Minimally invasive versus open transforaminal lumbar interbody fusion for degenerative spondylolisthesis: comparative effectiveness and cost-utility analysis

Is Less Really More? Economic Evaluation of Minimally Invasive Surgery

STUDY DESIGN

Review.

OBJECTIVE

A comparative overview of cost-effectiveness between minimally invasive versus and equivalent open spinal surgeries.

METHODS

A literature search using PubMed was performed to identify articles of interest. To maximize the capture of studies in our initial search, we combined variants of the terms "cost," "minimally invasive," "spine," "spinal fusion," "decompression" as either keywords or MeSH terms. PearlDiver database was queried for open and minimally invasive surgery (MIS; endoscopic or percutaneous) reimbursements between Q3 2015 and Q2 2018.

RESULTS

In general, MIS techniques appeared to decrease blood loss, shorten hospital lengths of stay, mitigate complications, decrease perioperative pain, and enable quicker return to daily activities when compared to equivalent open surgical techniques. With regard to cost, primarily as a result of these latter benefits, MIS was associated with lower costs of care when compared to equivalent open techniques. However, cost reporting was sparse, and relevant methodology was inconsistent throughout the spine literature. Within the PearlDiver data sets, MIS approaches had lower reimbursements than open approaches for both lumbar posterior fusion and discectomy.

CONCLUSIONS

Current data suggests that overall cost-savings may be incurred with use of MIS techniques. However, data reporting on costs lacks in uniformity, making it difficult to formulate any firm conclusions regarding any incremental improvements in cost-effectiveness that may be incurred when utilizing MIS techniques when compared to equivalent open techniques.

Percutaneous Peripheral Nerve Stimulation of the Medial Branch Nerves for the Treatment of Chronic Axial Back Pain in Patients After Radiofrequency Ablation

OBJECTIVE

Lumbar radiofrequency ablation is a commonly used intervention for chronic back pain. However, the pain typically returns, and though retreatment may be successful, the procedure involves destruction of the medial branch nerves, which denervates the multifidus. Repeated procedures typically have diminishing returns, which can lead to opioid use, surgery, or implantation of permanent neuromodulation systems. The objective of this report is to demonstrate the potential use of percutaneous peripheral nerve stimulation (PNS) as a minimally invasive, nondestructive, motor-sparing alternative to repeat radiofrequency ablation and more invasive surgical procedures.

DESIGN

Prospective, multicenter trial.

METHODS

Individuals with a return of chronic axial pain after radiofrequency ablation underwent implantation of percutaneous PNS leads targeting the medial branch nerves. Stimulation was delivered for up to 60 days, after which the leads were removed. Participants were followed up to 5 months after the start of PNS. Outcomes included pain intensity, disability, and pain interference.

RESULTS

Highly clinically significant (≥50%) reductions in average pain intensity were reported by a majority of participants (67%, n = 10/15) after 2 months with PNS, and a majority experienced clinically significant improvements in functional outcomes, as measured by disability (87%, n = 13/15) and pain interference (80%, n = 12/15). Five months after PNS, 93% (n = 14/15) reported clinically meaningful improvement in one or more outcome measures, and a majority experienced clinically meaningful improvements in all three outcomes (i.e., pain intensity, disability, and pain interference).

CONCLUSIONS

Percutaneous PNS has the potential to shift the pain management paradigm by providing an effective, nondestructive, motor-sparing neuromodulation treatment.

Minimally invasive tubular laminectomies in multilevel spine surgery-an illustrative case-based review of techniques and combined approaches

Minimally invasive techniques have become part of the spine surgeons' armamentarium and are currently utilized to treat many conditions involving the cervical, thoracic, lumbar and sacral spine. Surgical treatment of severe degenerative conditions such as multilevel spinal stenosis, tandem stenosis, combination of stenosis or disk herniation and spondylolisthesis at adjacent spinal levels, as well as extensive infections or hematomas, may require a multilevel tailored approach with all the challenges that such surgical planning entails. Although the use of minimally invasive tubular decompressive procedures has gained widespread popularity in the recent years, the adoption of such techniques during multilevel spine surgery can be at times challenging. A careful tailored selection of the surgical approach that better fits needs and expectations of the patient is therefore consequential to achieve good clinical and radiological outcome without compromising efficiency and results. Many surgical techniques have been described in literature but very few reports on the use of combined tubular approached are currently present. We therefore present an illustrative review of techniques for tubular laminectomies and combined approaches that can be utilized in the surgical treatment of multilevel spinal conditions. Illustrative cases documenting common and less common indications for the use of minimally invasive laminectomies are also presented.

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.

A cost benefit analysis of increasing surgical technology in lumbar spine fusion

BACKGROUND CONTEXT

Numerous advances have been made in the field of spine fusion, such as minimally invasive (MIS) or robotic-assisted spine surgery. However, it is unknown how these advances have impacted the cost of care.

PURPOSE

Compare the economic outcomes of lumbar spine fusion between open, MIS, and robot-assisted surgery patients.

STUDY DESIGN/SETTING

Retrospective review of a single center spine surgery database.

PATIENT SAMPLE

Three hundred sixty propensity matched patients.

OUTCOME MEASURES

Costs, EuroQol-5D (EQ5D), cost per quality adjusted life years (QALY).

METHODS

Inclusion criteria: surgical patients >18 years undergoing lumbar fusion surgery. Patients were categorized into 3 groups based on procedure type: open, MIS, or robotic. Open patients undergoing poster spinal fusion were considered as the control group. MIS patients included those undergoing transforaminal or lateral lumbar interbody fusion with percutaneous screws. Robotic patients were those undergoing robot-assisted fusion. Propensity score matching was performed between all groups for the number of levels fused. Costs were calculated using the PearlDiver database, which reflects both private insurance and Medicare reimbursement claims for ICD-9 codes. For robotic cases, costs were reflective of operational fees and initial purchase cost. Complications and comorbidities and major complications and comorbidities were assessed according to CMS.gov manual definitions. QALYs and cost per QALY were calculated using a 3% discount rate to account for residual decline to life expectancy (78.7 years). Costs per QALY were calculated for both 1 year and life expectancy, assuming no loss of benefit. A 10,000 trial Monte Carlo simulation with probabilistic sensitivity analysis (PSA) assessed our model parameters and costs.

RESULTS

Three hundred sixty propensity matched patients (120 open, 120 MIS, 120 robotic) met inclusion criteria. Descriptive statistics for the cohort were: age 58.8±13.5, 50% women, BMI 29.4±6.3, operative time 294.4±119.0, LOS 4.56±3.31 days, estimated blood loss 515.9±670.0 cc, and 2.3±2.2 average levels fused. Rates of post-op complications were significantly higher in robotic cases versus open and MIS (43% vs. 21% and 22% for open and MIS, p<.05). However, revision rates were comparable between all groups (3% open, 3% MIS, 5% robotic, p>.05). After factoring in complications, revisions, and purchasing and operating fees, the costs of robotic cases was significantly higher than both open and MIS surgery ($60,047.01 vs. $42,538.98 open and $41,471.21 MIS). In a subanalysis of 42 patients with baseline (BL) and 1Y EQ5D data, the cost per QALY at 1Y for open, MIS, and robot-assisted cases was $296,624.48, $115,911.69, and $592,734.30. If utility gained was sustained to life expectancy, the cost per QALY was $14,905.75, $5,824.71, $29,785.64 for open, MIS, and robot-assisted cases. Results of the PSA were consistent with MIS surgery having the most incremental cost effectiveness when compared to open and robotic surgery.

CONCLUSIONS

Numerous advances have been made in the field of spine surgery, however, there has been limited discussion of the effect these advances have on economic outcomes. When matched for levels fused, robot-assisted surgery patients had significantly higher rates of complications and 30% higher costs of surgery compared to minimally invasive and open spine surgery patients. While 1 year economic outcomes were not optimal for robotic surgery cases, the projected costs per QALYs at life expectancy were well below established acceptable thresholds. The above findings may be reflective of an educational learning curve and emerging surgical technologies undergoing progressive refinement.

A Comparison of Minimally Invasive and Open Transforaminal Lumbar Interbody Fusion for Grade 1 Degenerative Lumbar Spondylolisthesis: An Analysis of the Prospective Quality Outcomes Database

BACKGROUND

It remains unclear if minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) is comparable to traditional, open TLIF because of the limitations of the prior small-sample-size, single-center studies reporting comparative effectiveness.

OBJECTIVE

To compare MI-TLIF to traditional, open TLIF for grade 1 degenerative lumbar spondylolisthesis in the largest study to date by sample size.

METHODS

We utilized the prospective Quality Outcomes Database registry and queried patients with grade 1 degenerative lumbar spondylolisthesis who underwent single-segment surgery with MI- or open TLIF methods. Outcomes were compared 24 mo postoperatively.

RESULTS

A total of 297 patients were included: 72 (24.2%) MI-TLIF and 225 (75.8%) open TLIF. MI-TLIF surgeries had lower mean body mass indexes (29.5 ± 5.1 vs 31.3 ± 7.0, P = .0497) and more worker's compensation cases (11.1% vs 1.3%, P < .001) but were otherwise similar. MI-TLIF had less blood loss (108.8 ± 85.6 vs 299.6 ± 242.2 mL, P < .001), longer operations (228.2 ± 111.5 vs 189.6 ± 66.5 min, P < .001), and a higher return-to-work (RTW) rate (100% vs 80%, P = .02). Both cohorts improved significantly from baseline for 24-mo Oswestry Disability Index (ODI), Numeric Rating Scale back pain (NRS-BP), NRS leg pain (NRS-LP), and Euro-Qol-5 dimension (EQ-5D) (P > .001). In multivariable adjusted analyses, MI-TLIF was associated with lower ODI (β = -4.7; 95% CI = -9.3 to -0.04; P = .048), higher EQ-5D (β = 0.06; 95% CI = 0.01-0.11; P = .02), and higher satisfaction (odds ratio for North American Spine Society [NASS] 1/2 = 3.9; 95% CI = 1.4-14.3; P = .02). Though trends favoring MI-TLIF were evident for NRS-BP (P = .06), NRS-LP (P = .07), and reoperation rate (P = .13), these results did not reach statistical significance.

CONCLUSION

For single-level grade 1 degenerative lumbar spondylolisthesis, MI-TLIF was associated with less disability, higher quality of life, and higher patient satisfaction compared with traditional, open TLIF. MI-TLIF was associated with higher rates of RTW, less blood loss, but longer operative times. Though we utilized multivariable adjusted analyses, these findings may be susceptible to selection bias.

