Vascular injury in elective anterior lumbosacral surgery

Anterior Lumbar Interbody Fusion Versus Oblique Lumbar Interbody Fusion Versus Lateral Lumbar Interbody Fusion: Which One in Which Patient?

Anterolateral approaches to the lumbar spine provide direct access to the disc space. These techniques facilitate thorough discectomy, which is essential for successful arthrodesis. They improve segmental lordosis without osteotomy and indirectly decompress neural elements in carefully selected patients. Benefits include shorter operative times, reduced blood loss, and rapid postoperative mobilization compared to posterior approaches. Each technique has specific advantages and limitations, thus none is inherently superior to another. Detailed knowledge of these techniques is essential for modern spine surgeon to provide personalized operative plan for each patient.

Anterior approach for a stab wound with penetrating rebar injury causing incomplete cauda equina syndrome in lumbosacral spine lesion: a case report and literature review

PURPOSE

To report a unique case of incomplete CES following a rebar penetrating injury in perineal region with retro-pulsed fragment, which was treated with anterior approach and discuss suitable surgical approach.

METHODS

Incomplete cauda equina syndrome caused by non-missile penetrating injury is extremely rare. A 26-year-old male patient presented incomplete cauda equina syndrome due to a penetrating rebar wound from his perineal region to the lumbosacral spine. Computed tomography demonstrated a bony fragment broken from S1 body compressing into the spinal canal.

RESULTS

By anterior approach, we performed partial corpectomy of L5, decompression by retrieving the bony fragment and L5-S1 interbody fusion. The patient had a significant recovery, and no clinical complication was found after over 2-year follow-up.

CONCLUSION

It is challenging to determine the optimal strategy of surgical treatment for penetrating spinal injuries with retained foreign bodies, here we suggest an anterior approach situation that has the advantage of being able to effectively perform decompression and prevent iatrogenic damages of thecal sac and nerve rootlets.

Single Position Lateral versus Prone Transpsoas Lateral Interbody Fusion Inclusive of L4-L5: A Single Surgeon Experience Examining Early Postoperative Outcomes

OBJECTIVE

The transpsoas lateral lumbar interbody fusion (LLIF) procedure is a minimally invasive lumbar spine approach that provides indirect neural decompression, improved sagittal alignment, and a high fusion rate. Typically accompanied by posterior pedicle screw insertion, there has been interest in performing LLIF in a single position to decrease cost and time under anesthesia. However, there is a paucity of direct comparisons between single-position LLIF via prone versus lateral decubitus positioning. Therefore, this study aims to compare the outcomes of a single surgeon performing prone versus lateral single-position LLIF, inclusive of the L4-L5 level.

METHODS

A retrospective review was performed of a consecutive case series of patients who underwent either prone or lateral, single-position LLIF by a single surgeon. All cases involved the L4-L5 level. Demographic data, perioperative details, clinical outcomes, and preoperative and postoperative lumbar lordosis were recorded.

RESULTS

Sixty-three patients underwent lateral and 16 patients underwent prone single-position LLIF. Demographics and average interbody size were similar between groups. Operative time, change in lumbar lordosis, and length of hospital stay did not differ between the 2 positions. Both groups performed similarly in terms of preoperative and postoperative visual analog score pain score and complications. Patients who underwent lateral position LLIF ambulated farther on postoperative day 1 (250 feet vs. 200 feet, P = 0.015). Average time to follow up was 53 weeks.

CONCLUSIONS

This study demonstrates promising preliminary results indicating that single-position LLIF performs well, even at the L4-L5 level, in both the prone and lateral positions.

A novel surgical approach using the "lateral corridor" for minimally invasive oblique lumbar interbody fusion at L5-S1: a clinical series and technical note

PURPOSE

The minimally invasive oblique lumbar interbody fusion (MI-OLIF) L5-S1 was introduced to overcome the limitations of conventional fusion techniques, however, MI-OLIF is not possible using the standard method due to vascular structures in some cases. We aimed to introduce the "lateral corridor" and report the details of the surgical technique with a clinical case series.

METHODS

We utilized the lateral access route of the left common iliac vein and named it the "lateral corridor", to distinguish the technique from the standard technique (central corridor). The type and frequency of branch vessels that required additional manipulations were reviewed, and the frequency of intraoperative vascular injury was investigated.

RESULTS

Among the 107 patients who underwent MI-OLIF L5-S1, 26 patients (24.3%) who received the "lateral corridor" technique were included. Branch vessel ligation was required in 42.3% of the patients. The types of branch vessels that required ligation were seven cases (26.9%) of the iliolumbar vein (ILV) and six cases (23.1%) of ascending lumbar vein (ALV). The ILV and ALV were ligated in two cases. None of the patients developed intraoperative vascular injuries.

CONCLUSION

We introduced the "lateral corridor" as an alternative approach for MI-OLIF L5-S1, implemented it in 24.3% of the patient cohort, and reported favorable outcomes devoid of vascular complications. The "lateral corridor" necessitated ligation of the ILV or ALV in 42.3% of cases. The "lateral corridor" approach appears to be a promising surgical technique, offering feasibility even in instances where the vascular anatomy precludes the employment of the conventional approach.

Risk Factors for Subsidence Following Anterior Lumbar Interbody Fusion

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

Anterior lumbar interbody fusion (ALIF) may be complicated by subsidence, which can lead to significant morbidity including pain, disc space collapse, neural compression, segmental kyphosis, instability, and vertebral body fracture. This study sought to identify patient and procedural risk factors for subsidence in patients undergoing ALIF.

METHODS

This study analyzed consecutive patients who underwent ALIF at a single institution with a minimum of 2 years follow-up. Patients were grouped as either Non-Subsidence (NS-ALIF) or Cage Subsidence (CS-ALIF) based on the final postoperative radiograph. Demographic variables, operative characteristics, and radiographic outcomes were evaluated to identify significant predictors on univariate and multivariate statistics.

RESULTS

144 patients (170 levels) were included with an average follow-up of 50.70 ± 28.44 months (4.23 years). The incidence of subsidence was 22.94% (39/170 levels). On univariate statistics, the CS-ALIF group was significantly older (P = .020), had higher BMI (P = .048), worse ASA (P = .001), higher prevalence of comorbid osteoporosis (P < .001), and a more anteriorly placed interbody device (P = .005). On multivariate analysis, anterior cage placement remained the only significant predictor (OR: 1.08, 95% CI: 1.03-1.14; P = .003). There was a significantly higher rate of subsequent adjacent segment surgery among the CS-ALIF group (P = .035).

CONCLUSION

Factors contributing to subsidence in ALIF included older age, higher BMI, severe ASA, and osteoporosis, while anterior cage placement remained the only independent predictor on multivariate analysis. Subsidence was associated with a higher rate of subsequent adjacent segment surgery. Surgical technique should optimize placement of the interbody cage and avoid overstuffing the disc space.

Risk Factors for Postoperative Urinary Retention After Lumbar Fusion Surgery: Anesthetics and Surgical Approach

INTRODUCTION

Postoperative urinary retention (POUR) after lumbar fusion surgery can lead to longer hospital stays and thus increased risk of developing other postoperative complications. Therefore, we aimed to determine the relationship between POUR and (1) surgical approach and (2) anesthetic agents, including sugammadex and glycopyrrolate.

METHODS

After institutional review board approval, L4-S1 single-level lumbar fusion surgeries between 2018 and 2021 were identified. A 3:1 propensity match of patients with POUR to those without was conducted, controlling for patient age, sex, diabetes status, body mass index, smoking status, history of benign prostatic hyperplasia, and the number of levels decompressed. POUR was defined as documented straight catheterization yielding >400 mL. We compared patient demographic, surgical, anesthetic, and postoperative characteristics. A bivariant analysis and backward multivariable stepwise logistic regression analysis ( P -value < 0.200) were performed. Significance was set to P < 0.05.

RESULTS

Of the 899 patients identified, 51 met the criteria for POUR and were matched to 153 patients. No notable differences were observed between groups based on demographic or surgical characteristics. On bivariant analysis, patients who developed POUR were more likely to have been given succinylcholine (13.7% vs. 3.92%, P = 0.020) as an induction agent. The independent predictors of POUR identified by multivariable analysis included the use of succinylcholine {odds ratio (OR), 4.37 (confidence interval [CI], 1.26 to 16.46), P = 0.022} and reduced postoperative activity (OR, 0.99 [CI, 0.993 to 0.999], P = 0.049). Factors protective against POUR included using sugammadex as a reversal agent (OR, 0.38 [CI, 0.17 to 0.82], P = 0.017). The stepwise regression did not identify an anterior surgical approach as a notable predictor of POUR.

CONCLUSION

We demonstrate that sugammadex for anesthesia reversal was protective against POUR while succinylcholine and reduced postoperative activity were associated with the development of POUR. In addition, we found no difference between the anterior or posterior approach to spinal fusion in the development of POUR.

Stand-alone ALIF versus TLIF in patients with low back pain - A propensity-matched cohort study with two-year follow-up

Introduction

Instrumented lumbar fusion by either the anterior or transforaminal approach has different advantages and disadvantages. Few studies have compared PatientReported Outcomes Measures (PROMs) between stand-alone anterior lumbar interbody fusion (SA-ALIF) and transforaminal lumbar interbody fusion (TLIF).

Research question

This is a register-based dual-center study on patients with severe disc degeneration (DD) and low back pain (LBP) undergoing single-level SA-ALIF or TLIF. Comparing PROMs, including disability, quality of life, back- and leg-pain and patient satisfaction two years after SA-ALIF or TLIF, respectively.

Material and methods

Data were collected preoperatively and at one and two-year follow-up. The primary outcome was Oswestry Disability Index (ODI). The secondary outcomes were patient satisfaction, walking ability, visual analog scale (VAS) scores for back and leg pain, and quality of life (QoL) measured by the European Quality of Life-5 Dimensions (EQ-5D) index score. To reduce baseline differences between groups, propensity-score matching was employed in a 1:1 fashion.

Results

92 patients were matched, 46 S A-ALIF and 46 TLIF. They were comparable preoperatively, with no significant difference in demographic data or PROMs (P > 0.10). Both groups obtained statistically significant improvement in the ODI, QoL and VAS-score (P < 0.01), but no significant difference was observed (P = 0.14). No statistically significant differences in EQ-5D index scores (P = 0.25), VAS score for leg pain (P = 0.88) and back pain (P = 0.37) at two years follow-up.

Conclusion

Significant improvements in ODI, VAS-scores for back and leg pain, and EQ-5D index score were registered after two-year follow-up with both SA-ALIF and TLIF. No significant differences in improvement.

