Neurology & Pain Management Coding Alert

Question: I reported 64493 for a lumbar pars injection. The associated diagnosis is lumbar pars defect, but that does not meet medical necessity for 64493. Is this the correct CPT® code?  

North Dakota Subscriber

Answer: Your CPT® procedure code is correct, but you might need to take a closer look at your diagnosis coding. 

The pars interarticularis is the segment of vertebral bone between the superior and inferior articular facet. Because of this location, a pars defect injection technique is similar to a facet joint injection. Many providers report the procedure as a facet joint injection, with 64493 (Injection[s], diagnostic or therapeutic agent, paravertebral facet [zygapophyseal] joint [or nerves innervating that joint] with image guidance [fluoroscopy or CT], lumbar or sacral; single level). A Q&A in the February 2011 CPT® Assistant supports this coding. 

Diagnosis choices: A pars defect may be congenital (756.11, Congenital spondylolysis, lumbosacral region) or due to trauma, stress, or sports injuries (738.4, Acquired spondylolisthesis). Private payers might accept both of these diagnoses – along with many others –with 64493. The Medicare local coverage determination (LCD), however, only lists 738.4 as supporting medical necessity for 64493. Verify the patient’s situation so you can choose the most accurate diagnosis code that supports medical necessity.