Comparison of the costs of nonoperative care to minimally invasive surgery for sacroiliac joint disruption and degenerative sacroiliitis in a United States commercial payer population: potential economic implications of a new minimally invasive technology

Cost-Utility Analysis of Sacroiliac Joint Fusion in High-Risk Patients Undergoing Multi-Level Lumbar Fusion to the Sacrum

Purpose

Multi-level lumbar fusion to the sacrum (MLF) can lead to increased stress and angular motion across the sacroiliac joint (SIJ), with an incidence of post-operative SIJ pain estimated at 26–32%. SIJ fusion (SIJF) can help obviate the need for revisions by reducing range of motion and screw stresses. We aimed to evaluate the cost-utility of MLF + SIJF compared to MLF alone among high-risk patients from a payer perspective, where high risk is defined as high body mass index and high pelvic incidence.

Methods

A Markov process decision-analysis model was developed to evaluate cumulative 5-year costs, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER) of MLF + SIJF compared to MLF alone using published data; costs from Medicare claims data analyses and health state utility values (derived from EQ-5D) informed by three prospective, multicenter, clinical trials. The base case assumed a reduction in post-operative SIJ pain from 30% to 10% (relative risk reduction [RRR] of 67%). Costs and utilities were discounted 3% annually. The ICER is reported in 2020 US dollars. One-way, multi-way, and probabilistic sensitivity analyses were performed.

Results

With an assumed 30% incidence of SIJ pain after MLF alone, stabilizing with SIJF was associated with an additional 5-year cost of $2421 and a gain of 0.14 QALYs, resulting in an ICER of $17,293 per QALY gained (similar to total knee arthroplasty and more favorable than open discectomy). ICERs were most sensitive to the RRR of post-operative SIJ pain conferred by SIJF, time horizon, and probability of successful treatment with MLF alone. At a willingness-to-pay threshold of $50,000/QALY gained, MLF + SIJF has a 97.7% probability of being cost-effective in the target patient population.

Conclusion

Fusing the SIJ in high-risk patients undergoing MLF was cost-effective when the incidence of post-operative SIJ pain after MLF alone exceeds approximately 25%, providing value-based healthcare from a payer perspective.

Three-Year Clinical Outcomes after Minimally Invasive Sacroiliac Joint Arthrodesis Using Triangular Implants in Japan: A Pilot Study of Five Cases

Introduction

Sacroiliac joint (SIJ) arthrodesis using a minimally invasive technique, particularly the triangular implant system, is performed in patients with SIJ dysfunction in the United States and Europe. We report three-year clinical outcomes of the first minimally invasive SIJ arthrodesis procedures using the implants performed in Japan.

Methods

Five patients (one man and four women; age: 56.4±16.9 years) with SIJ pain who underwent SIJ arthrodesis using a triangular implant system in 2017 were included. In addition to operation time and blood loss, pain intensity (visual analog scale [VAS]) and functional impairment (Oswestry disability index [ODI]) were assessed preoperatively and at a 36-month follow-up. Implant loosening and osseous bridging across the joint were evaluated using computed tomography images, and patients' satisfaction with the surgery was also assessed at 12 and 36 months.

Results

The surgical time was 67.7±13.1 minutes, and blood loss was 7.4±6.9 mL. The mean VAS value improved significantly from 88.0±8.4 mm to 33.6±31.9 mm at 3 months and was maintained at 46.4±30.9 mm at 36 months (P<0.05). The mean ODI improved significantly from 76.4%±3.8% to 46.2%±21.9% at 6 months postoperatively (P<0.05) but had no significant improvements thereafter: 46.94±23.7% (12 months) and 66.4±8.6% (36 months). Three of five patients presented with at least one implant loosening on the sacrum side. No patient had osseous bridging across the joint. A total of 80% (4/5) of patients reported satisfaction with the surgery at 12 months and 60% (3/5) at 36 months.

Conclusions

The mean VAS value and ODI significantly improved until 6 months after the surgery. However, the mean ODI was reaggravated at 36 months after the surgery. Osseous bridging across the joint was not observed in all patients. We should carefully keep an eye on further long-term results to evaluate the implant.

