UnitedHealthcare Spinal Fusion Coverage Update

Coverage Criteria and Evidence Summary

Proven and medically necessary products and indications

The following are considered medically necessary when the listed criteria are met:

Autograft (including Bone Marrow Aspirate): Autografts, including bone marrow aspirate used for bone grafting, are considered proven and medically necessary for enhancement of spinal fusion when clinically indicated.

From policy statement listing proven products

Demineralized Bone Matrix (DBM): Demineralized bone matrix (DBM) without added products listed as unproven is considered proven and medically necessary for enhancement of spinal fusion when used per accepted clinical indications.

From policy statement listing proven products

Allograft-based products that are not specifically listed as unproven or not medically necessary are considered proven and medically necessary for enhancement of spinal fusion when used appropriately.

From policy statement listing proven products

InFUSE Bone Graft (rhBMP-2) — lumbar spine: InFUSE Bone Graft (recombinant human bone morphogenetic protein-2, rhBMP-2) is considered medically necessary for lumbar spine fusion when ALL of the following are met: the approach is anterior or oblique and used with an FDA‑approved interbody fusion device; the patient is skeletally mature (>=18 years or radiographic evidence of epiphyseal closure) with degenerative disc disease; the fusion involves vertebral bodies L2–S1 with spondylolisthesis no greater than grade 1 at the involved level; and the fusion is single‑level.

Specific InFUSE lumbar criteria from policy

InFUSE/MASTERGRAFT Posterolateral Revision Device System: The InFUSE/MASTERGRAFT Posterolateral Revision Device System (or InFUSE BMP used with MASTERGRAFT) is considered medically necessary when used according to FDA indications, in skeletally mature patients (>21 years or radiographic epiphyseal closure) with symptomatic posterolateral lumbar pseudoarthrosis implanted via a posterolateral approach, and when autologous bone and/or bone marrow harvest is not feasible or is not expected to promote fusion.

Specific InFUSE/MASTERGRAFT criteria from policy

Coverage-relevant Evidence Summaries

Evidence-based conclusions relevant to coverage decisions:

Human amniotic tissue: There is limited human evidence that amniotic tissue membrane improves outcomes when used in lumbar spine fusion; long‑term safety and efficacy have not been established.

Suggests investigational stance may be appropriate

rhBMP-2 general findings: Systematic reviews and randomized trials indicate rhBMP-2 often produces more rapid or a higher likelihood of radiographic fusion compared with autograft, but improvements in pain, disability, and long‑term quality of life are inconsistent; short follow‑up and methodological limitations constrain interpretation and long‑term risks cannot be excluded.

Evidence supports increased fusion but variable clinical benefit and safety uncertainties

rhBMP evidence limitations: Many studies of rhBMP-2 have small sample sizes, heterogeneous protocols, short follow‑up, and potential bias, limiting definitive conclusions about clinical benefit and long‑term safety.

Supports need for restricted use and documentation/prior authorization

AANS guideline-based coverage options

Covered as an option when evidence demonstrates comparable fusion rates and clinical outcomes to autograft for the specified procedures:

Posterolateral fusion options (AANS/Kaiser): Use of DBM as a bone graft extender is an option for 1‑ and 2‑level instrumented posterolateral fusions; b‑TCP with local autograft is an option as a substitute for autologous iliac crest bone (AICB) in single‑level instrumented posterolateral fusion; hydroxyapatite (HA) with local autograft/BMA is an option as a substitute for AICB in instrumented posterolateral fusion.

AANS 2014 guideline; Kaiser et al. summaries

Interbody fusion options (AANS/Kaiser): Substitutes for AICB (for example, rhBMP-2 as a substitute or approved synthetic/biologic substitutes) may be considered an option for ALIF with threaded cages and for single‑level PLIF due to similar fusion rates and outcomes; rhBMP-2 can be considered as a bone graft extender for TLIF when used with a structural interbody graft.

AANS 2014 guideline; Kaiser et al. summaries

Unproven or insufficient evidence

Not established / unproven uses:

Expandable interbody fusion systems are considered unproven due to lack of prospective randomized controlled trials with adequate sample size and long‑term follow‑up; current literature is largely retrospective and does not demonstrate clear clinical benefit over static cages.

Refs: systematic reviews and recent retrospective studies

Bioactive glass: There is insufficient high‑quality evidence to determine the efficacy and safety of bioactive glass substitutes compared with ICBG or other established grafts; randomized controlled trials comparing specific bioactive glass products to ICBG are needed.