Clinical study on minimally invasive transforaminal lumbar interbody fusion surgery for lumbar spondylolisthesis combined with severe narrowing of the intervertebral space

Objective

To investigate the different clinical characteristics of minimally invasive transforaminal lumbar interbody fusion on treatment of lumbar spondylolisthesis combined with severe narrowing of the intervertebral space or simple grade II lumbar spondylolisthesis.

Methods

Thirty-eight patients were divided into groups A (16 cases combined with severe intervertebral space narrowing) or B (22 cases of simple grade II lumbar spondylolisthesis without intervertebral space narrowing). Differences in preoperative preparation, operation time, blood loss, tool selection, decompression, reduction, pedicle screw, cage size selection, and other aspects were compared. The Visual Analogue Scale (VAS) and Japanese Orthopaedic Association (JOA) scores were used to assess the effect of treatment.

Results

The operation time was significantly longer, blood loss was greater, the anatomical reduction rate was lower, and cage size was smaller in group A than in group B. Furthermore, special tools were required for treating the lumbar intervertebral space and the pedicle screws were different between the groups. JOA and VAS scores were similar between the groups

Conclusions

Cases of severe intervertebral space narrowing need to be fully released, with bilateral decompression, and special intervertebral processing tools need to be prepared. Long pedicle screws are conducive to connecting the rod and reducing slippage.

Minimally invasive versus traditional open transforaminal lumbar interbody fusion for the treatment of low-grade degenerative spondylolisthesis: a retrospective study

This was a retrospective study. We aimed to compare the clinical efficacy and safety between minimally invasive and traditional open transforaminal lumbar interbody fusion in the treatment of low-grade lumbar degenerative spondylolisthesis (LDS). 81 patients with LDS grades 1 and 2 treated in our spinal department from January 2014 to July 2016 were retrospectively analyzed. The MIS-TLIF group included 23 males and 11 females, while the TO-TLIF group included 29 males and 18 females. Follow-up points were set at 7 days, 3 months, 6 months, 12 months postoperatively and the last follow-up. Various clinical and radiological indicators were used to evaluate and compare the efficacy and safety between the two procedures. 8 cases (3 in the MIS-TLIF group and 5 in the TO-TLIF group) were loss of follow-up after discharge. And the remaining 73 patients were followed up for at least 2 years. No statistically significant difference was observed in the terms of age, sex, BMI, slippage grade, and surgical segments. The MIS-TLIF group had a longer operation and fluoroscopy time compared with the TO-TLIF group. But the MIS-TLIF group was associated with less blood loss, ambulation time, hospital stay, and time of return to work. In each group, significant improvement were observed in BP-VAS, ODI and vertebral slip ratio at any time-point of follow-up when compared with the preoperative condition. When the time-point of follow-up was less than 1 year, the MIS-TLIF group had significant advantages in the BP-VAS and ODI compared with TO-TLIF group. But no significant difference was observed in the BP-VAS and ODI at either 12 month follow-up or the last follow-up. Besides, no statistical difference was detected in vertebral slip ratio at any time-point of follow-up between the two groups. Successful intervertebral bone fusion was found in all patients and no significant difference was found in the incidence of total complications. Thus, we considered that MIS-TLIF and TO-TLIF both achieve satisfactory clinical efficacy in the treatment of low-grade single-segment LDS. But MIS-TLIF appears to be a more efficacious and safe technique with reduced tissue damage, less blood loss and quicker recovery.

Direct Pars Defect Tubular Decompression and TLIF for the Treatment of Low-Grade Adult Isthmic Spondylolisthesis: Surgical Challenges and Nuances of a Muscle-Sparing Minimally Invasive Approach

We present an illustrative report on the use of a minimally invasive, muscle-sparing, direct pars defect decompression with transforaminal lumbar interbody fusion (TLIF) and instrumentation for the treatment of low-grade adult isthmic spondylolysis with spondylolisthesis and discuss the surgical challenges and nuances associated with the technique.

Expandable Interbody Fusion Cages: An Editorial on the Surgeon's Perspective on Recent Technological Advances and Their Biomechanical Implications

BACKGROUND

Expandable cages have gone through several iterations since they first appeared on the market in the early 2000s. Their development was prompted by some common problems associated with static interbody cages, including migration, expulsion, dural or neural traction injury, and pseudarthrosis.

OBJECTIVE

To summarize current technological advances from earlier expandable lumbar interbody fusion devices to implants with vertical and medial-to-lateral expansion mechanisms.

METHODS

The authors review the currently available expandable cage designs, the incremental technological advances, and how these devices impact minimally invasive surgery interbody procedures and clinical outcomes. The strategic concepts intended to improve the minimally invasive application of expandable interbody fusion implants are reviewed from a surgeon's perspective in a clinical context to discuss how their use may improve patient outcomes.

CONCLUSIONS

The geometrical configuration, effective stiffness of composite multi-material cage designs may impact the bone-implant contact area with the endplates. Hybridization strategies of expandable cage technology with modern minimally invasive and endoscopic spinal surgery techniques are presented by outlining their advantages and disadvantages.

LEVEL OF EVIDENCE

1 CLINICAL RELEVANCE: Systematic review.

Endoscopic Transforaminal Lumbar Interbody Fusion With a Single Oblique PEEK Cage and Posterior Supplemental Fixation

BACKGROUND

To demonstrate the feasibility of an endoscopically assisted minimally invasive surgery transforaminal lumbar interbody fusion (MIS-TLIF) and to study clinical outcomes with the use of a static oblique bullet-shaped cannulated poly-ether-ether-ketone (PEEK) lumbar interbody fusion cage in conjunction with platelet enriched plasma infused allograft cancellous chips and posterior supplemental fixation.

METHODS

In this retrospective study of 43 patients who underwent endoscopically assisted MIS-TLIF for spondylolisthesis (53.5%) and stenosis (46.3%), the Oswestry Disability Index, the visual analog scale (VAS) for back and leg pain, and the modified Macnab criteria were used as primary clinical outcome measures. Clinical outcomes were cross-tabulated against fusion grade using the Bridwell classification of interbody fusion.

RESULTS

The majority of patients (90.7%) had excellent (8/43; 18.6%) and good (31/43; 72.1%) Macnab outcomes. There were significant VAS back score reductions from an average preoperative values of 8.9070 to a postoperative VAS score of 3.8605, and a score of 2.7674 at final follow-up (P < .0001). The reductions in the VAS leg scores were also significant from preoperative score of 5.58 to a postoperative value of 2.16, and a final follow-up score of 1.67 (P < .0001); the Oswestry Disability Index score went from a preoperative value of 54.4 to 23.3 postoperatively and 18.5 at the final follow-up (P < .0001). The vast majority of patients (92.9%) with Bridwell grade I fusion had excellent and good Macnab outcomes (P = .027).

CONCLUSIONS

The authors recommend the use of an endoscope as an adjunct to MIS-TLIF, a minimally invasive spinal surgery technique in which many surgeons may be well versed and have a great deal of experience. Clinical outcomes with the endoscopic interbody fusion procedure with a static PEEK cage in conjunction with platelet-enriched bone allograft were favorable.

LEVEL OF EVIDENCE

3.

CLINICAL RELEVANCE

Feasibility study.

Awake minimally invasive transforaminal lumbar interbody fusion with a pedicle-based retraction system

OBJECTIVE

Recently there has been increasing interest in the use of regional anesthesia for minimally-invasive transforaminal lumbar interbody fusion (TLIF) and laminectomy, with the goal of reducing the side effects and risks associated with general anesthesia and also to improve patient satisfaction. The goal of this technical note is to describe important perioperative aspects to safely perform an awake spine surgery and to describe a novel technique to preform minimally-invasive TLIF using a pedicle-based retraction system.

METHODS

We report our patient selection criteria, perioperative anesthesia protocol and surgical technique for awake TLIF with the Maximum Access Surgery (MAS) TLIF Retraction System. We describe an illustrative case of a 66-year-old female that presented with leg pain, lumbar MRI revealed a grade one spondylolisthesis at L4-5 with severe canal stenosis. She underwent a L4-5 Awake MIS TLIF using the MAS TLIF Retraction System.

RESULTS

The first 10 awake TLIF we performed with the MAS TLIF Retraction System had a mean procedure time of 117.3 min with a standard deviation (SD) of 13, and a mean total OR time of 151 min, SD 14.5. No surgery was converted under general anesthesia. No intraoperative complications were reported. Average length of stay was 1.3 ± 0.46 days.

CONCLUSION

Awake MAS TLIF is a safe and effective technique, with the advantage of reducing the risk and side effect of general anesthesia and the approach-associated damage to soft tissues and morbidity. The pedicle-based distraction allows easier access to the intervertebral disc space for both disc preparation and cage placement.

Two-Year Clinical and Radiographic Outcomes of Expandable Interbody Spacers Following Minimally Invasive Transforaminal Lumbar Interbody Fusion: A Prospective Study

BACKGROUND

The advantages of minimally invasive surgery for transforaminal lumbar interbody fusion (MIS TLIF) are well documented and include decreased blood loss, shorter length of hospital stay, and reduced perioperative costs. Clinical evidence for the use of expandable interbody spacers in conjunction with MIS TLIF, however, is scarce. This study sought to examine the clinical and radiographic outcomes of patients undergoing MIS TLIF with an expandable spacer.

METHODS

Forty patients from 4 institutions who underwent MIS TLIF with an expandable spacer were included in this study and followed for 24 months. Investigator assessment of the surgical technique was reported. Patient self-reported outcomes included Visual Analog Scale (VAS), Oswestry Disability Index (ODI), and Short Form 36 (SF-36) physical and mental component scores. Disc height, foraminal height, segmental and lumbar lordosis, and fusion were also assessed.

RESULTS

Investigators reported that intraoperative insertion, impaction, number of passes through the neural structures, and fit were better with an expandable spacer than a static spacer. Significant improvements in VAS, ODI, and SF-36 were reported as early as 6 weeks postoperatively and maintained through 24 months. Mean intervertebral and foraminal heights improved significantly from the preoperative time interval to as early as 6 weeks postoperatively and maintained through 24 months. There were no cases of spacer migration, subsidence, or collapse.

CONCLUSIONS

The use of an expandable interbody spacer in combination with MIS TLIF resulted in positive investigator assessments, immediate and progressive symptom relief, significant radiographic improvements, and no spacer-related complications.

Evaluation of Health-related Quality of Life Improvement in Patients Undergoing Spine Versus Adult Reconstructive Surgery

STUDY DESIGN

Retrospective analysis of outcomes in single-level spine and primary hip and knee arthroplasty patients.