A Multicenter Retrospective Analysis of the Long-Term Efficacy and Safety of a Novel Posterior Sacroiliac Fusion Device

Background

Sacroiliac joint (SIJ) pathology is a cause of low back pain that may be difficult to diagnose and challenging to treat. Open and minimally invasive (MI) lateral approach fusions have been used to treat sacroiliitis over the past two decades. A novel MI posterior approach SIJ fusion technique utilizes a posteriorly placed transfixing device with single point S1/S2 level or mid-segment SIJ fixation (LinQ procedure). Current efficacy and safety data for this novel procedure are lacking.

Objective

To review multicenter retrospective 12 months or greater outcomes data in patients receiving the LinQ procedure, with sub-analysis of patients with prior lumbar fusions.

Methods

Patients with sacroiliitis refractory to conservative care with short-term benefit from diagnostic local anesthetic SIJ injections receiving MI posterior approach SIJ fusion with allograft were included from different centers including both academic and private practice. Numeric rating scale (NRS) scores at baseline (pre-procedural) and most recent follow-up were reviewed across three institutions.

Results

Of 110 patients who received MI SIJ fusion, 50 patients had sufficient data for evaluation of outcomes at least 12 months post-implant. The average time out from implant at follow-up was 612.2 days for all unique patients. The average NRS was 6.98 pre-fusion and 3.06 at last follow-up. Twenty-four patients had prior lumbar surgery of which 17 had prior lumbar fusions. Average NRS for this subset was 6.85 at baseline and 2.86 at last follow-up with an average follow-up of 613.2 days out from implant. No major adverse events or complications were associated with any of the 50 implants.

Conclusion

Real-world evidence suggests that MI posterior SIJ fusion with the LinQ procedure is a viable approach for medically refractory sacroiliitis management with long-term efficacy and safety. Further prospective studies are needed to fully evaluate this technique.

Impact of diagnosis and type of sacroiliac joint fusion on postoperative complications

PURPOSE

Two main surgical approaches are available for fusing the sacroiliac joint (SIJ): an open or minimally invasive (MIS) approach. The purpose of this study was to analyze the associated total hospital charges and postoperative complications of the MIS and open approach.

METHODS

Using the 2016 and 2017 National Readmission Database, we conducted a retrospective cohort analysis of 2521 patients who received a SIJ fusion with an open (N = 1990) or MIS (N = 531) approach for diagnosed sacrum pain, sacroiliitis, sacral instability, or spondylosis. Each cohort was analyzed for postoperative complications.

RESULTS

We identified 604 patients diagnosed with sacrum pain, 1142 with sacroiliitis, 315 with spondylosis, and 288 with sacral instability. Patients who received the open approach for sacrum pain had significantly higher rates of novel post-procedural pain (p = 0.045) and novel lumbar pathology (p = 0.015) within 30 days. On 30-day follow-up, patients with sacroiliitis treated with open SIJ fusion had significantly higher rates of novel postprocedural pain compared to those treated with MIS fusion (p = 0.045). Patients who received the open approach for spondylosis resulted in significantly higher rates of non-elective readmission within 30 days compared to the MIS approach (p < 0.0001). In addition, the open technique for spondylosis resulted in significantly higher rates of non-elective readmissions for infection within 30 days (p = 0.014). On 30-day follow-up, patients with sacral instability treated with open SIJ fusion had significantly higher rates of UTI (p = 0.045).

CONCLUSION

Our study suggests that there exist unique postoperative complications that arise after SIJ fusion specific to preoperative diagnosis and surgical approach.

Propensity-matched Analysis of 1062 Patients Following Minimally Invasive Versus Open Sacroiliac Joint Fusion

STUDY DESIGN

This was a retrospective cohort study.

OBJECTIVE

The aim of this study was to compare the hospital charges and postoperative complications of minimally invasive surgery (MIS) and open approaches to sacroiliac joint (SIJ) fusion.

