Currentsierra health and lifePolicy 2026T0605M

Vertebral Body Tethering Scoliosis

This UnitedHealthcare medical policy defines clinical and facility criteria under which vertebral body tethering (VBT) surgery and VBT revision surgery may be considered medically necessary for adolescent idiopathic scoliosis, and states that VBT is not medically necessary when criteria are not met. It applies to UnitedHealthcare Commercial and Individual Exchange benefit plans.

Policy Summary

Payersierra health and life

PolicyVertebral Body Tethering Scoliosis

Policy CodePolicy 2026T0605M

Change TypeRevised coverage with added clinical, facility, and research criteria

Effective DateApr 1, 2026

Next Review DateN/A

Key ActionDocument failed conservative management with progression to ≥45°, provide Cobb angle and bending film results, Sanders score 2–5, confirm facility/surgeon qualifications, and document research enrollment or shared decision-making per policy requirements.

SourceLink

POLICY UPDATE CHANGES

Revised coverage rationale to specify detailed clinical criteria, facility requirements, surgeon/research participation, and shared decision-making for VBT to be medically necessary.

Added/clarified facility and surgeon requirements including onsite pediatric scoliosis program, inpatient pediatric physical therapy, intraoperative advanced imaging, pediatric anesthesiologist, and pediatric ICU.

Specified revision surgery may be medically necessary for tether breakage, hardware failure, under/over-correction, or removal of hardware for complications (e.g., impingement, infection, intractable pain).

Added language indicating benefit coverage is determined by the member-specific benefit plan and that medical records documentation may be required to assess clinical criteria for coverage.

Referenced FDA labeling and Humanitarian Device Exemption for The Tether™ system and alignment with research study/IRB participation for coverage.

Added language indicating benefit coverage is determined by the member-specific benefit plan and applicable laws, and that medical records documentation may be required to assess clinical criteria for coverage.

45-65°Cobb angle range for consideration

Sanders 2-5Skeletal maturity allowed

T4-L4Instrumentation level limits

75%Larson IDE 2‑yr success

20%Reported tether breakage (typical)

Coverage Summary

This policy applies to UnitedHealthcare Commercial and Individual Exchange benefit plans and defines the clinical, facility, and practitioner requirements under which anterior vertebral body tethering (VBT) for adolescent idiopathic scoliosis may be considered medically necessary — covered with criteria (and when it is not medically necessary if criteria are not met).

Vertebral body tethering (VBT) is a fusionless growth modulation surgical technique using anterior vertebral body screws and a tensioned cord (tether) placed across the convex side of progressive adolescent idiopathic scoliosis to induce asymmetric growth modulation while aiming to preserve spinal flexibility. Evidence is evolving: prospective and registry series report that VBT can reduce Cobb angle in skeletally immature patients and preserve motion, but comparative studies and meta-analyses show VBT typically achieves less radiographic correction than posterior spinal fusion (PSF) and is associated with substantially higher rates of complications, tether breakage, revision surgery, and conversion to PSF; longer-term durability through skeletal maturity remains uncertain. Coverage is therefore limited to specific clinical thresholds and facility/surgeon/study participation or shared decision-making requirements as detailed in the policy.

Key clinical thresholds noted in the policy include preoperative curve progression after failed conservative management to at least 45°, major coronal curve Cobb angle between 45–65° for the planned instrumented curve (and no curve >65°), Sanders skeletal maturity score 2–5, bending films demonstrating correction to ≤ 30°, osseous adequacy for screw fixation, and instrumentation that does not extend above T4 or below L4. The policy also references FDA HDE labeling for The Tether™ system and requires performance in centers meeting pediatric program, imaging, anesthesia, PT, and ICU capabilities and either IRB‑approved study enrollment (investigator listed) or documented shared decision‑making.

Medically Necessary — Primary VBT for Idiopathic Scoliosis

Medically Necessary — VBT Revision Surgery

Not Medically Necessary

VBT surgery is not medically necessary when the specified clinical, facility, surgeon/research participation, or shared decision-making criteria are not met.

