Minimally Invasive Arthrodesis of the Sacroiliac Joint (SIJ)

LCD Information Document Information Source LCD ID N/A LCD ID L39797 Original ICD-9 LCD ID Not Applicable LCD Title Minimally Invasive Arthrodesis of the Sacroiliac Joint (SIJ) Proposed LCD in Comment Period N/A Source Proposed LCD DL39797 Opens in a new window Original Effective Date For services performed on or after 04/17/2025 Revision Effective Date For services performed on or after 04/17/2025 Revision Ending Date N/A Retirement Date N/A Notice Period Start Date 01/02/2025 Notice Period End Date 04/16/2025 CPT codes, descriptions, and other data only are copyright 2025 American Medical Association. All Rights Reserved. Fee schedules, relative value units, conversion factors and/or related components are not assigned by the AMA, are not part of CPT, and the AMA is not recommending their use. The AMA does not directly or indirectly practice medicine or dispense medical services. The AMA assumes no liability for data contained or not contained herein. 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Issue Issue Description This LCD outlines limited coverage for this service with specific details under Coverage Indications, Limitations and/or Medical Necessity. Issue - Explanation of Change Between Proposed LCD and Final LCD Clarifying language was added to the final LCD to distinguish the 2 procedures. The final LCD included the results of the 12-month SECURE study as well as societal guidelines and assessment of those guidelines. Additional literature provided in the Response to Comments was added. Finally, further clarification was added to the Analysis of Evidence. CMS National Coverage Policy Title XVIII of the Social Security Act (SSA), §1862(a)(1)(A) excludes expenses incurred for items or services which are not reasonable and necessary for the diagnosis or treatment of illness or injury or to improve the functioning of a malformed body member. Coverage Indications, Limitations, and/or Medical Necessity Covered Indications Minimally Invasive (MI) Arthrodesis of the sacroiliac joint (SIJ) WITH placement of a transfixation device is considered medically reasonable and necessary when ALL of the following criteria are met: Patient must meet all requirements for coverage as outlined in Sacroiliac Joint Injections and Procedures L39402 including: At least 1 diagnostic block with ≥75% reduction of pain as defined in L39402 AND A trial of at least 1 therapeutic intra-articular SIJ injection (i.e., corticosteroid injection that results in a ≥50% reduction of pain for the expected duration of the injected agent AND Diagnostic imaging studies that include ALL the following: Imaging (plain radiographs and a computed tomography (CT) or magnetic resonance imaging (MRI)) of the SIJ that excludes the presence of destructive lesions (e.g., tumor, infection), fracture, traumatic SIJ instability, or inflammatory arthropathy that would not be properly addressed by percutaneous SIJ fusion (SIJF) Imaging of the pelvis (anteroposterior (AP) plain radiograph) to rule out concomitant hip pathology Imaging of the lumbar spine (CT or MRI) to rule out neural compression or other degenerative condition that can be causing low back or buttock pain B. MI Arthrodesis of the SIJ WITHOUT placement of a transfixation device is NOT considered medically reasonable and necessary. Limitations: Absence of generalized pain behavior (e.g., somatoform disorder) or generalized pain disorders (e.g., fibromyalgia) Patient should be part of an ongoing care plan, and be actively participating in a rehabilitation program, home exercise program or functional restoration program Summary of Evidence The SIJ is a synovial or diarthrosis-amphiarthrosis joint, whose primary function is to transfer weight to and from the lower extremities to the axial skeleton.1 The SIJ has been implicated as a source of chronic LBP in 15% to 30% of patients.2 The SIJ contains both mechanoreceptors and nociceptive receptors such that SIJ pathology leads to pain in the buttocks, lower back, groin or leg. SIJ degeneration commonly occurs, especially after lumbar fusion. The SIJ is particularly enigmatic in its ability to mimic hip and lumbar spine pathology and also to result from the surgical treatment of hip and spine issues.3 Patients with SIJ pain report Oswestry Disability Index (ODI) scores in the 50s and the burden of disease associated with SIJ pain is at least as high as that associated with other musculoskeletal conditions such as hip osteoarthritis, degenerative spondylolisthesis, or spinal stenosis; conditions that are often treated surgically.4 Risk factors for SIJ dysfunction may include abnormal gait, scoliosis, degenerative and inflammatory arthritis, previous