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

A Pharmacogenomics-Based In Silico Investigation of Opioid Prescribing in Post-operative Spine Pain Management and Personalized Therapy

Considering the variability in individual responses to opioids and the growing concerns about opioid addiction, prescribing opioids for postoperative pain management after spine surgery presents significant challenges. Therefore, this study undertook a novel pharmacogenomics-based in silico investigation of FDA-approved opioid medications. The DrugBank database was employed to identify all FDA-approved opioids. Subsequently, the PharmGKB database was utilized to filter through all variant annotations associated with the relevant genes. In addition, the dpSNP ( https://www.ncbi.nlm.nih.gov/snp/ ), a publicly accessible repository, was used. Additional analyses were conducted using STRING-MODEL (version 12), Cytoscape (version 3.10.1), miRTargetLink.2, and NetworkAnalyst (version 3). The study identified 125 target genes of FDA-approved opioids, encompassing 7019 variant annotations. Of these, 3088 annotations were significant and pertained to 78 genes. During variant annotation assessments (VAA), 672 variants remained after filtration. Further in-depth filtration based on variant functions yielded 302 final filtered variants across 56 genes. The Monoamine GPCRs pathway emerged as the most significant signaling pathway. Protein-protein interaction (PPI) analysis revealed a fully connected network comprising 55 genes. Gene-miRNA Interaction (GMI) analysis of these 55 candidate genes identified miR-16-5p as a pivotal miRNA in this network. Protein-Drug Interaction (PDI) assessment showed that multiple drugs, including Ibuprofen, Nicotine, Tramadol, Haloperidol, Ketamine, L-Glutamic Acid, Caffeine, Citalopram, and Naloxone, had more than one interaction. Furthermore, Protein-Chemical Interaction (PCI) analysis highlighted that ABCB1, BCL2, CYP1A2, KCNH2, PTGS2, and DRD2 were key targets of the proposed chemicals. Notably, 10 chemicals, including carbamylhydrazine, tetrahydropalmatine, Terazosin, beta-methylcholine, rubimaillin, and quinelorane, demonstrated dual interactions with the aforementioned target genes. This comprehensive review offers multiple strong, evidence-based in silico findings regarding opioid prescribing in spine pain management, introducing 55 potential genes. The insights from this report can be applied in exome analysis as a pharmacogenomics (PGx) panel for pain susceptibility, facilitating individualized opioid prescribing through genotyping of related variants. The article also points out that African Americans represent an important group that displays a high catabolism of opioids and suggest the need for a personalized therapeutic approach based on genetic information.

The Importance of Planning Ahead: A Three-Dimensional Analysis of the Novel Trans-Facet Corridor for Posterior Lumbar Interbody Fusion Using Segmentation Technology

BACKGROUND

The rise of minimally invasive lumbar fusions and advanced imaging technologies has facilitated the introduction of novel surgical techniques with the trans-facet approach being one of the newest additions. We aimed to quantify any pathology-driven anatomic changes to the trans-facet corridor, which could thereby alter the ideal laterality of approach to the disc space.

METHODS

In this retrospective cohort study, we measured the areas and maximum permissible cannula diameters of the trans-facet corridor using commercially available software (BrainLab, Munich, Germany). Exiting and traversing nerve roots, thecal sacs, and lumbar vertebrae were manually segmented on T2-SPACE magnetic resonance imaging. Spondylolisthesis, disc protrusions, and disc space heights were recorded.

RESULTS

A total of 118 trans-facet corridors were segmented bilaterally in 16 patients (65.6 ± 12.1 years, 43.8% female, body mass index 29.2 ± 5.1 kg/m2). The mean areas at L1-L2, L2-L3, L3-L4, and L4-L5 were 89.4 ± 24.9 mm2, 124 ± 39.4 mm2, 123 ± 26.6 mm2, and 159 ± 42.7 mm2, respectively. The mean permissible cannula diameter at the same levels were 7.85 ± 1.43 mm, 8.98 ± 1.72 mm, 8.93 ± 1.26 mm, and 10.2 ± 1.94 mm, respectively. Both parameters increased caudally. Higher degrees for spondylolisthesis were associated with larger areas and maximum cannula diameters on regression analysis (P < 0.001).

CONCLUSIONS

Our results illustrate that pathology, like spondylolisthesis, can increase the area of the trans-facet corridor. By understanding this effect, surgeons can better decide on the optimal approach to the disc while taking into consideration a patient's unique anatomy.

Outcomes and Complications Associated With the Learning Curve for Endoscopic Cervical Foraminotomy: A Systematic Review and Meta-Analysis

STUDY DESIGN

A systematic review and meta-analysis.

OBJECTIVE

The objective of this study is to examine the impact of the learning curve for endoscopic cervical foraminotomy for clinical outcomes and patient safety.

SUMMARY OF BACKGROUND DATA

Endoscopic cervical foraminotomy is a minimally invasive surgical technique emerging in the literature for surgical management of cervical radiculopathy without the use of open incision. The adoption of endoscopic cervical foraminotomy may be hindered by the learning curve, although no review and meta-analysis exists to date on the topic.

MATERIALS AND METHODS

A systematic review and meta-analysis was performed using PubMed, CINAHL, and MEDLINE from database inception until July 11, 2023. Inclusion criteria were articles that examined endoscopic cervical foraminotomy, reported outcomes, and/or complications for endoscopic cervical spine surgery relevant to the learning curve and had full-text. A random effects meta-analysis was performed for outcomes and complications.

