Cost-effectiveness of minimally invasive midline lumbar interbody fusion versus traditional open transforaminal lumbar interbody fusion

Cost-utility of lumbar interbody fusion surgery: A systematic review

BACKGROUND CONTEXT

Lumbar interbody fusion (LIF) is a common surgical intervention for treating lumbar degenerative disorders. Increasing demand has contributed to ever-increasing healthcare expenditure and economic burden. To address this, cost-utility analyses (CUAs) compare value in the context of patient outcomes. CUAs quantify health improvements using quality-adjusted life years (QALYs), allowing decision-makers to determine procedure value.

PURPOSE

While there is a growing body of literature assessing LIF value, a comprehensive synthesis of LIF CUAs is lacking. This systematic review aims to address this gap by assessing all available CUAs of LIF techniques, to support evidence-based practices that improve outcomes and promote efficient resource use.

STUDY DESIGN

Systematic review.

STUDY SAMPLE

This study sample consisted of adult patients with lumbar degenerative conditions specifically treated with lumbar interbody fusion, including grade I or II degenerative spondylolisthesis, lumbar spinal stenosis, disc degeneration, and spondylosis, with or without low back and/or leg pain.

OUTCOME MEASURES

Direct (healthcare) and indirect (non-healthcare) costs, cost sources and calculation methods, utility scores, QALY gain, cost-utility, incremental cost-effectiveness ratios, and willingness-to-pay thresholds. Outcomes were reported as median and interquartile ranges (IQR).

METHODS

A systematic review was conducted following PRISMA guidelines. PubMed, Web of Science, and Embase were searched from inception to October 23, 2023, for CUAs reporting QALYs and costs of LIF procedures. Relevant studies were selected and data extracted. Subgroup analyses compared minimally invasive versus open surgery and anterior versus posterior approaches. Study quality was assessed using the CHEC-Extended tool. Quantitative meta-analysis was not performed due to methodological heterogeneity.

RESULTS

Out of 2047 identified studies, 14 met inclusion criteria. The mean CHEC-Extended score was 72.1%. Most studies reported on TLIF (n=11) and utilized EQ-5D questionnaire to calculate utility (n=9). Direct costs were sourced from institutional databases, Medicare, DRGs, Redbook, and a variety of other sources. Most indirect costs were estimated from productivity loss. TLIF demonstrated the highest median QALY gain over 1 year (0.43, IQR 0.121-0.705), while PLIF was highest over 2 years (1.33). ALIF was most favorable over 1 year ($30901/QALY) and OLIF was most favorable over 2 years ($11187/QALY). PLIF, TLIF, and LLIF exhibited similar cost-utility over 2 years ($44383, $45628, $48576/QALY). MIS was substantially favorable to OS at 1 year ($42635 vs. $226304), though similar at 2 years ($48576 vs. $45628/QALY). Anterior approach was favorable to posterior approach at 1 year ($30901.5 vs. $81038) and 2 years ($29881.9 vs. $44383). Cost-utility comparisons substantially varied and were sensitive to utility measures, study methodology, cost sourcing, and follow-up duration.

CONCLUSIONS

This is the first systematic review to comprehensively assess CUAs of all LIF approaches in the existing literature. While certain approaches, such as ALIF and OLIF, may demonstrate favorable outcomes, these conclusions are limited by high methodological heterogeneity and a limited study pool. By addressing existing gaps in study design and reporting, future comparative cost-utility research can better inform evidence-based decision-making and optimize the value of spinal surgical care.

Thoracolumbar fusions for adult lumbar deformity show superior QALY gain and lower costs compared with upper thoracic fusions

PURPOSE

Adult spinal deformity (ASD) patients with sagittal plane deformity (N) or structural lumbar/thoraco-lumbar (TL) curves can be treated with fusions stopping at the TL junction or extending to the upper thoracic (UT) spine. This study evaluates the impact on cost/cumulative quality-adjusted life year (QALY) in patients treated with TL vs UT fusion.

METHODS

ASD patients with > 4-level fusion and 2-year follow-up were included. Index and total episode-of-care costs were estimated using average itemized direct costs obtained from hospital records. Cumulative QALY gained were calculated from preoperative to 2-year postoperative change in Short Form Six-Dimension (SF-6D) scores. The TL and UT groups comprised patients with upper instrumented vertebrae (UIV) at T9-T12 and T2-T5, respectively.

