AMN Healthcare MedPartners Clarifying Spinal Interbody Fusion Techniques


Many coders struggle with coding spinal fusion procedures.  First, the terminology can be confusing. For example the term “anterior” can refer to two different components of the procedure.  Additionally, new techniques make it difficult to “picture” what is going on when reading an operative note.  Fusion procedures can be performed through the back or posterior, through the front or anterior, or through the side or lateral, and the use of different types of devices can be daunting.


The seventh character, the qualifier for spinal fusion procedures in ICD-10-PCS identifies the surgical approach by a specific body plane, i.e. anterior, posterior, as well as portion of the vertebral column, i.e. anterior, posterior.  One can easily see where confusion can arise.  A coder must first identify where incisions are being made, through the back, the front, or on the side of the patient.  This will reveal the first portion of the PCS qualifier (anterior=front, posterior=back, and lateral=side).  For the final portion of the qualifier to be determined the coder must determine what portion of the vertebral column is being fused.  The foramen, spinous process, facets, and lamina are considered the posterior vertebral column.  The anterior column includes the vertebral disc. 


Not only is the above information a challenge for coders, add in the many different types and techniques using interbody fusion devices and you begin to see why it is important for coders to master all aspects of this challenging surgery.   

Interbody fusion devices are also known as cages because they house bone graft materials and are placed between vertebral bones.  Once the bone graft heals the area is fused together as if it is a single bone.  There are varied techniques on how these cages are placed.  For example, an anterior lumbar interbody fusion (ALIF) involves placing the cage between spine levels through the front of the patient, or anterior approach.  This approach involves moving major vessels away from the surgical site and sometimes can involve a vascular surgeon.   Another example is the direct lateral interbody fusion technique or DLIF.  This involves placing the cage in between the vertebral segments via an incision in the side of the patient.  A transforaminal lumbar interbody fusion (TLIF) involves entering the disc space from one side and leaving a portion of the disc behind to house the cage and bone graft materials. This small incision technique allows for a shorter recovery period and less post-operative pain.  These are just a few of the documentation challenges that the coder will face in coding spinal fusions.

Understanding each component of a procedure and applying the specific PCS guidelines is imperative to proper spinal fusion coding.  Our inpatient coders are provided both clinical and coding education through our LMS (learning management system) to help them understand these nuances and prevent the over-coding or under-coding commonly seen among inexperienced coders.  We have the workforce solutions to assist with all of your HIM coding needs.


Dee Mandley, RHIT, CCS, CCCS-P, CDIP

Content Manager-Inpatient