SUMMARY OF BACKGROUND DATA

The data source utilized in this study is the Healthcare Cost and Utilization Project National Readmission Database (NRD) from 2016 and 2017. The NRD is a yearly nationally representative inpatient database from the Agency for Healthcare Research and Quality with information regarding patient demographics, diagnoses, procedures, and readmissions.

MATERIALS AND METHODS

The 2016-2017 NRD was used to identify 2521 patients receiving SIJ fusion with open (n=1990) or MIS approaches (n=531) for diagnosed sacrum pain, sacroiliitis, sacral instability, or spondylosis after excluding for those who received prior SIJ fusion, those diagnosed with neoplasms or trauma of the pelvis or sacrum, and nonelective procedures. We then one-to-one propensity-matched the open (n=531) to the MIS approach (n=531) for age, sex, and Charlson Comorbidity Index. Statistical analysis was performed to compare total hospital charges, immediate surgical complications, nonelective readmission rate, and 30-, 90-, and 180-day postoperative complications between the 2 approaches.

RESULTS

The mean total hospital charge was the only significant difference between 2 group. Open SIJ fusion had significantly higher charge compared with the MIS approach (open $101,061.90±$81,136.67; MIS $83,594.78±$49,086.00, P<0.0001). The open approach was associated with nonsignificant higher rates of novel lumbar pathology at 30-, 90-, and 180-day readmissions and revision surgeries at 30 and 180 days. MIS approach had higher rates nervous system complications at 30-, 90-, and 180-day readmission, as well as infection and urinary tract infection within 30 days, none being significant. Novel postprocedural pain was similar between the 2 groups at 90 and 180 days.

CONCLUSIONS

The current study found that open SIJ fusion was associated with significantly higher hospital charges. Although no significant differences in postoperative complications were found, there were several notable trends specific to each surgical approach.

Anatomical study of the innervation of different parts of the posterior ligamentous region of the sacroiliac joint

BACKGROUND AND OBJECTIVES

The periarticular sacroiliac joint (SIJ) technique has become an important area of focus, and the quartering of the SIJ posterior ligamentous region has been proposed as a way to refine this technique. However, detailed nerve distribution combined with the division of the SIJ posterior ligamentous region is lacking. We aimed to explore the innervation of the SIJ posteriorly based on the quartering of the SIJ posterior ligamentous region.

METHODS

Sixteen SIJs from eight embalmed cadavers were studied. Each SIJ posterior ligamentous region was equally divided into areas 0-3 from top to bottom. The origin, distribution, quantity, transverse diameter, spatial orientation, relation with bony structures, and the number of identifiable terminal nerve branches in each area were examined.

RESULTS

Areas 0-1 were innervated by the lateral branches of the dorsal rami of L4-L5 directly in all specimens. Areas 2-3 were innervated by that of both lumbar and sacral nerves via the posterior sacral network (PSN), with L5 contributing to the PSN in all specimens and L4 in 68.75%. The number of identifiable terminal nerve branches were significantly higher in areas 2-3 than in areas 0-1.

CONCLUSIONS

The inferior part of the SIJ posterior ligamentous region seems to be the main source of SIJ-related pain and is innervated by lumbar and sacral nerves via the PSN. However, the superior part directly innervated by lumbar nerves should not be neglected, and further clinical verification is needed.

International Society for the Advancement of Spine Surgery Policy 2020 Update-Minimally Invasive Surgical Sacroiliac Joint Fusion (for Chronic Sacroiliac Joint Pain): Coverage Indications, Limitations, and Medical Necessity

The index 2014 International Society for the Advancement of Spine Surgery Policy Statement-Minimally Invasive Surgical Sacroiliac Joint Fusion-was generated out of necessity to provide an International Classification of Diseases, Ninth Revision (ICD-9)-based background and emphasize tools to ensure correct diagnosis. A timely ICD-10-based 2016 update provided a granular threshold selection with improved level of evidence and a more robust and relevant database (Appendix Table A1). As procedures and treatment options have evolved, this 2020 update reviews and analyzes the expanding evidence base and provides guidance relating to differences between the lateral and dorsal surgical procedures for minimally invasive surgical sacroiliac joint fusion.