OBJECTIVE

The aim of this study was to compare baseline and postoperative outcomes in patients undergoing spine surgery procedures with total hip arthroplasty (THA) and total knee arthroplasty (TKA) to further define outcomes in orthopedic surgery.

SUMMARY OF BACKGROUND DATA

Computer-adaptive Patient Reported Outcome Information System (PROMIS) allows for standardized assessment of the health-related quality of life across different disease states.

METHODS

Patients who underwent spine surgery (anterior cervical discectomy and fusion, cervical disc replacement, lumbar laminectomy, microscopic lumbar discectomy, transforaminal lumbar interbody fusion or adult reconstruction surgery [THA, TKA]) were grouped. Mean Charlson Comorbidity Index (CCI), Baseline (BL), and 6-month PROMIS scores of physical function, pain interference, and pain intensity were determined. Paired t tests compared differences in CCI, BL, 6 months, and change in PROMIS scores for spine and adult reconstruction procedures.

RESULTS

A total of 304 spine surgery patients (age = 58.1 ± 15.6; 42.9% female) and 347 adult reconstruction patients (age = 62.9 ± 11.8; 54.1% Female) were compared. Spine surgery groups had more disability and pain at baseline than adult reconstruction patients according to physical function ([21.0, 22.2, 9.07, 12.6, 10.4] vs. [35.8, 35.0], respectively, P < 0.01), pain interference ([80.1, 74.1, 89.6, 92.5, 90.6] vs. [64.0, 63.9], respectively, P < 0.01), and pain intensity ([53.0, 53.1, 58.3, 58.5, 56.1] vs. [53.4, 53.8], respectively, P < 0.01). At 6 months, spine surgery patients remained more disabled and had more pain compared to adult reconstruction patients. Over the 6-month timespan, spine patients experienced greater improvements than adult reconstruction patients in terms of physical function ([+8.7, +22.2, +9.7, +12.9, +12.1] vs. [+5.3, +3.9], respectively, P < 0.01) and pain interference scores ([-15.4,-28.1, -14.7, -13.1, -12.3] vs. [-8.3, -6.0], respectively, P < 0.01).

CONCLUSION

Spinal surgery patients had lower BL and 6-month PROMIS scores, but greater relative improvement in PROMIS scores compared to adult reconstruction patients.

LEVEL OF EVIDENCE

3.

Does Percutaneous Lumbosacral Pedicle Screw Instrumentation Prevent Long-Term Adjacent Segment Disease after Lumbar Fusion?

STUDY DESIGN

Retrospective cohort study.

PURPOSE

To assess long-term clinical outcomes of adjacent segment disease (ASD) in patients who underwent lumbar interbody fusion with percutaneous pedicle screw (PS) instrumentation.

OVERVIEW OF LITERATURE

ASD is a well-known sequela of spinal fusion, and is reported to occur at a rate of 2%-3% per year. There is debate as to whether ASD is a result of the instrumentation and fusion method or is the natural history of the patient's disease. Minimally invasive percutaneous PS augmentation of lumbar interbody fusion aims to prevent the disruption of posterior soft tissue stabilizers.

METHODS

From 2004-2014, 419 consecutive patients underwent anterior, lateral, or minimally invasive transforaminal lumbar interbody fusion with percutaneous PS placement at a single institution. The mean follow-up was 4.5 years. The primary outcome measure was reoperation due to ASD. Patients were divided into two cohorts: those who underwent revision surgery secondary to ASD and those who did not require further surgery. Radiographic parameters were performed using postoperative radiographs. Patients with a pelvic incidence-lumbar lordosis (PI-LL) mismatch >10° were noted.

RESULTS

Revision proportion secondary to ASD was 4.77% (n=20). Mean time to revision surgery was 2.5 years. Revision rate secondary to ASD was 1.1% per year. Patients who developed ASD were younger than those who did not (50.5 vs. 56.9 years, p=0.015). There was no difference in number of levels fused between cohorts. Revision proportion secondary to ASD was similar between approaches (anterior, lateral, minimally invasive). There was no significant difference in PI-LL mismatch between those who underwent revision for ASD and those who did not (22.2% vs. 18.8%, p=0.758).

CONCLUSIONS

ASD rates in patients who underwent percutaneous PS placement were lower than those previously published after open PS placement, possibly related to greater preservation of the posterior stabilizing elements of the lumbar spine.

Complications associated with L4-5 anterior retroperitoneal trans-psoas interbody fusion: a single institution series

Background

Lateral lumbar interbody fusion (LLIF), first described in the literature in 2006 by Ozgur et al., involves direct access to the lateral disc space via a retroperitoneal trans-psoas tubular approach. Neuromonitoring is vital during this approach since the surgical corridor traverses the psoas muscle where the lumbar plexus lies, risking injury to the lumbosacral plexus that could result in sensory or motor deficits. The risk of neurologic injury is especially higher at L4-5 due to the anatomy of the plexus at this level. Here we report our single-center clinical experience with L4-5 LLIF.

Methods

A retrospective chart review of all patients who underwent an L4-5 LLIF between May 2016 and March 2019 was performed. Baseline demographics and clinical characteristics, such as body mass index (BMI), medical comorbidities, surgical history, tobacco status, operative time and blood loss, length of stay (LOS), and post-op complications were recorded.

Results

A total of 220 (58% female and 42% male) cases were reviewed. The most common presenting pathology was spondylolisthesis. The average age, BMI, operative time, blood loss, and LOS were 64.6 years, 29 kg/m², 214 min, 75 cc, and 2.5 days respectively. A review of post-operative neurologic deficits revealed 31.4% transient hip flexor weakness and 4.5% quadricep weakness on the approach side. At 3-week follow-up, 9.1% of patients experienced mild hip flexor weakness (4 or 4+/5), 0.9% reported mild quadricep weakness, and 9.5% reported anterior thigh dysesthesias; 93.2% of patients were discharged home and 2.3% were readmitted within the first 30 days post discharge. Female sex, higher BMI and longer operative time were associated with hip flexor weakness.

Conclusions

LLIF at L4-5 is a safe, feasible, and versatile approach to the lumbar spine with an acceptable approach-related sensory and motor neurologic complication rates.

Clinical and Radiological Results After Minimally Invasive Transpsoas Lateral Access Surgery for Degenerative Lumbar Stenosis

STUDY DESIGN

Prospective cohort study.

OBJECTIVE

The lateral transpsoas access is a retroperitoneal approach for the lumbar spine to perform the lateral lumbar interbody fusion (LLIF), an intersomatic arthrodesis performed with a cage placed on the lateral borders of the epiphyseal ring. The procedure can be used to provide indirect decompression of the nervous structures through the discectomy and restoration of the disc height. The objective of the present study was to evaluate the indirect decompression following LLIF both with radiological and clinical parameters.

METHODS

Prospective clinical and radiological study in a single center with 20 patients diagnosed with 1- or 2-level degenerative lumbar stenosis. Radiological analysis on magnetic resonance imaging included foramen height, canal area, canal diameter, and disc height. Clinical outcomes included visual analogue scale (VAS) and Oswestry Disability Index (ODI) collected up to 12 months. Complications and reoperations were recorded.

RESULTS

In total, 25 levels were treated. No reoperation was required. Disc height was increased by an average of 25% (P < .001). The canal area increased from 109 to 149 mm² (P < .001) and from 9.3 to 12.2 mm (P < .001) in anteroposterior diameter. The foramen area demonstrated the effect of indirect decompression on both sides (P < .001). The height of the foramen showed significant average increase of 2.8 mm (P < .001). The results from VAS and ODI questionnaires confirmed the clinical effect of indirect decompression.

CONCLUSION

We observed that indirect decompression by the LLIF method is feasible both radiologically and clinically with a low rate of complications and reoperations.

Enhanced Recovery After Surgery Trends in Adult Spine Surgery: A Systematic Review

BACKGROUND

Enhanced Recovery After Surgery (ERAS) is a multimodal, multidisciplinary approach to optimizing the postsurgical recovery process through preoperative, perioperative, and postoperative interventions. ERAS protocols are emerging quickly within orthopedic spine surgery, yet there is a lack of consensus on optimal ERAS practices.

OBJECTIVE

The aim of this systematic review is to identify and discuss the trends in spine ERAS protocols and the associated outcomes.

METHODS

A literature search on PubMed was conducted to identify clinical studies that implemented ERAS protocols for various spine procedures in the adult population. The search included English-language literature published through December 2019. Additional sources were retrieved from the reference lists of key studies. Studies that met inclusion criteria were identified manually. Data regarding the study population, study design, spine procedures, ERAS interventions, and associated outcome metrics were extracted from each study that met inclusion criteria.

RESULTS

Of the 106 studies identified from the literature search, 22 studies met inclusion criteria. From the ERAS protocols in these studies, common preoperative elements include patient education and modified preoperative nutrition regimens. Perioperative elements include multimodal analgesia and minimally invasive surgery. Postoperative elements include multimodal pain management and early mobilization/rehabilitation/nutrition regimens. Outcomes from ERAS implementation include significant reductions in length of stay, cost, and opioid consumption. Although these trends were observed, there remained great variability among the ERAS protocols, as well as in the reported outcomes.

CONCLUSIONS

ERAS may improve cost-effectiveness to varying degrees for spinal procedures. Specifically, the use of multimodal analgesia may reduce overall opioid consumption. However, the benefits of ERAS likely will vary based on the specific procedure.

CLINICAL RELEVANCE

This review contributes to the assessment of ERAS protocol implementation in the field of adult spine surgery.

Does minimally invasive spine surgery reduce the rate of perioperative medical complications? A retrospective single-center experience of 1435 degenerative lumbar spine surgeries

PURPOSE

It is unclear if minimally invasive techniques reduce the rate of perioperative complications when compared to traditional open approaches to the lumbar spine. Our aim was to evaluate perioperative complications in patients that underwent MIS and conventional open techniques for degenerative lumbar pathology.

METHODS

A retrospective review of a prospectively collected database identified 1435 patients that underwent surgery for degenerative lumbar pathology from January 2013-2016. We evaluated the rates of deep vein thrombosis, pulmonary embolism, urinary tract infection, and pneumonia. Groups were analyzed based on decompression alone as compared with decompression and fusion for both MIS and traditional open techniques.

RESULTS

Patients that underwent traditional open lumbar decompression surgery were more likely to develop a DVT (P = .01) than those undergoing MIS decompression. There was no significant difference in rates of PE (P = .99), UTI (P = .24), or pneumonia (P = .56). Patients that underwent traditional open lumbar fusion surgery compared to MIS fusion were also more likely to have a PE (P = .03). There was no significant difference in rates of DVT (P = .22), UTI (P = .43), or pneumonia (P = .24).