Anterior Lumbar Interbody Fusion in Elderly Patients: Peri- and Postoperative Complications and Clinical Outcome

BACKGROUND

 Anterior lumbar interbody fusion (ALIF) is an effective surgical technique for treating various lumbar pathologies, but its use in elderly patients is controversial. Data concerning complications and effectiveness are sparse. We investigated peri- and postoperative complications, radiographic parameters, and clinical outcome in elderly patients.

METHODS

 Patients ≥65 years who underwent ALIF between January 2008 and August 2020 were included in the study. All surgeries were performed through a retroperitoneal approach. Clinical and surgical data as well as radiologic parameters were collected prospectively and analyzed retrospectively.

RESULTS

 A total of 39 patients were included; the mean age was 72.6 (±6.3) years (range: 65-90 years); and the mean American Society of Anesthesiologists (ASA) risk classification was 2.3 (±0.6). A laceration of the left common iliac vein was the only major complication recorded (2.6%). Minor complications occurred in 20.5% of patients. Fusion rate was 90.9%. Reoperation rate at the index level was 12.8 and 7.7% in adjacent segments. The multidimensional Core Outcome Measures Index (COMI) improved from 7.4 (±1.4) to 3.9 (±2.7) after 1 year and to 3.3 (±2.6) after 2 years. Oswestry disability index (ODI) improved from 41.2 (±13.7) to 20.9 (±14.9) after 1 year and to 21.5 (±18.8) after 2 years. Improvements of at least the minimal clinically important change score of 2.2 and 12.9 points in the ODI and COMI after 2 years were noted in 75 and 56.3% of the patients, respectively.

CONCLUSION

 With careful patient selection, ALIF is safe and effective in elderly patients.

Lateral interbody fusion without intraoperative neuromonitoring in addition to posterior instrumented fusion in geriatric patients: A single center consecutive series of 108 surgeries

Introduction

Lateral lumbar interbody fusion (LLIF) and lateral thoracic interbody fusion (LTIF), supported by intraoperative neuromonitoring (IONM), gained popularity as a mini-invasive alternatives for standard interbody fusion. The objective of this study was to investigate the clinical outcome in a large elderly patient cohort who underwent LTIF/LLIF without IONM.

Methods

This retrospective, single-center study enrolled elderly patients (≥70 years old) operated during the period from 2010 to 2016. Anterior lumbar interbody fusion (ALIF) in the L5/S1 segment was excluded from the analysis.

Results

The study enrolled 108 patients (63 males, 58.3%) with a mean age of 76.5 ​y/o. The mean follow-up was 14.4 ​± ​11.3 months. The mean time of the surgery was 92 ​± ​34.2 ​min. The mean blood loss was 62.2 ​ml. There were no vascular or visceral surgical complications. 39 medical complications were encountered in 24 (22%) patients. Less than 5% of patients presented with a new onset of motor weakness and less than 2% of the patients developed a new sensory deficit at the discharge. 46% of patients were lost in follow-up at 12 months.

Conclusions

IONM is not mandatory for LLIF/LTIF surgery in geriatric patients and has a low frequency of approach-related complications as well as neurological deterioration. Our results are comparable to the available literature. Regardless of the utilization of these mini-invasive, anterior approaches, in patients of advanced aged, the risk for major medical complications is high and is responsible for contributing to prolonged hospitalization.

Multilevel tandem spondylolisthesis associated with a reduced "safe zone" for a transpsoas lateral lumbar interbody fusion at L4-5

OBJECTIVE

The aim of this study was to investigate the effect of degenerative spondylolisthesis (DS) on psoas anatomy and the L4-5 safe zone during lateral lumbar interbody fusion (LLIF).

METHODS

In this retrospective, single-institution analysis, patients managed for low-back pain between 2016 and 2021 were identified. Inclusion criteria were adequate lumbar MR images and radiographs. Exclusion criteria were spine trauma, infection, metastases, transitional anatomy, or prior surgery. There were three age and sex propensity-matched cohorts: 1) controls without DS; 2) patients with single-level DS (SLDS); and 3) patients with multilevel, tandem DS (TDS). Axial T2-weighted MRI was used to measure the apical (ventral) and central positions of the psoas relative to the posterior tangent line at the L4-5 disc. Lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), and PI-LL mismatch were measured on lumbar radiographs. The primary outcomes were apical and central psoas positions at L4-5, which were calculated using stepwise multivariate linear regression including demographics, spinopelvic parameters, and degree of DS. Secondary outcomes were associations between single- and multilevel DS and spinopelvic parameters, which were calculated using one-way ANOVA with Bonferroni correction for between-group comparisons.

RESULTS

A total of 230 patients (92 without DS, 92 with SLDS, and 46 with TDS) were included. The mean age was 68.0 ± 8.9 years, and 185 patients (80.4%) were female. The mean BMI was 31.0 ± 7.1, and the mean age-adjusted Charlson Comorbidity Index (aCCI) was 4.2 ± 1.8. Age, BMI, sex, and aCCI were similar between the groups. Each increased grade of DS (no DS to SLDS to TDS) was associated with significantly increased PI (p < 0.05 for all relationships). PT, PI-LL mismatch, center psoas, and apical position were all significantly greater in the TDS group than in the no-DS and SLDS groups (p < 0.05). DS severity was independently associated with 2.4-mm (95% CI 1.1-3.8 mm) center and 2.6-mm (95% CI 1.2-3.9 mm) apical psoas anterior displacement per increased grade (increasing from no DS to SLDS to TDS).

CONCLUSIONS

TDS represents more severe sagittal malalignment (PI-LL mismatch), pelvic compensation (PT), and changes in the psoas major muscle compared with no DS, and SLDS and is a risk factor for lumbar plexus injury during L4-5 LLIF due to a smaller safe zone.

Anterior Longitudinal Ligament Flap Technique: Description of Anterior Longitudinal Ligament Opening During Anterior Lumbar Spine Surgery and Review of Vascular Complications in 189 Patients

BACKGROUND

One of the main concerns of anterior lumbar spine approaches are vascular complications. The aim of our study is to provide technical details about a flap technique using the anterior longitudinal ligament (ALL) when approaching the lumbar spine via an anterior corridor. This can help decrease complications by protecting the adjacent vascular structures. We also include a retrospective cohort review.

METHODS

This is a retrospective bicentric study: 189 patients with a mean age of 44.2 years underwent anterior lumbar spine surgery using the ALL flap technique. Patients were diagnosed with degenerative pathologies. We treated 239 lumbar levels primarily at the L4-5 and L5-S1: 88 single-level anterior lumbar interbody fusions, 9 two-level ALIFs, 51 total disk replacements (TDR), and 41 hybrid constructs (i.e., ALIF L5S1 and TDR L4L5). Anterior approaches were performed by two senior spine surgeons. The ALL flap technique was utilized in all of these cases, by carefully dissecting the ALL, with the flap suspended using sutures. As such, this ALL flap provided a "safe corridor" to avoid any potential vascular laceration.

RESULTS

The operative and early surgical complication rate was 3.2%. There was no arterial injury. There were only 2 minor venous lacerations (1.05%). No blood transfusion was required. Neither lacerations happened during disk space preparation.

CONCLUSIONS

Here, we provide technical details about a simple and reproducible technique using the ALL as a flap, which may help spine surgeons minimize vascular injuries during ALIF or even TDR surgeries.

Pediatric surgical errors: A systematic scoping review

BACKGROUND

Medical errors were largely concealed prior to the landmark report "To Err Is Human". The purpose of this systematic scoping review was to determine the extent pediatric surgery defines and studies errors, and to explore themes among papers focused on errors in pediatric surgery.

METHODS

The methodological framework used to conduct this scoping study has been outlined by Arksey and O'Malley. In January 2020, PubMed, the Cochrane Database of Systematic Reviews, and the Cochrane Central Register of Controlled Trials were searched. Oxford Level of Evidence was assigned to each study; only studies rated Level 3 or higher were included.

RESULTS

Of 3,064 initial studies, 12 were included in the final analysis: 4 cohort studies, and 8 outcome/audit studies. This data represented 5,442,000 aggregate patients and 8,893 errors. There were 6 different error definitions and 5 study methods. Common themes amongst the studies included a systems-focused approach, an increase in errors seen with increased complexity, and studies exploring the relationship between error and adverse events.

CONCLUSIONS

This study revealed multiple error definitions, multiple error study methods, and common themes described in the pediatric surgical literature. Opportunities exist to improve the safety of surgical care of children by reducing errors. Original Scientific Research Type of Study: Systematic Scoping Review Level of Evidence Rating: 1.

Risk Factors for Venous Thrombosis after Spinal Surgery: A Systematic Review and Meta-analysis

Background. Venous thrombosis, comprising DVT and PE, is an orthopedic condition that may be fatal after surgery. This study’s purpose was to analyze risk factors for venous thrombosis following spine surgery to help guide treatment prophylaxis. Methods. A computer searched English databases such as PubMed, Web of Science, Embase, Cochrane Library, and Google Academic for relevant publications after spinal surgery. Preoperative walking difficulties, hypertension, diabetes, heart disease, preoperative bleeding volume, etc., were all examined using the NOS scale. Data were analyzed using Review Manager 5.3 software. An analysis was done. Due to the study’s differences, the data was compiled using fixed effects or random effects models. Results. A total of 25 studies were considered, with a total of 1,927,781 individuals after spine surgery, including 7843 patients with venous thrombosis. The included literatures had NOS scores ranging from 5 to 8. According to the findings of the meta-analysis, the age of patients with venous thrombosis after spinal surgery ( $\text{OR}=7.53$ , 95% CI (6.73, 8.33)), blood loss ( $\text{OR}=-141.79$ , 95% CI (-154.68, -128.9), $P=0.00001$ ), and operation time ( $\text{OR}=76.93$ , 95% CI (73.17, 80.86), $P=0.00001$ ) were higher than those without; diabetes mellitus (OR =1.23, 95% CI (1.12, 1.34), $P=0.00001$ ) and walking disability history ( $\text{OR}=2.97$ , 95% CL (1.77, 4.98), $P=0.0001$ ) increased the incidence of postoperative venous thrombosis. Conclusion. High age, female, spinal fusion, big volume blood loss patients, operation time, and hypertension, diabetes, and walking issue are all risk factors for venous thrombosis following surgery.

Defining and Studying Errors in Surgical Care: A Systematic Review

OBJECTIVE

Our objective was to determine the extent surgical disciplines categorize, define, and study errors, then use this information to provide recommendations for both current practice and future study.