Not medically necessary (ALL): Any case that does not meet ALL clinical criteria, facility requirements, surgeon experience/appropriateness, and either research enrollment or documented shared decision-making as specified in the medically necessary criteria above.

Coding

Primary / Revision VBT and related spine procedure codes (reference only)CPT

0656T	Anterior lumbar or thoracolumbar vertebral body tethering; up to 7 vertebral segments.
0657T	Anterior lumbar or thoracolumbar vertebral body tethering; 8 or more vertebral segments.
0790T	Revision (e.g., augmentation, division of tether), replacement, or removal of thoracolumbar or lumbar vertebral body tethering, including thoracoscopy, when performed.
22836	Anterior thoracic vertebral body tethering, including thoracoscopy, when performed; up to 7 vertebral segments.
22837	Anterior thoracic vertebral body tethering, including thoracoscopy, when performed; 8 or more vertebral segments.
22838	Revision (e.g., augmentation, division of tether), replacement, or removal of thoracic vertebral body tethering, including thoracoscopy, when performed.
22899	Unlisted procedure, spine.

Device mentionmixed

The Tether™ Vertebral Body Tethering System

Device referenced with FDA approval under Humanitarian Device Exemption

Provider Actions & Documentation Requirements

Documentation Required

Document failed conservative management and curve progression

Document failed conservative management and documented curve progression prior to VBT. Include clinical notes showing trial and failure of nonoperative measures (e.g., bracing, observation, physical therapy) and evidence of progressive curvature reaching at least 45° prior to the initial procedure. Examples: brace wear history and compliance, interval radiographs demonstrating progression, clinician notes describing worsening symptoms or function despite conservative care.

Evidence of failed conservative management (brace, observation, PT)
Documentation of curve progression to ≥ 45° prior to surgery
Examples: brace compliance records; interval radiographic comparison

Documentation Required

Provide radiographic measurements and skeletal maturity

Provide detailed radiographic measurements and skeletal maturity assessment in the preoperative record. Include Cobb angle(s) for the planned operative major coronal curve and confirm no curve > 65°. Submit bending films demonstrating reduction of the primary curve to ≤ 30°. Report Sanders skeletal maturity score (2–5 required). Document osseous adequacy for screw fixation (vertebral body size/dimensions) and the planned levels ensuring instrumentation will not extend above T4 or below L4.

Background and Evidence Summary

VBT is intended as a fusionless growth modulation procedure that asymmetrically tethers the convex side of progressive adolescent idiopathic scoliosis to allow continued growth and preserve spinal motion. The technique aims to obtain and maintain correction by modulating growth rather than fusing segments.

The evidence base is evolving and includes prospective cohorts, registries, systematic reviews, and meta-analyses. Controlled and comparative reports and pooled analyses consistently show that while VBT can reduce Cobb angle and may better preserve range of motion and allow earlier functional recovery, PSF generally achieves greater coronal correction, better coronal balance, and substantially lower complication and reoperation rates. VBT is associated with notable risks including tether breakage, overcorrection, pulmonary and mechanical complications, and higher revision/conversion-to-fusion rates. Reported tether breakage and reoperation rates vary across studies and follow-up duration (examples: tether breakage ~20% in several series and registry analyses with cumulative rates rising through 24–36 months; systematic reviews report pooled complication rates for anterior VBT around 21–27% and reoperation rates up to ~14% overall and higher with ≥36 months follow-up).

Because of these mixed outcomes and risks, the policy’s coverage stance is covered with criteria: VBT may be medically necessary only when narrow clinical criteria, facility capabilities, surgeon experience, and either IRB‑approved research participation (investigator listed and member a study candidate using The Tether™ HDE device) or documented shared decision‑making are met. Revision VBT may be medically necessary for tether/hardware failure, under‑ or over‑correction, or removal for complications; cases not meeting the specified criteria are considered not medically necessary.