CONCLUSION

Minimally invasive spinal surgery was found to reduce the rate of DVT for decompression surgeries and reduce the rate of PE for fusion surgeries.

Minimally Invasive Spine Lumbar Surgery in Obese Patients: A Systematic Review and Meta-Analysis

BACKGROUND

Transforaminal lumbar interbody fusion (TLIF) is the treatment of choice for lumbar spinal stenosis and spondylolisthesis. The procedure can be performed through a traditional open approach (O-TLIF) or through minimally invasive techniques (MI-TLIF). Spinal surgeries in obese patients can pose risks, including increased rates of infection and thromboembolic events.

QUESTIONS/PURPOSES

We sought to systematically review the literature on the differences between MI-TLIF and O-TLIF in the obese patient in terms of complication rate, functional outcomes, blood loss, and length of hospital stay.

METHODS

We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to systematically search PubMed, Embase, Web of Science, and the Cochrane Library for studies published through February 2019 and identified those comparing the outcomes of O-TLIF and MI-TLIF in obese patients. The primary outcome was complication rate (total, infections, dural tears); secondary outcomes were blood loss, length of hospital stay, and functional scores. Two authors independently reviewed the studies using the Newcastle-Ottawa Scale, and data were pooled using the Mantel-Haenszel random-effects model.

RESULTS

In the sample of 430 patients, the average age was 53.5 years, there were 153 men and 203 women, and the average body mass index was 33.6. Complications were significantly higher in O-TLIF than in MI-TLIF (OR = 0.420 [95% CI: 0.199, 0.887]; I ² = 45.20%). No difference was detected between the two groups for visual analog scale back pain scores and Oswestry Disability Index scores between the pre-operative and last follow-up visits (SMD = -0.034 [95% CI -0.695, 0.627]; I ² = 62.14% and SMD = 0.617 [95% CI: -1.082, 2.316]; I ² = 25%, respectively). Blood loss was significantly lower in MI-TLIF compared to O-TLIF (SMD = -426.736 [95% CI: -490.720, -362.752]; I ² = 70.53%), as was the duration of hospital stay (SMD = -1.079 [95% CI: -1.591, -0.208]; I ² = 84.3%).

CONCLUSION

MI-TLIF has equivalent efficacy to O-TLIF in obese patients at long-term follow-up. In addition, complication rate, blood loss, and length of hospital stay were lower in MI-TLIF than in O-TLIF.

Microendoscopic discectomy versus minimally invasive transforaminal lumbar interbody fusion for lumbar spinal stenosis without spondylolisthesis

Micoendoscopic discectomy (MED) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) has become alternatives of the traditional open decompression surgery alone and decompression plus fusion surgery in the treatment of lumbar spinal stenosis (LSS). To date, there is no study focusing on the comparison of clinical outcomes after MED and MIS-TLIF for LSS without spondylolisthesis.Four hundred ninety-seven patients who underwent MED (236 cases) or MIS-TLIF (261 cases) for LSS without spondylolisthesis were included in this study. Perioperative outcomes (hospital stay, operation time and blood loss), cost, functional scores (Oswestry Disability Index, 12-item short form health survey) with a 24-month follow-up visit, complication and reoperation condition within 24 months after surgery were recorded and assessed.No significant difference of clinical outcomes over time was observed between these 2 surgical approaches. Compared with MIS-TLIF, MED was associated with greater satisfaction at 1-month time point postoperatively, whereas this effect was equalized at 3-month time point postoperatively. MED brought advantages in shorter hospital stay, shorter operation time, less blood loss, and less cost over MIS-TLIF.There was no significant difference in 24-month function scores over time between MED group and MIS-TLIF group. Compared with MIS-TLIF, MED could result in a better perioperative effect and less cost.

Comparison of Outcomes of Oblique Lateral Interbody Fusion with Percutaneous Posterior Fixation in Lateral Position and Minimally Invasive Transforaminal Lumbar Interbody Fusion for Degenerative Spondylolisthesis

Study Design

Single-center retrospective study.

Purpose

To compare the physical function and quality of life (QOL) parameters of two minimally invasive surgical (MIS) procedures: oblique lateral interbody fusion with percutaneous posterior fixation in lateral position (OLIF-LPF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for single-level degenerative spondylolisthesis (DS).

Overview of Literature

To date, many options for the surgical treatment of lumbar DS and reports have described the effectiveness of minimally invasive lateral access surgery and MIS-TLIF. However, there is still a paucity of comparative data regarding the physical function and QOL outcomes of OLIF and MIS-TLIF.

Methods

Eighty-six patients were enrolled in this study (group O: OLIF-LPF, n=38; group T: MIS-TLIF, n=48). We evaluated the operation time, estimated blood loss (EBL), postoperative laboratory data, preoperative and postoperative radiographic parameters, overall functional outcome with the Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ) effectiveness rate, and Visual Analog Scale (VAS) score for low back pain, leg pain, and leg numbness.

Results

No statistical differences in operation time, EBL, and C-reactive protein level, 5 days postoperatively, between groups O and T. With respect to radiological outcome, preoperative and postoperative disc height change was significantly greater in group O than in group T (3.8 vs. 1.8 mm, p<0.05). Both groups showed postoperative improvements in the clinical outcome scores of all JOABPEQ domains, but the effectiveness rate increase in the psychological domain was significantly higher in group O than in group T (47.1% vs. 14.6%, p<0.05). No differences in the preoperative and postoperative VAS score change were noted between the two groups in any of the items.

Conclusions

The changes in physical function and QOL parameters after OLIF-LPF and MIS-TLIF were almost equivalent; however, OLIF-LPF had significant superiority in the psychological domain.

Systematic Review of Cost-Effectiveness Analyses in U.S. Spine Surgery

BACKGROUND

Increasing costs put the value of spine surgery under scrutiny. In health economics, cost-effectiveness analyses (CEA) are used to compare the value of competing procedures. However, inconsistent methodology prevents standardization and implementation of recommendations. The goal of this study is to perform a systematic review of all U.S. CEAs in spine surgery reported to date, highlight their strengths and weaknesses, and define metrics essential for high-quality CEAs.

METHODS

We followed AMSTAR systematic review methods, identifying all U.S. spine surgery CEAs reported to March 2019 with a structured, reproducible search of PubMed, Embase, and the Tufts CEA Registry.

RESULTS

We identified 40 CEA studies. Twelve (30%) used outcome data from a randomized controlled trial. To calculate costs, 22 (55%) used allowed charges but costing methods were often unclear or imprecise. Studies applying discounting had mean follow-up of 5.92 years compared with 3.00 years for studies without. Eleven of 15 (73%) cervical studies compared cervical disc arthroplasty with anterior cervical discectomy and fusion, finding cervical disc arthroplasty to be cost-effective (<$100,000/quality-adjusted life year) for 1-level and 2-level procedures. Eleven of 25 lumbar studies (44%) compared operative with nonoperative interventions for intervertebral disc herniation, lumbar stenosis, and lumbar spondylolisthesis. Lumbar studies comparing surgical with nonoperative intervention found surgery at least cost-effective for intervertebral disc herniation and lumbar stenosis, but cost-effective only for lumbar spondylolisthesis at 4 years follow-up. Most studies (70%) lacked appropriate sensitivity analyses.

CONCLUSIONS

Costing methodology remains obscure and inconsistent and incremental cost-effectiveness ratio results incomparable. The language of costing methodology must be standardized and sensitivity analyses of outcome and cost inputs mandatory for publication.

Cost-effectiveness Applications of Patient-reported Outcome Measures (PROMs) in Spine Surgery

Because of the rising health care costs in the United States, there has been a focus on value-based care and improving the cost-effectiveness of surgical procedures. Patient-reported outcome measures (PROMs) can not only give physicians and health care providers immediate feedback on the well-being of the patients but also be used to assess health and determine outcomes for surgical research purposes. Recently, PROMs have become a prominent tool to assess the cost-effectiveness of spine surgery by calculating the improvement in quality-adjusted life years (QALY). The cost of a procedure per QALY gained is an essential metric to determine cost-effectiveness in universal health care systems. Common patient-reported outcome questionnaires to calculate QALY include the EuroQol-5 dimensions, the SF-36, and the SF-12. On the basis of the health-related quality of life outcomes, the cost-effectiveness of various spine surgeries can be determined, such as cervical fusions, lumbar fusions, microdiscectomies. As the United States attempts to reduce costs and emphasize value-based care, PROMs may serve a critical role in spine surgery moving forward. In addition, PROM-driven QALYs may be used to analyze novel spine surgical techniques for value-based improvements.

Index episode-of-care propensity-matched comparison of transforaminal lumbar interbody fusion (TLIF) techniques: open traditional TLIF versus midline lumbar interbody fusion (MIDLIF) versus robot-assisted MIDLIF

OBJECTIVE

Posterior fixation with interbody cage placement can be accomplished via numerous techniques. In an attempt to expedite recovery by limiting muscle dissection, midline lumbar interbody fusion (MIDLIF) has been described. More recently, the authors have developed a robot-assisted MIDLIF (RA-MIDLIF) technique. The purpose of this study was to compare the index episode-of-care (iEOC) parameters between patients undergoing traditional open transforaminal lumbar interbody fusion (tTLIF), MIDLIF, and RA-MIDLIF.

METHODS

A retrospective review of a prospective, multisurgeon surgical database was performed. Consecutive patients undergoing 1- or 2-level tTLIF, MIDLIF, or RA-MIDLIF for degenerative lumbar conditions were identified. Patients in each cohort were propensity matched based on age, sex, smoking status, BMI, diagnosis, American Society of Anesthesiologists (ASA) class, and number of levels fused. Index EOC parameters such as length of stay (LOS), estimated blood loss (EBL), operating room (OR) time, and actual, direct hospital costs for the index surgical visit were analyzed.

RESULTS

Of 281 and 249 patients undergoing tTLIF and MIDLIF, respectively, 52 cases in each cohort were successfully propensity matched to the authors' first 55 RA-MIDLIF cases. Consistent with propensity matching, there was no significant difference in age, sex, BMI, diagnosis, ASA class, or levels fused. Spondylolisthesis was the most common indication for surgery in all cohorts. The mean total iEOC was similar across all cohorts. Patients undergoing RA-MIDLIF had a shorter average LOS (1.53 days) than those undergoing either MIDLIF (2.71 days) or tTLIF (3.58 days). Both MIDLIF and RA-MIDLIF were associated with lower EBL and less OR time compared with tTLIF.