lumbar spinal surgery, trauma, and childbirth.5 In addition, the SIJ may be a referred site of pain, including from a degenerative disc at L5-S1, spinal stenosis, or osteoarthritis of the hip. Diagnosis remains problematic, with no universally accepted reference standard. Current best practice diagnostic techniques start with pain provocation testing. A positive result on 3 or more pain provocation tests, such as Gaenslen’s, FABER, compression, distraction, and thigh thrust, are used as criteria for further testing to confirm the SIJ as the primary pain generator. Typically, diagnostic blocks and intraarticular fluoroscopically guided injections are then used for confirmation of SIJ disorder. A standard of ≥75% relief of pain has been suggested as an indication of pain deriving from the SIJ. X-ray, CT or MRI of the SIJ has not proven to be sensitive or specific enough to be used alone but may be helpful when used in conjunction with other diagnostic techniques. Radiographic utility lies more in excluding the presence of other causes of pain that would not be properly addressed by percutaneous SIJF.3,6,7 The mainstay of therapy for disorders of the SIJ has been nonoperative treatment, including activity modification, NSAIDs, physical therapy, radiofrequency neurotomy and SIJ injections (SIJIs). High quality clinical evidence corroborating the benefits of these non-surgical therapeutic options is limited by small patient populations, lack of placebo controls, and failure to utilize validated outcome measures.8 When these modalities fail, the International Society for the Advancement of Spine Surgery (ISASS) recommends SIJ arthrodesis.9 Surgical treatment is indicated for patients with a positive response to an SIJ injection with ≥75% relief, failure of nonsurgical treatment, and continued or recurrent SIJ pain. Traditional open SIJF procedures are complex and invasive, involving open exposure of the joint with instrumented fixation and/or bone graft harvesting, and are typically associated with lengthy hospital stays, large blood loss and prolonged recovery times. Outcomes of traditional SIJF procedures were observed to be so poor with a high rate of reported non-union that these procedures were virtually abandoned over the last few decades.10 However, in the case of revision surgery, nonunion, and aberrant anatomy, open arthrodesis should be performed.11 To review literature on devices for SIJF, PubMed® was searched using the Boolean phrase “sacroiliac joint AND (fusion OR arthrodesis)” since 2010. To establish a list of SIJF devices not represented in the literature, searches were performed on the Federal Drug Administration (FDA) 510(k), premarket approval, and De Novo databases, as well as Google and LinkedIn. Literature review yielded 11 FDA-approved devices for MI SIJF. Database query yielded an additional 22 devices for a total of 33 devices. Twenty-one devices used the lateral transiliac approach, 6 posterior allograft approaches, 3 posterolateral approaches, and 3 combined the lateral transiliac and posterolateral approaches. The evidence for the lateral transiliac approach is the most robust.12 This approach is also termed arthrodesis with placement of a transfixation device. Arthrodesis of the Sacroiliac Joint (SIJ) Utilizing Intra-articular and/or Transarticular Device(s) with Cortical Piercing More recently, MI techniques with novel implants have been developed that are designed to confer the benefits of permanent SIJ stabilization but with a more reasonable safety profile. These devices are presently termed transfixation devices by the American Medical Association (AMA) and transverse devices by the American Society for Testing and Materials (ASTM) and the procedure is NOT defined by the directionality of the approach. New language to CPT®, as of 2026, will distinguish this approach as the placement of intra-articular and/or transarticular device(s) that pierce the lateral or medial cortices of the ilium and the lateral cortex of the sacrum. However, most published data describing this procedure terms this a lateral transfixing approach. While a small number of studies describe use of hollow modular anchor screws, a larger number describe use of triangular titanium implants (TTIs) with a porous surface. These implants serve to minimize rotation and maximize surface area at the SIJ. Kube and Muir14 evaluated 1 year clinical results from a cohort of 18 patients with SIJ pain unresponsive to conservative treatment who underwent minimally invasive surgical (MIS) SIJFs. At 12 months, the overall fusion rate was 88%. Back and leg pain improved from 81.7 to 44.1 points on the visual analog scale (VAS) (p<0.001) and from 63.6 to 27.7 points (p<0.001), respectively. Disability scores improved from 61.0 to 40.5 (p<0.009) on the ODI. No major complications were reported. This small prospective cohort study is limited by small sample size, lack of control, short-term follow-up and mean age (47.2) well below Medicare population. Similar results were noted by Rainov et al.15 in their retrospective study of 160 patients with painful SIJ dysfunction who underwent unilateral or bilateral SIJF using TTIs. By 12 months, pain decreased from 8.0 to 2.5 (VAS) (p<0.0001) and disability (ODI) from 45.3 to 16.4 (p<0.001). Limitations include lack of randomization and controls, missing outcome data including high loss to follow-up by 12 months (90/160), mean age below Medicare population (58), risk of bias, and short-term follow-up. A prospective multicenter single arm interventional trial looking at 172 subjects with MIS for SIJ dysfunction was conducted by Duhon et al.16 Diagnosis of SIJ pain was confirmed with diagnostic injections requiring a 50% decrease in pain. Patients completed VAS and ODI assessments preoperatively, and at 1, 3, 6, and 12 months postoperatively. Patient satisfaction with surgery was also assessed at 6 and 12 months. Mean VAS improved from 79.8 at baseline to 30.0 and 30.4 at 6 and 12 months, respectively. Mean ODI improved from 55.2 at baseline to 32.5 and 31.4 at 6 and 12 months. At 6 and 12 months, 93 and 87% of subjects, respectively, were somewhat or very satisfied and 92 and 91%, respectively, would have the procedure again. Follow-up at 24 months demonstrated sustainability of quality-of-life scores using EuroQol-5 Dimension (EQ5D), as well as a decrease from 76.2% at baseline of opioid usage to 55.0% at 24 months (p<0.0001). CT scan at 1 year demonstrated a high rate of bone adherence (97%) to at least 2 implants on both the iliac and sacral sides with modest bone growth across the SIJ.17 Of severe adverse events (AEs) 4/29 were probably or definitely device related. Strength includes predetermined eligibility criteria, use of standardized pain assessments at each study point and 24-month follow-up. Limitations include lack of randomization and controls, enrollment was not consecutive, and mean age below Medicare population (50.9). Polly et al.18 described 2-year outcomes from a multicenter randomized controlled trial (RCT) of MIS vs non-surgical management (NSM) for SIJ dysfunction. One hundred and forty-eight subjects with SIJ dysfunction were randomly assigned to MI SIJF with TTIs (SIJF, n=102) or (NSM, n=46) after diagnostic injections requiring a 50% decrease in SIJ pain. SIJ pain score utilizing VAS, disability score utilizing ODI and quality of life (QOL) EQ5D scores were collected at baseline and at scheduled visits to 24 months. In the SIJF group, mean SIJ pain improved rapidly and was sustained (mean improvement of 55.4 points) at month 24. The 6-month mean change in the NSM group (12.2 points) was substantially smaller than that in the SIJF group (by 38.3 points, p<0.0001 for superiority). By month 24, 83.1% and 82.0% received either clinical improvement or substantial clinical benefit, respectively, in VAS SIJ pain score. Similarly, 68.2% and 65.9% had received clinical improvement or substantial clinical benefit in ODI score at month 24. In the NSM group, these proportions were <10%. The rate of AEs related to SIJF was low and only 3 subjects assigned to SIJF underwent revision surgery within the 24-month follow-up period. Strengths of the study include randomization, control group, and 24-month follow-up. Limitations include lack of blinding, high cross-over at 6 months (n=39) limiting data to short-term results, risk of bias including study sponsorship by manufacturer of device, mean age below Medicare mean (51.3) and majority of participants Caucasian (95.3%) limiting generalizability. In a long-term (3-year) follow-up, MI trans-iliac SIJF with TTIs continued to be associated with improved pain, disability, and QOL with relatively high satisfaction rates.19 Subjects included in this Long-Term Outcomes Study (LOIS) were enrolled at 12 centers who participated in either INSITE or SIFI. INSITE is a prospective multicenter randomized trial of SIJF vs. NSM whose 2-year results showed high degrees of improvement in pain, disability and QOL in the surgical group but only modest responses in the non-surgical group. SIFI is a prospective multicenter single-arm clinical trial evaluating the same procedure/device; the follow-up schedule and assessments were nearly identical, and 2-year results were similarly positive. Study follow-up in LOIS consisted of phone calls postoperatively at years 2.5, 3.5, and 4.5 as well as in-clinic study visits at years 3, 4, and 5. Phone calls were intended to