Evidence / Study	Key finding summary
Hayes evolving evidence review (2025)
Concluded new abstracts unlikely to change prior minimal support; no/unclear level of support for The Tether
Larson et al. (2024) FDA IDE study
40 pts; Sanders ≤4 or Risser ≤2; curves 40–70°; 75% success at 2 yrs (Cobb <35° & no reop); tether breakage 20%; 20% reop/10% fusion at mean 3.8 yrs
Meta-analyses (2023-2025)
PSF generally greater curve correction and fewer complications/revisions; VBT preserves motion and shorter operative metrics in some studies but higher complication and revision rates
Hayes reviews (2022, updated 2024/2025)
Concluded minimal/no change to prior support; evidence limited with high complication rates
Braun et al. (2024)
n=52; mean preop 48.6° → postop 23.2° and final 24.0° at 3.3 yrs; 8% required additional procedures; 12% required fusion
Cahill et al. (2024)
n=208; radiographic tether breakage 36%; cumulative breakage ~50% by 36 months; 28% with breakage required reop; conversion to PSF 12% with breakage vs 2% without (p=0.004)
Wong et al. (2023) systematic review
Moderate evidence VBT preserves ROM better than PSF; comparable Cobb correction with low evidence; QOL inconclusive; VBT risks include overcorrection and distal adding-on
Mariscal et al. (2023) meta-analysis
n=538; significant coronal corrections; overcorrection 8.0%; tether breakage 5.9%; reoperation 10.1%
Vatkar et al. (2023)
n=196; preop Cobb 48.5° → 20.1° final; overcorrection 14.34%; mechanical complications 27.5%; tether revision 7.85%; revision to PSF 7.88%
Newton et al. (2022) propensity-matched
n=237 VBT vs 237 PSF; at 2.2 yrs 76% VBT thoracic curve <35° vs 97.4% PSF; 16% VBT required subsequent procedures vs 1.3% PSF
Zhu et al. (2022)
n=1045 pooled; clinical success ~73%; unplanned reop ~8.66%; complications 36.8%; after >36 months PSF requirement ~7.17%
ECRI (2021)
Concluded evidence inconclusive; safe and reduces curvature through 3 yrs but lacks comparative data and skeletal maturity outcomes
Single-surgeon cohort (Meyers 2021)
Reported 3.3% major, 3.3% minor, 6.5% all-complication rate in 184 cases
Shin et al. (2021) meta-analysis
Pooled complication: 26% anterior VBT vs 2% PSF; pooled reop: 14.1% VBT vs 0.6% PSF; ≥36 mo reop 24.7% vs 1.8%

Definitions

Term	Definition
Cobb Angle
An objective, standard radiographic method to quantify scoliosis curvature; preferred for reproducibility and severity assessment (Scoliosis Research Society standard)
Lenke Classification System
System categorizing adolescent idiopathic scoliosis by curve type (1-6), with sagittal and lumbar modifiers to guide surgical planning
Institutional Review Board (IRB)
Independent ethics committee that reviews, approves, and monitors clinical research involving human participants to protect rights, safety, and welfare
Sanders Skeletal Maturity Staging System
Method assessing skeletal maturity via hand/wrist x‑rays with stages 1–8 indicating increasing maturity
Shared Decision-Making
Collaborative process where clinician and patient/family consider evidence, clinician experience, and patient values/preferences to make healthcare decisions
Tether breakage
Radiographically identified increase in adjacent screw angle >5° from the minimum over follow-up (per Cahill et al. 2024) or mechanical tether failure causing loss of correction
Clinical success
Example used in studies: Cobb angle ≤35° at latest follow-up
VBT
Vertebral body tethering: anterior, non‑fusion surgical growth‑modulation technique for idiopathic scoliosis
PSF
Posterior spinal fusion
HDE
Humanitarian Device Exemption (FDA) — regulatory pathway noted for The Tether™ system
Sanders Maturity Score
Radiographic maturity staging system frequently used to assess skeletal maturity (Sanders score) — referenced in criteria as Sanders 2–5

Thresholds & Key Metrics

Revision History

2026-04-01policy_revisedLatest

Revised coverage rationale to add detailed clinical criteria for initial VBT: failed conservative management with progression to ≥45°; Cobb angle 45–65° for planned single curve and none >65°; Sanders skeletal maturity score 2–5; bending films reduce to ≤30°; osseous adequacy for screw fixation; instrumentation limits T4–L4. Also added facility, surgeon, research enrollment and shared decision-making requirements.