ECRI assessments and small case series indicate low quality evidence

Covered when clinically indicated per guideline-based recommendations

Coverage stance and recommended uses summarized from guideline and evidence excerpts (NASS; Kaiser et al.):

Interbody fusion — rhBMP-2 uses and limits: rhBMP-2 may be used as a substitute for AICB in ALIF with threaded interbody cages and for single‑level PLIF due to similar fusion rates; it may be considered as a bone graft extender for TLIF when used with a structural interbody graft. There is insufficient evidence to support rhBMP-2 as a supplement for standalone ALIF using femoral ring allograft or with a resorbable spacer in TLIF.

Kaiser et al. 2014; AANS guidance

Posterolateral fusion — rhBMP-2 and alternatives: rhBMP-2 (including when supplemented with HA/b‑TCP matrices) and graft extenders can be options as substitutes for or extenders of AICB in single‑level instrumented posterolateral fusions under specified conditions (e.g., patients >60 for some extenders); evidence is insufficient for routine use in revision posterolateral fusions or certain smoker populations.

Kaiser et al. 2014 summary

NASS recommendations and cautions: NASS indicates rhBMP-2 may be considered for ALIF, PLIF/TLIF, and posterolateral fusions in patients at high risk for nonunion or with inadequate autograft, and for select cervical/thoracic fusions in high‑risk adults; NASS advises against routine anterior/posterior cervical fusion use and against single‑level posterior/posterolateral fusions in healthy adults.

The policy lists several product classes and indications as unproven and not medically necessary due to insufficient evidence of efficacy and/or safety. Specifically included are: cell-based allograft products (for example, mesenchymal stem cell–containing products), human amniotic tissue materials, and certain processed allogeneic products noted in clinical assessments. The policy also identifies ceramic-based products (e.g., beta tricalcium phosphate, calcium phosphate, calcium sulfate) and bioactive glass used alone or combined with other grafts as unproven when evidence is inadequate, and it lists expandable interbody fusion systems and rhBMP-2/InFUSE for indications not specifically covered as not medically necessary for spinal fusion enhancement.

The evidence base for many of these products is limited to small cohort studies, retrospective case series, or manufacturer‑sponsored reports with high risk of bias and short follow-up. Systematic reviews and clinical evidence assessments conclude that large, prospective, randomized trials with patient‑centered outcomes are needed before these products can be considered proven alternatives to autograft for routine use.

Human amniotic tissue products for lumbar spine fusion have limited evidence in human models and long‑term safety and efficacy have not been established. Because of this uncertain benefit and the absence of high‑quality comparative trials, the policy treats human amniotic tissue for lumbar fusion as investigational/unproven and potentially not medically necessary when requested as a routine graft substitute.

Requests relying on amniotic tissue to replace established grafting methods should include strong clinical justification and supporting evidence; absent that, claims may be denied under the policy's unproven product exclusions.

Expandable interbody fusion systems are labeled unproven in this policy. Current evidence is dominated by retrospective series and small observational studies rather than prospective randomized controlled trials with adequate sample size and long‑term follow‑up. Systematic reviews to date report radiographic improvements in some parameters but have not demonstrated a clear clinical benefit over static cages.

Because high‑quality comparative data are lacking, coverage for expandable cages claimed to be superior to static cages may be denied or require prior authorization with a detailed rationale and supporting literature.

The policy follows guideline and evidence summaries that rhBMP-2 (e.g., InFUSE) should not be used for routine anterior and posterior cervical fusion procedures and is not recommended for single‑level posterior/posterolateral fusions in healthy adults. These limitations reflect safety concerns and guideline guidance advising against routine cervical use and against routine use in otherwise healthy single‑level posterior/posterolateral fusions.

When rhBMP-2 is considered, the policy emphasizes use consistent with approved indications, device labeling, and guideline recommendations; off‑label cervical or other unsupported uses should be justified and may be denied when presented without sufficient supporting evidence.

Across product classes the policy highlights pervasive evidence limitations: many cell‑based products, amniotic derivatives, and several allogeneic cell‑preserving products have only low‑quality, biased, or noncomparative data. Clinical evidence assessments repeatedly note small sample sizes, retrospective designs, manufacturer sponsorship, inconsistent outcome reporting, and inadequate follow‑up, which together prevent firm conclusions about comparative effectiveness or safety.

As a result, these products are generally considered investigational or not medically necessary in the absence of robust, high‑quality randomized trials demonstrating clinically meaningful benefit over autograft or established alternatives.

Off‑label uses of rhBMP‑2 have been associated with documented serious complications. Reported safety concerns include postoperative inflammation and related adverse effects, ectopic or heterotopic bone formation, osteoclast‑mediated bone resorption, and inappropriate adipogenesis; life‑threatening complications have been reported with cervical spine use, prompting an FDA public health notification for certain off‑label cervical applications.