SUMMARY BACKGROUND DATA

The report "To Err is Human" brought the ubiquity of medical errors to public attention. Variability in subsequent literature suggests the true prevalence of error remains unknown.

METHODS

In January 2020, PubMed, the Cochrane Database of Systematic Reviews, and the Cochrane Central Register of Controlled Trials were searched. Only studies with Oxford Level of Evidence Level 3 or higher were included.

RESULTS

Of 3,064 studies, 92 met inclusion criteria: 6 randomized controlled trials, 4 systematic reviews, 24 cohort, 10 before-after, 35 outcome/audit, 5 cross sectional and 8 case-control studies. Over 15,933,430 patients and 162,113 errors were represented. There were 6 broad error categories, 13 different definitions of error, and 14 study methods.

CONCLUSIONS

Reported prevalence of error varied widely due to a lack of standardized categorization, definitions, and study methods. Future research should focus on immediately recognizing errors to minimize harm.

Vascular Injury in Elective Anterior Surgery of the Lumbar Spine: A Narrative Review

The incidence of anterior lumbar surgery is increasing as the population is aging. Although adverse events regarding vasculature injury are uncommon, several have been described in the current literature. Complications can be categorized based on the time of occurrence, more specifically intraoperative or postoperative, but also regarding the nature of vascular damage such as thrombosis, occlusion, or rupture. The rate of complications is higher in the setting of revision anterior surgery than with primary anterior lumbar surgery. Moreover, the incidence of revision anterior surgery is also increasing in contrast to the past. Through this narrative review, an effort is made for a thorough understanding of the complications associated with anterior lumbar surgery, which will aid in the prevention, recognition, and management of this rare complication.

Revisiting anterior longitudinal ligament release: Are we ready for an endoscopic approach?

Anterior longitudinal ligament release is a proven method for restoring spinopelvic parameters. This technique is mostly described using either lateral or anterior approaches with paucity regarding a posterior method. This paper is the first to provide descriptive analysis of the neurovascular anatomy in the context of planning for a posterior endoscopic ALL release. A retrospective chart review was performed on patients underwent any lumbar surgery by a single surgeon. Anatomical data was obtained from pre-operative CT to describe the location of key neurovascular structures in relation to the ALL with focus on posterior approach. A total of 20 patients were included in data analysis. A posterior approach with endoscopic assistance would be feasible at L4/5 and L5/S1, where the bifurcation of the abdominal aorta has occurred with a vessel window that ranges from 18.85 mm to 33.45 mm with at least 2 mm space between the vessels and the corresponding disc spaces in the anterior-posterior dimension with slight predilection of the left side at the L5/S1 level to avoid any neurovascular structures. Our study confirmed the findings of previous studies examining the vascular anatomy associated with the lumbar spine. Interestingly, we found that direct midline would likely not be the best location for a posterior annulotomy, and that both the window between the iliac vessels as well as the distance in AP dimension between the spine and vessels increases as you descend the lumbar spine. This information will help guide future efforts to fully develop a safe and reproducible posterior endoscopic ALL release.

Is there a variance in complication types associated with ALIF approaches? A systematic review

Purpose

Anterior lumbar interbody fusion (ALIF) is a well-established alternative to posterior-based interbody fusion techniques, with approach variations, such as retroperitoneal, transperitoneal, open, and laparoscopic well described. Variable rates of complications for each approach have been enumerated in the literature. The purpose of this study was to elucidate the comparative rates of complications across approach type.

Methods

A systematic review of search databases PubMed, Google Scholar, and OVID Medline was made to identify studies related to complication-associated ALIF. PRISMA guidelines were utilised for this review. Meta-analysis was used to compare intraoperative and postoperative complications with ALIF for each approach.

Results

A total of 4575 studies were identified, with 5728 patients across 31 studies included for review following application of inclusion and exclusion criteria. Meta-analysis demonstrated the transperitoneal approach resulted in higher rates of retrograde ejaculation (RE) (p < 0.001; CI = 0.05–0.21) and overall rates of complications (p = 0.05; CI = 0.00–0.23). Rates of RE were higher at the L5/S1 intervertebral level. Rates of vessel injury were not significantly higher in either approach method (p = 0.89; CI =  − 0.04–0.07). Rates of visceral injury did not appear to be related to approach method. Laparoscopic approaches resulted in shorter inpatient stays (p = 0.01).

Conclusion

Despite the transperitoneal approach being comparatively underpowered, its use appears to result in a significantly higher rate of intraoperative and postoperative complications, although confounders including use of bone morphogenetic protein (BMP) and spinal level should be considered. Laparoscopic approaches resulted in shorter hospital stays; however, its steep learning curve and longer operative time have deterred surgeons from its widespread adaptation.

Development of machine learning and natural language processing algorithms for preoperative prediction and automated identification of intraoperative vascular injury in anterior lumbar spine surgery

BACKGROUND

Intraoperative vascular injury (VI) may be an unavoidable complication of anterior lumbar spine surgery; however, vascular injury has implications for quality and safety reporting as this intraoperative complication may result in serious bleeding, thrombosis, and postoperative stricture.

PURPOSE

The purpose of this study was to (1) develop machine learning algorithms for preoperative prediction of VI and (2) develop natural language processing (NLP) algorithms for automated surveillance of intraoperative VI from free-text operative notes.

PATIENT SAMPLE

Adult patients, 18 years or age or older, undergoing anterior lumbar spine surgery at two academic and three community medical centers were included in this analysis.

OUTCOME MEASURES

The primary outcome was unintended VI during anterior lumbar spine surgery.

METHODS

Manual review of free-text operative notes was used to identify patients who had unintended VI. The available population was split into training and testing cohorts. Five machine learning algorithms were developed for preoperative prediction of VI. An NLP algorithm was trained for automated detection of intraoperative VI from free-text operative notes. Performance of the NLP algorithm was compared to current procedural terminology and international classification of diseases codes.

RESULTS

In all, 1035 patients underwent anterior lumbar spine surgery and the rate of intraoperative VI was 7.2% (n=75). Variables used for preoperative prediction of VI were age, male sex, body mass index, diabetes, L4-L5 exposure, and surgery for infection (discitis, osteomyelitis). The best performing machine learning algorithm achieved c-statistic of 0.73 for preoperative prediction of VI (https://sorg-apps.shinyapps.io/lumbar_vascular_injury/). For automated detection of intraoperative VI from free-text notes, the NLP algorithm achieved c-statistic of 0.92. The NLP algorithm identified 18 of the 21 patients (sensitivity 0.86) who had a VI whereas current procedural terminologyand international classification of diseases codes identified 6 of the 21 (sensitivity 0.29) patients. At this threshold, the NLP algorithm had a specificity of 0.93, negative predictive value of 0.99, positive predictive value of 0.51, and F1-score of 0.64.

CONCLUSION

Relying on administrative procedural and diagnosis codes may underestimate the rate of unintended intraoperative VI in anterior lumbar spine surgery. External and prospective validation of the algorithms presented here may improve quality and safety reporting.

Identifying Risk Factors for Complications During Exposure for Anterior Lumbar Interbody Fusion

Introduction

An anterior approach to lumbar interbody fusion is a widely utilized method of access to the lumbar spine. Due to the potential for vascular complications with spine exposure, vascular surgeons are frequently included in the care of these patients as part of a team-based approach. Identifying risk factors for such complications is difficult and not well-defined in the literature. In this investigation, we evaluate the potential risk factors for complications during anterior lumbar inter-body fusion (ALIF).

Methods

This is a retrospective review of 106 patients who underwent ALIF at a single institution between May 1, 2007, and April 30, 2017. Patients were identified through operating room case logs and Current Procedural Terminology (CPT) codes correlating with ALIF. Vascular surgeons performed all anterior exposures. Patient demographics and data regarding their surgical care and postoperative course were obtained from a review of operative and progress notes in the electronic medical record. Statistical methods employed included a t-test for normally distributed data and the Wilcoxon rank-sum test for non-normally distributed data. Categorical variables were compared using Fisher’s exact and chi-square tests. A logistic regression model was applied to predict complications by controlling other significant covariates.

Results

Of the 106 patients included in this analysis, 16 patients experienced a defined complication, giving an overall complication rate of 15%. Patients with complications were more likely to be of male gender (n=11, P=0.016), with older average age (54.6, P=0.017), with higher estimated blood loss, with higher use of blood products, and with higher use of cell-saver. A venous injury was the most common complication (n=11, 10.4%); ileus and nerve injury were the next most common (n=3, 2.8%). The 30-day mortality was 0%. Male gender demonstrated an odds ratio of 3.78 (P=0 .034) in a logistic regression model after adjusting for age and blood products.

Conclusions

Overall complication rates were comparable to those in the published literature and male gender was identified as a predictor for risk of complications in those undergoing ALIF. This is the first study to identify male sex as a risk factor for complications following ALIF. The results of this study will hopefully guide future studies in gaining more insight into the predictors of complications in larger series.

Efficacy and radiographic analysis of oblique lumbar interbody fusion in treating adult spinal deformity

Adult spinal deformity (ASD) is usually rigid and requires a combined anterior–posterior approach for deformity correction. Anterior lumbar interbody fusion (ALIF) allows direct access to the disc space and placement of a large interbody graft. A larger interbody graft facilitates correction of ASD. However, an anterior approach carries significant risks. Lateral lumbar interbody fusion (LLIF) through a minimally invasive approach has recently been used for ASD. The present study was performed to evaluate the effectiveness of oblique lumbar interbody fusion (OLIF) in the treatment of ASD. We performed a retrospective study utilizing the data of 74 patients with ASD. The inclusion criteria were lumbar coronal Cobb angle > 20°, pelvic incidence (PI)–lumbar lordosis (LL) mismatch > 10°, and minimum follow–up of 2 years. Patients were divided into two groups: ALIF combined with posterior spinal fixation (ALIF+PSF) (n = 38) and OLIF combined with posterior spinal fixation (OLIF+PSF) (n = 36). The perioperative spinal deformity radiographic parameters, complications, and health-related quality of life (HRQoL) outcomes were assessed and compared between the two groups. The preoperative sagittal vertical axis (SVA), LL, PI–LL mismatch, and lumbar Cobb angles were similar between the two groups. Patients in the OLIF+PSF group had a slightly higher mean number of interbody fusion levels than those in the ALIF+PSF group. At the final follow–up, all radiographic parameters and HRQoL scores were similar between the two groups. However, the rates of perioperative complications were higher in the ALIF+PSF than OLIF+PSF group. The ALIF+PSF and OLIF+PSF groups showed similar radiographic and HRQoL outcomes. These observations suggest that OLIF is a safe and reliable surgical treatment option for ASD.

