Evolution of the Anterior Approach in Lumbar Spine Fusion

An Update in Complication Rates Associated With Anterior Lumbar Surgery: A Systematic Review and Meta-Analysis

STUDY DESIGN

Systematic Review and meta-analysis.

OBJECTIVE

To conduct an updated systematic review and meta-analysis of complications associated with different anterior fusion techniques/approaches and adjuvant resources (i.e., computed tomography angiography (CTA), rhBMP-2, and access surgeons).

METHODS

A systematic review was conducted from 1/1/2014-4/1/2024 for studies evaluating the incidence of complications associated with anterior lumbar procedures. Comparisons of complications were made between surgical approach, use of CTA, rhBMP-2, and access surgeons. Meta-analyses were conducted using a generalized linear mixed model.

RESULTS

54 studies were included in the final analysis with 8066 patients and an average follow-up of 31.2 months. The overall complication rate associated with anterior lumbar surgery was 13.1%, including an intraoperative complication rate of 3.8%, postoperative complication rate of 7.4%, infection rate of 1.5%, and reoperation rate of 1.7%. Forest plot analysis showed no significant difference in overall complication rates between open and mini-open techniques, although mini-open techniques were associated with lower overall reoperation rates. The use of CTA was associated with an increase in intraoperative and overall complications, and the use of an access surgeon was associated with a decreased risk of reoperation. The use of rhBMP-2 was not associated with overall complication risk.

CONCLUSIONS

While anterior lumbar surgery provides numerous benefits, surgeons and patients alike should be aware of the complication and safety profile prior to surgery. High quality studies are warranted to help elucidate the true benefit of certain techniques and adjuvant resources in reducing complications.

Prospective Analysis of Incisional Morbidity Associated With Anterior Surgical Approaches to the Lumbar Spine

OBJECTIVE

Anterior approaches to the lumbar spine have been used extensively for various indications but they are also associated with unique complications and have been linked with higher incisional morbidity.This study aimsto evaluate incisional morbidity related to anterior lumbar surgeries and to assess how incisional outcomes correlate with patient and surgery-related factors.

METHODS

Patients ≥18 years old and with planned anterior lumbar fusions from L1 to S1 were prospectively enrolled. Follow-up ended at two years, and patients who did not complete the follow-up were excluded. Incision was assessed for general appearance, width, color, cross-hatching, hypertrophy, and pain by using a validated scoring system and a visual analog scale (VAS). Patient and surgery-related factors were analyzed for possible correlations with complications or wound-related parameters.

RESULTS

A total of 205 patients with a mean age of 54.4 ± 11.5 were included. Significant improvements were seen in color, hypertrophy, pain, and appearance of the incision. At two years, the mean patient-based VAS for appearance was 8.6 while surgeon-based VAS was 8.8. The total rate of complications was 9%, with no incisional hernia or bulging. No significant relation was found between incision-related parameters and the demographic and surgical variables.

CONCLUSION

This study reports acceptable cosmetic results and no chronic pain after anterior lumbar surgery, which is contrary to previous reports. Together with a low total rate of complications, anterior approaches are safe when carefully executed, and have low morbidity.

Retrospective analysis of medium-term outcomes following anterior lumbar interbody fusion surgery performed in a tertiary spinal surgical centre

INTRODUCTION

Anterior lumbar interbody fusion (ALIF) can treat spondylolisthesis, degenerative disc disease and pseudoarthrosis. This approach facilitates complete discectomy, disc space distraction, indirect decompression of neural foramina and placement of large interbody devices. Several intra- and postoperative complications can be attributed to the anterior approach: vascular/visceral injury, hypogastric plexus injury and urogenital consequences. Spine-specific complications include implant migration, graft failure, pseudoarthrosis and persistent symptomology.

METHODS

This retrospective study reviewed patient demographics, medium-term outcomes and complication rates following ALIF surgery performed over a 5-year period. A total of 110 consecutive patients had undergone ALIF surgery at a single tertiary spinal centre. The database was reviewed with a primary outcome of identifying postoperative 90-day complications and whether a revision anterior operation was required after primary ALIF.

RESULTS

No patients required revision anterior operation after their primary ALIF surgery by final follow-up. Out of 110 patients, 11 (10%) recorded a complication attributed to the anterior stage of their operation within 90 days.

CONCLUSIONS

Our 90-day complication rate of 10% lies within the 2.6% acute complication and 40% overall complications rates described in previous literature. The risk of vascular/visceral injury is significant (3%) and we recommend that ALIF be performed as a dual surgeon procedure with a vascular-trained access surgeon accompanying the spinal surgeon. ALIF is a valid revision surgical option for failed posterior approaches leading to complications such as pseudoarthrosis. In our sample, 89% of patients were managed with posterior fixation to augment the anterior fusion as, biomechanically, this is a proven construct.

Pedicle Subtraction Osteotomy Versus Multilevel Anterior Lumbar Interbody Fusion and Lateral Lumbar Interbody Fusion in the Treatment of Adult Spinal Deformity: Trends, Outcomes, and Cost

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The aim of this study was to compare the outcomes of pedicle subtraction osteotomy (PSO) with multilevel anterior lumbar interbody fusion (ALIF) and lateral lumbar interbody fusion (LLIF) in posterior long-segment fusion.

BACKGROUND

PSO and ALIF/LLIF are 2 techniques used to restore lumbar lordosis and correct sagittal alignment, with each holding its unique advantages and disadvantages. As there are situations where both techniques can be employed, it is important to compare the risks and benefits of both.

PATIENTS AND METHODS

Patients aged 18 years or older who underwent PSO or multilevel ALIF/LLIF with posterior fusion of 7-12 levels and pelvic fixation were identified. 1:1 propensity score was used to match PSO and ALIF/LLIF cohorts for age, sex, and relevant comorbidities, including smoking status. Logistic regression was used to compare medical and surgical outcomes. Trends and costs were generated for both groups as well.