RESULTS

Of 566 patients with type N or L curves, mean age was 63.2 ± 12.1 years, 72% were female and 93% Caucasians. Patients in the TL group had better sagittal vertical axis (7.3 ± 6.9 vs. 9.2 ± 8.1 cm, p = 0.01), lower surgical invasiveness (- 30; p < 0.001), and shorter OR time (- 35 min; p = 0.01). Index and total costs were 20% lower in the TL than in the UT group (p < 0.001). Cost/QALY was 65% lower (492,174.6 vs. 963,391.4), and 2-year QALY gain was 40% higher, in the TL than UT group (0.15 vs. 0.10; p = 0.02). Multivariate model showed TL fusions had lower total cost (p = 0.001) and higher QALY gain (p = 0.03) than UT fusions.

CONCLUSION

In Schwab type N or L curves, TL fusions showed lower 2-year cost and improved QALY gain without increased reoperation rates or length of stay than UT fusions.

LEVEL OF EVIDENCE

III.

The Implementation of Enhanced Recovery After Spine Surgery in High and Low/Middle-income Countries: A Systematic Review and Meta-Analysis

In this review article, we explore the implementation and outcomes of enhanced recovery after spine surgery (spine ERAS) across different World Bank country-income levels. A systematic literature search was conducted through PubMed, Embase, Scopus, and CINAHL databases for articles on the implementation of spine ERAS in both adult and pediatric populations. Study characteristics, ERAS elements, and outcomes were analyzed and meta-analyses were performed for length of stay (LOS) and cost outcomes. The number of spine ERAS studies from low-middle-income countries (LMICs) increased since 2017, when the first spine ERAS implementation study was published. LMICs were more likely than high-income countries (HICs) to conduct studies on patients aged ≥18 years (odds ratio [OR], 6.00; 95% CI, 1.58-42.80), with sample sizes 51 to 100 (OR, 4.50; 95% CI, 1.21-22.90), and randomized controlled trials (OR, 7.25; 95% CI, 1.77-53.50). Preoperative optimization was more frequently implemented in LMICs than in HICs (OR, 2.14; 95% CI, 1.06-4.41), and operation time was more often studied in LMICs (OR 3.78; 95% CI, 1.77-8.35). Implementation of spine ERAS resulted in reductions in LOS in both LMIC (-2.06; 95% CI, -2.47 to -1.64 d) and HIC (-0.99; 95% CI, -1.28 to -0.70 d) hospitals. However, spine ERAS implementation did result in a significant reduction in costs. This review highlights the global landscape of ERAS implementation in spine surgery, demonstrating its effectiveness in reducing LOS across diverse settings. Further research with standardized reporting of ERAS elements and outcomes is warranted to explore the impact of spine ERAS on cost-effectiveness and other patient-centered outcomes.

Location variance of the great vessels while undergoing side-bend positioning changes during lateral interbody fusion

Background

Minimally invasive lateral lumbar interbody fusion (LLIF) is an increasingly popular surgical technique that facilitates minimally invasive exposure, attenuated blood loss, and potentially improved arthrodesis rates. However, there is a paucity of evidence elucidating the risk of vascular injury associated with LLIF, and no previous studies have evaluated the distance from the lumbar intervertebral space (IVS) to the abdominal vascular structures in a side-bend lateral decubitus position. Therefore, the purpose of this study is to evaluate the average distance, and changes in distance, from the lumbar IVS to the major vessels from supine to side-bend right and left lateral decubitus (RLD and LLD) positions simulating operating room positioning utilizing magnetic resonance imaging (MRI).

Methods

We independently evaluated lumbar MRI scans of 10 adult patients in the supine, RLD, and LLD positions, calculating the distance from each lumbar IVS to adjacent major vascular structures.

Results

At the cephalad lumbar levels (L1-L3), the aorta lies in closer proximity to the IVS in the RLD position, in contrast to the inferior vena cava (IVC), which is further from the IVS in the RLD. At the L3-S1 vertebral levels, the right and left common iliac arteries (CIA) are both further from the IVS in the LLD position, with the notable exception of the right CIA, which lies further from the IVS in the RLD at the L5-S1 level. At both the L4-5 and L5-S1 levels, the right common iliac vein (CIV) is further from the IVS in the RLD. In contrast, the left CIV is further from the IVS at the L4-5 and L5-S1 levels.