Late diagnosis of ureteral injury from anterior lumbar spine interbody fusion surgery: Case report and literature review

BACKGROUND

Anterior Lumbosacral Interbody Fusion (ALIF) is a type of back surgery with the advantages of direct access to the spinal interbody space and the potential lessening morbidity related to posterior approaches.

PURPOSE

To describe a rare case of left ureteral lesion from ALIF surgery diagnosed 4 months after the procedure.

CASE DESCRIPTION

A 37-year-old Caucasian man with a long history of painful post-traumatic spondylolisthesis and degenerative L5-S1 disc disease underwent a retroperitoneal anterior L5-S1 discectomy, insertion of an interbody tantallium cage, and placement of a pyramid titanium plate fixed with screws. Four months later, due to recurrent left lumbar pain and mild renal failure, a CT scan was performed showing left hydronephrosis with a homolateral urinoma of 17 cm in diameter. A left nephrostomy was placed and the nephrostography detected a filiform leakage at L5-S1 level in communication with the urinoma. The patient underwent laparoscopic urinoma drainage, distal left ureterectomy, and Casati-Boari flap ureterocystoneostomy with ureteral double J stent placement. The stent was held for six weeks and, 1 month later, the control ultrasound scan was negative for hydronephrosis, the creatinine level had normalized and the patient was asymptomatic.

CONCLUSION

Ureteral lesion from ALIF surgery is a very rare event. Spinal surgeons should be more awareness regarding the susceptibility of ureteral injuries along with the clinical presentation, diagnostic work-up, and management options for this kind of complication.

Does L5-S1 Anterior Lumbar Interbody Fusion Improve Sagittal Alignment or Fusion Rates in Long Segment Fusion for Adult Spinal Deformity?

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

To assess whether the addition of L5-S1 anterior lumbar interbody fusion (ALIF) improves global sagittal alignment and fusion rates in patients undergoing multilevel spinal deformity surgery.

METHODS

Two-year radiographic outcomes, including lumbar lordosis, pelvic incidence, pelvic tilt, and T1 pelvic angle; hardware complications; and nonunion/pseudarthrosis rates were compared between patients who underwent lumbosacral fusion at 4 or more vertebral levels with and without L5-S1 ALIF between November 2003 and September 2016.

RESULTS

A total of 51 patients who underwent fusion involving a mean of 11.1 levels with minimum 2-year postoperative radiographic follow-up data were included. Patients who underwent L5-S1 ALIF did not have significant improvement in global sagittal alignment parameters and demonstrated a trend toward a higher rate of nonunion and hardware failure.

CONCLUSIONS

L5-S1 ALIF did not confer significant benefit in terms of global sagittal alignment and fusion rates in patients undergoing multilevel lumbosacral fusion. Given these results and that L5-S1 ALIF is associated with increased surgical morbidity, surgeons should be judicious in including L5-S1 ALIF in large multilevel constructs.

Postoperative adverse events secondary to iatrogenic vascular injury during anterior lumbar spinal surgery

BACKGROUND

Anterior lumbar spine surgery (ALSS) requires mobilization of the great vessels, resulting in a high risk of iatrogenic vascular injury (VI). It remains unclear whether VI is associated with increased risk of postoperative complications and other related adverse outcomes.

PURPOSE

The purpose of this study was to (1) assess the incidence of postoperative complications attributable to VI during ALSS, and (2) outcomes secondary to VI such as procedural blood loss, transfusion of blood products, length of stay (LOS), and in hospital mortality.

STUDY DESIGN

Retrospective propensity-score matched, case-control study at 2 academic and 3 community medical centers, PATIENT SAMPLE: Patients 18 years of age or older, undergoing ALSS between January 1st, 2000 and July 31st, 2019 were included in this analysis.

OUTCOME MEASURES

The primary outcome was the incidence of postoperative complications attributable to VI, such as venous thromboembolism, compartment syndrome, transfusion reaction, limb ischemia, and reoperations. The secondary outcomes included estimated operative blood loss (milliliter), transfused blood products, LOS (days), and in-hospital mortality.

METHODS

In total, 1,035 patients were identified, of which 75 (7.2%) had a VI. For comparative analyses, the 75 VI patients were paired with 75 comparable non-VI patients by propensity-score matching. The adequacy of the matching was assessed by testing the standardized mean differences (SMD) between VI and non-VI group (>0.25 SMD).

RESULTS

Two patients (2.7%) had VI-related postoperative complications in the studied period, which consisted of two deep venous thromboembolisms (DVTs) occurring on day 3 and 7 postoperatively. Both DVTs were located in the distal left common iliac vein (CIV). The VI these patients suffered were to the distal inferior vena cava and the left CIV, respectively. Both patients did not develop additional complications in consequence of their DVTs, however, did require systemic anticoagulation and placement of an inferior vena cava filter. There was no statistical difference with the non-VI group where no instances (0%) of postoperative complications were reported (p=.157). No differences were found in LOS or in hospital mortality between the two groups (p=.157 and p=.999, respectively). Intraoperative blood loss and blood transfusion were both found to be higher in the VI group in comparison to the non-VI group (650 mL, interquartile range [IQR] 300-1400 vs. 150 mL, IQR 50-425, p≤.001; 0 units, IQR 0-3 vs. 0 units, IQR 0-1, p=.012, respectively).

CONCLUSION

This study found a low number of serious postoperative complications related to VI in ALSS. In addition, these complications were not significantly different between the VI and matched non-VI ALSS cohort. Although not significant, the found DVT incidence of 2.7% after VI in ALSS warrants vigilance and preventive measures during the postoperative course of these patients.

Management of Vascular Complications during Anterior Lumbar Spinal Surgery Using Mini-Open Retroperitoneal Approach

BACKGROUND

Anterior retroperitoneal spine exposure has become increasingly performed for the surgical treatment of various spinal disorders. Despite its advantages, the procedure is not riskless and can expose to potentially life-threatening vascular lesions. The aim of this review is to report the vascular lesions that can happen during anterior lumbar spinal surgery using mini-open retroperitoneal approach and to describe their management.

METHODS

A systematic literature search was performed according to PRISMA to identify studies published in English between January 1980 and December 2019 reporting vascular complications during anterior lumbar spinal surgery with mini-open retroperitoneal approach. Three authors independently conducted the literature search on PubMed/Medline database using a combination of the following terms: "spinal surgery", "anterior lumbar surgery (ALS)", "anterior lumbar interbody fusion (ALIF)", "lumbar total disc replacement", "artificial disc replacement", "vascular complications", "vascular injuries". Vascular complications were defined as any peri-operative or post-operative lesions related to an arterial or venous vessel. The management of the vascular injury was extracted.

RESULTS

Fifteen studies fulfilled the inclusion criteria. Venous injuries were observed in 13 studies. Lacerations and deep venous thrombosis ranged from 0.8% to 4.3% of cases. Arterial lesions were observed in 4 studies and ranged from 0.4% to 4.3% of cases. It included arterial thrombosis, lacerations or vasospasms. The estimated blood loss was reported in 10 studies and ranged from 50 mL up to 3000 mL. Vascular complications were identified as a cause of abortion of the procedure in 2 studies, representing respectively 0.3% of patients who underwent ALS and 0.5% of patients who underwent ALIF.

CONCLUSION

Imaging pre-operative planning is of utmost importance to evaluate risk factors and the presence of anatomic variations in order to prevent and limit vascular complications. Cautions should be taken during the intervention when manipulating major vessels and routine monitoring of the limb oxygen saturation should be systematically performed for an early detection of arterial thrombosis. The training of the surgeon access remains a key-point to prevent and manage vascular complications during anterior lumbar spinal surgery with mini-open retroperitoneal.

Treatment of Lumbosacral Tuberculosis with Significant Vertebral Body Loss Using Single-Stage Posterior Surgical Management with a Structural Autograft Combined with a Titanium Mesh Cage

OBJECTIVE

Treatment of lumbosacral tuberculosis is still controversial. In our study, we assessed the efficacy and feasibility of single-stage posterior debridement, interbody fusion using a structural autograft combined with a titanium mesh cage, and posterior instrumentation for the treatment of lumbosacral tuberculosis with significant vertebral body loss.

METHODS

From May 2011 to June 2018, 15 patients with lumbosacral tuberculosis with significant vertebral body loss had undergone single-stage posterior debridement, interbody fusion using a structural autograft combined with a titanium mesh cage, and posterior instrumentation. The pre- and postoperative lumbosacral angle, visual analog scale score, erythrocyte sedimentation rate, C-reactive protein, and neurological status were assessed.

RESULTS

Surgery was successful for all patients, and no patient experienced tuberculosis recurrence during an average follow-up period of 27.3 months (range, 12-60 months). After surgery, the erythrocyte sedimentation rate and C-reactive protein for all patients had returned to normal within 3 months. At the final follow-up examination, the neurological status had improved in all patients who had had neurological deficits preoperatively. The mean preoperative lumbosacral angle was 12.6° (range, 6.7°-17.9°), and had increased to 27.7° (range, 24.3°-34.6°) after surgery. The average lumbosacral angle was 26.4° (range, 22.1°-32.3°), with an average loss of 1.4° (range, 0.6°-2.3°) at the final follow-up visit.

CONCLUSIONS

The combination of single-stage posterior debridement, interbody fusion using structural autografts with a titanium mesh cage, and posterior instrumentation is an effective and safe option for the treatment of lumbosacral tuberculosis with significant vertebral body loss.

Iliocava junction to L4-L5 disc anatomical relationship in L5-S1 isthmic spondylolisthesis

BACKGROUND

Anterior lumbar interbody fusion finds a place in L5-S1 isthmic spondylolisthesis (ISPL) treatment. Extension of this arthrodesis at L4-L5 level is sometimes required. Anterior approach of the L4L5 disc is considered difficult due to the anatomical relationship between the iliocava junction (ICJ) and the spine.

HYPOTHESIS

Does the lumbosacral deformation induced by ISPL allows anterior approach of L4-L5 disc between the iliac?

STUDY DESIGN

Retrospective radiographic analysis of consecutive patients.

METHODS

This retrospective imaging study of a continuous series of 97 patients treated for an L5-S1 ISPL involved radiological parameters specific to ISPL and pelvic-sagittal balance. The distance between the ICJ and the L4 lower endplate was measured in millimeters. The factors influencing this distance were sought in order to identify a predictive model of high ICJ.