maintain subject contact and assess for AEs. At in-clinic visits, subjects completed surveys to assess SIJ pain and LBP scores (VAS), ODI, QOL (EQ5D) time trade-off (TTO) index, and satisfaction. All questionnaires were administered by trained study research coordinators. Of 127 potentially eligible INSITE/SIFI subjects, 103 were enrolled in LOIS. Mean preoperative SIJ pain score was 81.5 and mean preoperative ODI was 56.3. At 3 years, mean SIJ pain score decreased to 26.2 (a 55-point improvement from baseline, p<0.0001). At 3 years, mean ODI decreased to 28.2 (a 28-point improvement from baseline, p<0.0001). In all, 82% of subjects were very satisfied with the procedure at 3 years. EQ5D TTO index improved by 0.30 points (p<0.0001). No AEs definitely related to the study device or procedure were reported. Strength of the study includes 3-year follow-up. Limitations include mean age below Medicare mean (51) and majority of participants Caucasian (97%) limiting generalizability, risk of bias including recall and conflicts of interest, and missing outcome data including the control group with high cross-over rate. A comparative 6-year retrospective case series by Vanaclocha et al.20 looked at MIS, radiofrequency denervation and conservative management (CM) for SIJ pain. The study was not randomized, and some patients were unable to undergo radiofrequency ablation (RFA) or MIS due to insurance reasons, so there was a pool of patients who had CM only. Out of the 152 patients who had a positive response to SIJ infiltration, 74 continued with CM, 51 underwent SI denervation and 27 underwent SIJF. In the CM group, 63 patients had 1-yr follow-up, and 2-, 3-, 4-, 5-, and 6-yr follow-up was available in 52, 43, 34, 23, and 16 patients, respectively. In the SI denervation group, 47 had 1-yr follow-up and further follow-up (same time points) was available in 41, 33, 23, 6, and 2 patients. In the SIJF group, 27 patients had 1-year follow-up and further follow-up was available in 24, 20, 15, 6, and 1 patient. Pain relief was seen at 1 month after CM, SI denervation, and SIJF. However, pain returned to near baseline levels in the CM and SI denervation groups with further follow-up. In contrast, SIJ pain remained low postoperatively in the SIJF group. At 6 months and beyond, the mean difference in pain improvement between the CM and SIJF groups was approximately 6 points (repeated measures analysis of variance, P<0.001), and the difference between the SI denervation and SIJF groups was approximately 4.5 points (P<0.001). Similar findings were seen with ODI, which showed improvement after SI infiltration but return of high scores within 6 months. ODI scores improved substantially after SIJF but returned to baseline levels in the CM and SI denervation groups. Mean ODI differences beyond 6 months were as follows: SIJF vs CM, 24 points (P<0.001); SIJF vs SI denervation, 17 points (P<0.001). No patient in the CM and SI denervation groups had an improvement in ODI of at least 15 points at year 4; in contrast, all SIJF patients showed at least a 15-point improvement at year 4 (P<0.001). Limitations include lack of randomization or controls, missing outcome data inherit to retrospective studies, variability in cohorts including duration of follow-up with mean of 4 years. There are other approaches in addition to the lateral approach that still result in transfixation rather than distraction. Raikar21 reported on a small series of 19 patients aged 44-84 years, with a median of 58 years, underwent SIJF using this technique. The follow-up is between 7 and 30 months, with a median of 12 months. Eighteen patients had excellent pain relief. There was no complication from the procedure, and the blood loss was minimal. All 8 patients who had follow-up radiographs showed solid fusion. With the posterior oblique approach described in this paper, the screw entry point is on the upper outer surface of the iliac crest. This negates the need to dissect through the gluteal fascia to reach the ileum. This decreases the risk of injury to the superior gluteal neurovascular structures and the cuneal nerves. It also makes it a relatively bloodless procedure, which can be performed in an outpatient setting. This contrasts with the lateral approach in which the average blood loss has been reported to be between 31 and 42.8 cc, and with an average length of stay between 0.8 and 1.9 days.15,16 The posterior oblique approach also allows the surgical trajectory to remain within the ileum and sacrum, resulting in minimal soft tissue manipulation. In the straight posterior approach in which a bone plug is inserted into the joint, there is distraction of the joint.19 This contrasts with the posterior oblique approach, in