ISASS and Coding Community Lend Support for Lateral MIS Procedures

In the December 2020 issue of International Journal of Spine Surgery (www.ijssurgery.com), two important articles focus on MIS SI joint fusion with associated recommendations and evidence-based guidelines for payor criteria and physician coding from the International Society for the Advancement of Spine Surgery (ISASS):

• Editorial on SI joint fusion procedures and associated CPT coding
  
• Update to the ISASS Policy Statement on MIS Sacroiliac Joint Fusion

The publications reviewed all available literature and evidence for current SI joint fusion procedure types, as well as reviewed existing CPT coding used to describe them. The articles confirm that the available evidence for lateral transiliac MIS SI joint fusion (i.e., iFuse) is sufficient to determine medical necessity and ISASS recommendations for adoption and coverage; but that evidence for posterior (dorsal) MIS SI joint fusion (whether using bone allograft products or 510k-cleared medical devices) is lacking, and not recommended at this time.

ISASS’ findings confirm what many coding experts have already identified as the appropriate CPT codes to report various types of MIS SI joint fusion. Most recently, coders point out in the October issue of AAPC Healthcare Business Monthly that while 27279 describes laterally placed implants such as iFuse, and has appropriate Work RVUs, the MIS posterior (dorsal) SI joint fusion procedure should be reported using an Unlisted CPT code (22899 [unlisted procedure, spine] or 27299 [unlisted procedure, pelvis or hip joint]), since neither 27279 nor 27280 CPT codes describe them.