RESULTS

The ICJ took a cranial position with respect to the L4-L5 disc with an average distance of 1.8mm±16.4. This distance was statistically higher in the case of high-grade ISPL (p<0.01). The high ICJ position was correlated with a high Taillard index (r=0.39; CI_95% [0.13; 0.61]; p<.001) and a low lumbar-sacral angle (LSA) (r=-0.33; CI_95% [-0.56; -0.06]; p<0.01). Among the parameters specific to spino-pelvic statics, pelvic incidence, pelvic tilt and lumbar lordosis had similar correlations (r>0.30).

CONCLUSION

ISPL induces a geometric deformation of the lumbosacral hinge which modifies its anatomical relations with the ICJ. The anterior approach technique of L4-L5 disc in the presence of an L5-S1 ISPL is possible between the iliac veins for the large displacement and low LSA forms.

LEVEL OF EVIDENCE

IV, retrospective analysis.

Isolated unstable burst fractures of the fifth lumbar vertebra: functional and radiological outcome after posterior stabilization with reconstruction of the anterior column: About 6 cases and literature review

INTRODUCTION

L5 burst fractures represent a small percentage of all spine fractures. Treatment strategy has not yet been standardized. Anatomical features and their biomechanical characteristics create fracture patterns which differ from those at the thoracolumbar junction. The objective of this study was to evaluate L5 burst fracture surgical treatment outcomes after posterior stabilization and reconstruction of the anterior column.

PATIENTS AND METHODS

Six patients with fifth lumbar isolated unstable burst fractures were analyzed. Medical records, radiographs, and clinical scores were obtained. The results were evaluated based on restoration of vertebral body height, spinal lordosis/kyphosis, canal compromise and sagittal alignment at several phases of treatment.

RESULTS

No patient showed neurologic deterioration, regardless of treatment. The median preoperative anterior vertebral height was 41mm and postoperative was 48mm. The median preoperative kyphotic angle as measured by Cobb angle (local and regional) was 21.5 degrees and 33 degrees which improved respectively by 7.5 and 5.5 degrees following instrumentation. The median amount of backward protrusion of bony fragment into the canal was measured at 67% preoperatively and at 35% postoperatively. There were no pseudarthrosis and anterior arthrodesis solid fusion was visible in all cases. There were a sagittal alignment restoration. At one year of follow up, fusion was obtained in all the cases, all patients had minimal to moderate disability using Oswestry Disability Index. The ability to return to work revealed a good-to-excellent long-term result.

DISCUSSION

The results of treatment of 5th lumbar unstable burst fractures with posterior stabilization and reconstruction of the anterior column show benefit on durable functional outcome, spine stabilization and radiologic parameters.

LEVEL OF EVIDENCE

IV, retrospective study.

Efficacy and radiographic analysis of oblique lumbar interbody fusion in treating lumbar degenerative spondylolisthesis with sagittal imbalance

The aim of this study was to evaluate the effectiveness of OLIF (oblique lumbar interbody fusion) in the treatment of lumbar degenerative spondylolisthesis with sagittal imbalance. Fifty-nine patients were included in our analysis. Included patients were divided into 2 groups according to the surgical techniques: PLIF (posterior lumbar interbody fusion) (n = 31) and OLIF + PSF (OLIF combined with posterior spinal fixation) (n = 28). Perioperative radiographic parameters, complications, and clinical outcome from each group were assessed and compared. The operation time for both groups was 165.1 min in the OLIF group and 182.1 min in the PLIF group (P < 0.05). The intraoperative blood loss was 190.6 ml in the OLIF group and 356.3 ml in the PLIF group (P < 0.05). The number of intraoperative and postoperative complications for both groups was 7 in the OLIF group and 11 in the PLIF group. Significant clinical improvement was observed in VAS scores and ODI when comparing preoperative evaluation and final follow-up. The preoperative SVA (the distance from the posterosuperior corner of S1body to the C7 plumb line), PI (pelvic incidence), LL (lumbar lordosis), PI-LL mismatch, DH (disc height), and lumbar Cobb angles of both groups were similar. The postoperative and final follow-up SVA, LL, PI-LL mismatch, and disc height were improved in both groups, and a statistical difference was found between both groups (P < 0.05). An improvement of SVA, LL, PI-LL mismatch, and disc height at the OLIF group was better than that found at the PLIF group. An improvement in radiographic and clinical outcomes for the OLIF group was better than that seen for the PLIF group. Then, OLIF had a more curative effect in lumbar degenerative spondylolisthesis with sagittal imbalance.

Improving blood product utilization at an ambulatory surgery center: a retrospective cohort study on 50 patients with lumbar disc replacement

Background

There is minimal literature discussing anterior lumbar spine surgery in ambulatory surgery centers (ASCs). The main concern with the anterior approach to the lumbar spine is the potential for injury to great vessels. In our facility, there are two units of crossmatched blood available in addition to cell saver during the procedure. We retrospectively looked at 50 cases of lumbar total disc arthroplasty (TDA) in our ASC to determine utilization of blood products.

Methods

Medical records of 50 consecutive patients who underwent a lumbar TDA at a single ASC were reviewed. Surgeries completed at the ASC were all transferred from the post anesthesia care unit to an attached convalescence care center which allows up to 3 days of observation. Patients who had either a 1 or 2 level lumbar TDA were included in the study. Data consisting of demographics, American Society of Anesthesiologist Physical Status Classification System, length of stay, estimated blood loss, cell saver volume, transfusion, perioperative and postoperative complications were recorded. Preoperative, perioperative and postoperative medical records were reviewed.

Results

Medical records of 50 consecutive patients were reviewed. The mean age was 40.86 ± 9.45. Of these, 48 (96%) had a 1-level lumbar TDA, 1(2%) had a 2-level lumbar TDA, 1 (2%) had a lumbar TDA at L4/5 and an anterior lumbar interbody fusion at L5/S1. There were no mortalities; no patient had recorded perioperative complications. No patients received allogeneic blood transfusion, 4 (8%) were re-transfused with cell saver (2 receiving approximately 400 ml and 2 receiving approximately 200 ml of re-transfused blood). All 50 (100%) were discharged home in stable condition. We had 30-day follow-up data on 35 of 50 patients. Of the 35 patients reviewed, three (8.5%) of the patients were readmitted to the hospital. One additional patient was seen in the emergency department and discharged home after negative testing. No patient was readmitted for post-operative anemia.

Conclusion

The routine use of both cell saver and crossmatched blood in the operating suite for lumbar TDA may be an over-utilization of healthcare resources. In our review of 50 patients, we had no need for transfusion of allogeneic packed red blood cells (PRBCs) and only four of the 50 patients had enough blood output for re-transfusion from the cell saver. This opens the conversation for alternatives to crossmatched PRBCs being held in the operating room. Such alternatives may be the use of cell salvage, only type O blood in a cooler for each patient or keeping type O blood on constant hold in ASCs.

Comparison of Anterior only and Combined Anterior and Posterior Approach in Treating Lumbosacral Tuberculosis

A combined anterior and posterior (AP) surgical approach is a popular treatment modality of lumbosacral tuberculosis, but it is often traumatic and complicated. The present study aims to find whether the anterior only approach with the ARCH plate system is less invasive than the AP approach in treating lumbosacral tuberculosis. The ARCH plate system is an innovative anatomic lumbosacral anterior multi-directional locking plate system which was devised with due consideration to the anatomic features of the lumbosacral spine and irregular destruction of involved vertebral endplates. In this retrospective study, 32 patients with lumbosacral tuberculosis underwent surgeries via either the anterior only approach (ARCH group, 18 patients) using the ARCH system or the conventional combined anterior and posterior approach (AP group, 14 patients). American Spinal Injury Association (ASIA) scores, Visual Analogue Scale (VAS) scores, Oswestry Disability Index (ODI), bone union status, ESR, CRP, intervertebral foraminal height between L5 and S1, the vertical height between the anterior upper edge of L5 and S1 vertebral body, lumbosacral angle, and the physiological lordosis of between L1 and S1 from both groups were recorded and compared. All patients were followed up for at least two years. The average duration of operation, blood loss, and length of hospital admission of the ARCH group (154.6 min, 361.1 ml&18.3days) was significantly smaller and shorter(p < 0.001, p < 0.001 & p = 0.008) that those of the AP group(465.5 min, 814.3 ml & 24.6days). The ODI score(p = 0.08, 0.471, 0.06, 0.07, 0.107), the VAS score(p = 0.099, 0.249, 0.073, 0.103, 0.273), the intervertebral foraminal height between L5 and S1(p = 0.826, 0.073, 0.085), L5-S1 height(p = 0.057, 0.234, 0.094), lumbosacral angle(p = 0.052, 0.242, 0.825), and L5-S1 lordosis(p = 0.146, 0.129, 0.053) of both groups showed no significant difference in any of the time points. The anterior only approach using the ARCH system is as effective as the combined anterior and posterior approach and is less traumatic in treating lumbosacral tuberculosis.

Predictors and Outcomes of Paramedian Incisional Hernia After Anterior Spine Exposure

BACKGROUND

Anterior exposures for lumbar spine surgery are increasingly common for treating various spinal pathologies. A retroperitoneal approach via a paramedian incision has grown rapidly in popularity, but little is known about the risk of incisional hernia development with this technique. We sought to assess the incidence of paramedian incisional hernia development and identify risk factors that are associated with occurrence.

MATERIALS AND METHODS

We conducted a retrospective review of all patients who underwent anterior lumbar spine exposure by a paramedian approach between 2012 and 2017 at a single, tertiary medical center. The primary outcome was the development of postoperative paramedian incisional hernia.

RESULTS

Of the 735 patients included in the study, 445 (60.5%) were women, and the mean (standard deviation) age of all patients was 60 y (12.4). Nearly all (97.4%) paramedian approaches were performed with a vascular surgeon present. Median follow-up time was 10 mo (interquartile range 3.5-19.9). Postoperative paramedian hernia developed in 20 patients (2.7%), of which 14 underwent repair. The mean (standard deviation) size of the hernia was 13.5 cm (5.5); 9 of 14 (64%) were repaired with synthetic mesh, whereas 3 of 14 (21%) required bowel resection. On multivariate analysis, risk factors associated with hernia development were male gender (0.045), higher American Society of Anesthesiologists class (0.039), history of abdominal surgery (P = 0.013), and postoperative intensive care unit admission (P = 0.02).

CONCLUSIONS

A paramedian approach for anterior lumbar spine exposure resulted in a low rate of incisional hernia with minimal morbidity. Surgeons involved in these collaborative procedures should consider the risk factors that predispose patients to develop these hernias.