RESULTS

A total of three articles (n=203 patients) were included from 792 articles initially retrieved. The learning curves from four surgeons were examined with a FWM 21 procedures until the competency phase. There was no significant difference in the postoperative hospitalization length ( P =0.669), postoperative recovery room time ( P =0.415), intraoperative blood loss ( P =0.064), and total complication rates (10.9% vs . 1.2%, P =0.139) between endoscopic cervical foraminotomy procedures performed in the learning phase as compared with the competency phase of the learning curve. There was a significant decrease in operative time from the learning phase to the competency phase ( P =0.005).

CONCLUSION

Competency was achieved on the learning curve for endoscopic cervical foraminotomy after about 21 procedures. There is no significant difference in postoperative hospitalization time, postoperative recovery room time, intraoperative blood loss, and complication rates between the learning phase and the competency phase of the learning curve for endoscopic cervical foraminotomy, noting the relatively small sample size of this study that may underpower this finding.

Does Conventional Open TLIF cause more Muscle Injury when Compared to Minimally Invasive TLIF?-A Prospective Single Center Analysis

STUDY DESIGN

Prospective, observational.

OBJECTIVES

The aim of our study was to assess the amount of reduction in lean muscle mass (LMM) of multifidus muscle (MFM) between conventional open Transforaminal lumbar interbody fusion (CO-TLIF) as compared to Minimally invasive spine Transforaminal lumbar interbody fusion (MIS-TLIF).

METHODS

This study was conducted between 2017 and 2020. It included 100 patients divided into two groups, 50 patients treated with CO-TLIF, 50 treated with MIS-TLIF. Only patients undergoing single level, primary lumbar fusion at L4-5 or L5-S1 level for degenerative pathologies were included. All patients were assessed by magnetic resonance imaging (MRI) scans 1-year post surgery. Measurements were performed using ImageJ image processing program.

RESULTS

Mean percentage reduction in LMM in CO-TLIF group was 45.52 ± 12.36% and MIS-TLIF group was 25.83 ± 9.64% [statistically significant (t = 8.78, P < .001)]. Mean percentage reduction in LMM on side of cage insertion was 39.63 ± 15.96% and opposite side was 31.40 ± 15.01% [statistically significant (t = 9.06, P < .001)]. Mean reduction of LMM among males was 29.38 ± 15.23% and females was 40.42 ± 12.67% [statistically significant (t = -3.95, P < .001)].We observed significant but weak degree of correlation between age and percentage reduction of LMM (r = .22, P = .028).

CONCLUSION

Mean reduction in LMM was greater in CO-TLIF group as compared to MIS-TLIF. There was greater reduction in LMM in females and on side of cage insertion. We also found greater reduction in LMM with increasing age in both groups.

Awake Spinal Fusion Is Associated with Reduced Length of Stay, Opioid Use, and Time to Ambulation Compared to General Anesthesia: A Matched Cohort Study

OBJECTIVE

There is increasing interest in performing awake spinal fusion under spinal anesthesia (SA). Evidence supporting SA has been positive, albeit limited. The authors set out to investigate the effects of SA versus general anesthesia (GA) for spinal fusion procedures on length of stay (LOS), opioid use, time to ambulation (TTA), and procedure duration.

METHODS

The authors performed a retrospective review of a single surgeon's patients who underwent lumbar fusions under SA versus GA from June of 2020 to June of 2022. SA patients were compared to demographically matched GA counterparts undergoing comparable procedures. Analyzed outcomes include operative time, opioid usage in morphine milligram equivalents, TTA, and LOS.

RESULTS

Ten SA patients were matched to 10 GA counterparts. The cohort had a mean age of 66.77, a mean body mass index of 27.73 kg/m2, and a median American Society of Anesthesiologists Physical Status Score of 3.00. LOS was lower in SA versus GA patients (12.87 vs. 50.79 hours, P = 0.001). Opioid utilization was reduced in SA versus GA patients (10.76 vs. 31.43 morphine milligram equivalents, P = 0.006). TTA was reduced in SA versus GA patients (7.22 vs. 29.87 hours, P = 0.022). Procedure duration was not significantly reduced in SA patients compared to GA patients (139.3 vs. 188.2 minutes, P = 0.089).

CONCLUSIONS

These preliminary retrospective results suggest the use of SA rather than GA for lumbar fusions is associated with reduced hospital LOS, reduced opioid utilization, and reduced TTA. Future randomized prospective studies are warranted to determine if SA usage truly leads to these beneficial outcomes.

Patient Perceptions of Paramedian Minimally Invasive Spine Skin Incisions

BACKGROUND

In clinical outcome studies, patient input into the factors that drive higher satisfaction with lumbar minimally invasive spinal surgery (MISS) is rare. The skin incision is often the only visible consequence of surgery that patients can assess. The authors were interested in patients' opinions about the type of lumbar paramedian minimally invasive spinal (MIS) skin incision employed during MISS and how novel skin incisions could impact patients' interpretation of the outcome. The authors wanted to compare traditional lumbar stab incisions to three novel lumbar paramedian (MIS) skin incisions to determine if further study is indicated. The primary objective was to examine patient satisfaction and perceptions regarding lumbar paramedian MIS skin incisions.