CONCLUSIONS

Despite concerns for additional cost and time while introducing navigation or robotic technology, a propensity-matched comparison of the authors' first 52 RA-MIDLIF surgeries with tTLIF and MIDLIF showed promising results for reducing OR time, EBL, and LOS without increasing cost.

Risk Factors for Medical and Surgical Complications After Single-Level Minimally Invasive Transforaminal Lumbar Interbody Fusion

Background

The prevention of perioperative and postoperative complications is necessary to avoid poor postoperative outcomes and increased costs. Previous investigations have identified risk factors for complications after various spine procedures, but no such study exists in a population solely undergoing minimally invasive transforaminal lumbar interbody fusion (MIS TLIF). The purpose of this study is to determine risk factors for the development of complications up to 2 years after MIS TLIF procedures.

Methods

Patients who underwent primary, single-level MIS TLIF from 2007 to 2016 were retrospectively reviewed. The incidence of medical and surgical complications up to 2 years postoperatively was determined. Patients were categorized according to demographic, comorbidity, and procedural characteristics. Bivariate Poisson regression with robust error variance was used to determine if an association existed between patient characteristics and complication incidence. A final multivariate model including all patient characteristics as controls was created using backwards, stepwise regression until only those variables with P < .05 remained.

Results

390 patients were analyzed. Upon bivariate analysis, age >50 years (P = .025), diabetes mellitus (P = .001), and operative duration >105 minutes (P = .016) were associated with increased medical complication rates. Regarding surgical complications, age ≤50 years (P < .001), obesity (P = .012), and diabetes mellitus (P = .042) were identified as risk factors on bivariate analysis. Upon final multivariate analysis, operative time >105 minutes (P = .009) and diabetes mellitus (P = .001) were independent risk factors for medical complications. Independent risk factors for surgical complications on multivariate analysis included age ≤50 years (P < .001), diabetes mellitus (P = .002), and obesity (P = .030).

Conclusions

Diabetic patients and those who underwent longer operations were at increased risk of medical complications, while younger patients, obese patients and those also with diabetes mellitus were at increased risk of surgical complications up to 2 years after MIS TLIF. Practitioners can use this information to identify patients who require preventative care before their procedure or increased postoperative vigilance and monitoring after single-level MIS TLIF.

Level of Evidence

3.

Reductions in length of stay, narcotics use, and pain following implementation of an enhanced recovery after surgery program for 1- to 3-level lumbar fusion surgery

OBJECTIVELumbar fusion is typically associated with high degrees of pain and immobility. The implementation of an enhanced recovery after surgery (ERAS) approach has been successful in speeding the recovery after other surgical procedures. In this paper, the authors examined the results of early implementation of ERAS for lumbar fusion.METHODSBeginning in March 2018 at the authors' institution, all patients undergoing posterior, 1- to 3-level lumbar fusion surgery by any of 3 spine surgeons received an intraoperative injection of liposomal bupivacaine, immediate single postoperative infusion of 1-g intravenous acetaminophen, and daily postoperative visits from the authors' multidisciplinary ERAS care team. Non-English- or non-Spanish-speaking patients and those undergoing nonelective or staged procedures were excluded. Reviews of medical records were conducted for the ERAS cohort of 57 patients and a comparison group of 40 patients who underwent the same procedures during the 6 months before implementation.RESULTSGroups did not differ significantly with regard to sex, age, or BMI (all p > 0.05). Length of stay was significantly shorter in the ERAS cohort than in the control cohort (2.9 days vs 3.8 days; p = 0.01). Patients in the ERAS group consumed significantly less oxycodone-acetaminophen than the controls on postoperative day (POD) 0 (408.0 mg vs 1094.7 mg; p = 0.0004), POD 1 (1320.0 mg vs 1708.4 mg; p = 0.04), and POD 3 (1500.1 mg vs 2105.4 mg; p = 0.03). Postoperative pain scores recorded by the physical therapy and occupational therapy teams and nursing staff each day were lower in the ERAS cohort than in controls, with POD 1 achieving significance (4.2 vs 6.0; p = 0.006). The total amount of meperidine (8.8 mg vs 44.7 mg; p = 0.003) consumed was also significantly decreased in the ERAS group, as was ondansetron (2.8 mg vs 6.0 mg; p = 0.02). Distance ambulated on each POD was farther in the ERAS cohort, with ambulation on POD 1 (109.4 ft vs 41.4 ft; p = 0.002) achieving significance.CONCLUSIONSIn this very initial implementation of the first phase of an ERAS program for short-segment lumbar fusion, the authors were able to demonstrate substantial positive effects on the early recovery process. Importantly, these effects were not surgeon-specific and could be generalized across surgeons with disparate technical predilections. The authors plan additional iterations to their ERAS protocols for continued quality improvements.

Comparison of Minimally Invasive Versus Open Transforaminal Interbody Lumbar Fusion

STUDY DESIGN

Narrative review.

OBJECTIVES

In this review, we address the question of whether the literature supports the notion that minimally invasive transforaminal interbody fusion (MIS-TLIF) improves outcome as compared with open TLIF (open-TLIF). Short and long-term outcomes, fusion rate, and cost-effectiveness were reviewed.

METHODS

This is a narrative review using various databases. Open-TLIF and MIS-TLIF studies were included and posterior lumbar interbody fusion studies were excluded. A description of paramedian incision in surgical technique was essential to the definition of MIS-TLIF. The present review included 14 prospective observational studies and 6 randomized controlled trials.

RESULTS

With short-term outcomes, some studies indicate a better outcome with MIS-TLIF regarding intraoperative bleeding, hospital stay, time to ambulation, postoperative narcotic use, and time to resume work. Both MIS-TLIF and open-TLIF surgeries improved Oswestry Disability Index, back pain, and leg pain. Some studies show that MIS-TLIF resulted in lower back pain than open-TLIF. Radiation exposure was higher with MIS-TLIF. In the longer term, clinical outcomes were improved in both MIS and open TLIF groups. Fusion rates were more than 90% in both MIS-TLIF and open-TLIF. Cost-effectiveness and length of surgery had mixed results.

CONCLUSIONS

The potential benefits of MIS-TLIF might be present in the early recovery period after surgery. Long-term outcomes were similar with both MIS-TLIF and open-TLIF.

Risk factors predicting less favorable outcomes in endoscopic lumbar discectomies

Background

Endoscopic lumbar discectomy was among the first minimally invasive spine procedures commonly performed. As such, all the benefits of minimal invasion were seen, including less pain, less soft tissue destruction, and faster recovery. While outcomes compare favorably to micro and open discectomy, not all patients fare equally well. This paper examines independent risk factors to assess their correlation to suboptimal outcomes after endoscopic lumbar discectomy.

Methods

Retrospective analysis of clinical outcomes of 55 consecutive patients treated with endoscopic discectomy between June 2018 and March 2019 by the author. Primary outcome measures were postoperative reductions of visual analog score (VAS) for back and leg pain modified MacNab criteria as well as time to narcotic independence. Risk factors examined included smoking, facet disease, adjacent segments disc degeneration, obesity, alcohol abuse, and psychiatric illness.

Results

There were 31 males and 24 females with a mean age of 41.76±12.53. Most patients suffered from contained herniations (49.1%) followed by extruded herniations (18.2%). Follow-up ranged from 6-18 months. The most common surgical levels were L5-S1 level (30.9%), L4-S1 (29.1%), and L4-5 (25.5%). The mean return to work (RTW) was 23.83±26.01 weeks. The average body mass index (BMI) was 29.11±4.75. The average time for narcotic independence was 9.64±7.29 days. MacNab outcomes showed that 47.3% (26/55) had excellent, 36.4% good (20/55), 12.7% fair (7/55), and 3.6% had poor (2/55), respectively. The VAS scores for the back (7.69 to 2.65) and leg (6.78 to 2.65) pain reduced significantly (P<0.0001). Smoking (P=0.048), psychiatric disease (P=0.029), disc herniations larger than 10 mm, facet disease, obesity (BMI >30), diabetes, and alcohol abuse was associated with fair and poor MacNab outcomes.

Conclusions

Endoscopic lumbar discectomy safely and reliably reduces axial pain and radiculopathy from lumbar disc herniations. Risk factors associated with incomplete pain relief are large herniations, obesity, instability, smoking, advanced facet degeneration, and decreased ability to cope with the surgery.

Percutaneous Peripheral Nerve Stimulation for Chronic Low Back Pain: Prospective Case Series With 1 Year of Sustained Relief Following Short-Term Implant

INTRODUCTION

Percutaneous peripheral nerve stimulation (PNS) provides an opportunity to relieve chronic low back pain and reduce opioid analgesic consumption as an alternative to radiofrequency ablation and permanently implanted neurostimulation systems. Traditionally, the use of neurostimulation earlier in the treatment continuum has been limited by its associated risk, invasiveness, and cost.

METHODS

Percutaneous PNS leads (SPRINT MicroLead) were placed bilaterally to target the medial branches of the dorsal rami nerves under image guidance. The percutaneous leads were connected to miniature wearable stimulators (SPRINT PNS System) for the 1-month therapy period, after which the leads were removed. Pain and disability were assessed long-term up to 12 months after lead removal.

RESULTS

Substantial, clinically significant reductions in average pain intensity (≥50% reduction as measured by the Brief Pain Inventory Short Form) were experienced by a majority of subjects (67%) at end of treatment compared to baseline (average 80% reduction among responders; P < 0.05, analysis of variance; n = 9). Twelve months after the end of PNS treatment, a majority of subjects who completed the long-term follow-up visits experienced sustained, clinically significant reductions in pain and/or disability (67%, n = 6; average 63% reduction in pain intensity and 32-point reduction in disability among responders). No serious or unanticipated adverse events were reported.

CONCLUSIONS

This study challenges the long-held notion that a positive trial of PNS should be followed by a permanent implant in responders. Percutaneous PNS may serve as an effective neurostimulation therapy for patients with chronic low back pain and should be considered earlier in the treatment continuum as a motor-sparing means of avoiding opioids, denervation, and permanently implanted neurostimulation systems.

Comparison of Single-Level Open and Minimally Invasive Transforaminal Lumbar Interbody Fusions Presenting a Learning Curve

Background

Comparison of single-level open and minimally invasive transforaminal lumbar interbody fusions (O-TLIF and MI-TLIF) of a single surgeon and presentation of his MI-TLIF learning curve in a retrospective observational cohort study.