Complications Associated With Minimally Invasive Anterior to the Psoas (ATP) Fusion of the Lumbosacral Spine

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

To analyze complications associated with minimally invasive anterolateral retroperitoneal antepsoas lumbosacral fusion (MIS-ATP).

SUMMARY OF BACKGROUND DATA

MIS-ATP provides anterolateral access to the lumbar spine allowing for safe anterior lumbar interbody fusions between T12-S1. Anecdotally, many surgeons believe that ATP approach is not feasible at L5-S1 level, predisposing to catastrophic vascular injuries. This approach may help overcome limitations associated with conventional straight anterior lumbar interbody fusions, MIS lateral lumbar interbody fusion, and oblique lateral interbody fusion.

METHODS

A detailed retrospective chart review of patients who had underwent MIS-ATP approach for lumbar fusion between T12-S1 was performed. Available electronic data from surgeries performed between January 2008 and March 2017 was carefully screened for surgical patients treated for spondylolisthesis, spondylosis, stenosis, sagittal, and/or coronal deformity. Detailed review of electronic medical records including operative notes, progress notes, discharge summaries, laboratory results, imaging reports, and clinic visit notes performed by a single independent reviewer not involved in patient care for documented complications. A complication is defined as any adverse event related to the index spine procedure for which patient required specific intervention or treatment.

RESULTS

Nine hundred forty patients with a total of 2429 interbody fusion levels performed via MIS-ATP were identified during the study period. Sixty-seven patients (7.2%) sustained one or more complications during the perioperative period, of which 25.5% were surgical and 74.5% were medical. Overall, 78 (8.2%) surgical complications pertaining to the index procedure were noted during a postoperative period of 1 year from the date of surgery. No major vascular or direct visceral injuries were encountered.

CONCLUSIONS

MIS-ATP approach provides a safe access to anterolateral interbody fusions between T12-S1. The ATP approach is performed by the spine surgeon, does not require neuromonitoring, and warrants minimal to no psoas muscle retraction resulting in significantly reduced postoperative thigh pain and rare neurologic injuries. Additionally, the direct and clear visualization of the retroperitoneal vasculature provided by the ATP approach minimizes the risk of inadvertent vascular injury.

LEVEL OF EVIDENCE

4.

Multilevel Anterior Lumbar Interbody Fusion Combined with Posterior Stabilization in Lumbar Disc Disease-Prospective Analysis of Clinical and Functional Outcomes

Objective  This was a prospective controlled study with lumbar degenerative disc disease patients submitted to instrumented anterior lumbar interbody fusion (ALIF) combined with posterior stabilization.

Methods  A sample with 64 consecutive patients was operated by the same surgeons over 4 years. Half of the ALIFs occurred at 2 levels, 43.8% at 3 levels, and 6.25% at 1 level. Interbody cages with integrated screws, filled with bone matrix and bone morphogenetic protein 2, were used.

Results  Half of the patients had undergone previous lumbar spine surgeries, 75% presented with associated degenerative listhesis, and 62.5% had posterior lumbar compression disease. Approximately 56% of the sample had at least 1 risk factor for nonunion. The Oswestry index changed from 71.81 ± 7.22 at the preoperative assessment to 24.75 ± 7.82 at the final follow-up evaluation, while the visual analogue pain scale changed from 7.88 ± 0.70 to 2.44 ± 0.87 ( p  < 0.001). Clinical and functional improvements increased with the number of operated levels, proving the efficacy of multilevel ALIF, performed in 93.75% of the sample. The global complication rate was of 7.82%, with no major complications. No cases of nonunion were observed.

Conclusion  Instrumented ALIF combined with posterior stabilization is a successful option for uni- and multilevel degenerative disc disease of the L3 to S1 segments, even in the significant presence of risk factors for nonunion and of previous lumbar surgeries, assuring very satisfactory clinical-functional and radiographic outcomes with a low medium-term complication rate.

Iatrogenic Bowel Injury Following Minimally Invasive Lateral Approach to the Lumbar Spine: A Retrospective Analysis of 3 Cases

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

Anterior approaches are often used during lumbar interbody fusion procedures. Visceral injuries (bowel injuries) are rare but represent a primary risk during anterior approaches to the lumbar spine. Left untreated, these injuries can result in significant complications. The aim of this study was to investigate the presentation and management of bowel injury cases following anterior approaches to the lumbar spine to raise the surgeon's awareness of this rare complication.

METHODS

All direct anterior, oblique anterior, and transpsoas lumbar interbody fusion surgeries performed at our institution between 2012 and 2016 were analyzed retrospectively. Charts were screened for cases requiring return to the operating room owing to a suspected bowel injury and details of the case were extracted for illustrative purposes.

RESULTS

A total of 775 anterior lumbar surgeries were conducted at a single tertiary care institution between July 2012 and June 2017. A total of 590 transpsoas lumbar interbody fusion (TPIF) surgeries were performed. Four patients, each having undergone TPIF, were suspected of bowel injury and underwent an exploratory laparotomy. At surgery, 3 patients were confirmed to have a bowel injury, giving a procedure-specific incidence of 0.51% and overall incidence of 0.39%. Among the 3 confirmed bowel injury cases, average delay between surgery and visceral injury diagnosis was 4.7 days (range 3-7 days).

CONCLUSIONS

We noted abdominal pain, distention, and fever as the most common findings in the setting of a visceral injury. A high index of suspicion and computed tomography imaging remain critical for identifying postoperative bowel injuries.

Outcomes of direct lateral interbody fusion (DLIF) in an Australian cohort

Background

Direct lateral interbody fusion (DLIF) mitigates many of the vascular complications and bony resections associated with other interbody fusion techniques. However, there are concerns regarding postoperative neural complications and that indirect decompression of the foramen has not been consistently demonstrated. This study prospectively assessed the clinical and radiological outcomes and the complication rates of the DLIF approach.

Methods

A prospective review was conducted of the first 50 consecutive DLIF cases of a single neurosurgeon between 2010 and 2014. Clinical outcomes were assessed using Visual Analogue Scale (VAS), Oswestry Disability Index (ODI) and Roland Morris Disability Questionnaire (RMDQ) surveys. Radiological outcomes, including spondylolisthesis, disc height, local disc angle, lumbar lordosis and foraminal height and width, were measured using Surgimap Spine software at the preoperative, 6 weeks, 6 months, and 12 months postoperative follow-up. Complication rates were also reported.

Results

A total of 50 patients (84 levels) were treated with DLIF. The mean patient age was 68.2±9.8 years and 62.0% were female. At latest follow-up, mean VAS pain score improved from 7.7±1.5 to 1.9±0.9 (P<0.0001), mean ODI improved from 42.1±14.5 to 16.9±6.7 (P<0.0001) and mean RMDQ score improved from 12.1±5.2 to 6.2±4.7 (P<0.0001). Mean spondylolisthesis reduced from 7.5%±6.5% to 1.3%±1.1% at 6 weeks (P<0.0001), 0.95%±0.74% at 6 months (P<0.0001) and recurred to 1.9%±1.7% at 12 months postoperatively (P=0.0006). Mean anterior disc height improved from 7.3±3.2 to 11.6±2.5 mm at 6 weeks (P<0.0001), 12.2±3.3 mm at 6 months (P<0.0001) and 9.8±2.1 mm at 12 months (P=0.0032) postoperatively. Mean posterior disc height improved from 4.4±2.0 to 6.8±2.1 mm at 6 weeks (P<0.0001), 6.6±2.5 mm at 6 months (P=0.0003), and 5.9±1.4 mm at 12 months (P=0.0039) postoperatively. Mean local disc angle improved from 7.0°±3.7° to 9.2°±3.3° at 6 weeks (P=0.0072), 10.4°±3.9° at 6 months (P=0.0013) and 8.2°±2.9° at 12 months (P=0.2487) postoperatively. No significant postoperative changes in lumbar lordosis were observed. Mean foraminal height improved from 18.3±3.5 to 21.5±3.9 mm at 6 weeks (P=0.0004), 20.6±3.4 mm at 6 months (P=0.0266), and 18.7±1.9 mm at 12 months (P=0.8021) postoperatively. Mean foraminal width improved from 7.9±2.0 to 10.2±2.8 mm at 6 weeks (P=0.0001), 9.4±2.6 mm at 6 months (P=0.0219) and 8.3±1.6 mm at 12 months (P=0.5734) postoperatively. Fusion rate at 6 and 12 months was 62.2% and 89.2%, respectively. A total of 6 patients (12%) had postoperative complications. Three patients (6%) had pain-related psoas muscle weakness and 3 patients (6%) had sensory neural complications that had resolved entirely by 8 and 16 weeks postoperatively, respectively.

Conclusions

The study provides encouraging short and medium-term clinical and radiological results for DLIF. In this patient series, there was a low complication rate with no permanent neural injury reported.

Surgical approach and management outcomes for junction tuberculous spondylitis: a retrospective study of 77 patients

Background

Junction tuberculous spondylitis involves the stress transition zone of the spine and has a high risk of progression to kyphosis or paraplegia. Problems still exist with treatment for spinal junction tuberculosis. This study investigated the surgical approach and clinical outcomes of junction spinal tuberculosis.

Methods

From June 1998 to July 2014, 77 patients with tuberculous spondylitis were enrolled. All patients received 2–3 weeks of anti-tuberculous treatment preoperatively; treatment was prolonged for 2–3 months when active pulmonary tuberculosis was present. The patients underwent anterior debridement and were followed up for an average of 29.4 months clinically and radiologically.

Results

The cervicothoracic junction spine (C7-T3) was involved in 15 patients. The thoracolumbar junction spine (T11-L2) was involved in 39 patients. The lumbosacral junction spine (L4-S1) was involved in 23 patients. Two patients with recurrence underwent reoperation; the drugs were adjusted, and all patients achieved bone fusion. The preoperative cervicothoracic and thoracolumbar kyphosis angle and lumbosacral angle were 31.4 ± 10.9°, 32.9 ± 9.2°, and 19.3 ± 3.7°, respectively, and the corresponding postoperative angles were ameliorated significantly to 9.1 ± 3.2°, 8.5 ± 2.9°, and 30.3 ± 2.8°. The preoperative ESR and C-reactive protein level of all patients were 48.1 ± 11.3 mm/h and 65.5 ± 16.2 mg/L which decreased to 12.3 ± 4.3 mm/h and 8.6 ± 3.7 mg/L at the final follow-up, respectively. All patients that had neurological symptoms achieved function status improvement at different degrees.