METHODS

We reviewed the literature and conducted a patient opinion survey. Responses were solicited from back pain patients from a single chiropractic office. Survey questions regarding novel skin incisions for minimally invasive spine surgery (NSIMISS) were conceptualized. The three novel skin incisions were designed using Langer's lines to reduce the total number of incisions; improve patient satisfaction; increase ease of surgical approach/fixation; and reduce operative time/radiation exposure.

RESULTS

One hundred and six participants were surveyed. When shown traditional lumbar paramedian MIS skin stab incisions, 76% of respondents indicated negative responses, n = 65. The majority of patients chose traditional stab incisions (n = 41) followed by novel larger intersecting incisions (n = 37). The least popular incisions were the novel horizontal (n = 20) and the novel mini oblique (n = 5) incisions. Female patients worried more than male patients about how their incision looked. However, there was no statistically significant difference (p value of 0.0418 via Mann-Whitney U one-tailed test and p value of 0.0836 via Mann-Whitney U two-tailed test). Patients less than or equal to 50 years of age worried more than patients over 51 years of age, which was statistically significant (p value of 0.0104 via Mann-Whitney U one-tailed test and p value of 0.0208 via Mann-Whitney U two-tailed test).

CONCLUSIONS

Patients do have opinions on the type of lumbar paramedian MIS skin incision used. It appears that younger patients and female patients worry most about how the incision on their back looks after surgery. A larger population of patients across many demographics is needed to validate these findings.

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

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

Minimally invasive versus open transforaminal lumbar interbody fusion for single segmental lumbar disc herniation: A meta-analysis

BACKGROUND

Numerous studies on the comparison of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and open-transforaminal lumbar interbody fusion (O-TLIF) for the treatment of lumbar disc herniation (LDH) have been published, but there is no clear conclusion.

OBJECTIVE

The aim of this study was to evaluate the efficacy of MIS-TLIF compared with O-TLIF in the treatment of LDH in the Chinese population by meta-analysis.

METHODS

Studies on the treatment of LDH by MIS-TLIF versus O-TLIF were searched in Pubmed, Web of Science, Medline, Embase, CNKI, VIP and China Wanfang databases from the establishment of the databases to January 2020. The meta-analysis was used to analyze the pooled operation time, intraoperative blood loss, postoperative drainage, postoperative ground movement time, Waist and leg Visual Analogue Scale (VAS) score, Oswestry Disability Index (ODI) score and Japanese orthopaedic association (JOA) score. Mean difference (MD) and standard mean difference (SMD) were used as the effect size.

RESULTS

Eleven studies with 1132 patients were included. The results showed that MIS-TLIF compared with O-TLIF, MD =-133.82 (95% CI: -167.10 ∼-100.53, P< 0.05) in intraoperative blood loss, MD =-114.43 (95% CI: -141.12 ∼-87.84, P< 0.05) in postoperative drainage, MD =-3.30 (95% CI: -4.31 ∼-2.28, P< 0.05) in postoperative ground movement time, SMD =-1.44 (95% CI: -2.63 ∼-0.34, P< 0.05) in postoperative low back pain VAS score, SMD = 0.41 (95% CI: 0.15 ∼ 0.66, P< 0.05) in postoperative JOA score, MD = 4.12 (95% CI: -11.64 ∼ 19.87, P> 0.05) in the average operation time, SMD =-0.00 (95% CI: -0.36 ∼ 0.36, P> 0.05) in leg pain VAS score, and SMD =-0.59 (95% CI: -1.22 ∼ 0.03, P> 0.05) in ODI score.

CONCLUSION

MIS-TLIF was superior to O-TLIF in the treatment of LDH, especially in the intraoperative blood loss, postoperative drainage, postoperative ground movement time and low back pain in the Chinese population.

Hybrid revascularization vs. coronary bypass for coronary artery disease: a systematic review and meta-analysis

INTRODUCTION

Coronary artery bypass graft is the mainstay of treatment for multivessel coronary artery disease and is superior to percutaneous coronary intervention. Combined approaches such as hybrid coronary revascularization integrate coronary artery bypass grafting with percutaneous coronary intervention during the same procedure or weeks apart. These attempt to improve surgical morbidity and long-term outcomes.

EVIDENCE ACQUISITION

Per PRISMA criteria, a systematic review of keywords "Hybrid Revascularization," "Hybrid Coronary Revascularization," "Surgical," "Surgery," "Treatment," "CABG," "HCR" and "PCI" was conducted in PubMed, EMBASE and SCOPUS. Studies comparing this technique's performance on either single or two-stage approach against traditional multiple vessel coronary artery bypass grafting were screened and analyzed for our review.

EVIDENCE SYNTHESIS

Twenty-two studies totaling 6981 participants were ultimately included for analysis. Mean differences in operative time, bleeding, ventilator time and length of stay were significantly lower in the hybrid coronary revascularization group. Odds ratios in transfusions and in-hospital myocardial infarction were also lower in the hybrid coronary revascularization group. Results for in-hospital and all-cause mortality, major adverse cardiac events (MACE), stroke, reintervention, and complete revascularization were not significantly different.

