codes for the procedure:

• 95934 -- H-reflex, amplitude and latency study; record gastrocnemius/soleus muscle
• 95936 -- ... record muscle other than gastrocnemius/soleus muscle.

Knowing the muscle your neurologist tests is the key to selecting the correct code.

"H-reflex studies usually involve assessment of the gastrocnemius/soleus muscle complex in the calf," says Anne M. Dunne, RN-BC, MBA, MSCN, director of healthcare consulting with Grassi and Company in Jericho, N.Y. "In rare instances, H-reflexes need to be tested in muscles other than the gastrocnemius/soleus muscle, such as in the upper limbs or the intrinsic small muscles of the hand and foot."

Result: Most of your reporting for H-reflex studies will include 95934 because physicians test the gastrocnemius/soleus muscle complex more often than other areas. Verify documentation, however, before automatically assigning 95934 for every H-reflex study.

3. Confirm an Appropriate Diagnoses

"H-reflex studies are very common for the lower extremities, especially when the patient experiences radicular pain," Hammer says. "The late response studies are often used in the evaluation of radiculopathies, plexopathies, polyneuropathies and proximal mononeuropathies. In some cases, these studies may be the only abnormal diagnostic test."

Some payers, including some Medicare LCD coverage policies --" have limited indications for H-reflex studies. Most payers allow 723.4 (Brachial neuritis or radiculitis, NOS), 724.3 (Sciatica) or 724.4 (Thoracic or lumbosacral neuritis or radiculitis unspecified) for radiculopathy, and some allow 729.5 (Pain in limb), 781.2 (Abnormality of gait) or 781.3 (Lack of coordination). Always code based on your provider's documentation, but be aware of diagnoses the payer requires to support medical necessity of the diagnostic testing.

4. Watch for Modifier Opportunities

The codes for H-reflex studies assume unilateral procedures, but don't stop with a single code.

"Even if the patient has unilateral pathology, the physician almost always tests both extremities," Hammer says. The Medicare Physician Fee Schedule (MPFS) assigns codes 95934 and 95936 the bilateral status indicator of '1,' so you can report bilateral tests when appropriate."

"H-reflex studies are usually performed bilaterally because symmetry of responses is an important criterion for abnormality," Dunne explains. "Bilateral studies are indicated when an abnormal response is found in a unilaterally symptomatic limb or when there is a question that the response could be abnormal for reasons other than pathology, such as advanced age."

Option 1: If you're billing bilateral H-reflex studies to Medicare, report one unit of service as a single line item. Append modifier 50 (Bilateral procedure) to indicate the bilateral nature.

Option 2: When reporting bilateral H-reflex studies to a non-Medicare payer, check guidelines for reporting bilateral services before submitting your claim. Some might want a single line item with modifier 50, but others might require two line items with modifiers RT (Right side) and LT (Left side).

"Being able to bill bilaterally is one of the big differences between H-reflex studies and the other tests found in Appendix J," Hammer says. "You cannot bill the other tests bilaterally, per the MPFS. You don't want to miss the opportunity when you have it with H-reflex studies."