which the screws decrease movement in the joint by bringing the joint surfaces together. Theoretically, bringing the joint surfaces together should be more effective in decreasing pain because there is less room for movement within the joint. In addition, in the posterior approach, because the joint space is expanded, the bone graft may move, if fusion does not occur. Arthrodesis of the SIJ Utilizing Intra-articular Device(s) that do not pierce the cortices of the ilium or sacrum The procedures that are presently termed non-transfixation approaches, or intra-articular approaches by the AMA and In-line approaches by the AST. Rather than transfixing the SIJ, these procedures utilize distraction arthrodesis. Again, these are NOT defined by directionality, but the vast majority are usually performed from a dorsal (posterior) approach. At times these are combined into dorsa-lateral approach. New language to CPT®, as of 2026, will distinguish this approach as percutaneous or minimally invasive, with image guidance, and includes obtaining bone graft when performed with placement of intra-articular device(s), without cortical piercing Throughout the literature review, this approach is often termed a non transfixation approach and is often referred to by directionality. That does NOT mean the procedure itself is limited by directionality. MI posterior SIJF was first introduced as a procedure in 2008 for the treatment of SIJ dysfunction. This procedure attempts to stabilize the SIJs by fusing the sacrum to the ilium with allograft material, limiting movement of the joint.22 The posterior (dorsal) SIJF procedure is distinct from lateral trans-iliac MI SIJF using transfixing devices in several ways9: The surgeon’s work effort is distinct with the dorsal procedure requiring less surgical dissection, and the procedure generally takes less time. Initial stabilization is not achieved via transfixation with a laterally placed device, but rather by tensioning of the ligaments supporting the SIJ via placement of a bone graft or allograft implant. Long-term stabilization or fusion is achieved via distraction arthrodesis rather than by integration of the surrounding bone of the ilium and sacrum. Distraction arthrodesis of the SIJ consists of placement of an implant or bone allograft into the ligamentous portion of the SIJ, this places the supporting ligaments under tension. Bone graft and/or recombinant human bone morphogenetic protein are utilized to achieve bone fusion. Placement of SIJF allograft implants via a posterior approach is intended to be less invasive and avoid risks associated with encountering the neurovascular bundle.23 Examples of posterior SIJ stabilization devices are CornerLoc Opens in a new window™ (Foundation Fusion Solutions, LLC.), TransFasten Opens in a new window™ (Captiva Spine®), and LinQ Opens in a new window™ (PainTEQ). Based on the FDA's criteria for determining whether a structural allograft averts regulatory oversight and classification as a drug/device/biologic, mineralized bone allografts were judged to meet the Agency's definitional descriptions for minimal manipulation and homologous use when complying with the American Association of Tissue Banks’ (AATB) accredited guidelines for bone allograft harvesting, processing, storing and transplanting. Thus, these products do not require FDA medical device clearance. Radiographic fusion rates achieved with mineralized bone allografts were uniformly high (>85%) across 3 published systematic reviews. Little variation was found in the fusion rates irrespective of anatomical location, allograft geometry, dimensions or indication, and in most cases, the rates were similar to those for autologous bone alone.24 The non-transfixation approach aims to reduce neurological complications by avoiding the sacral foramen, passes through and manipulating less soft tissue, avoiding nervous and arterial structures, and decreasing post-op recovery time. Unlike the lateral approach which typically requires patients to undergo general anesthesia, and can be performed under conscious sedation with local anesthetic, typically an outpatient day surgery procedure.25 Initial research of this method was first conducted on cadavers. Six cadaveric SIJ specimens were tested under intact, unilateral fixation, and bilateral fixation conditions. The total range of motion (ROM) of the SIJ in flexion-extension, lateral bending, and axial rotation were evaluated by an optical tracking system, in a multidirectional flexibility pure moment model, between +/- 7.5 Nm applied moment loads. The centers of the instantaneous axis of rotation (cIAR) of the SIJ were evaluated during flexion-extension loading. A correlation analysis was performed between