Methods

27 MI-TLIF and 31 O-TLIF patients, performed between 03/01/2013 and 03/31/2018, were compared regarding the operative time, blood loss, blood transfusion frequency, postoperative length of stay (LOS), and adverse events. An overall comparison of pre- and postoperative Oswestry Disability Index (ODI) results and Visual Analog Score (VAS) results of low back and leg pain was performed in the case of the two techniques. For a learning curve presentation, the MI-TLIF cases were compared and the optimal operative time was determined.

Results

The gender ratio and age did not differ in the groups. Operative time showed no difference (P=0.88) between the MI-TLIF (161.2 ± 33.7 minutes) and O-TLIF groups (160 ± 33.6 minutes). Intraoperative blood loss was less (P=0.88) between the MI-TLIF (161.2 ± 33.7 minutes) and O-TLIF groups (160 ± 33.6 minutes). Intraoperative blood loss was less (P=0.88) between the MI-TLIF (161.2 ± 33.7 minutes) and O-TLIF groups (160 ± 33.6 minutes). Intraoperative blood loss was less (P=0.88) between the MI-TLIF (161.2 ± 33.7 minutes) and O-TLIF groups (160 ± 33.6 minutes). Intraoperative blood loss was less (P=0.88) between the MI-TLIF (161.2 ± 33.7 minutes) and O-TLIF groups (160 ± 33.6 minutes). Intraoperative blood loss was less (P=0.88) between the MI-TLIF (161.2 ± 33.7 minutes) and O-TLIF groups (160 ± 33.6 minutes). Intraoperative blood loss was less (P=0.88) between the MI-TLIF (161.2 ± 33.7 minutes) and O-TLIF groups (160 ± 33.6 minutes). Intraoperative blood loss was less (P=0.88) between the MI-TLIF (161.2 ± 33.7 minutes) and O-TLIF groups (160 ± 33.6 minutes). Intraoperative blood loss was less (P=0.88) between the MI-TLIF (161.2 ± 33.7 minutes) and O-TLIF groups (160 ± 33.6 minutes). Intraoperative blood loss was less (P=0.88) between the MI-TLIF (161.2 ± 33.7 minutes) and O-TLIF groups (160 ± 33.6 minutes). Intraoperative blood loss was less (P=0.88) between the MI-TLIF (161.2 ± 33.7 minutes) and O-TLIF groups (160 ± 33.6 minutes). Intraoperative blood loss was less (p=0.88) between the MI-TLIF (161.2 ± 33.7 minutes) and O-TLIF groups (160 ± 33.6 minutes). Intraoperative blood loss was less (P=0.88) between the MI-TLIF (161.2 ± 33.7 minutes) and O-TLIF groups (160 ± 33.6 minutes). Intraoperative blood loss was less (P=0.88) between the MI-TLIF (161.2 ± 33.7 minutes) and O-TLIF groups (160 ± 33.6 minutes). Intraoperative blood loss was less (P=0.88) between the MI-TLIF (161.2 ± 33.7 minutes) and O-TLIF groups (160 ± 33.6 minutes). Intraoperative blood loss was less (P=0.88) between the MI-TLIF (161.2 ± 33.7 minutes) and O-TLIF groups (160 ± 33.6 minutes). Intraoperative blood loss was less (

Conclusions

Similar operative time and postoperative quality of life improvement can be achieved by MI-TLIF procedure as with O-TLIF, and additionally LOS and blood loss can be reduced. When comparing parameters, MI-TLIF can be an alternative option for O-TLIF with a similar complication profile. The learning curve of MI-TLIF can be steep, although it depends on the circumstances.

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

OBJECTIVE

The midline transforaminal lumbar interbody fusion (MIDLIF) using cortical screw fixation is a novel, minimally invasive procedure that may offer enhanced recovery over traditional open transforaminal lumbar interbody fusion (TLIF). Little information is available regarding the comparative cost-effectiveness of the MIDLIF over conventional TLIF. The purpose of this study was to compare cost-effectiveness of minimally invasive MIDLIF with open TLIF.

METHODS

From a prospective, multisurgeon, surgical database, a consecutive series of patients undergoing 1- or 2-level MIDLIF for degenerative lumbar conditions was identified and propensity matched to patients undergoing TLIF based on age, sex, smoking status, BMI, diagnosis, American Society of Anesthesiologists Physical Status Classification System (ASA) class, and levels fused. Direct costs at 1 year were collected, including costs associated with the index surgical visit as well as costs associated with readmission. Improvement in health-related quality of life was measured using EQ-5D and SF-6D.

RESULTS

Of 214 and 181 patients undergoing MIDLIF and TLIF, respectively, 33 cases in each cohort were successfully propensity matched. Consistent with propensity matching, there was no difference in age, sex, BMI, diagnosis, ASA class, smoking status, or levels fused. Spondylolisthesis was the most common indication for surgery in both cohorts. Variable direct costs at 1 year were $2493 lower in the MIDLIF group than in the open TLIF group (mean $15,867 vs $17,612, p = 0.073). There was no difference in implant (p = 0.193) or biologics (p = 0.145) cost, but blood utilization (p = 0.015), operating room supplies (p < 0.001), hospital room and board (p < 0.001), pharmacy (p = 0.010), laboratory (p = 0.004), and physical therapy (p = 0.009) costs were all significantly lower in the MIDLIF group. Additionally, the mean length of stay was decreased for MIDLIF as well (3.21 vs 4.02 days, p = 0.05). The EQ-5D gain at 1 year was 0.156 for MIDLIF and 0.141 for open TLIF (p = 0.821). The SF-6D gain at 1 year was 0.071 for MIDLIF and 0.057 for open TLIF (p = 0.551).

CONCLUSIONS

Compared with patients undergoing traditional open TLIF, those undergoing MIDLIF have similar 1-year gains in health-related quality of life, with total direct costs that are $2493 lower. Although the findings were not statistically significant, minimally invasive MIDLIF showed improved cost-effectiveness at 1 year compared with open TLIF.

Minimally invasive surgery for degenerative spondylolisthesis: transforaminal or oblique lumbar interbody fusion

Aim: To compare the outcomes of minimally invasive surgery (MIS) for degenerative spondylolisthesis transforaminal lumbar interbody fusion (TLIF) and oblique lumbar interbody fusion (OLIF). Materials & methods: The clinical and surgical characteristics and outcomes of 38 patients with MIS-OLIF and 55 with MIS-TLIF were retrospectively evaluated. Results: Procedures and hospital stay were shorter and blood loss was less, with MIS-OLIF than with MIS-OLIF. The clinical and radiographic outcomes were similar. Postoperative changes in disk height and foraminal dimension were greater and patient satisfaction was better with MIS-OLIF than with MIS-TLIF. Conclusion: The clinical findings associated with the two procedures were similar; but patients preferred MIS-OLIF, which is less invasive, to MIS-TLIF. Clinical trial registration number: ChiCTR1800019443.

Assessment of radiographic and clinical outcomes of an articulating expandable interbody cage in minimally invasive transforaminal lumbar interbody fusion for spondylolisthesis

OBJECTIVE The inability to significantly improve sagittal parameters has been a limitation of minimally invasive surgery for transforaminal lumbar interbody fusion (MIS TLIF). Traditional cages have a limited capacity to restore lordosis. This study evaluates the use of a crescent-shaped articulating expandable cage (Altera) for MIS TLIF. METHODS This is a retrospective review of 1- and 2-level MIS TLIF. Radiographic outcomes included differences in segmental and lumbar lordosis, disc height, evidence of fusion, and any endplate violations. Clinical outcomes included the numeric rating scale for leg and back pain and the Oswestry Disability Index (ODI) for low-back pain. RESULTS Thirty-nine patients underwent single-level MIS TLIF, and 5 underwent 2-level MIS TLIF. The mean age was 63.1 years, with 64% women. On average, spondylolisthesis was corrected by 4.3 mm (preoperative = 6.69 mm, postoperative = 2.39 mm, p < 0.001), the segmental angle was improved by 4.94° (preoperative = 5.63°, postoperative = 10.58°, p < 0.001), and segmental height increased by 3.1 mm (preoperative = 5.09 mm, postoperative = 8.19 mm, p < 0.001). At 90 days after surgery the authors observed the following: a smaller postoperative sagittal vertical axis was associated with larger changes in back pain at 90 days (r = -0.558, p = 0.013); a larger decrease in spondylolisthesis was associated with greater improvements in ODI and back pain scores (r = -0.425, p = 0.043, and r = -0.43, p = 0.031, respectively); and a larger decrease in pelvic tilt (PT) was associated with greater improvements in back pain (r = -0.548, p = 0.043). For the 1-year PROs, the relationship between the change in PT and changes in ODI and numeric rating scale back pain were significant (r = 0.612, p = 0.009, and r = -0.803, p = 0.001, respectively) with larger decreases in PT associated with larger improvements in ODI and back pain. Overall for this study there was a 96% fusion rate. Fourteen patients were noted to have endplate violation on intraoperative fluoroscopy during placement of the cage. Only 3 of these had progression of their subsidence, with an overall subsidence rate of 6% (3 of 49) visible on postoperative CT. CONCLUSIONS The use of this expandable, articulating, lordotic, or hyperlordotic interbody cage for MIS TLIF provides a significant restoration of segmental height and segmental lordosis, with associated improvements in sagittal balance parameters. Patients treated with this technique had acceptable levels of fusion and significant reductions in pain and disability.

Diminishing Clinical Returns of Multilevel Minimally Invasive Lumbar Interbody Fusion

STUDY DESIGN

Single institution retrospective clinical review.

OBJECTIVE

To investigate the relationship between levels fused and clinical outcomes in patients undergoing open and minimally invasive surgical (MIS) lumbar fusion.

SUMMARY OF BACKGROUND DATA

Minimally invasive spinal fusion aims to reduce the morbidity associated with conventional open surgery. As multilevel arthrodesis procedures are increasingly performed using MIS techniques, it is necessary to weigh the risks and benefits of multilevel MIS lumbar fusion as a function of fusion length.

METHODS

Patients undergoing <4 level lumbar interbody fusion were stratified by surgical technique (MIS or open), and grouped by fusion length: 1-level, 2-levels, 3+ levels. Demographics, Charlson Comorbidity Index (CCI), surgical factors, and perioperative complication rates were compared between technique groups at different fusion lengths using means comparison tests.

