Is bone marrow aspirate bone grafting (Bone Marrow Aspirate) medically necessary as an adjunct to spinal fusion?

Bone Marrow Aspirate (CPT 20939) is NOT Medically Necessary for Cervical Fusion

Based on the strongest available guideline evidence, bone marrow aspirate (BMA) as an adjunct to spinal fusion should NOT be certified for this cervical fusion procedure because there is insufficient evidence to support its use, and the insurance policy correctly denies coverage based on established clinical practice guidelines.

Guideline-Based Denial Rationale

The Journal of Neurosurgery guidelines provide the definitive recommendation on this matter:

• Grade I evidence states there is insufficient evidence to recommend for or against the use of bone marrow aspirate composite as an autograft substitute for posterolateral fusion 1
• The only Grade C recommendation supporting BMA use is specifically when combined with hydroxyapatite (HA) with local autograft as a substitute for autologous iliac crest bone in instrumented posterolateral fusion—this applies to lumbar fusion, not cervical fusion 1
• The guidelines explicitly note that BMA recommendations are based on single Level V studies with inadequate evidence quality 1

Why This Cervical Case Does Not Meet Criteria

The patient is undergoing C4-6 anterior cervical discectomy and fusion (ACDF), which presents several critical distinctions:

• The approved procedures (22551,22552,22845,22853,20930) already provide adequate bone grafting options without requiring BMA 2
• The insurance policy's CPB 0411 specifically states BMA has "insufficient medical evidence for all other orthopedic applications...as an adjunct to spinal fusion" 2
• Allograft (CPT 20930) is already certified and provides equivalent fusion outcomes with Grade C evidence supporting its use 1

Available Evidence-Based Alternatives Already Approved

The following bone graft options are already certified and have superior evidence:

• Allograft materials (CPT 20930): Grade C evidence supports cadaveric allograft and demineralized bone matrix as medically necessary for spinal fusions, with 100% bone allograft considered appropriate regardless of implant shape 1
• Local autograft from decompression: Bone harvested during the surgical approach provides osteogenic potential without additional procedures 2, 3
• Synthetic cages/spacers (CPT 22853): Already approved for this case with established efficacy in cervical fusion 2

Critical Distinction: Lumbar vs. Cervical Evidence

The limited positive evidence for BMA exists only in the lumbar spine context:

• The Grade C recommendation for HA with local autograft/BMA applies specifically to "instrumented posterolateral fusions"—a lumbar technique 1
• No guideline recommendations exist supporting BMA use in anterior cervical fusion 1, 2
• Research studies showing potential benefit (such as the cervical study achieving 76.2% fusion rates with BMA) are single-center retrospective reviews that do not override guideline-level evidence 4

Why Research Evidence Cannot Override Guidelines Here

While some research suggests potential benefit of BMA in cervical fusion 4, this evidence is insufficient to justify coverage:

• The American Association of Neurological Surgeons explicitly states BMA "is not medically necessary for posterior lumbar decompression with transforaminal lumbar interbody fusion (TLIF) for lumbar radiculopathy, as its effectiveness has not been established" 2
• If BMA lacks sufficient evidence for lumbar TLIF, it certainly lacks evidence for cervical ACDF where even less data exists 2
• The 2018 ISASS guidance notes that CPT 20939 became effective specifically for "spine surgery only" but does not establish medical necessity—only coding capability 5

Clinical Context Supporting Denial

This 51-year-old patient with cervical degenerative disc disease, C5-6 stenosis, and C4-5 grade I spondylolisthesis:

• Has no risk factors requiring enhanced fusion augmentation (not elderly, no documented osteoporosis, no smoking mentioned, no prior failed fusion) 6
• Standard allograft and local autograft provide fusion rates of 89-95% in appropriately selected cervical fusion patients 3, 7
• The addition of BMA would increase costs without established benefit in this population 2, 5

Common Pitfall to Avoid

Do not confuse the existence of a CPT code (20939) with medical necessity—the code exists for billing purposes when BMA is used, but this does not establish that its use is evidence-based or medically necessary 5. The insurance policy correctly applies evidence-based criteria requiring demonstration of efficacy before approving adjunctive procedures 2.

Final Recommendation

Deny CPT 20939 (bone marrow aspirate) as not medically necessary 2. The approved bone graft options (allograft CPT 20930, local autograft, and synthetic interbody devices CPT 22853) provide evidence-based fusion augmentation without the unproven addition of bone marrow aspirate 1, 2, 3.