the ROM reduction in flexion-extension upon implantation and shift of the cIAR to the graft implantation site. RESULTS: Unilateral and bilateral fixations generated SIJ ROM reductions in flexion-extension, lateral bending, and axial rotation motions. Fixation shifted the cIAR to the graft implantation site. Reduction in the total ROM had a moderate correlation with the shift of the cIAR. The conclusion was that the novel posterior approach presented a multifaceted mechanism for stabilizing the joint: first, by the reduction of the total ROM in all planes of motion; second, by shifting the centers of the cIAR towards the implant's location in the predominant plane of motion, ensuring little to no motion at the implantation site, thus promoting fusion in this region.26 During flexion–extension, the posterior approach is equivalent to the lateral approach, while producing superior stabilization during lateral bend and axial rotation.27 Deer et al.25 conducted a multicenter retrospective observational study of patients with refractory SIJ pain treated by interventional pain physicians at 1 of the 8 different pain management centers. A total of 111 patients were included in the study and underwent posterior SIJF via the LinQ™ SIJF procedure for refractory SIJ-related pain following the use of spinal cord stimulation (SCS), interspinous spacer (ISS), intrathecal drug delivery (IDDS), and/or minimally invasive lumbar decompression (MILD). Overall, the mean patient reported pain relief following posterior SIJF was 67.6%. In patients with a history of failed back surgery syndrome, the mean patient reported pain relief was 76.5%. In this retrospective case series of patients with continued intolerable pain following SCS, ISS, IDDS, or MILD, the posterior SIJF device provided significant pain relief in a salvage manner.25 Limitations include lack of randomization and controls, short-term follow-up, and risk of bias, while strength includes inclusion of Medicare age population with mean age 69.8. Caheuque et al.28 conducted a retrospective cohort study that analyzed data from 45 patients who underwent SIJF. Included patients were >/=50 years old, nonresponsive to conservative treatment. Subjects were divided into 2 cohorts based on the SIJF technique. Primary outcomes were pain relief, measured by VAS, and functional improvement, determined by the ODI; both were recorded and assessed at baseline, postoperative, and the change from pre- to postoperative. Additionally, data regarding patient demographics, previous lumbar fusion, operative time, and duration of hospital stay were collected and analyzed. Baseline demographic and clinical variables exhibited no significant differences in distribution between groups. The posterior oblique cohort demonstrated a substantial reduction in operative time (over 50%) and duration of hospital stay compared to lateral cohort. Pain relief (postoperative VAS: lateral 3.5+/-1.7 vs. posterior oblique 2.4+/-1.5 [p=0.02]) and functional improvement (postoperative ODI: lateral 29.6+/-7.3 vs. posterior oblique 21+/-5.7 [p

Covered Indications Minimally Invasive (MI) Arthrodesis of the sacroiliac joint (SIJ) WITH placement of a transfixation device is considered medically reasonable and necessary when ALL of the following criteria are met: Patient must meet all requirements for coverage as outlined in Sacroiliac Joint Injections and Procedures L39402 including: At least 1 diagnostic block with ≥75% reduction of pain as defined in L39402 AND A trial of at least 1 therapeutic intra-articular SIJ injection (i.e., corticosteroid injection that results in a ≥50% reduction of pain for the expected duration of the injected agent AND Diagnostic imaging studies that include ALL the following: Imaging (plain radiographs and a computed tomography (CT) or magnetic resonance imaging (MRI)) of the SIJ that excludes the presence of destructive lesions (e.g., tumor, infection), fracture, traumatic SIJ instability, or inflammatory arthropathy that would not be properly addressed by percutaneous SIJ fusion (SIJF) Imaging of the pelvis (anteroposterior (AP) plain radiograph) to rule out concomitant hip pathology Imaging of the lumbar spine (CT or MRI) to rule out neural compression or other degenerative condition that can be causing low back or buttock pain B . MI Arthrodesis of the SIJ WITHOUT placement of a transfixation device is NOT considered medically reasonable and necessary. Limitations: Absence of generalized pain behavior (e.g., somatoform disorder) or generalized pain disorders (e.g., fibromyalgia) Patient should be part of an ongoing care plan, and be actively participating in a rehabilitation program, home exercise program or functional restoration program