RESULTS

Included: 361 patients undergoing lumbar interbody fusion (88% transforaminal, 14% lateral; 41% MIS). Breakdown by fusion length: 63% 1-level, 22% 2-level, 15% 3+ level. Op-time did not differ between groups at 1-level (MIS: 233 min vs. Open: 227, P = 0.554), though MIS at 2-levels (332 min vs. 281) and 3+ levels (373 min vs. 323) were longer (P = 0.033 and P = 0.231, respectively). While complication rates were lower for MIS at 1-level (15% vs. 30%, P = 0.006) and 2-levels (13% vs. 27%, P = 0.147), at 3+ levels, complication rates were comparable (38% vs. 35%, P = 0.870). 3+ level MIS fusions had higher rates of ileus (13% vs. 0%, P = 0.008) and a trend of increased adverse pulmonary events (25% vs. 7%, P = 0.110). MIS was associated with less EBL at all lengths (all P < 0.01) and lower rates of anemia at 1-level (5% vs. 18%, P < 0.001) and 2-levels (7% vs. 16%, P = 0.193). At 3+ levels, however, anemia rates were similar between groups (13% vs. 15%, P = 0.877).

CONCLUSION

MIS lumbar interbody fusions provided diminishing clinical returns for multilevel procedures. While MIS patients had lower rates of perioperative complications for 1- and 2-level fusions, 3+ level MIS fusions had comparable complication rates to open cases, and higher rates of adverse pulmonary and ileus events.

LEVEL OF EVIDENCE

3.

An updated meta-analysis of clinical outcomes comparing minimally invasive with open transforaminal lumbar interbody fusion in patients with degenerative lumbar diseases

BACKGROUND & AIMS

Open-transforaminal lumbar interbody fusion (O-TLIF) is regarded as the standard (S) approach which is currently available for patients with degenerative lumbar diseases patients. In addition, minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) has proposed and gradually obtained popularity compared with O-TLIF procedures due to its beneficial outcomes in minimized tissue injury and quicker recovery. Nonetheless, debates exist concerning the use of MI-TLIF with its conflicting outcomes of clinical effect and safety in several publications. The purpose of the current study is to conduct an updated meta-analysis to provide eligible and systematical assessment available for the evaluation of the efficacy and safety of MI-TLIF in comparison with O-TLIF.

METHODS

Publications on the comparison of O-TLIF and MI-TLIF in treating degenerative lumbar diseases in last 5 years were collected. After rigorous reviewing on the eligibility of publications, the available data was further extracted from qualified trials. All trials were conducted with the analysis of the summary hazard ratios (HRs) of the interest endpoints, including intraoperative and postoperative outcomes.

RESULTS

Admittedly, it is hard to run a clinical RCT to compare the prognosis of patients undergoing O-TLIF and MI-TLIF. A total of 10 trials including non-randomized trials in the current study were collected according to our inclusion criteria. The pooled results of surgery duration indicated that MI-TLIF was highly associated with shorter length of hospital stay, less blood loss, and less complications. However, there were no remarkable differences in the operate time, VAS-BP, VAS-LP, and ODI between the 2 study groups.

CONCLUSION

The quantitative analysis and combined results of our study suggest that MI-TLIF may be a valid and alternative method with safe profile in comparison of O-TLIF, with reduced blood loss, decreased length of stay, and complication rates. While, no remarkable differences were found or observed in the operate time, VAS-BP, VAS-LP, and ODI. Considering the limited available data and sample size, more RCTs with high quality are demanded to confirm the role of MI-TLIF as a standard approach in treating degenerative lumbar diseases.

Minimally invasive transforaminal lumbar interbody fusion (MI-TLIF): A review of indications, technique, results and complications

Minimal access surgery has revolutionized most surgical disciplines and spine surgery is no exception. Minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) was devised to reduce the approach-related morbidity of open TLIF and has flourished in the last decade. With expanding indications, standardization of technique and equipment, publication of more studies on its results and complications being brought to light - an update of the existing knowledge on MI-TLIF is imminent. We provide a review of the indications, technique, results and complications of MI-TLIF while also highlighting its variations and utility in special situations.

Minimally Invasive versus Open Spine Surgery: What Does the Best Evidence Tell Us?

Background:

Spine surgery has been transformed significantly by the growth of minimally invasive surgery (MIS) procedures. Easily marketable to patients as less invasive with smaller incisions, MIS is often perceived as superior to traditional open spine surgery. The highest quality evidence comparing MIS with open spine surgery was examined.

Methods:

A systematic review of randomized controlled trials (RCTs) involving MIS versus open spine surgery was performed using the Entrez gateway of the PubMed database for articles published in English up to December 28, 2015. RCTs and systematic reviews of RCTs of MIS versus open spine surgery were evaluated for three particular entities: Cervical disc herniation, lumbar disc herniation, and posterior lumbar fusion.

Results:

A total of 17 RCTs were identified, along with six systematic reviews. For cervical disc herniation, MIS provided no difference in overall function, arm pain relief, or long-term neck pain. In lumbar disc herniation, MIS was inferior in providing leg/low back pain relief, rehospitalization rates, quality of life improvement, and exposed the surgeon to >10 times more radiation in return for shorter hospital stay and less surgical site infection. In posterior lumbar fusion, MIS transforaminal lumbar interbody fusion (TLIF) had significantly reduced 2-year societal cost, fewer medical complications, reduced time to return to work, and improved short-term Oswestry Disability Index scores at the cost of higher revision rates, higher readmission rates, and more than twice the amount of intraoperative fluoroscopy.

Conclusion:

The highest levels of evidence do not support MIS over open surgery for cervical or lumbar disc herniation. However, MIS TLIF demonstrates advantages along with higher revision/readmission rates. Regardless of patient indication, MIS exposes the surgeon to significantly more radiation; it is unclear how this impacts patients. These results should optimize informed decision-making regarding MIS versus open spine surgery, particularly in the current advertising climate greatly favoring MIS.

Open versus minimally invasive TLIF: literature review and meta-analysis

STUDY DESIGN

This study is a comparative, literature review.

OBJECTIVE

The aim of this study is to provide a comparative analysis of open vs. minimally invasive TLIF using a literature review and a meta-analysis. Lumbar interbody fusion is a well-established surgical procedure for treating several spinal disorders. Transforaminal lumbar interbody fusion (TLIF) was initially introduced in the early 1980s. To reduce approach-related morbidity associated with traditional open TLIF (OTLIF), minimally invasive TLIF (MITLIF) was developed. We aimed to provide a comparative analysis of open vs. minimally invasive TLIF using a literature review.

METHODS

We searched the online database PubMed (2005-2017), which yielded an initial 194 studies. We first searched the articles' abstracts. Based on our inclusion criteria, we excluded 162 studies and included 32 studies: 18 prospective, 13 retrospective, and a single randomized controlled trial. Operative time, blood loss, length of hospital stay, radiation exposure time, complication rate, and pain scores (visual analogue scale, Oswestry Disability Index) for both techniques were recorded and presented as means. We then performed a meta-analysis.

RESULTS

The meta-analysis for all outcomes showed reduced blood loss (P < 0.00001) and length of hospital stay (P < 0.00001) for MITLIF compared with OTLIF, but with increased radiation exposure time with MITLIF (P < 0.00001). There was no significant difference in operative time between techniques (P = 0.78). The complication rate was lower with MITLIF (11.3%) vs. OTLIF (14.2%), but not statistically significantly different (P = 0.05). No significant differences were found in visual analogue scores (back and leg) and Oswestry Disability Index scores between techniques, at the final follow-up.

CONCLUSION

MITLIF and OTLIF provide equivalent long-term clinical outcomes. MITLIF had less tissue injury, blood loss, and length of hospital stay. MITLIF is also a safe alternative in obese patients and, in experienced hands, can also be used safely in select cases of spondylodiscitis even with epidural abscess. MITLIF is also a cost-saving procedure associated with reduced hospital and social costs. Long-term studies are required to better evaluate controversial items such as operative time.

Summary of Guidelines for the Treatment of Lumbar Spondylolisthesis

Degenerative lumbar spondylolisthesis is a common cause of low back pain, affecting about 11.5% of the United States population. Patients with symptomatic lumbar spondylolisthesis may first be treated with conservative management strategies including, but not limited to, non-narcotic and narcotic pain medications, epidural steroid injections, transforaminal injections, and physical therapy. For well-selected patients who fail conservative management strategies, surgical management is appropriate. This article summarizes the guidelines for the treatment of lumbar spondylolisthesis.

Cost-effectiveness of microdiscectomy versus endoscopic discectomy for lumbar disc herniation

BACKGROUND CONTEXT

Microdiscectomy is a standard technique for the surgical treatment of lumbar disc herniation (LDH). Endoscopic discectomy (ED) is another surgical option that has become popular owing to reports of shorter hospitalization and earlier return to work. No study has evaluated health care costs associated with lumbar discectomy techniques and compared cost-effectiveness.

PURPOSE

To assess the cost-effectiveness of four surgical techniques for LDH: microdiscectomy (MD), transforaminal endoscopic lumbar discectomy (TELD), interlaminar endoscopic lumbar discectomy (IELD), and unilateral biportal endoscopic discectomy (UBED).

STUDY DESIGN AND SETTING

Retrospective analysis.

PATIENT SAMPLE

Patients who underwent either MD or ED for primary LDH with 1-year follow-up between the ages of 20 and 60 years old.

OUTCOME MEASURES

Incremental cost-effectiveness ratio (ICER).

METHODS

Five hundred sixty-five patients aged 20-60 years who underwent treatment using one of the four surgical techniques with at least 1-year follow-up were reviewed. Health care costs were defined as the sum of direct and indirect costs. The former included the covered and uncovered costs of the National Health Insurance from operation to 1-year follow-up; indirect costs included costs incurred by work loss. Direct and indirect costs were evaluated separately. ICER was determined using cost/quality-adjusted life year (QALY). Health care costs and ICER were compared statistically among the four surgical groups. Cost-effectiveness was compared statistically between MD and ED.

RESULTS

One hundred fifty-seven patients who underwent TELD, 132 for IELD, 140 for UBED, and 136 for MD were enrolled. The direct costs of TELD, IELD, UBED, and MD were $3,452.2±1,211.5, $3,907.3±895.3, $4,049.2±1,134.6, and $4,302.1±1,028.9, respectively (p<.01). The indirect costs of TELD, IELD, UBED, and MD were $574.5±495.9, $587.8±488.3, $647.4±455.6, and $759.7±491.7, respectively (p<.01). The 1-year QALY gains were 0.208 for TELD, 0.211 for IELD, 0.194 for UBED, and 0.186 for MD. ICER (costs/QALY) was the highest for MD ($34,840.4±25,477.9, p<.01). Compared with MD, ED saved an additional net of $8,064 per QALY (p<.01). There was no significant difference in the ICERs among the three endoscopic techniques.