Because these adverse events are more frequently described in off‑label settings or with dosing/technique deviations, the policy advises restricting rhBMP‑2 to indications and approaches supported by evidence and labeling, and treating other uses with caution or as not medically necessary without strong justification.

Evidence does not currently demonstrate that expandable interbody cages provide a clear clinical benefit over static cages. Meta‑analyses and systematic reviews report improvements in some radiographic parameters (e.g., anterior disc height, segmental lordosis) but no consistent differences in pain, disability (ODI), subsidence rates, or other key clinical outcomes.

Given the predominance of retrospective data and heterogeneity in device design and surgical technique, the policy finds the evidence insufficient to support routine coverage for expandable cages as superior to conventional static cages.

There is insufficient evidence to support the use of rhBMP‑2 as a supplement in standalone ALIF using femoral ring allograft or when used with a resorbable spacer in TLIF. Guideline summaries (Kaiser et al., 2014) and evidence reviews indicate rhBMP‑2 may be an option in certain interbody and posterolateral settings, but specifically note inadequate data to recommend rhBMP‑2 in these standalone or supplement scenarios.

Because trial data and guideline statements do not establish safety or improved clinical outcomes for these particular applications, such uses are treated as unsupported without additional high‑quality evidence.

Applicable Codes and Regulatory Notices

Applicable codes (reference list)CPT

0814T	Percutaneous injection of calcium-based biodegradable osteoconductive material, proximal femur, including imaging guidance, unilateral.
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).
20939	Bone marrow aspiration for bone grafting, spine surgery only, through separate skin or fascial incision (List separately in addition to code for primary procedure).
22899	Unlisted procedure, spine

FDA device clearance/approval noticesmixed

510(k)	FDA 510(k) premarket notification approvals referenced for multiple products (e.g., Bicera, InFUSE supplements, OptiMesh, Duo).
PMA/HDE	PMA and HDE approvals referenced for devices (e.g., InFUSE PMA supplements; InFUSE/MASTERGRAFT HDE).

Provider Requirements, Prior Authorization, and Documentation

Prior Authorization

Prior Authorization and Applicable Codes

Prior authorization may be required for certain spinal fusion products and procedures. Verify benefit coverage prior to surgery and submit applicable codes and clinical documentation to support medical necessity.

Prior authorization may be needed to demonstrate coverage criteria for covered products (e.g., InFUSE lumbar criteria, autograft, DBM).
Listing of a code in this policy does not imply coverage or guarantee payment; check federal, state, and contractual requirements.

Prior Authorization

Prior Authorization Considerations for rhBMP-2

Requests for rhBMP-2 (InFUSE®) should be reviewed under specific prior authorization considerations because safety concerns, dosing/indication limits, and inconsistent long-term clinical benefit have been reported.

InFUSE (rhBMP-2) is covered for lumbar fusion only when all policy clinical criteria are met (anterior/oblique approach with FDA-approved interbody device; skeletally mature; single-level L2–S1; spondylolisthesis ≤ grade 1).
Off-label uses and indications not meeting policy criteria are considered unproven/not medically necessary and may be denied.

Background and Rationale

Autologous iliac crest bone graft (ICBG) is regarded as the clinical gold standard for spinal fusion because it provides the three fundamental biologic properties required for fusion: osteoconduction, osteoinduction, and osteogenesis. The policy recognizes ICBG's established role while acknowledging its associated donor‑site morbidity, which has driven investigation of alternative grafts and biologic adjuncts.

Given ICBG's proven biologic properties and long history of clinical use, the policy prioritizes autograft when feasible and uses established graft extenders or substitutes only when supported by evidence or guideline‑based recommendations.

Definitions and Product Classes

Allograft — definition (MedicineNet)

DefinitionThe transplant of an organ or tissue from one individual to another of the same species with a different genotype.

Typical formsStructural cortical or corticocancellous bone used fresh-frozen or freeze-dried for spinal fusion procedures.

Regulatory noteAllografts are considered tissues for transplantation; when combined with other materials the resulting product may be regulated as a device by the FDA.

Autograft — definition (MedicineNet)

DefinitionTissue transplanted from one part of the body to another in the same individual.

Clinical roleAutograft (e.g., iliac crest harvest) provides osteoconductive, osteoinductive, and osteogenic properties and is considered the gold standard for fusion when feasible.

OpenPayer

Spinal Fusion and Bone Healing Enhancement Products (for Idaho Only)

Coverage Criteria and Evidence Summary

Applicable Codes and Regulatory Notices

Provider Requirements, Prior Authorization, and Documentation

Background and Rationale

Definitions and Product Classes