CONCLUSIONS

Our analysis shows hybrid coronary revascularization is a feasible alternative to traditional coronary artery bypass grafting. Short-and long-term outcomes including mortality, MACE, and postoperative morbidity are similar between both groups, while hybrid approaches are associated with decreased perioperative morbidity.

A Comparative Study of a New Retractor‐Assisted WILTSE TLIF, MIS‐TLIF, and Traditional PLIF for Treatment of Single‐Level Lumbar Degenerative Diseases

Objectives

To compare the clinical efficacy of a new retractor‐assisted Wiltse transforaminal lumbar interbody fusion (TLIF), minimally invasive TLIF (MIS‐TLIF), and traditional posterior lumbar interbody fusion (PLIF) in treating single‐level lumbar degenerative diseases.

Methods

A retrospective study was conducted by analyzing the clinical and imaging data of consecutive patients with single‐level lumbar degenerative diseases who underwent the new retractor‐assisted Wiltse TLIF, MIS‐TLIF, or traditional PLIF. This study enrolled 87 concurrent patients between June 2016 and December 2019 (Wiltse TLIF 29 cases; MIS‐TLIF 28 cases; PLIF 30 cases). The three groups were compared for perioperative indicators (including intraoperative blood loss, postoperative drainage volume, operation time, intraoperative fluoroscopy time, bedridden time), creatine kinase (CK), visual analog score (VAS), Oswestry disability index (ODI), Japanese Orthopaedic Association (JOA) score, intervertebral fusion rate, muscle atrophy, and fatty infiltration (including ratio of multifidus atrophy and ratio of lean‐to‐total cross‐sectional area [CSA]).

Results

Intraoperative blood loss (F = 62.628, p < 0.001), postoperative drainage volume (F = 72.048, p < 0.001), and bedridden time (χ² = 62.289, p < 0.001) were significantly lower in the MIS‐TLIF and Wiltse groups than in the PLIF group. The operative and intraoperative radiation times of the MIS‐TLIF group were significantly longer than those of the Wiltse and PLIF groups. The CK concentration in the Wiltse and MIS‐TLIF groups were significantly lower than those in the PLIF group 1 day (F = 9.331, p < 0.001) and 3 days after surgery (F = 15.967, p < 0.001). The PLIF group's back pain VAS score was higher than those of the Wiltse and MIS‐TLIF groups. The PLIF group had a higher ODI 6 months (F = 3.282, p = 0.042) and 12 months (F = 5.316, p = 0.007) after surgery and a lower JOA score than the Wiltse and MIS‐TLIF groups 6 months (F = 3.234, p = 0.044) and 12 months (F = 3.874, p = 0.025) after surgery. The ratio of multifidus atrophy in the PLIF group (41.70 ± 8.84%) was significantly higher than those of the Wiltse group (24.13 ± 6.82%) and the MIS‐TLIF group (22.35 ± 5.03%). The ratio of lean‐to‐total CSA in the PLIF group was lower than those of the Wiltse and MIS‐TLIF groups after surgery (F = 8.852, p < 0.001). MIS‐TLIF group showed longer operation time (169.11 ± 29.38 min) and intraoperative fluoroscopy time (87.61 ± 3.13 s) than the Wiltse group.

Conclusion

Wiltse TLIF assisted by the new retractor is a more convenient and minimally invasive surgical method than the traditional PLIF and MIS‐TLIF methods, which are linked to a long learning curve and long operation and fluoroscopy time.

Intraoperative Navigation in Spine Surgery: Effects On Complications and Reoperations

INTRODUCTION

Intraoperative navigation during spine surgery improves pedicle screw placement accuracy. However, limited studies have correlated navigation with clinical factors including operative time and safety. This study compares complications and reoperations between surgeries with and without navigation.

METHODS

Posterior cervical and lumbar fusions and deformity surgeries from 2011-2018 were queried from the NSQIP database and divided by navigation use. Patients aged >89, deformity patients aged <25, and patients undergoing surgery for tumors, fractures, infections, or non-elective indications were excluded. Demographics and perioperative factors were compared with univariate analysis. Outcomes were compared with multivariable logistic regression adjusting for age, sex, BMI, ASA class, surgical region, and multiple levels. Outcomes were also compared stratifying by revision status.

RESULTS

Navigated surgery patients had higher ASA status (p<0.0001), more multiple-level surgeries (p<0.0001), and longer operations (p<0.0001). Adjusted analysis revealed navigated lumbar surgeries had lower odds of complications (OR=0.82, 95%CI=0.77-0.90, p<0.0001), blood transfusion (OR=0.79, 95%CI=0.72-0.87, p<0.0001), and wound debridement/drainage (OR=0.66, 95%CI=0.44-0.97, p=0.04) compared to non-navigated procedures. Navigated cervical fusions had increased odds of transfusion (OR=1.53, 95%CI=1.06-2.23, p=0.02). Navigated primary fusions had decreased odds of complications (OR=0.91, 95%CI=0.85-0.98, p=0.01); no difference was found in revisions (OR=0.89, 95%CI=0.69-1.14, p=0.34).

CONCLUSIONS

Navigated surgery patients experienced longer operations due to a combination of time using navigation, more multi-level procedures and larger comorbidity burden, without differences in infections. There were fewer complications and wound washouts in navigated lumbar surgeries due to a higher percentage of minimally invasive cases. Co-utilization of navigation and minimally invasive surgery may benefit properly indicated patients.