Conclusion

For spinal tuberculosis of spinal junctions, anterior debridement, internal fixation, and fusion can be preferred and achieved. If multiple segment lesions are too long or difficult for operation of anterior internal fixation, combining posterior pedicle screw fixation is appropriate.

Thromboembolic risk after lumbar spine surgery: a cohort study on 325 000 French patients

Essentials The risk of venous thromboembolism (VTE) after lumbar spine surgery (LBS) is not precisely known. More than 320 000 patients who underwent LBS in France between 2009 and 2014 were followed-up. The overall risk of VTE after LBS is less than 1% but modulated by patient and procedural factors. Surgical device implantation, anterior approach and complex surgery increase the risk of VTE. SUMMARY: Background Postoperative venous thromboembolism (VTE) is a severe complication, the risk of which after lumbar spine surgery (LBS) is not precisely known. Objective To estimate the incidence of VTE after LBS, and to identify individual and surgical risk factors. Methods All patients aged >18 years who underwent LBS in France between 2009 and 2014 were identified. Among 477 024 patients screened, exclusions concerned recent VTE or surgery, and multiple surgeries during the same hospital stay. Results In 323 737 patients (mean age 52.9 years, 51.4% male), we observed 2911 events (0.91%) after a median time of 12 days (Q1-Q3: 5-72 days). The multivariate adjusted Cox model showed increased risks associated with age (4% per year of age; 95% confidence interval [CI] 3.8-4.3), obesity (hazard ratio [HR] 1.32, 95% CI 1.18-1.46), active cancer (HR 1.65, 95% CI 1.5-1.82), previous thromboembolism (HR 5.41, 95% CI 4.74-6.17), severe paralysis (HR 1.47, 95% CI 1.17-1.84), renal disease (HR 1.28, 95% CI 1.04-1.6), psychiatric disease (HR 1.21, 95% CI 1.1-1.32), use of antidepressants (HR 1.13, 95% CI 1.03-1.24), use of contraceptives (HR 1.56, 95% CI 1.19-2.03), extended surgery for scoliosis (HR 3.61, 95% CI 2.96-4.4), implantation of pedicular screws with a 'dose-effect' association, and an anterior approach (HR 1.97, 95% CI 1.6-2.43) or a combined approach (HR 2.03, 95% CI 1.44-2.84). Conclusions The overall VTE risk after LBS is moderate (< 1%) but is widely modulated by several easily identifiable risk factors. The surgical community should be aware of this heterogeneity, adapt prevention according to patients and to the procedure, and use drug prophylaxis in the event of a high risk being present.

Integrated anatomy of the neuromuscular, visceral, vascular, and urinary tissues determined by MRI for a surgical approach to lateral lumbar interbody fusion in the presence or absence of spinal deformity

Introduction

To comprehensively investigate the anatomy of the neuromuscular, visceral, vascular, and urinary tissues and their general influence on lateral lumbar interbody fusion (LLIF) surgery in the presence or absence of spinal deformity.

Methods

We retrospectively reviewed 100 consecutive surgery cases for lumbar degenerative disease of patients aged on average 70.5 years and of which 67 were women. A sagittal vertical axis deviation of more than 50 mm was defined as adult spinal deformity (ASD: 50 patients). The degenerative disease of the other patients was defined as lumbar spinal stenosis (LSS: 50 patients). We analyzed the relative anatomical position of the psoas major muscle, lumbar plexus, femoral nerves, inferior vena cava, abdominal aorta and its bifurcation, ureter, testicular or ovarian artery, kidney and transverse abdominal muscle in patients with ASD or with LSS, using preoperative magnetic resonance imaging (MRI).

Results

For patients with ASD, the L4-5 intervertebral disk was closer to the lumbar nerve plexus than it was in those with LSS (p < 0.0001), and a rising psoas sign at the L4-5 disk was significantly more frequent in patients with ASD than in those with LSS (p < 0.05). The aortic bifurcation frequently appeared at the level of L4-5 in patients with either degenerative disease, so the common iliac artery may pass near the disk. The inferior vena cava passed closer to the center of the L4-5 disk in patients with ASD than it did in those with LSS (p < 0.05). The transverse abdominal muscle at L2-3, L3-4, and L4-5 was closer to and less than 3 mm from the kidneys in many more patients with ASD than was the case for patients with LSS (p = 0.3, p < 0.05, p = 0.29, respectively).

Conclusions

We recommend careful preoperative MRI to determine the location of organs to help to avoid intraoperative complications during LLIF surgery, especially for patients with ASD.

Total Disc Arthroplasty Versus Anterior Interbody Fusion in the Lumbar Spine Have Relatively a Few Differences in Readmission and Short-term Adverse Events

STUDY DESIGN

Retrospective matched cohort study of prospectively collected data.

OBJECTIVE

To compare rates of adverse events and readmission between lumbar total disc arthroplasty (TDA) and anterior lumbar interbody fusion (ALIF) using the American College of Surgeons National Surgical Quality Improvement Program database.

SUMMARY OF BACKGROUND DATA

TDA and ALIF may be considered for similar degenerative indications. However, there have been a few large-cohort comparison studies of short-term clinical outcomes for these procedures.

METHODS

The 2011-2015 NSQIP databases were retrospectively queried to identify patients who underwent elective stand-alone ALIF and TDA. After propensity matching, the association of procedure type with adverse events and readmission was determined using McNemar's test. Operative time and postoperative length of stay (LOS) were compared using multivariate linear regression. Risk factors for adverse events were determined using multivariate Poisson regression.

RESULTS

In total, 1801 ALIF and 255 TDA patients were identified. After matching with propensity scores, there were no significant differences in the rates of any adverse event, serious adverse events, individual adverse events, or readmission other than blood transfusion, which occurred more frequently in the ALIF cohort (3.92% vs. 0.39%, P = 0.007). Operative time was not significantly different between the two cohorts, but postoperative LOS was significantly longer for ALIF cases (+0.28 days, P < 0.001). When evaluating 10 preoperative variables as potential risk factors for adverse events and readmission after TDA and ALIF, the majority of results were similar.

CONCLUSION

The only identified differences in perioperative outcomes between TDA and ALIF were a 3.53% higher incidence of blood transfusion and 0.28-day longer LOS for the ALIF group. These results suggest overall similar short-term general-health outcomes between the two groups, and that the choice between the two procedures, for the appropriately selected patient, should be based on longer-term functional outcomes.

LEVEL OF EVIDENCE

3.

Effects of release and decompression techniques on nerve roots through percutaneous transforaminal endoscopic discectomy on patients with central lumbar disc herniation

The clinical effects and safety of release and decompression techniques on nerve roots through percutaneous transforaminal endoscopic discectomy (PTED) while treating patients with central lumbar disc herniation (CLDH) were explored. Patient cases of lumbar and leg pain treated in Bethune International Peace Hospital from July 2013 to October 2015 were collected retrospectively. The patients in these cases received imaging examinations such as computed tomography and magnetic resonance imaging. Among these cases, 37 CLDH patients with no other complications were selected for this study. A total of 22 males and 15 females aged 28–54 years, with an average age of 36.8±1.5 years, were the subjects of the study. Their disease course was from 1 month to 3 years, with a median course time of 1.5 years. Visual analogue scale (VAS), Japanese Orthopaedic Association (JOA) scoring and the MacNab method were used to evaluate treatment effects. After permission from patients or their family members, release and decompression techniques of nerve roots were performed through PTED. All patients had successful surgery. Their average surgery time was 41.3 (25.5–57.1) min. A physician followed-up each patient from 0 to 18 months after surgery, with the average follow-up period of 12.1 months. VAS scoring of lower limbs was 7.95±0.82 before surgery and 2.28±0.35, 3 months after surgery. VAS scoring of lower limbs was 2.06±0.58, 1 year after surgery and 2.12±0.23 at the last follow-up appointment. JOA scoring was 12.6±0.72 before surgery and 20.4±1.08, 3 months after surgery. JOA scoring was 21.1±0.82 1 year after surgery and 21.2±0.36 at the last follow-up. Differences are of statistical significance (P<0.05). There were no complications for any of the cases. One patient did not improve after surgery, so a laminectomy and bone grafting internal fixation were performed. Two patients relapsed after surgery and received laminectomy and bone grafting internal fixation. The total percentage of excellent and good rates was 83.5%. In conclusion, release and decompression techniques on nerve roots using PTED while treating CLDH resulted in a safe, effective and less traumatic outcome with fewer complications and quicker pain relief than alternative treatments. Due to the results of this study, the use of these techniques in treating CLDH should be more widely considered.

[Imaging and biomechanics researches of reconstructing lumbosacral stability after L 5 vertebrectomy via anterolateral approach]

Objective

To investigate the feasibility of anterolateral approach for L 5 vertebral resection, bone grafting, and screw rod fixation by imaging and biomechanics researches.

Methods

Twenty formalized adult cadavers (12 males and 8 females) were randomly divided into 2 groups; L 5 vertebral resection, bone graft, and screw rod fixation was performed on 10 specimens by using anterolateral approach (experimental group), and on the other 10 specimens by combined anterior and posterior approach. CT scanning and three-dimensional reconstruction were performed in the experimental group; preoperative maximal safe entry angle and depth of screws and intraoperative actual entry angle and depth of screws were measured; the sacral screw position was observed after operation. The biomechanical test was done in 2 groups.

Results

Twenty specimens smoothly underwent L 5 excision and reconstruction. CT scan showed that there was no significant difference in maximal safe entry angle and depth of screws between males and females in experimental group before operation ( P>0.05); the maximal safe entry angle and depth were 51.93° and 47.88 mm for anterior screw, and were 37.04° and 46.28 mm for posterior screw. After operation, depth of the sacral anterior and posterior screws were appropriate, which did not pierce into the spinal canal. The biomechanical test results indicated that the flexion, extension, and lateral flexion displacements, and vertical compression stiffness showed no significant difference between 2 groups ( P>0.05).

Conclusion

For L 5 lesions not invading posterior column, to use L 5 vertebral resection, bone graft, and screw rod fixation by anterolateral approach is a safe and feasible method to reconstruct lumbosacral stability, with the advantages of no changing posture, less operation time and incision, and prevention of bone graft shift, but effectiveness need further be identified.

