Bone Graft Substitutes - (0118) — MM 0118 | CIGNA Coverage Update

TL;DR: Cigna Healthcare modified MM 0118, its bone graft substitutes coverage policy, effective February 14, 2026. Here's what changes for billing teams.

Cigna Healthcare updated MM 0118 to clarify how bone graft substitutes are classified — specifically, whether they count as implants or surgical supplies. That distinction drives reimbursement, claim denial risk, and how you document medical necessity. The policy directly affects CPT codes including 20999, 27899, 21208, 21210, and a range of unlisted musculoskeletal procedure codes across nearly every body region.

Quick-Reference Table

Cigna Bone Graft Substitutes Coverage Criteria and Medical Necessity Requirements 2026

The core of this Cigna bone graft substitutes coverage policy comes down to one question: is the material an implant or a surgical supply? The answer changes how you bill, how you document, and whether you get paid.

Cigna's updated position is clear. Most bone graft substitutes — including allograft materials, bone void fillers (with or without antibiotics), synthetic materials, and recombinant bone morphogenetic proteins — do not meet the definition of an implant. Cigna classifies them as surgical supplies.

Cigna defines an implant as a device or material placed into a surgically or naturally formed body cavity to continuously assist, restore, or replace the function of an organ system or structure throughout its useful life. That definition covers stents, artificial joints, shunts, plates, screws, anchors, radioactive seeds, and non-soluble or solid plastic materials used to augment tissue or fill areas removed surgically or traumatically.

Resorbable materials fail that test entirely. The FDA classifies certain materials — such as resorbable calcium salt bone void fillers — as resorbable. Cigna follows that FDA classification. Over time, these materials dissolve and bone tissue replaces them. Because they don't persist and don't continuously restore function, they aren't implants under MM 0118.

This matters for medical necessity documentation. If your operative notes describe a bone graft substitute in language that implies it's functioning like a permanent implant, expect scrutiny. Your documentation should reflect the material's resorbable nature. Cigna's reviewers will use that distinction to determine coverage status and reimbursement.

Prior authorization requirements for bone graft substitute procedures depend on the specific plan and the procedure code used. For unlisted procedure codes — 20999, 27899, 21208, 21210, and the full list of unlisted codes under this policy — prior auth is especially important. Unlisted codes already carry elevated denial risk. When you combine an unlisted code with a material Cigna may classify as a supply rather than an implant, you're in territory where a prior authorization conversation with Cigna before the procedure is not optional — it's necessary.

Cigna Bone Graft Substitutes Exclusions and Non-Covered Indications

Eleven of the 14 codes under MM 0118 are flagged as Considered Experimental/Investigational/Unproven when used for certain indications. This is the part of the policy your billing team needs to read carefully.

Cigna treats bone graft substitutes — including recombinant human bone morphogenetic proteins (rhBMP) — as experimental or investigational in a wide range of off-spine or non-standard applications. The unlisted procedure codes are the clearest signal. When Cigna lists codes like 23929 (shoulder), 24999 (humerus or elbow), 25999 (forearm or wrist), 27299 (pelvis or hip), 27599 (femur or knee), and 29999 (arthroscopy) in the experimental group, they're drawing a hard line.

The same applies to codes 31299 (accessory sinuses), 21499 (head), 21208 (facial bone augmentation), and 21210 (nasal, maxillary, or malar bone graft). These are not routine Cigna bone graft substitutes billing scenarios. If your practice performs these procedures with bone graft substitutes and bills under these codes, you need a documented clinical rationale that directly addresses why the use is not experimental. That documentation needs to be in the chart before the claim goes out — not assembled after a denial.

The two hematopoietic codes, 38232 (bone marrow harvesting, autologous) and 38241 (HPC autologous transplantation), also carry the experimental designation in this context. If your billing team hasn't separated out the bone graft substitute use case from standard oncology billing under those codes, now is the time to build that distinction into your charge capture workflow.

Coverage Indications at a Glance

Cigna Bone Graft Substitutes Billing Guidelines and Action Items 2026

The effective date of February 14, 2026 means this policy is already active. If you haven't audited your claims workflow against MM 0118 in the Cigna system, start today.

CPT, HCPCS, and ICD-10 Codes for Bone Graft Substitutes Under MM 0118

Unlisted Procedure Codes — Standard Billing (When Medical Necessity Criteria Are Met)

Experimental / Investigational / Unproven Designations

These codes carry an experimental/investigational/unproven designation under MM 0118 when used with bone graft substitutes. High denial risk without documented clinical justification.

No ICD-10-CM codes are listed in the MM 0118 policy data. Diagnosis code selection should reflect the underlying condition requiring bone grafting and align with your operative documentation.