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

STUDY DESIGN

This was a retrospective cohort study.

OBJECTIVE

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

SUMMARY OF BACKGROUND DATA

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Safety of Early Mobilization in Patients With Intraoperative Cerebrospinal Fluid Leak in Minimally Invasive Spine Surgery: A Case Series

BACKGROUND

Cerebrospinal fluid (CSF) leak is a common complication in spine surgery. Repairing durotomy is more difficult in the setting of minimally invasive spine surgery (MISS). Efficacy of postoperative bed rest in case of dural tear in MISS is not clear.

OBJECTIVE

To assess the safety and efficacy of our protocol of dura closure without changing access, early mobilization, and discharge in cases of intraoperative CSF leak in MISS.

METHODS

A retrospective review from 2006 to 2018 of patients who underwent MISS for degenerative and neoplastic diseases with documented accidental or intentional durotomy was conducted. The primary outcome of interest was readmission rate for repair of persistent CSF leak. Secondary outcomes captured included development of pseudomeningocele, positional headache, and subdural hematoma.

RESULTS

A total of 80 patients were identified out of 527 patients. Of these, intentional durotomy was performed in 28 patients and unintentional durotomy occurred in 52 patients. Mean follow-up period was 80.6 mo. Most of the patients were discharged on postoperative day 0 (within 4 h of surgery) without activity restrictions. A total of 2 (2.5%) patients required readmission and dural repair for continuous CSF leak and 3 patients (3.75%) developed pseudomeningocele. No lumbar drain insertion, meningitis, or subdural hematoma was reported.

CONCLUSION

Early mobilization and discharge in cases of intraoperative CSF leak in MISS appear to be safe and not associated with higher rate of complications than that of reported literature.

Opinion Piece: Patient-Specific Implants May Be the Next Big Thing in Spinal Surgery

The emergence of 3D-Printing technologies and subsequent medical applications have allowed for the development of Patient-specific implants (PSIs). There have been increasing reports of PSI application to spinal surgery over the last 5 years, including throughout the spine and to a range of pathologies, though largely for complex cases. Through a number of potential benefits, including improvements to the implant–bone interface and surgical workflow, PSIs aim to improve patient and surgical outcomes, as well as potentially provide new avenues for combating challenges routinely faced by spinal surgeons. However, obstacles to widespread acceptance and routine application include the lack of quality long-term data, research challenges and the practicalities of production and navigating the regulatory environment. While recognition of the significant potential of Spinal PSIs is evident in the literature, it is clear a number of key questions must be answered to inform future clinical and research practices. The spinal surgical community must selectively and ethically continue to offer PSIs to patients, simultaneously allowing for the necessary larger, comparative studies to be conducted, as well as continuing to provide optimal patient care, thereby ultimately determining the exact role of this technology and potentially improving outcomes.

Expandable Versus Static Cages in Minimally Invasive Lumbar Interbody Fusion: A Systematic Review and Meta-Analysis

BACKGROUND

Expandable cages for interbody fusion allow for in situ expansion optimizing fit while mitigating endplate damage. Studies comparing outcomes after using expandable or static cages have been conflicting.

METHODS

This was a meta-analysis A systematic search was performed in accordance with the Preferred Reporting Items for Systemic Reviews and Meta-Analyses (PRISMA) guidelines identifying studies reporting outcomes among patients who underwent minimally invasive lumbar interbody fusion (MIS-LIF).

RESULTS

Fourteen articles with 1129 patients met inclusion criteria. Compared with MIS-LIFs performed with static cages, those with expandable cages had a significantly lower incidence of graft subsidence (expandable: incidence 0.03, I² 22.50%; static: incidence 0.27, I² 51.03%, P interaction <0.001), length of hospital stay (expandable: mean difference [MD] 3.55 days, I² 97%; static: MD 7.1 days, I² 97%, P interaction <0.01), and a greater increase in disc height (expandable: MD -4.41 mm, I² 99.56%; static: MD -0.79 mm, I² 99.17%, P interaction = 0.02). There was no statistically significant difference among Oswestry Disability Index (expandable: MD -22.75, I² 98.17%; static: MD -17.11, I² 95.26%, P interaction = 0.15), fusion rate (expandable: incidence 0.94, I² 0%; static incidence 0.92, I² 0%, P interaction = 0.44), overall change in lumbar lordosis (expandable: MD 3.48 degrees, I² 59.29%; static: MD 3.67 degrees, I² 0.00%, P interaction 0.88), blood loss (expandable: MD 228.9 mL, I² 100%; static: MD 261.1 mL, I² 94%, P interaction = 0.69) and operative time (expandable: MD 184 minutes, I² 95.32%; static: MD 150.4 minutes, I² 91%, P interaction = 0.56).

CONCLUSIONS

Expandable interbody cages in MIS-LIF were associated with a decrease in subsidence rate, operative time and greater in increase in disc height.

Survey of lumbar discectomy practices: 10 years in the making

Background

Lumbar discectomy is a common spinal procedure. The purpose of this survey is to ascertain neurosurgeons' practices in the surgical management of one-level lumbar discectomies in the Canadian adult population and to determine changes over a 10-year period.

Methods

One-page questionnaire distributed electronically to neurosurgeons in Canada and results were compared with similarly completed survey from 2007.