CONCLUSIONS

ED was more cost-effective compared with MD at 1-year follow up.

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.

Trends in outpatient minimally invasive spine surgery

There has been a definite upward trend in outpatient minimally invasive spine (MIS) surgery over the past decade. This increasing prevalence has been driven by several factors including advanced MIS techniques, improvements in perioperative pain management, and economic necessity. There is now a myriad of different spine surgery procedures which can be effectively employed in the outpatient setting, and the concept of awake, endoscopic fusion surgery represents a notable advance in the field. Additionally, the use of multi-modality analgesic agents has shown significant promise in this arena and has become increasingly important in states where legislation affecting narcotic prescriptions have been enacted. Finally, with an aging population, the need for outpatient spine surgery has become imperative from an economic standpoint.

Using minimally invasive techniques adds to the value equation for select patients

Conditions of the spine are one of the most prevalent causes of global disability, and result in a considerable portion of total health expenditures. Surgical treatment of the spine has been demonstrated in multiple studies to be a cost-effective treatment option for many patients, especially with continuing improvements in surgical technique and instrumentation. Minimally invasive spine surgery (MISS), in particular, has evolved as a valuable option in treating certain patients. Numerous studies have analyzed minimally invasive techniques in regards to cost-effectiveness and other purported advantages. These advantages include conduciveness to outpatient settings, better perioperative and immediate post-operative benefits, and faster time to recovery. This article will describe the current literature on the advantages of MISS, specifically in regards to value and cost savings.

Cost-Effectiveness for Surgical Treatment of Degenerative Spondylolisthesis

Surgery for degenerative lumbar spondylolisthesis is significantly more cost-effective than nonsurgical management in patients who have failed to improve with a 6-week trial of nonsurgical management. Decompression plus fusion becomes more cost-effective compared with decompression alone at 2 years following surgery. Further study is needed to evaluate the most cost-effective fusion approach and augmentation strategy.

A comparison of minimally invasive transforaminal lumbar interbody fusion and decompression alone for degenerative lumbar spondylolisthesis

OBJECTIVE

The optimal minimally invasive surgery (MIS) approach for grade 1 lumbar spondylolisthesis is not clearly elucidated. In this study, the authors compared the 24-month patient-reported outcomes (PROs) after MIS transforaminal lumbar interbody fusion (TLIF) and MIS decompression for degenerative lumbar spondylolisthesis.

METHODS

A total of 608 patients from 12 high-enrolling sites participating in the Quality Outcomes Database (QOD) lumbar spondylolisthesis module underwent single-level surgery for degenerative grade 1 lumbar spondylolisthesis, of whom 143 underwent MIS (72 MIS TLIF [50.3%] and 71 MIS decompression [49.7%]). Surgeries were classified as MIS if there was utilization of percutaneous screw fixation and placement of a Wiltse plane MIS intervertebral body graft (MIS TLIF) or if there was a tubular decompression (MIS decompression). Parameters obtained at baseline through at least 24 months of follow-up were collected. PROs included the Oswestry Disability Index (ODI), numeric rating scale (NRS) for back pain, NRS for leg pain, EuroQol-5D (EQ-5D) questionnaire, and North American Spine Society (NASS) satisfaction questionnaire. Multivariate models were constructed to adjust for patient characteristics, surgical variables, and baseline PRO values.

RESULTS

The mean age of the MIS cohort was 67.1 ± 11.3 years (MIS TLIF 62.1 years vs MIS decompression 72.3 years) and consisted of 79 (55.2%) women (MIS TLIF 55.6% vs MIS decompression 54.9%). The proportion in each cohort reaching the 24-month follow-up did not differ significantly between the cohorts (MIS TLIF 83.3% and MIS decompression 84.5%, p = 0.85). MIS TLIF was associated with greater blood loss (mean 108.8 vs 33.0 ml, p < 0.001), longer operative time (mean 228.2 vs 101.8 minutes, p < 0.001), and longer length of hospitalization (mean 2.9 vs 0.7 days, p < 0.001). MIS TLIF was associated with a significantly lower reoperation rate (14.1% vs 1.4%, p = 0.004). Both cohorts demonstrated significant improvements in ODI, NRS back pain, NRS leg pain, and EQ-5D at 24 months (p < 0.001, all comparisons relative to baseline). In multivariate analyses, MIS TLIF—as opposed to MIS decompression alone—was associated with superior ODI change (β = −7.59, 95% CI −14.96 to −0.23; p = 0.04), NRS back pain change (β = −1.54, 95% CI −2.78 to −0.30; p = 0.02), and NASS satisfaction (OR 0.32, 95% CI 0.12–0.82; p = 0.02).

CONCLUSIONS

For symptomatic, single-level degenerative spondylolisthesis, MIS TLIF was associated with a lower reoperation rate and superior outcomes for disability, back pain, and patient satisfaction compared with posterior MIS decompression alone. This finding may aid surgical decision-making when considering MIS for degenerative lumbar spondylolisthesis.

Restoration of lumbar lordosis after minimally invasive transforaminal lumbar interbody fusion: a systematic review

BACKGROUND

Transforaminal lumbar interbody fusion (TLIF) is a well-accepted surgical technique for the treatment of degenerative spinal conditions and spinal deformity. The TLIF procedure can be performed open or using minimally invasive techniques. While several studies have found that minimally invasive TLIF (MI-TLIF) has advantages over open TLIF procedures with less blood loss, postoperative pain and hospital length of stay, opponents of the minimally invasive technique cite the lack of restoration of lumbar lordosis as a major drawback. With the increasing awareness of restoring sagittal alignment parameters in degenerative and deformity procedures, surgeons should understand the capabilities of different procedures to achieve surgical goals. To our knowledge, few studies have specifically studied the radiographic restoration of lumbar lordosis after MI-TLIF procedures. The purpose of this study was to perform a systematic review of the literature describing the sagittal lumbar radiographic parameter changes after MI-TLIF.

METHODS

Following PRISMA guidelines, systematic review was performed. With the assistance of a medical librarian, a highly-sensitive search strategy formulated on 1/19/2018 utilized the following search terms: "minimally invasive procedures," "transforaminal lumbar interbody fusion," "lumbar interbody fusion," "diagnostic imaging," "radiographs," "radiography," "x-rays," "lordosis," "lumbar vertebrae," "treatment," "outcome," and "lumbosacral" using Boolean operators 'AND' and 'OR'. Three databases were searched (PubMed/Medline, Embase, and Cochrane Library). An online system (www.covidence.org) was used to standardize article review. All studies were independently analyzed by two investigators and discrepancies mitigated by a third reviewer. Study selection for each cycle was Yes/No/Maybe. Cycles were: (1) (Title/Abstract); (2) (Full Text); (3) (Extraction). Inclusion criteria were: (1) All study designs, (2) MI-TLIF procedures, (3) Reporting total lumbar lordosis (LL) and/or segmental lordosis (SL) pre- and postoperatively. Exclusion criteria were: (1) non MI-TLIF procedures (ALIF, XLIF, LLIF, conventional TLIF, OLIF), (2) No reported LL or SL.

RESULTS

The search yielded 4,036 results with 836 duplicates leaving 3,200 studies for review. Cycle 1 eliminated 3,153 studies as irrelevant, thus, 47 were eligible for full-text review. Cycle 2 excluded 31 studies for No English full text (9), Oral/Poster (8), Wrong intervention/outcome (10), Duplicate listing (2), Full text not available (1), Literature review (1) resulting in 16 included studies. Study designs were: Randomized-controlled trial (3), Case series (6) and Retrospective (7). Mean # of subjects were 32.0 (range 8-95). Weighted-mean LL was 39.6°±9.2 (range 28-57) and postoperative LL was 45.0°±7.4 (range 36-67) with a LL post-pre difference of 5.2°±5.9 (range -7 to 15). Weighted-mean preoperative SL was 12.7°±4.3 (range 5-21) and postoperative SL was 15.0°±4.5 (range 5-22) with a SL post-pre difference of 2.1°±1.7 (range 0-8).

CONCLUSIONS

The current literature on MI-TLIF and restoration of LL/SL is limited to 16 published studies, 44% of which are retrospective. The published evidence supporting LL and SL restoration with MI-TLIF is sparse with variable results. This systematic review demonstrates the need for future high-level studies to fully elucidate the capabilities of MI-TLIF procedures for restoring lumbar and segmental lordosis.

Decompression Versus Fusion for Grade I Degenerative Spondylolisthesis: A Meta-Analysis

STUDY DESIGN

Meta-analysis of evidence level I to IV studies.

OBJECTIVE

To compare decompression alone versus decompression plus fusion in the treatment of grade I degenerative spondylolisthesis (DS).

METHODS

Following established guidelines, we systematically reviewed 3 electronic databases to assess studies evaluating patients with grade I DS. We stratified all patients into 2 cohorts; the first cohort underwent a decompression-type surgery, and the second cohort underwent decompression plus fusion. We noted clinical outcomes, complications, reoperations, and surgical details such as blood loss. Descriptive statistics and random-effects models were used to determine the specified outcome metrics with 95% confidence intervals (CIs).

RESULTS

In both cohorts, the pain (legs and lower back) significantly decreased and the physical component of the Short Form 36 showed better patient clinical outcomes. The decompression cohort had a 5.8% complication rate (95% CI = 1.7-2.1), and the decompression plus fusion cohort had an 8.3% complication rate (95% CI = 5.5-11.6). The reoperation rate was higher in the decompression-only cohort (8.5%; 95% CI = 2.9-17.0) compared with the decompression plus fusion cohort (4.9%; 95% CI = 2.5-7.9).

CONCLUSIONS

There does not appear to be any advantage of one procedure over the other. Patients undergoing decompression alone tended to be older with a higher percentage of leg pain, whereas patients additionally undergoing fusion tended to be younger with more lower back pain. The decompression-only cohort had fewer complications but a higher revision rate.

Simultaneous surgical interventions in spinal surgery: a review of the literature and clinical caso for spondylolisthesis of the lumbar spine

The article presents the first clinical case of surgical treatment of a patient with spondylolysis spondylolisthesis using a combination of minimally invasive surgical techniques and simultaneous operation. This intervention has significantly reduced the level of vertebral pain syndrome, improve the functional status in the postoperative period, effectively eliminate pathological mobility, provide early activation, to carry out a full rehabilitation in the shortest possible time and can be an operation of choice in patients with lumbar spondylolysis spondylolisthesis. Conflict of interest: the authors state no conflict ofinterest Funding: the study was performed with no extermal funding