Conclusion

Our results suggest that RLD positioning may be safer for LLIF as it affords greater distance away from critical venous structures, however, surgical positioning should be assessed at the discretion of the spine surgeon on a patient-specific basis.

A Proposed Personalized Spine Care Protocol (SpineScreen) to Treat Visualized Pain Generators: An Illustrative Study Comparing Clinical Outcomes and Postoperative Reoperations between Targeted Endoscopic Lumbar Decompression Surgery, Minimally Invasive TLIF and Open Laminectomy

Background: Endoscopically visualized spine surgery has become an essential tool that aids in identifying and treating anatomical spine pathologies that are not well demonstrated by traditional advanced imaging, including MRI. These pathologies may be visualized during endoscopic lumbar decompression (ELD) and categorized into primary pain generators (PPG). Identifying these PPGs provides crucial information for a successful outcome with ELD and forms the basis for our proposed personalized spine care protocol (SpineScreen). Methods: a prospective study of 412 patients from 7 endoscopic practices consisting of 207 (50.2%) males and 205 (49.8%) females with an average age of 63.67 years and an average follow-up of 69.27 months was performed to compare the durability of targeted ELD based on validated primary pain generators versus image-based open lumbar laminectomy, and minimally invasive lumbar transforaminal interbody fusion (TLIF) using Kaplan-Meier median survival calculations. The serial time was determined as the interval between index surgery and when patients were censored for additional interventional and surgical treatments for low back-related symptoms. A control group was recruited from patients referred for a surgical consultation but declined interventional and surgical treatment and continued on medical care. Control group patients were censored when they crossed over into any surgical or interventional treatment group. Results: of the 412 study patients, 206 underwent ELD (50.0%), 61 laminectomy (14.8%), and 78 (18.9%) TLIF. There were 67 patients in the control group (16.3% of 412 patients). The most common surgical levels were L4/5 (41.3%), L5/S1 (25.0%), and L4-S1 (16.3%). At two-year f/u, excellent and good Macnab outcomes were reported by 346 of the 412 study patients (84.0%). The VAS leg pain score reduction was 4.250 ± 1.691 (p < 0.001). No other treatment during the available follow-up was required in 60.7% (125/206) of the ELD, 39.9% (31/78) of the TLIF, and 19.7% (12/61 of the laminectomy patients. In control patients, only 15 of the 67 (22.4%) control patients continued with conservative care until final follow-up, all of which had fair and poor functional Macnab outcomes. In patients with Excellent Macnab outcomes, the median durability was 62 months in ELD, 43 in TLIF, and 31 months in laminectomy patients (p < 0.001). The overall survival time in control patients was eight months with a standard error of 0.942, a lower boundary of 6.154, and an upper boundary of 9.846 months. In patients with excellent Macnab outcomes, the median durability was 62 months in ELD, 43 in TLIF, and 31 months in laminectomy patients versus control patients at seven months (p < 0.001). The most common new-onset symptom for censoring was dysesthesia ELD (9.4%; 20/206), axial back pain in TLIF (25.6%;20/78), and recurrent pain in laminectomy (65.6%; 40/61) patients (p < 0.001). Transforaminal epidural steroid injections were tried in 11.7% (24/206) of ELD, 23.1% (18/78) of TLIF, and 36.1% (22/61) of the laminectomy patients. The secondary fusion rate among ELD patients was 8.8% (18/206). Among TLIF patients, the most common additional treatments were revision fusion (19.2%; 15/78) and multilevel rhizotomy (10.3%; 8/78). Common follow-up procedures in laminectomy patients included revision laminectomy (16.4%; 10/61), revision ELD (11.5%; 7/61), and multilevel rhizotomy (11.5%; 7/61). Control patients crossed over into ELD (13.4%), TLIF (13.4%), laminectomy (10.4%) and interventional treatment (40.3%) arms at high rates. Most control patients treated with spinal injections (55.5%) had excellent and good functional outcomes versus 40.7% with fair and poor (3.7%), respectively. The control patients (93.3%) who remained in medical management without surgery or interventional care (14/67) had the worst functional outcomes and were rated as fair and poor. Conclusions: clinical outcomes were more favorable with lumbar surgeries than with non-surgical control groups. Of the control patients, the crossover rate into interventional and surgical care was 40.3% and 37.2%, respectively. There are longer symptom-free intervals after targeted ELD than with TLIF or laminectomy. Additional intervention and surgical treatments are more often needed to manage new-onset postoperative symptoms in TLIF- and laminectomy compared to ELD patients. Few ELD patients will require fusion in the future. Considering the rising cost of surgical spine care, we offer SpineScreen as a simplified and less costly alternative to traditional image-based care models by focusing on primary pain generators rather than image-based criteria derived from the preoperative lumbar MRI scan.