Results

A total of 109 completed surveys were returned representing 43.8% response rate. This is compared to 112 completed surveys in 2007 reaching 64.4% response rate. Statistically significant differences between the two points in time were noted. There was an increase in spine fellowship training [26 (33.3%) 2017 vs. 15 (15.3%) 2007 (P=0.007)], use of pre-operative magnetic resonance imaging (MRI) [65 (83.3%) 2017 vs. 27 (27.6%) 2007] (P<0.001), use of intramuscular injection [58 (74.4%) 2017 vs. 43 (43.9%) 2007 (P<0.001)], use of both microscope and loupes [20 (25.6%) 2017 vs. 3 (3.1%) 2007 (P<0.001)], use of tubular retraction [26 (33.3%) 2017 vs. 12 (12.2%) 2007 (P=0.001)], use of fibrin glue for a durotomy [72 (92.3%) 2017 vs. 75 (76.5%) 2007 (P=0.007)]. There was an increased rate of same-day discharge in 2017 [46 (59.0%) vs. 18 (18.4%) 2007 (P<0.001)], and quicker return to work [62.8% in 6 weeks or less vs. 39.7% (P=0.003)]. No statistical differences were noted with pre-incision localization, pre-op antibiotics, pre-incision local anesthetic use, use of fat graft or epidural steroids. In either survey the majority would not perform lumbar discectomy on a patient whose primary complaint is back pain.

Conclusions

Our survey identified changes in practice patterns amongst Canadian neurosurgeons with respect to performing one-level lumbar discectomy over the past 10 years. These changes include increased preference for minimally invasive surgical technique, same-day discharge and sooner return to work. Randomized trials would be helpful to provide evidence regarding which practices are associated with better outcomes.

The minimally effective dose of bone morphogenetic protein in posterior lumbar interbody fusion: a systematic review and meta-analysis

BACKGROUND CONTENT

The risks and benefits of recombinant human bone morphogenetic protein-2 (BMP) in posterior lumbar interbody fusion (PLIF) and transforaminal lumbar interbody fusion (TLIF) have been widely reported. However, the BMP dose associated with such reports varied widely. Additionally, data on the location of BMP placement on complications and fusion are lacking.

PURPOSE

To determine the minimally effective dose (MED) of BMP which results in optimal fusion rates while minimizing complications; to determine the effects of the location of BMP placement has on fusion rates and complications.

STUDY DESIGN

Systematic review and meta-analysis.

STUDY SAMPLE

Adult patients undergoing PLIF/TLIF for degenerative indications.

OUTCOME MEASURES

Rates of radiculitis, fusion, osteolysis, heterotopic bone formation, and new cancer diagnosis.

METHODS

PubMed, Embase, and Cochrane Database were used to identify studies published between January 1, 2011 and April 30, 2019 reporting BMP usage in adult patients who underwent PLIF/TLIF degenerative indications. A qualitative and quantitative synthesis was performed to evaluate the MED of BMP and the effect of location of BMP placement on fusion and complications. Complications were defined as osteolysis, heterotopic bone growth, radiculitis, and rate of new cancer diagnosis. Complications and fusion outcomes were each pooled according to commercially available BMP doses. Additionally, complications and fusion outcomes were pooled according to 4 location groups (interbody cage only, interbody cage + posterolateral gutter [PLG], cage + interspace, and interspace + PLG). Heterogeneity was assessed with Q and I² statistics.

RESULTS

Twenty-two articles, totaling 2,729 patients were included. Sixteen studies reported fusion and 15 reported complications. Among fusion studies, the mean BMP/level ranged from 1.28 to 12 mg/level. Among complication studies, the mean BMP/level ranged from 6.7 to 23.6 mg/level. The pooled overall fusion rate was 94.0% (91.4-95.8 confidence intervals). There was no significant difference in fusion and complication rates between different BMP doses. Thirteen studies included data on the location of BMP placement with 1,823 patients. At each BMP location, the fusion rate was not significantly different across the dose ranges (1.28-12 mg/level). We found the fusion rate to be marginally higher in the interspace + PLG group compared to the other groups. When BMP was placed in the interbody cage there was a mild increase in the rate of osteolysis compared to other placement locations.

CONCLUSIONS

Fusion and complication rates did not differ significantly between different doses of BMP with the lowest MED for fusion as low as 1.28 mg/level. The location of BMP placement does not significantly affect fusion or complication rates.

Reoperation, Readmission, and Discharge Disposition for Patients With Degenerative Lumbar Pathology Treated With Either Open or Minimally Invasive Techniques: A Single-Center Retrospective Review of 1435 Cases

BACKGROUND

Spine surgery has been transformed by the growth of minimally invasive surgery (MIS) procedures. Previous studies agree that MIS has shorter hospitalization and faster recovery time when compared to conventional open surgery. However, the reoperation and readmission rates between the 2 techniques have yet to be well characterized.

OBJECTIVE

To evaluate the rate of subsequent revision between MIS and open techniques for degenerative lumbar pathology.

METHODS

A total of 1435 adult patients who underwent lumbar spine surgery between 2013 and 2016 were included in this retrospective analysis. The rates of need for subsequent reoperation, 30- and 90-d readmission, and discharge to rehabilitation were recorded for both MIS and traditional open techniques. Groups were divided into decompression alone and decompression with fusion.

