Neurosurgery Coding Alert

Question: Codes 63045-63047 refer to vertebral segments. Does this identify a single vertebra, such as third lumbar (L3) vertebra, or does it refer to the motion segment (where two vertebrae meet), such as L3/4?
Illinois Subscriber Answer: A vertebral segment describes "the basic constituent part into which the spine may be divided," according to CPT definitions. A vertebral segment comprises a single complete vertebral bone with its associated articular processes and laminae.
 
A vertebral interspace, conversely, is the non-bony compartment between two adjacent vertebral bodies, which contains the intervertebral disk and includes the nucleus pulposus, annulus fibrosis and two cartilaginous endplates.
 
Therefore, to report a laminectomy of two lumbar segments (L3 and L4), you should select 63047 (Laminectomy, facetectomy and foraminotomy [unilateral or bilateral with decompression of spinal cord, cauda equina and/or nerve root(s), (e.g., spinal or lateral recess stenosis)], single vertebral segment; lumbar) and +63048 (...each additional segment, cervical, thoracic, or lumbar [list separately in addition to code for primary procedure]). Because 63048 is an add-on code, you do not need to report modifier -51 (Multiple procedures).
 
In contrast, to report a unilateral hemilaminectomy of one lumbar interspace (L3-L4), you should use 63030 (Laminotomy [hemilaminectomy], with decompression of nerve root[s], including partial facetectomy, foraminotomy and/or excision of herniated intervertebral disk; one interspace, lumbar [including open or endoscopically assisted approach]).