Health Care Resource Utilization and Management of Chronic, Refractory Low Back Pain in the United States

STUDY DESIGN:

Retrospective analysis of inpatient and outpatient medical insurance claims data from a database containing over 100 million individuals.

OBJECTIVE:

To quantify the healthcare resource utilization (HCRU) of non-surgical treatments in the first 2 years after a chronic, refractory low back pain (CRLBP) diagnosis.

SUMMARY OF BACKGROUND DATA:

Patients with persistent low back pain (LBP) despite conventional medical management and who are not candidates for spine surgery are considered to have chronic, refractory low back pain (CRLBP) and incur substantial healthcare costs over time. Few data exist on the HCRU of this specific population.

METHODS:

The IBM MarketScan Research databases from 2009 to 2016 were retrospectively analyzed to identify US adults with a diagnosis of non-specific LBP and without cancer, spine surgery, failed back surgery syndrome, or recent pregnancy. We required >30 days of utilization of pain medications or non-pharmacologic therapies within both the 3–12- and 12–24-month periods post-diagnosis. Annual total healthcare costs, costs subdivided by insurance type, and use of non-surgical therapies were determined for 2 years after diagnosis of LBP.

RESULTS:

55,945 patients with CRLBP were identified. Median total cost was $6,590 (Q1 $2,710, Q3 $13,922) in the first year, almost doubling the baseline cost; costs were highest for patients with Medicare Supplemental insurance, reaching $10,156 (Q1 $5,481, Q3 $18,570). 33,664 (60.2%) patients engaged physical therapy, 28,016 (50.1%) engaged chiropractors, and 14,488 (25.9%) had steroid injections. 36,729 (65.7%) patients used prescription pain medications, most commonly opioids (N=31,628, 56.5%) and muscle relaxants (N=21,267, 38.0%).

CONCLUSION:

This study is one of the first to investigate the HCRU of a large, longitudinal US cohort of patients with CRLBP. These patients experience substantial healthcare costs. Contrary to LBP management guidelines, most patients used opioids, and several non-pharmacologic therapies were used by only a few patients.

Minimally Invasive Sacroiliac Joint Fusion: The Current Evidence

Background

Fusion of the sacroiliac (SI) joint as a treatment for low back pain remains controversial. The purpose of this manuscript is to review the current literature and clinical outcomes of SI joint fusion surgery.

Methods

We conducted a literature review and included studies with the term "sacroiliac joint fusion" that had at least 12 months of clinical follow-up, reported on minimally invasive techniques, and included patient-reported outcome measures.

Results

Two approach types (dorsal and lateral) and numerous different implant manufacturers were identified. Most studies included level 4 data, with a small number of level 2 prospective cohort studies and 2 prospective level 1 studies. Every reviewed study reported clinical benefit in terms of improved pain scores or improvement in validated disability measures. Complication rates were low.

Conclusions

Minimally invasive SI joint fusion provides clinically significant improvement in pain scores and disability in most patients, across multiple studies and implant manufacturers.

Level of Evidence

5.

Clinical Relevance

Emerging evidence in support of SI joint fusion indicates that clinicians should examine the SI joint and include SI joint pain in their differential diagnosis for low back pain patients.

Economic Value in Minimally Invasive Spine Surgery

PURPOSE OF REVIEW

The field of spine surgery remains a unique target in the transition to value-based care. While spine surgery has benefited from new medical technologies, including minimally invasive surgery (MIS), these technologies may be a key driver in rising US healthcare costs. As such, MIS needs to clear an economic value threshold through a rigorous evaluation of the outcomes they provide and costs they incur. In this article, we review recent MIS surgery literature from the perspective of economic value.

