Neurosurgery Coding Alert

Question: The doctor uses what he describes as a -fibular allograft bone plug or bone spacer.- I-ve been told I can report the allograft used in a posterior lumbar interbody fusion (PLIF) as 22851 when a -cornerstone allograft- is used, rather than using code 20931 (Allograft for spine surgery only; structural). But the CPT manual states -threaded bone dowel- in the code descriptor for 22851. What should I report?


Washington Subscriber


Answer: You should use 22851 (Application of intervertebral biomechanical device[s] [e.g., synthetic cage(s), threaded bone dowel(s), methylmethacrylate] to vertebral defect or interspace) once for each level at which your neurosurgeon places this type of graft. The code descriptor's examples are just descriptive, and are not a complete listing of the only possible devices your physician can use in order for you to report 22851.

Cornerstone is the brand name for numerous allograft products that come in a variety of shapes and sizes. Physicians use their products in all manner and levels of spinal fusion procedures. Most are specially shaped pieces of fibula, which may be threaded, ridged, beveled or otherwise prepared to promote bony in-growth to aid in a solid fusion.

One type of Cornerstone graft is made up of two pieces of cortical bone surrounding trabecular bone, held together by metal pins and shaped for insertion between two vertebral segments. Cornerstone grafts fall under -biomechanical devices- in the code description of 22851.