RESULTS

The rates of subsequent reoperation following MIS and open surgery were 10.4% and 12.2%, respectively (P = .32), which were maintained when subdivided into decompression and decompression with fusion. MIS and open 30-d readmission rates were 7.9% and 7.2% (P = .67), while 90-d readmission rates were 4.3% and 3.6% (P = .57), respectively. Discharge to rehabilitation was significantly lower for patients under 60 yr of age undergoing MIS (1.64% vs 5.63%, P = .04).

CONCLUSION

The use of minimally invasive techniques for the treatment of lumbar spine pathology does not result in increased reoperation or 30- and 90-d readmission rates when compared to open approaches. Patients under the age of 60 yr undergoing MIS procedures were less likely to be discharged to rehab.

Surgeon motivation, and obstacles to the implementation of minimally invasive spinal surgery techniques

Background

This study aimed to analyze the motivators and obstacles to the implementation of minimally invasive spinal surgery techniques (MISST) by spinal surgeons. Motivators and detractors may impact the availability of MISST to patients and drive spine surgeons' clinical decision-making in the treatment of common degenerative conditions of the lumbar spine.

Methods

The authors solicited responses to an online survey sent to spine surgeons by email, and chat groups in social media networks including Facebook, WeChat, WhatsApp, and Linkedin. Descriptive statistics were employed to count the responses and compared to the surgeon's training. Kappa statistics and linear regression analysis of agreement were performed.

Results

A total of 430 surgeons accessed the survey. The completion rate was 67.4%. A total of 292 surveys were submitted by 99 neurosurgeons (33.9%), 170 orthopaedic surgeons (58.2%), and 23 surgeons of other postgraduate training (7.9%). Personal interest (82.5%) and patient demand (48.6%) were the primary motivators for MISST implementation. High equipment (48.3%) and disposables (29.1%) cost were relevant obstacles to MISST implementation. Local workshops (47.6%) and meetings in small groups (31.8%) were listed as the primary knowledge sources. Only 12% of surgeons were fellowship trained, but 46.3% of surgeons employed MISST in over 25% of their cases.

Conclusions

The rate of implementation of MISST reported by spine surgeons was found to be high but impeded by the high cost of equipment and disposables. The primary motivators for spine surgeons' desire to implement were personal interest and patient demand.

Regional variations in acceptance, and utilization of minimally invasive spinal surgery techniques among spine surgeons: results of a global survey

Background

Regional differences in acceptance and utilization of MISST by spine surgeons may have an impact on clinical decision-making and the surgical treatment of common degenerative conditions of the lumbar spine. The purpose of this study was to analyze the acceptance and utilization of various minimally invasive spinal surgery techniques (MISST) by spinal surgeons the world over.

Methods

The authors solicited responses to an online survey sent to spine surgeons by email, and chat groups in social media networks including Facebook, WeChat, WhatsApp, and Linkedin. Surgeons were asked the following questions: (I) Do you think minimally invasive spinal surgery is considered mainstream in your area and practice setting? (II) Do you perform minimally invasive spinal surgery? (III) What type of MIS spinal surgery do you perform? (IV) If you are performing endoscopic spinal decompression surgeries, which approach do you prefer? The responses were cross-tabulated by surgeons' demographic data, and their practice area using the following five global regions: Africa & Middle East, Asia, Europe, North America, and South America. Pearson Chi-Square measures, Kappa statistics, and linear regression analysis of agreement or disagreement were performed by analyzing the distribution of variances using statistical package SPSS Version 25.0.

Results

A total of 586 surgeons accessed the survey. Analyzing the responses of 292 submitted surveys regional differences in opinion amongst spine surgeons showed that the highest percentage of surgeons in Asia (72.8%) and South America (70.2%) thought that MISST was accepted into mainstream spinal surgery in their practice area (P=0.04) versus North America (62.8%), Europe (52.8%), and Africa & Middle East region (50%). The percentage of spine surgeons employing MISST was much higher per region than the rate of surgeons who thought it was mainstream: Asia (96.7%), Europe (88.9%), South America (88.9%), and Africa & Middle East (87.5%). Surgeons in North America reported the lowest rate of MISST implementation globally (P<0.000). Spinal endoscopy (59.9%) is currently the most commonly employed MISST globally followed by mini-open approaches (55.1%), and tubular retractor systems (41.8%). The most preferred endoscopic approach to the spine is the transforaminal technique (56.2%) followed by interlaminar (41.8%), full endoscopic (35.3%), and over the top MISST (13.7%).

Conclusions

The rate of implementation of MISST into day-to-day clinical practice reported by spine surgeons was universally higher than the perceived acceptance rates of MISST into the mainstream by their peers in their practice area. The survey suggests that endoscopic spinal surgery is now the most commonly performed MISST.

Is Asia truly a hotspot of contemporary minimally invasive and endoscopic spinal surgery?

Background

The purpose of this study was to analyze the training in relation to practice patterns of surgeons in Asia who perform lumbar endoscopic spinal surgery in comparison to surgeons the world over. The authors solicited responses to an online survey sent to spine surgeons.

Methods

Pearson Chi-Square measures, Kappa statistics, and linear regression analysis of agreement or disagreement were performed by analyzing the distribution of variances of responses in relation to surgeons' training using statistical package SPSS Version 25.0.