RECENT FINDINGS

Many studies report modest all-in cost savings and direct procedural cost equivalence for minimally invasive approaches relative to open surgeries. In terms of quality, studies found lower blood loss, length of stay, and infectious complications with MIS surgery but evidence on QALYs was mixed. In the past 5 years, there has been increasing research interest in defining economic value in MIS surgery. However, a significant amount of heterogeneity in research quality and methodology persists. Therefore, MIS surgery has the potential to be of high economic value, though this is not yet definitive. Future research should continue to focus on high-quality cost-effectiveness studies with clear methodologies to further elucidate economic value in MIS surgery.

In Vitro Biomechanical Evaluation of a Novel, Minimally Invasive, Sacroiliac Joint Fixation Device

Background

Sacroiliac (SI) joint pathology may result in low-back pain, which causes substantial disability. Treatment failure with operative management of SI pain may be related to incomplete fusion of the joint and to fixation failure. The objective of this study was to evaluate the initial biomechanical stability of SI joint fixation with a novel implantable device in an in vitro human cadaveric model.

Methods

The right and left sides of 3 cadaveric L4-pelvis specimens were tested (1) intact, (2) destabilized, and (3) instrumented with an implantable SI joint fixation device using a simulated single-stance load condition. Right-leg and left-leg stance data were grouped together for a sample size of 6, and angular range of motion (ROM) was determined during application of flexion-extension, lateral bending, and axial rotation bending moments to a limit of 7.5 Nm.

Results

Following intact testing, destabilization by severing the posterior SI joint capsule and ligaments and the pubic symphysis reliably produced a significantly destabilized joint with the mean angular ROM more than doubling in flexion-extension and lateral bending and more than tripling in axial rotation (P ≤ .003) compared to the intact condition. Instrumentation with the SI screw fixation device significantly reduced mean joint ROM compared to the destabilized condition in all 3 anatomic planes tested (P < .001). When compared to the intact condition, the SI-instrumented condition significantly reduced lateral bending (P = .01) and had a similar ROM in flexion-extension (P = .14) and axial rotation (P = .85).

Conclusions

Instrumentation with the SI screw fixation device significantly reduced mean joint ROM compared to the destabilized condition, with similar ROM in flexion-extension and axial rotation, and it significantly reduced ROM in lateral bending compared to that for the intact joint. The ROM values observed with the instrumented condition were comparable to levels of mobility considered favorable for spinal fusion.

Management of Sacroiliac Joint Pain

Sacroiliac joint (SIJ)-based pain can be difficult to diagnose definitively through physical examination and conventional radiography. A fluoroscopically guided injection into the SIJ can be both diagnostic and therapeutic. The initial phase of treatment involves nonsurgical modalities such as activity modification, use of a sacroiliac (SI) belt, NSAIDs, and physical therapy. Prolotherapy and radiofrequency ablation may offer a potential benefit as therapeutic modalities, although limited data support their use as a primary treatment modality. Surgical treatment is indicated for patients with a positive response to an SI injection with >75% relief, failure of nonsurgical treatment, and continued or recurrent SIJ pain. Percutaneous SI arthrodesis may be recommended as a first-line surgical treatment because of its improved safety profile compared with open arthrodesis; however, in the case of revision surgery, nonunion, and aberrant anatomy, open arthrodesis should be performed.

Emerging Techniques in Degenerative Thoracolumbar Surgery

There continue to be incremental advances in thoracolumbar spine surgery techniques in attempts to achieve more predictable outcomes, minimize risk of complications, speed recovery, and minimize the costs of these interventions. This paper reviews recent literature with regard to emerging techniques of interest in the surgical treatment of lumbar spinal stenosis, fusion fixation and graft material, degenerative lumbar spondylolisthesis, and thoracolumbar deformity and sacroiliac joint degeneration. There continue to be advances in minimal access options in these areas, although robust outcome data are heterogeneous in its support. The evidence in support of sacroiliac fusion appears to be growing more robust in the properly selected patient.