2026-04-01policy_revisedLatest

Specified facility capabilities required for coverage: on-site pediatric scoliosis surgical program, inpatient pediatric physical therapy, intraoperative advanced imaging, pediatric anesthesiologist, and pediatric intensive care unit.

Policy Summary

Payersierra health and life

PolicyVertebral Body Tethering Scoliosis

Policy CodePolicy 2026T0605M

Change TypeRevised coverage with added clinical, facility, and research criteria

Effective DateApr 1, 2026

Next Review DateN/A

SourceLink

On This Page

Cobb angle of major curve: 45–65° for planned operative curve; no curve > 65°
Bending films: major curve reduces to ≤ 30°
Sanders score: 2–5 documented
Imaging or operative planning notes confirming vertebral body dimensions adequate for screws
Planned instrumented levels do not extend above T4 or below L4

Prior Authorization

Facility and surgeon qualifications required for coverage

Prior authorization is required for coverage. Confirm that the facility and operating surgeon meet required qualifications before submitting PA. The facility must demonstrate pediatric spine surgical program capabilities (see items) and the surgeon must document experience with scoliosis and VBT and that the procedure is appropriate for the patient.

Facility capabilities: on-site pediatric surgical scoliosis program; inpatient pediatric physical therapy; intraoperative advanced imaging; pediatric anesthesiologist on staff; pediatric intensive care unit
Surgeon qualifications: pediatric orthopedic spine surgeon experienced in scoliosis and VBT who has determined procedure appropriateness
Submit proof of facility and surgeon qualifications with PA request

Documentation Required

Shared decision-making or research enrollment

Document either enrollment in an IRB‑approved, prospective research study (investigator status required for the treating pediatric orthopedic spine surgeon at the pediatric spine center recruiting for The Tether™ HDE) OR a documented shared decision‑making conversation with the patient/family. Include consent forms, study enrollment documentation, or SDM notes that capture risks, benefits, alternatives (including fusion), and device HDE status when applicable.

If covered as study cohort candidate: surgeon listed as investigator on active IRB‑approved prospective study recruiting for The Tether™ HDE and member eligible for cohort
Alternatively: documented Shared Decision‑Making conversation and informed consent
Include consent forms, SDM discussion notes, and any study enrollment paperwork

Documentation Required

Indications for revision surgery

Indications for revision surgery must be documented and tied to appropriate procedure coding. Coverage for revision is limited to clinical situations such as tether/hardware failure, under‑ or overcorrection, or complications requiring removal (e.g., infection, organ impingement, intractable pain). When requesting revision authorization or payment, reference the applicable revision codes and include clinical/radiographic evidence of the indicated failure or complication.

Clinical reasons for revision: tether breakage or hardware failure; undercorrection or overcorrection; removal for complication (infection, impingement, intractable pain)
Associated codes: 0790T (thoracolumbar revision), 22838 (thoracic revision)
Attach imaging and operative findings documenting tether/hardware failure or complication

Prior Authorization

Study/investigator and IRB requirement for covered study cohort candidates

For candidates where coverage is contingent on study participation, the surgeon must be an investigator on an IRB‑approved prospective study actively recruiting for VBT using The Tether™ HDE, and the member must be a study cohort candidate. Provide documentation of IRB approval, study protocol title, investigator listing, and evidence the member meets study enrollment criteria. Coverage may be limited to patients in the covered study cohort per policy.

IRB‑approved prospective study documentation (protocol title, approval date)
Surgeon listed as investigator on study at pediatric spine center
Evidence member is a study cohort candidate and any enrollment forms

Documentation Required

Counseling and informed consent

Obtain and document informed consent and counseling that addresses risks, benefits, alternatives, expected outcomes, and device-specific information (including HDE status when applicable). Ensure the patient/family understands potential need for future revision and long‑term follow‑up. Retain signed consent in the medical record.

