Sacroiliac Joint Interventions (for Kentucky Only)

Coverage Summary

This UnitedHealthcare Kentucky policy defines positions for intraarticular sacroiliac (SI) joint injections, sacral lateral branch nerve blocks (diagnostic), and sacroiliac joint fusion — both minimally invasive and open approaches — and references InterQual clinical criteria for specific medical necessity determinations. The policy explicitly does not address radiofrequency ablation of the SI joint (that treatment is covered under a separate Ablative Treatment for Spinal Pain policy).

Coverage stance is mixed: intraarticular SI joint injections and sacroiliac joint fusions are considered medically necessary in certain circumstances when InterQual (and specified) criteria are met, whereas sacral lateral branch nerve blocks used as a diagnostic tool prior to radiofrequency ablation are considered unproven and not medically necessary due to insufficient evidence.

Key thresholds and quick facts

Required diagnostic intra-articular SIJ block response>= 75% reduction of pain for the expected duration of the anesthetic on two separate occasions

Minimum nonoperative/conservative treatment duration prior to SIJ fusionAt least 6 months of intensive nonoperative treatment

Required number of diagnostic SIJ blocks1 (at least one image-guided, diagnostic intra-articular SIJ block required)

ISASS pain severity thresholdPain rating >= 5 on 0-10 numeric rating scale

Minimum conservative therapy duration (general)>= 6 months

Medical Necessity Criteria

SI Joint Injections

Refer to InterQual CP: Procedures, Sacroiliac (SI) Joint Injection for medical necessity clinical coverage criteria.

Intraarticular SI joint injections are proven and medically necessary in certain circumstances per InterQual criteria

Provider must follow InterQual CP for specific inclusion/exclusion and documentation

Sacral Lateral Branch Nerve Blocks (Diagnostic)

Policy position

Sacral lateral branch nerve blocks as a diagnostic tool prior to radiofrequency ablation are unproven and not medically necessary due to insufficient evidence of efficacy

Sacroiliac Joint Fusion (SIJF)

Refer to InterQual CP: Procedures, Sacroiliac (SI) Joint Fusion (and Client Defined CP: Procedures Sacroiliac (SI) Joint Fusion (Custom) - UHG) for medical necessity clinical coverage criteria.

Coding

Referenced Procedure CPT codesCPT

27278	Arthrodesis, sacroiliac joint, percutaneous or minimally invasive, with image guidance, includes obtaining bone graft when performed, unilateral; placement of intra-articular device(s), with cortical piercing
27279	Arthrodesis, sacroiliac joint, percutaneous or minimally invasive, with image guidance, includes obtaining bone graft when performed, unilateral; placement of transarticular device(s) and/or intra-articular device(s) piercing the lateral or medial cortices of the ileum and the lateral cortex of the sacrum
27280	Arthrodesis, sacroiliac joint, open, includes obtaining bone graft, including instrumentation, when performed
64451	Injection(s), anesthetic agent(s) and/or steroid; nerves innervating the sacroiliac joint, with image guidance (i.e., fluoroscopy or computed tomography)

Applicable CPT codes (updated list)CPT

27278	Procedure code included; description revised per policy history.
27279	Procedure code included; description revised per policy history.

Provider Actions / Prior Authorization & Documentation

Prior Authorization

Follow InterQual for authorization

InterQual criteria are required for medical necessity determinations and authorizations for SI joint injection and/or SI joint fusion. Providers must reference and meet the InterQual CP criteria as the basis for coverage decisions and prior authorization.

Prior Authorization

Preauthorization/documentation of diagnostic SIJ block

Preauthorization requires documentation that pain was confirmed with a fluoroscopically guided diagnostic intra-articular SIJ block using local anesthetic prior to considering minimally invasive SIJ fusion. The policy requires an image-guided, contrast-enhanced intra-articular SIJ injection with documented response as part of the medical necessity criteria for fusion.

Background, Evidence & Definitions

Scope/background: This policy addresses intraarticular SI joint injections and sacroiliac joint fusion (minimally invasive and open) and does not cover radiofrequency ablation of the SI joint (see Ablative Treatment for Spinal Pain policy for RFA). It provides definitions (e.g., provocative tests, SIJ fusion approaches, Titanium Triangular Implant) and requires use of InterQual CP criteria for medical necessity determinations.

Evidence and guideline context: The policy cites multiple systematic reviews, randomized controlled trials, and technology assessments showing efficacy evidence for minimally invasive SIJ fusion—particularly for triangular titanium implant systems (e.g., iFuse) — including RCTs (INSITE and others), meta-analyses (Ghaddaf et al. 2024; Whang et al. 2023), and longer-term cohort data. It also notes that evidence for alternative implants (cylindrical threaded implants, engineered bone allografts, LinQ) is limited or of lower quality (Hayes, ECRI) and that professional guidance (NASS, ISASS, ASPN, NICE) includes specific diagnostic and treatment criteria that the policy incorporates or references.

Evidence	Summary
Ghaddaf et al. (2024) meta-analysis	Systematic review/meta-analysis of MISIJ fusion using triangular titanium implants (TTI) vs nonoperative management (3 trials, 423 participants) showing significant reductions in pain and ODI and decreased opioid use; adverse event rates not higher than nonoperative care.
Whang et al. (2023)	Systematic review and random-effects meta-analysis of 57 cohorts (2,851 individuals) found lateral transiliac (LTI) procedures had superior efficacy; only LTI (iFuse) has Level 1 evidence and independent radiographic fusion confirmation; adverse events infrequent.
Polly et al. (2016, INSITE RCT)	Randomized controlled trial reporting significant improvements in pain and ODI at 24 months for iFuse vs conservative care; reduced opioid use and device/procedure–related adverse events reported; limitations include crossover and lack of sham control.
ECRI / Hayes reviews	Evidence assessments report stronger evidence for the iFuse triangular titanium implant (reduces pain and improves QOL vs nonsurgical care) and limited/very-low-quality or unclear evidence for cylindrical threaded implants and engineered bone allografts; call for more comparative trials.
Systematic reviews / multiple RCTs and cohorts	Multiple systematic reviews, cohort series, and randomized trials support MIS SIJ fusion efficacy particularly for TTI/iFuse; evidence for other implant systems is limited, heterogeneous, and generally lower quality.

Term	Definition
Provocative Tests	Physical maneuvers (e.g., thigh thrust, compression, Gaenslen's, distraction, Patrick's/FABER) performed to reproduce typical SI region pain.
Sacroiliac Joint Fusion (Arthrodesis)	Surgical procedure intended to join the sacrum and iliac bones to stabilize the joint, via minimally invasive (percutaneous) or open approaches, with the goal of alleviating or reducing low back pain.
Titanium Triangular Implant	An SIJ implant (e.g., iFuse) intended for sacroiliac joint fusion for conditions including SIJ disruptions and degenerative sacroiliitis; used in minimally invasive lateral transiliac approaches.

Revision History

04/01/2026material_changeLatest

Archived previous policy version CS200KY.13; Updated list of applicable CPT codes to reflect annual edits; revised description for 27278 and 27279.