Results

A total of 430 surgeons accessed the survey. The completion rate was 67.4%. Analyzing the responses of 292 surveys submitted by 97 neurosurgeons (33.2%), 161 orthopaedic surgeons (55.1%), and 34 surgeons of other postgraduate training (11.6%) showed that only 14.0% (41/292) of surgeons had completed a fellowship. Ninety-one of the 292 respondents were from Asian countries/regions. A statistically significantly higher percentage of Asian surgeons (96.7%) compared to non-Asian surgeons (81.6%) indicated that they perform modern minimally invasive (MIS) and endoscopic spinal (ES) surgery (P=0.001). Spinal endoscopy was employed by 70.3% of Asian versus 55.2% of non-Asian surgeons (P=0.015). Endoscopic decompression techniques requiring advanced training was employed nearly twice as high by the Asian surgeons than by non-Asian.

Conclusions

Training requirements for MIS and ES surgery and implementation of privileges vary in different parts of the world. While industry-sponsored weekend cadaver workshops have remained the mainstay of training aspiring endoscopic spinal surgeons in North America and Europe leaving many of them to become autodidacts.

Surgeon training and clinical implementation of spinal endoscopy in routine practice: results of a global survey

Background

Training of spine surgeons may impact the availability of contemporary minimally invasive spinal surgery (MIS) to patients and drive spine surgeons' clinical decision-making when applying minimally invasive spinal surgery techniques (MISST) to the treatment of common degenerative conditions of the lumbar spine. Training requirements and implementation of privileges vary in different parts of the world. The purpose of this study was to analyze the training in relation to practice patterns of surgeons who perform lumbar endoscopic spinal surgery the world over.

Methods

The authors solicited responses to an online survey sent to spine surgeons by email, and chat groups in social media networks including Facebook, WeChat, WhatsApp, and Linkedin. Surgeons were asked the following questions: (I) please indicate your training? (II) What type of MISST spinal surgery do you perform? (III) How would you rate your experience in MIS lumbar spinal surgery and what percentage of your practice is MISST? And (IV) which avenue did you use to train for the MISST you currently employ in your clinical practice today? Descriptive statistics were applied to count responses and cross-tabulated them to the surgeon's training. Pearson Chi-square measures, kappa statistics, and linear regression analysis of agreement or disagreement were performed by analyzing the distribution of variances using statistical package SPSS version 25.0.

Results

A total of 430 surgeons accessed the survey. The completion rate was 67.4%. Analyzing the responses of 292 surveys submitted by 97 neurosurgeons (33.2%), 161 orthopaedic surgeons (55.1%), and 34 surgeons of other postgraduate training (11.6%) showed that only 14% (41/292) of surgeons had completed a fellowship. Surgeons rated their skill level 33.5% of the time as master and experienced surgeon, and 35.6% of the time as novice or surgeon with some experience. There were more master (64.6% versus 29.2%) and experienced (52% versus 40%) surgeons amongst orthopaedic surgeons than amongst neurosurgeons at a statistically significant level (P=0.11). There were near twice as many orthopaedic surgeons (54.3%) using endoscopic procedures in the lumbar spine as their favorite MISST than neurosurgeons (35.4%; P=0.096). Endoscopic spine surgeons' main sources of knowledge acquisition were (I) learning in small meetings (57.3%), (II) attending workshops (63.1%), and (III) national and international conferences (59.8%).

Conclusions

The majority of spine surgeons reported more than half of their cases employing MISST at a high skill level. Very few MISST surgeons are fellowship trained but attend workshops and various meetings suggesting that many of them are self-thought. Orthopaedic surgeons were more likely to implement endoscopic spinal surgery into the routine clinical practice. As endoscopic spine surgery gains more traction and patient demand, minimal adequate training will be part of the ongoing debate.

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.

The Role of the RN Circulator in a Navigated Posterior Spinal Fusion: 1.3 www.aornjournal.org/content/cme

The RN circulator plays a vital role in preparing for a minimally invasive spinal fusion with navigation by confirming that the necessary equipment and stakeholders are available and ensuring that the amount of equipment and the number of people in the room do not compromise patient safety or the sterility of the surgical field. Patients who undergo minimally invasive spinal fusion experience less blood loss, shorter hospital stays, and reduced costs than those who undergo open spinal fusion procedures. The overall successful fusion rates and improvement in patient quality of life are equivalent between the two approaches. Using navigation during minimally invasive and open spinal fusion procedures decreases radiation exposure to the patient and surgical team and helps ensure a more accurate placement of pedicle screws compared with nonnavigated minimally invasive or open spinal fusions.

Endoscopic lumbar discectomy and minimally invasive lumbar interbody fusion: a contrastive review

Both percutaneous endoscopic lumbar discectomy (PELD) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) have been demonstrated as two common and effective choices for lumbar disc herniation (LDH) minimally invasive surgery. In order to get a better understanding of these two procedures, we made this contrastive review. By looking up recent literature and combining it with our clinical practice, the indications/contraindications, advantages/disadvantages as well as complications/recurrences of PELD and MIS-TLIF were summarized in this review. It was concluded that PELD and MIS-TLIF are safe and effective minimally invasive operative techniques for symptomatic LDH treatment. A better understanding of these two procedures will help to improve clinical outcomes by selecting proper indications, and also benefit the further development of minimally invasive spine surgery.