Distraction Osteosynthesis — CPB 0220 | AETNA Coverage Update

TL;DR: Aetna, a CVS Health company, modified CPB 0220 covering distraction osteosynthesis, effective February 27, 2026. Billing teams need to verify selection criteria against the updated medical necessity thresholds before submitting claims for CPT codes 20690, 20692, 20696, 27113, 27458, and 27465.

Aetna Distraction Osteosynthesis Coverage Policy: Medical Necessity Requirements 2026

The Aetna distraction osteosynthesis coverage policy under CPB 0220 Aetna sets strict two-part selection criteria. Every claim you submit for CPT codes 20690, 20692, 20693, 20694, 20696, or 20697 must satisfy both parts — not one, both.

The first part requires the member to have at least one qualifying indication: angular or rotational deformities of long bones, bone defects with or without deformity, or limb length discrepancies with or without deformity. That's the "what" the patient has.

The second part is where most claims run into trouble. The patient must also meet at least one specific severity or failure-of-treatment threshold. Know these numbers cold:

That nonunion pathway is the one that catches billing teams off guard. You need documented failure of two prior interventions — electrical stimulation and bone grafting — before the Ilizarov method is medically necessary under this policy. If your documentation only shows one failed treatment, Aetna will deny the claim. Pull your records before you bill.

The policy also covers two alternatives. Femoral shortening via CPT 27465 is an acceptable treatment for lower extremity length discrepancies greater than 2.5 cm (1 inch) that limit function. The PRECICE intramedullary limb lengthening system, billed with CPT 27113 or 27458, is covered for tibia and femur lengthening when the leg length discrepancy exceeds 4 cm. For upper extremity cases involving the humerus, CPT 0594T covers osteotomy with insertion of an externally controlled intramedullary lengthening device.

Prior authorization requirements for distraction osteosynthesis vary by Aetna plan. Check the specific member's plan before scheduling. Intramedullary devices in particular often trigger prior auth review. Don't assume an authorization for one approach covers another.

Reimbursement under this policy is contingent on meeting every criterion in writing. Aetna auditors will look for the specific discrepancy measurements and the documented treatment failures in your clinical notes. If the note says "limb length discrepancy" without a measurement in centimeters, that's a denial waiting to happen.

Aetna Distraction Osteosynthesis Exclusions and Non-Covered Indications

Four specific interventions are explicitly classified as experimental, investigational, or unproven under this policy. Billing for any of these under Aetna will result in claim denial.

Ilizarov method for other indications. If the clinical indication doesn't fall into the three covered categories — angular/rotational deformity, bone defect, or limb length discrepancy — Aetna considers the procedure experimental. This is a catch-all, but it's a real one. Unusual indications that seem analogous but aren't listed will get denied.

Intramedullary skeletal kinetic distractor (ISKD). This device is not the same as the PRECICE system. The ISKD and PRECICE are both intramedullary limb lengthening devices, but Aetna covers the PRECICE and not the ISKD. If your surgeon uses an ISKD and you bill it the same way as a PRECICE procedure, expect a denial and a potential compliance issue. Confirm the exact device before submitting.

Pulsed ultrasound as adjuvant therapy for distraction osteogenesis. CPT 20979 — low intensity pulsed ultrasound to aid bone healing — is explicitly not covered for this indication. Even if your team uses it as a supplement to a covered Ilizarov or PRECICE procedure, Aetna will not pay for 20979 in this context. Remove it from your charge capture for distraction osteogenesis cases.

Phenix nails (implantable magnetically activated nails). These are listed by name as experimental. If your facility recently added Phenix nails to the implant formulary, do not bill Aetna expecting coverage. The clinical evidence Aetna reviewed did not support coverage.

Cosmetic use is a hard exclusion. Using the Ilizarov method to correct short stature is classified as cosmetic, not medically necessary. Diagnosis codes like E23.0 (pituitary dwarfism) or E34.30–E34.39 (short stature due to endocrine disorder) will trigger cosmetic denial if the clinical record shows the goal is height gain rather than correction of a functional deformity. This is not a gray area — it's stated explicitly in the policy.

Coverage Indications at a Glance

Aetna Distraction Osteosynthesis Billing Guidelines and Action Items 2026

The effective date of February 27, 2026 is already here. If you haven't audited your active distraction osteosynthesis cases against this updated coverage policy, do it today.

CPT, HCPCS, and ICD-10 Codes for Distraction Osteosynthesis Under CPB 0220

Covered CPT Codes (When Selection Criteria Are Met)

Not Covered / Experimental Codes

Key ICD-10-CM Diagnosis Codes

The policy references 167 total ICD-10-CM codes. The full list covers fracture codes across all long bones, congenital and acquired limb deformities, and short stature diagnoses. Map your diagnosis codes carefully — the cosmetic exclusion turns on the underlying diagnosis, not just the procedure.