Comparison of Perioperative and Postoperative Outcomes of Minimally Invasive and Open TLIF in Obese Patients: A Systematic Review and Meta‑Analysis

PURPOSE

Previous studies have demonstrated that minimally invasive (MI) transforaminal lumbar interbody fusion (TLIF) is comparable to the open approach in terms of efficacy and safety. However, few comparative studies of surgical procedures in patients with obesity show that they may react differently to open-TLIF (O-TLIF) and MI-LTIF approaches.

PATIENTS AND METHODS

The main indicators were complications, visual analog scale (VAS) score, and Oswestry Disability Index (ODI) score, and secondary indicators were operative time, blood loss, and hospital stay.

RESULTS

No significant differences in the VAS and ODI scores for back pain at the last follow-up and wound infection rates were observed between the two groups. Dural tear incidence and complication rate were significantly lower in the MI-TLIF group than that in the O-TLIF group (P = 0.002 and 0.001, respectively). No significant difference in operative time was found between the two groups. There was less blood loss and shorter hospital stay (P = 0.001 and 0.002, respectively) in the MI-TLIF group than that in the O-TLIF group.

CONCLUSION

Compared with O-TLIF, MI-TLIF is an effective and safe surgical option for patients with obesity, which resulted in similar improvements in pain and functional disability, as well as a lower complication rate.

Comparison of (Partial) economic evaluations of transforaminal lumbar interbody fusion (TLIF) versus Posterior lumbar interbody fusion (PLIF) in adults with lumbar spondylolisthesis: A systematic review

Introduction

The demand for spinal fusion surgery has increased over the last decades. Health care providers should take costs and cost-effectiveness of these surgeries into account. Open transforaminal lumbar interbody fusion (TLIF) and posterior lumbar interbody fusion (PLIF) are two widely used techniques for spinal fusion. Earlier research revealed that TLIF is associated with less blood loss, shorter surgical time and sometimes shorter length of hospital stay, while effectiveness of both techniques on back and/or leg pain are equal. Therefore, TLIF could result in lower costs and be more cost-effective than PLIF. This is the first systematic review comparing direct and indirect (partial) economic evaluations of TLIF with PLIF in adults with lumbar spondylolisthesis. Furthermore, methodological quality of included studies was assessed.

Methods

Searches were conducted in eight databases for reporting on eligibility criteria; TLIF or PLIF, lumbar spondylolisthesis or lumbar instability, and cost. Costs were converted to United States Dollars with reference year 2020. Study quality was assessed using the bias assessment tool of the Cochrane Handbook for Systematic Reviews of Interventions, the Level of Evidence guidelines of the Oxford Centre for Evidence-based Medicine and the Consensus Health Economic Criteria (CHEC) list.

Results

Of a total of 693 studies, 16 studies were included. Comparison of TLIF and PLIF could only be made indirectly, since no study compared TLIF and PLIF directly. There was a large heterogeneity in health care and societal perspective costs due to different in-, and exclusion criteria, baseline characteristics and the use of costs or charges in calculations. Health care perspective costs, calculated with hospital costs, ranged from $15,867-$43,217 in TLIF-studies and $32,662 in one PLIF-study. Calculated with hospital charges, it ranged from $8,964-$51,469 in TLIF-studies and $21,838-$93,609 in two PLIF-studies. Societal perspective costs and cost-effectiveness, only mentioned in TLIF-studies, ranged from $5,702/QALY-$48,538/QALY and $50,092/QALY-$90,977/QALY, respectively. Overall quality of studies was low.

Conclusions

This systematic review shows that TLIF and PLIF are expensive techniques. Moreover, firm conclusions about the preferable technique, based on (partial) economic evaluations, cannot be drawn due to limited studies and heterogeneity. Randomized prospective trials and full economical evaluations with direct TLIF and PLIF comparison are needed to obtain high levels of evidence. Furthermore, development of guidelines to perform adequate economic evaluations, specified for the field of interest, will be useful to minimize heterogeneity and maximize transferability of results.

Trial registration

Prospero-database registration number: CRD42020196869.