Signed informed consent addressing risks/benefits/alternatives and device HDE status
Counseling note documenting discussion of potential for revision and long‑term outcomes

Documentation Required

Follow-up monitoring

Follow-up monitoring after VBT is required and must be documented. Postoperative plans should include routine radiographic surveillance at intervals sufficient to assess tether integrity, curve correction, and growth modulation, and clinical assessments for pain, function, and pulmonary status. Document referrals and availability of inpatient pediatric physical therapy and postoperative specialty care.

Post‑op radiographic surveillance schedule and findings (tether integrity, curve progression/correction)
Clinical follow‑up notes for pain, function, and pulmonary status
Documentation of inpatient pediatric physical therapy participation and outpatient follow‑up plans

Denial Risk

Coverage denial if criteria unmet

Coverage will be denied if required criteria and documentation are not met. Lack of documented failed conservative management, inadequate radiographic or maturity data, missing facility or surgeon qualifications, absence of required IRB/study documentation when applicable, or failure to demonstrate osseous adequacy or appropriate instrumented levels are examples that may result in denial.

Denial triggers: no documented failed conservative care or progression to ≥ 45°; Cobb angle or Sanders score outside policy thresholds; bending films not showing reduction to ≤ 30°
Denial triggers: missing facility capabilities or surgeon qualifications; no IRB/study documentation when required; instrumentation extending above T4 or below L4

Documentation Required

Medical records documentation may be required

Medical records documentation may be requested to verify medical necessity, adherence to facility/surgeon qualifications, study enrollment status, and perioperative course. Maintain complete operative reports, imaging, growth/maturity assessments, consent forms, and SDM documentation to support coverage determinations.

Operative report, pre/post imaging, Sanders maturity score documentation
Consent forms, SDM notes, study enrollment/IRB documents (if applicable)
Facility credentialing and program capability evidence may be requested

Documentation Required

Facility and staff capability confirmation

Confirm facility and staff capabilities in advance of scheduled procedures. The facility must maintain an established pediatric scoliosis surgical program, intraoperative advanced imaging, inpatient pediatric physical therapy, pediatric anesthesiology coverage, and a pediatric intensive care unit. Ensure availability of staff experienced in pediatric perioperative care and postoperative rehabilitation.

Facility requirements: established pediatric scoliosis surgical program; intraoperative advanced imaging; inpatient pediatric PT; pediatric anesthesiologist; pediatric ICU
Staffing: experienced pediatric perioperative and rehabilitation personnel
Document availability of these capabilities in the preoperative record and with PA submission

Documentation Required

Policy revision topics to review

Policy revision topics to review and monitor should be documented by providers and facilities as appropriate. These include evolving evidence for VBT effectiveness and safety, updates to FDA or HDE labeling, changes in required study participation for coverage, and new consensus guidance on patient selection, surgical technique, and long‑term outcomes. Providers should track and incorporate policy changes into informed consent and shared decision‑making discussions.

Monitor evolving clinical evidence and guideline updates for VBT
Track FDA/HDE labeling changes and study requirements tied to coverage
Incorporate policy updates into consent/SDM materials and institutional protocols

2026-04-01policy_revisedLatest

Specified surgeon/research participation requirements: surgeon experienced in pediatric spine/VBT, listed as investigator on an IRB-approved prospective study using The Tether™ (FDA HDE) actively recruiting with member as study cohort candidate, or documentation of shared decision-making with family.

2026-04-01policy_addedLatest

Defined medically necessary indications for VBT revision surgery: tether breakage or hardware failure; under- or over-correction of curves; removal of tether/anchor screws for complications (e.g., organ impingement, infection, intractable pain).

2026-04-01administrativeLatest

Added definitions and supporting information entries for Cobb Angle, Lenke Classification System, Institutional Review Board (IRB), Sanders Skeletal Maturity Staging System, and Shared Decision-Making (administrative/clarifying).

documentation_clarificationLatest

Added language that benefit coverage is determined by the member-specific benefit plan and that medical records documentation may be required to assess clinical criteria for coverage (non-material clarification).

evidence_updateLatest

Policy references and evidence sections updated to reflect evolving and mixed clinical evidence on VBT effectiveness and complication/revision rates versus PSF; studies cited include prospective IDE and multiple systematic reviews/meta-analyses (supporting detail added).