Surgical techniques for lumbo-sacral fusion

Lumbo-sacral (L5-S1) fusion is a widely performed procedure that has become the reference standard treatment for refractory low back pain. L5-S1 is a complex transition zone between the mobile lordotic distal lumbar spine and the fixed sacral region. The goal is to immobilise the lumbo-sacral junction in order to relieve pain originating from this site. Apart from achieving inter-vertebral fusion, the main challenge lies in the preoperative determination of the fixed L5-S1 position that will be optimal for the patient. Many lumbo-sacral fusion techniques are available. Stabilisation can be achieved using various methods. An anterior, posterior, or combined approach may be used. Recently developed minimally invasive techniques are gaining in popularity based on their good clinical outcomes and high fusion rates. The objective of this conference is to resolve the main issues faced by spinal surgeons in their everyday practice.

Evolution of Design of Interbody Cages for Anterior Lumbar Interbody Fusion

Anterior lumbar interbody fusion (ALIF) is one of the surgical procedures for the relief of chronic back pain, radiculopathy and neurogenic claudication in patients with degenerative lumbar spine disease that is refractory to conservative therapy, low-grade spondylolisthesis and pseudo arthrosis. Over the past half century, both the surgical techniques and instrumentation required for ALIF have changed significantly. In particular, the designs of ALIF cage and the materials used have evolved dramatically, the common goal being to improve fusion rates and optimize clinical outcomes. The increasing popularity of ALIF is reflected by the increasing abundance of published studies reporting clinical outcomes, surgical techniques and grafting options for ALIF. Developments in cage designs include cylindrical Bagby and Kuslich, cylindrical ray, cylindrical mesh, lumbar-tapered, polyethyl-etherketone cage and integral fixation cages. Biologic implants include bone dowels and femoral ring allografts. Methods for optimization of cage design have included cage dimensions, use of novel composite cage materials and integral fixation technologies. However, the historical development and evolution of cages used for ALIF has not been extensively documented. This article therefore aims to provide an overview of the historical basis for the anterior approach, evolution in design of ALIF cage implants and potential future research directions.

Lateral interbody fusion combined with open posterior surgery for adult spinal deformity

OBJECTIVE Lateral interbody fusion (LIF) with percutaneous screw fixation can treat adult spinal deformity (ASD) in the coronal plane, but sagittal correction is limited. The authors combined LIF with open posterior (OP) surgery using facet osteotomies and a rod-cantilever technique to enhance lumbar lordosis (LL). It is unclear how this hybrid strategy compares to OP surgery alone. The goal of this study was to evaluate the combination of LIF and OP surgery (LIF+OP) for ASD. METHODS All thoracolumbar ASD cases from 2009 to 2014 were reviewed. Patients with < 6 months follow-up, prior fusion, severe sagittal imbalance (sagittal vertical axis > 200 mm or pelvic incidence-LL > 40°), and those undergoing anterior lumbar interbody fusion were excluded. Deformity correction, complications, and outcomes were compared between LIF+OP and OP-only surgery patients. RESULTS LIF+OP (n = 32) and OP-only patients (n = 60) had similar baseline features and posterior fusion levels. On average, 3.8 LIFs were performed. Patients who underwent LIF+OP had less blood loss (1129 vs 1833 ml, p = 0.016) and lower durotomy rates (0% vs 23%, p = 0.002). Patients in the LIF+OP group required less ICU care (0.7 vs 2.8 days, p < 0.001) and inpatient rehabilitation (63% vs 87%, p = 0.015). The incidence of new leg pain, numbness, or weakness was similar between groups (28% vs 22%, p = 0.609). All leg symptoms resolved within 6 months, except in 1 OP-only patient. Follow-up duration was similar (28 vs 25 months, p = 0.462). LIF+OP patients had significantly less pseudarthrosis (6% vs 27%, p = 0.026) and greater improvement in visual analog scale back pain (mean decrease 4.0 vs 1.9, p = 0.046) and Oswestry Disability Index (mean decrease 21 vs 12, p = 0.035) scores. Lumbar coronal correction was greater with LIF+OP surgery (mean [± SD] 22° ± 13° vs 14° ± 13°, p = 0.010). LL restoration was 22° ± 13°, intermediately between OP-only with facet osteotomies (11° ± 7°, p < 0.001) and pedicle subtraction osteotomy (29° ± 10°, p = 0.045). CONCLUSIONS LIF+OP is an effective strategy for ASD of moderate severity. Compared with the authors' OP-only operations, LIF+OP was associated with faster recovery, fewer complications, and greater relief of pain and disability.

L5/S1 Fusion Rates in Degenerative Spine Surgery: A Systematic Review Comparing ALIF, TLIF, and Axial Interbody Arthrodesis

STUDY DESIGN

Systematic review.

OBJECTIVE

To determine the fusion rate of an anterior lumbar interbody fusion (ALIF), transforaminal lumbar interbody fusion (TLIF), and axial arthrodesis at the lumbosacral junction in adult patients undergoing surgery for 1- and 2-level degenerative spine conditions.

SUMMARY OF BACKGROUND DATA

An L5/S1 interbody fusion is a commonly performed procedure for pathology such as spondylolisthesis with stenosis; however, it is unclear if 1 technique leads to superior fusion rates.

MATERIALS AND METHODS

A systematic search of MEDLINE was conducted for literature published between January 1, 1992 and August 17, 2014. All peer-reviewed articles related to the fusion rate of L5/S1 for an ALIF, TLIF, or axial interbody fusion were included.

RESULTS

In total, 42 articles and 1507 patients were included in this systematic review. A difference in overall fusion rates was identified, with a rate of 99.2% (range, 96.4%-99.8%) for a TLIF, 97.2% (range, 91.0%-99.2%) for an ALIF, and 90.5% (range, 79.0%-97.0%) for an axial interbody fusion (P=0.005). In a paired analysis directly comparing fusion techniques, only the difference between a TLIF and an axial interbody fusion was significant. However, when only cases in which bilateral pedicle screws supported the interbody fusion, no statistical difference (P>0.05) between the 3 techniques was identified.

CONCLUSIONS

The current literature available to guide the treatment of L5/S1 pathology is poor, but the available data suggest that a high fusion rate can be expected with the use of an ALIF, TLIF, or axial interbody fusion. Any technique-dependent benefit in fusion rate can be eliminated with common surgical modifications such as the use of bilateral pedicle screws.

Biomechanical evaluation of CIBOR spine interbody fusion device

BACKGROUND

The CIBOR PEEK spinal interbody fusion device is an anterior lumbar interbody fusion construct with a hollow center designed to accommodate an osteoinductive carbon foam insert to promote bony ingrowth to induce fusion where rigid stabilization is needed.

METHODS

Three different sizes of the device were investigated. Part-I: implants were tested under axial compression and rotation using polyurethane foam blocks. Part-II: simulated 2-legged stance using cadaveric specimen using the L5-S1 lumbar spine segment. Part-III: a survey feedback form was used to investigate two orthopedic surgeons concern regarding the implant.

RESULTS

In Part-I, the subsidence hysteresis under axial compression loading was found to be statistical significant difference between these three implant sizes. It was noted that the implants had migration as rotation applied, and the amount of subsidence was a factor of the axial compression loads applied. In Part-II, a minor subsidence and carbon foam debris were observed when compared to each implant size. Poor contact surface of the implant with the end plates of the L5 or S1 vertebrae from the anterior view under maximum loads was observed; however, the implant seemed to be stable. Each surgeon has their own subjective opinion about the CIBOR implant.

DISCUSSION

Two out of the three different sizes of the device (medium and large sizes) provided appropriate rigid stabilization at the physiological loads. Neither orthopedic surgeon was 100% satisfied with overall performance of the implant, but felt potential improvement could be made.

CLINICAL RELEVANCE

This study indicates an option for operative treatment of spine interbody fusion, as the CIBOR spine interbody fusion device has a hollow center. This hollow center is designed to accommodate a carbon foam insert to promote bony ingrowth. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1157-1168, 2017.

One-Stage Anterior Approach with Arch Plate to Treat Lumbosacral Tuberculosis

This article describes the arch plate technique for treating lumbosacral tuberculosis. Lumbosacral tuberculosis often leads to the destruction of anterior vertebral columns and presacral or iliopsoas abscess, which requires an anterior approach to achieve thorough debridement. Due to the complexity of the anatomical structure of lumbosacral spine and the high requirement of fixation stability, a combined posterior approach to perform internal fixation is necessary, which is rather traumatic. On the other hand, most of the current anterior lumbosacral internal fixation systems cannot be applied to spinal tuberculosis patients who have irregular bony endplate destruction. The arch plate was designed as a cephalic narrow and caudal wide trapezoid or triangle outline according to the preliminary anatomic research. In terms of the endplate bony destruction, a multidirectional technique was introduced in the arch screws, which enables surgeons to arbitrarily change the direction of the screw in the range of 5°-20°, which increases the length and the inclination angles in the sagittal plane of the implant screw and makes sure that the autologous iliac bone graft fits the irregular bone destruction for maximum stability. This study demonstrated the effectiveness of one-stage anterior debridement, bone grafting, and arch plate fixation to treat lumbosacral tuberculosis. The risk of intraoperative and postoperative complications, such as injury to major vessels, could be minimized. This surgical procedure had many advantages, including a shorter operation time, less blood loss, and better functional recovery over the conventional combined anterior and posterior approach.

Imaging of lumbar spinal surgery complications

Abstract

Lumbar spine surgery for spinal stenosis is a frequently performed procedure and was the fastest growing type of surgery in the US from 1980 to 2000. With increasing surgical invasiveness, postoperative complications also tend to be higher. Cross-sectional imaging techniques (CT and MRI) are more sensitive than radiographs and play an increasingly important role in evaluation of patients with lumbar spine surgery. Their use in patients with metallic implants is somewhat limited by artefacts, which can obscure pathology and decrease accuracy and reader confidence. Metal artefact reduction techniques have been developed, which can significantly improve image quality and enable early detection of postoperative complications. Complications can occur throughout postoperative course. Early complications include hardware displacement, incidental durotomy, postoperative collections—most commonly seroma, and less likely haematoma and/or infection. Incidental durotomy with CSF leak causing intracranial hypotension has characteristic MR brain findings and diagnosis of occult leak sites have been improved with use of dynamic CT myelography. Haematomas, even when compressing the thecal sac, are usually asymptomatic. Early infection, with nonspecific MR findings, can be diagnosed accurately using dual radiotracer studies. Delayed complications include loosening, hardware failure, symptomatic new or recurrent disc herniation, peri-/epidural fibrosis, arachnoiditis, and radiculitis.

Teaching Points

• CT and MRI play an increasingly important role in evaluation of patients with lumbar spine surgery

• Complications can occur throughout the postoperative course and early detection is critical

• Artefact reduction techniques can improve image quality for early and improved detection of complications