Geographic Variation in Diagnostic Ability and Quality of Care Metrics: A Case Study of Ankylosing Spondylitis and Low Back Pain

Studies examining geographic variation in care for low back pain often focus on process and outcome measures conditional on patient diagnosis but generally do not take into account a physician's ability to diagnose the root cause of low back pain. In our case study, we used increased detection of ankylosing spondylitis-a relatively rare inflammatory back disease-as a proxy for diagnostic ability and measured the relationship between ankylosing spondylitis detection, potentially inappropriate low back pain care, and cost. Using 5 years of health insurance claims data, we found significant variation in ankylosing spondylitis detection across metropolitan statistical areas (MSAs), with 8.1% of the variation in detection explained by a region's racial composition. Furthermore, low back pain patients in MSAs with higher ankylosing spondylitis detection had 7.9% lower use of corticosteroids, 9.0% lower use of opioids, and 8.2% lower pharmacy cost, compared with patients living in low-detection MSAs.

Sacroiliac Joint Fusion: One Year Clinical and Radiographic Results Following Minimally Invasive Sacroiliac Joint Fusion Surgery

BACKGROUND

Recalcitrant sacroiliac joint pain responds well to minimally-invasive surgical (MIS) techniques, although long-term radiographic and fusion data are limited.

OBJECTIVE

To evaluate the one-year clinical results from a cohort of patients with chronic sacroiliac (SI) joint pain unresponsive to conservative therapies who have undergone minimally invasive SI joint fusion.

METHODS

SI joint fusion was performed between May 2011 and January 2014. Outcomes included radiographic assessment of fusion status, leg and back pain severity via visual analog scale (VAS), disability via Oswestry Disability Index (ODI) and complication rate. Outcomes were measured at baseline and at follow-up appointments 6 months and 12 months post-procedure.

RESULTS

Twenty minimally invasive SI joint fusion procedures were performed on 18 patients (mean age: 47.2 (14.2), mean BMI: 29.4 (5.3), 56% female). At 12 months, the overall fusion rate was 88%. Back and leg pain improved from 81.7 to 44.1 points (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). Despite a cohort containing patients with multiple comorbidities and work-related injuries, eight patients (50%) achieved the minimal clinically important difference (MCID) in back pain at 12 months, with 9 (69%) patients realizing this improvement in leg pain and 8 (57%) realizing the MCID in ODI scores at 12 months. No major complications were reported.

CONCLUSION

Minimally invasive SI joint surgery is a safe and effective procedure, with a high fusion rate, a satisfactory safety profile and significant improvements in pain severity and disability reported through 12 months post-procedure.

Cost-effectiveness of minimally invasive sacroiliac joint fusion

BACKGROUND

Sacroiliac joint (SIJ) disorders are common in patients with chronic lower back pain. Minimally invasive surgical options have been shown to be effective for the treatment of chronic SIJ dysfunction.

OBJECTIVE

To determine the cost-effectiveness of minimally invasive SIJ fusion.

METHODS

Data from two prospective, multicenter, clinical trials were used to inform a Markov process cost-utility model to evaluate cumulative 5-year health quality and costs after minimally invasive SIJ fusion using triangular titanium implants or non-surgical treatment. The analysis was performed from a third-party perspective. The model specifically incorporated variation in resource utilization observed in the randomized trial. Multiple one-way and probabilistic sensitivity analyses were performed.

RESULTS

SIJ fusion was associated with a gain of approximately 0.74 quality-adjusted life years (QALYs) at a cost of US$13,313 per QALY gained. In multiple one-way sensitivity analyses all scenarios resulted in an incremental cost-effectiveness ratio (ICER) <$26,000/QALY. Probabilistic analyses showed a high degree of certainty that the maximum ICER for SIJ fusion was less than commonly selected thresholds for acceptability (mean ICER =$13,687, 95% confidence interval $5,162-$28,085). SIJ fusion provided potential cost savings per QALY gained compared to non-surgical treatment after a treatment horizon of greater than 13 years.

CONCLUSION

Compared to traditional non-surgical treatments, SIJ fusion is a cost-effective, and, in the long term, cost-saving strategy for the treatment of SIJ dysfunction due to degenerative sacroiliitis or SIJ disruption.