Committee Response to CPT Code

CPT code 20936 reads "Autograft for spine surgery only [includes harvesting the graft]; local [eg. ribs, spinous process, or laminar fragments] obtained from the same incision". The SRS agrees that local bone harvested from the spinal incision and within the area already being dissected to prepare for fusion is incidental to the posterior fusion codes CPT 22800-22804. This would include bone fragments from the posterior elements of the spine: laminar fragments, spinous processes and facets and perhaps rib heads or small fragments of the ribs obtained from the spinal dissection as it extends to the tip of the transverse processes. Surgeons would all agree that harvesting of ribs is an entirely different and independent procedure that falls under the code of 20937, " Autograft for spine surgery only: morselized through separate skin or fascial incision". Although the major spine incision may be used, another fascial incision is required and surgeons often use another parallel longitudinal incision centered over the rib hump. Even if the rib harvesting is through the main spinal incision, it requires a separate fascial incision, considerable dissection out laterally over the ribs, and a lengthy procedure to subperiosteally expose multiple ribs and remove them from the chest. It requires significant time and expertise, but certainly may be the surgeon's choice for the appropriate source of autologous graft material in order to obtain adequate amounts of autograft, to correct the rib hump deformity, and to allow further correction of the spinal deformity. (HH Steel, "Rib Resecton and Spine Fusion in Correction of Convex Deformity in Scoliosis" JBJS(A), 1983 Sept, 65(7) pp: 920-925. DC Mann, CL Nash Jr., MR Wilham, RH Brown, "Evaluation of the Role of Concave Rib Osteotomies in the Correction of Thoracic Scoliosis", Spine 1989, May, 14(5) pp:491-495.) When rib autograft is being harvested to serve as the primary graft material, that is another situation entirely than using local available bone. As above, harvesting of multiple lengthy segments of ribs includes not only extensive additional dissection and surgical knowledge and skill but also significant time in then preparing the rib segments into strips appropriate for graft material. This is not an incidental procedure to the main posterior arthrodesis codes 22800-22804. It is an additional procedure taking significant time, additional risk, additional blood loss and requires specialized knowledge and skill on the surgeon's part. It is done to obtain autograft by those surgeons who wish to use the patient's own bone and as an alternative to harvesting the iliac crest for autograft. Clearly CPT code 20937 would be the appropriate code in this case, not CPT 20936.