Spinal Bone Graft Coding, as Easy as 1, 2, 3
If you can master basic terminology and identify within documentation the answer to three key questions, you can accurately apply spinal bone graft codes.
1. Is the Bone Graft from the Patient’s Own Body?
Bone harvested from the patient’s own body is known as an “autograft.” For spinal grafts, the applicable autograft codes are:
+20936 Autograft for spine surgery only (includes harvesting the graft); local (eg, ribs, spinous process, or laminar fragments) obtained from same incision (List separately in addition to code for primary procedure)
+20937 Autograft for spine surgery only (includes harvesting the graft); morselized (through separate skin or fascial incision) (List separately in addition to code for primary procedure)
+20938 Autograft for spine surgery only (includes harvesting the graft); structural, bicortical or tricortical (through separate skin or fascial incision) (List separately in addition to code for primary procedure)
Note that all of the above codes include harvesting of the bone, which is not separately reported, as well as shaping or preparation of the graft, prior to placement.
If the bone for the graft comes from a bone bank or donor other than the patient, it is an allograft. The spinal allograft codes are:
+20930 Allograft, morselized, or placement of osteopromotive material, for spine surgery only (List separately in addition to code for primary procedure)
+20931 Allograft, structural, for spine surgery only (List separately in addition to code for primary procedure)
Like 20936-20938, the allograft codes include shaping or preparation of the graft material.
2. Where’s the Incision?
When coding for spinal autograft only, you must also determine whether the bone for the graft is harvested from the same site into which the graft will be placed, or from a separate site.
When the surgeon harvests and places the bone via the same incision, select the “local” autograft code, 20936. When the bone is harvested from a different incision, or when using allografts, you must answer an additional question.
3. Is the Graft Structural or Morselized?
Morselized bone grafts are small pieces of bone used to pack defects and to promote new bone growth. For a morselized autograft, choose 20937. For a morselized allograft, select 20930.
A structural bone graft is a single piece of bone, which provides direct support for skeletal structures. For a structural autograft, select 20938. For a structural allograft, report 20931.
Threaded bone dowels are an exception: Per CPT® Assistant (February 2005), “Threaded bone dowel is the only bone allograft that would qualify for code 22851 [Application of intervertebral biomechanical device(s) (eg, synthetic cage(s), methylmethacrylate) to vertebral defect or interspace (List separately in addition to code for primary procedure)].”
Bonus Tip: Multiple Grafts and Modifiers
You may report a maximum of one unit of any spinal bone graft code, per session, even if the surgeon places multiple spinal bone grafts. CPT® Assistant (April 2012) instructs, “When more than one type of bone graft is required, the appropriate code(s) from the 20930-20938 series are reported only once per operative session, regardless of the number of vertebral levels being surgically fused (i.e., not once per spinal interspace or segment fused).” For this same reason, you should never append modifier 50 Bilateral procedure to bone graft codes 20930-20938.
Per CPT® instructions, you should not append modifier 62 Two surgeons to bone graft codes 20930-20938. And, because 209930-20938 are add on codes, you would never report them with modifier 51 Multiple procedures appended.