RESULTS

ALIF/LLIF utilization in posterior long fusion has been steadily increasing since 2010, whereas PSO utilization has significantly dropped since 2017. PSO was associated with an increased risk of durotomy ( P < 0.001) and neurological injury ( P = 0.018). ALIF/LLIF was associated with increased rates of postoperative radiculopathy ( P = 0.005). Patients who underwent PSO had higher rates of pseudarthrosis within 1 and 2 years ( P = 0.015; P = 0.010), 1-year hardware failure ( P = 0.028), and 2-year reinsertion of instrumentation ( P = 0.009). Reoperation rates for both approaches were not statistically different at any time point throughout the 5-year period. In addition, there were no significant differences in both procedural and 90-day postoperative costs.

CONCLUSIONS

PSO was associated with higher rates of surgical complications compared with anterior approaches. However, there was no significant difference in overall reoperation rates. Spine surgeons should select the optimal technique for a given patient and the type of lordotic correction required.

A comparison of traditional and net structured intersomatic cages in the lombosacral region: A biomechanical analysis for enhancing discopathy treatment

The vertebral column represents an essential element for support, mobility, and the protection of the central nervous system. Various pathologies can compromise these vital functions, leading to pain and a decrease in the quality of life. Within the scope of this study, a novel redesign of the Intersomatic Cage, traditionally used in the presence of discopathy, was proposed. The adoption of additive manufacturing technology allowed for the creation of highly complex geometries, focusing on the lumbosacral tract, particularly on the L4-L5 and L5-S1 intervertebral discs. In addition to the tensile analysis carried out using Finite Element Analysis (FEA) in static simulations, a parallel study on the range of motion (ROM) of the aforementioned vertebral pairs was conducted. The ROM represents the relative movement range between various vertebral pairs. The introduction of the intersomatic cage between the vertebrae, replacing the pulpy nucleus of the intervertebral disc, could influence the ROM, thus having significant clinical implications. For the analysis, the ligaments were modelled using a 1D approach. Their constraint reaction and deformability upon load application were analysed to better understand the potential biomechanical implications arising from the adoption of the cages. During the FEA simulations, two types of cages were analysed: LLIF for L4-L5 and ALIF for L5-S1, subjecting them to four different loading conditions. The results indicate that the stresses exhibited by cages with a NET structure are generally lower compared to those of traditional cages. This stress reduction in cages with NET structure suggests a more optimal load distribution, but it is essential to assess potential repercussions on the surrounding bone structure.

Venous Anomalies Complicating Anterior Lumbar Interbody Fusion Exposures

The effects of anomalous vasculature impeding optimal exposure to an anterior lumbar interbody fusion approach are limited in literature. We present five individual, unique cases of vascular anomalies in patients undergoing two-stage anterior-posterior lumbar interbody fusion. Cases 1, 2, 4, and 5 have yet to be described in literature in context of anterior lumbar interbody fusions. Case 3 presents anomalous vasculature that has only been described in two other case reports. Case 1 presents the right internal iliac vein originating from the left common iliac vein which was transected for L4-L5 vertebral disc exposure. Case 2 presents the left internal iliac vein originating from the right common iliac vein which required an oblique approach. Case 3 presents a duplicated inferior vena cava that was taken into account but did not interfere with the anterior retroperitoneal approach. Case 4 presents large osteophytes adhering to the left common iliac vein which limited safe dissection and mobilization. Case 5 presents the left internal iliac vein with a high takeoff spanning across the L5-S1 vertebral disc space and requiring transection. This case series highlights the need for preoperative imaging and a working detailed knowledge of anatomy to avoid damaging vasculature that can potentially lead to fatal consequences. The information given in this case series should inform both spine and vascular surgeons on proper preoperative planning. To maximize operative efficiency and safety, spine surgeons and vascular surgeons should collaborate to minimize surgical complications.

Moderate sagittal plane deformity patients have similar radiographic and functional outcomes with either anterior or posterior surgery

PURPOSE

This study aimed to compare the functional and radiographic outcomes of two surgical interventions for adult spinal deformity (ASD): anterior lumbar interbody fusion with anterior column realignment (ALIF-ACR) and posterior approach using Smith-Peterson osteotomy with transforaminal lumbar interbody fusion and pedicle screw fixation (TLIF-Schwab2).

METHODS

A retrospective cohort study included 61 ASD patients treated surgically between 2019 and 2020 at a single tertiary orthopedic specialty hospital. Patients were divided into two groups: Group 1 (ALIF-ACR, 29 patients) and Group 2 (TLIF-Schwab2, 32 patients). Spinopelvic radiographic parameters and functional outcomes were evaluated at 3, 6, and 12 months postsurgery.

RESULTS

Perioperative outcomes favored the ALIF-ACR group, with significantly smaller blood loss, shorter hospital stay, and operative time. Radiographic and functional outcomes were similar for both groups; however, the ALIF-ACR group did have a greater degree of correction in lumbar lordosis at 12 months. Complication profiles varied, with the ALIF-ACR group experiencing mostly hardware-related complications, while the TLIF-Schwab2 group faced dural tears, wound dehiscence, and proximal junctional kyphosis. Both groups had similar revision rates.

CONCLUSION

Both ALIF-ACR and TLIF-Schwab2 achieved similar radiographic and functional outcomes in ASD patients with moderate sagittal plane deformity at 1-year follow-up. However, the safety profiles of the two techniques differed. Further research is required to optimize patient selection for each surgical approach, aiming to minimize perioperative complications and reoperation rates in this challenging patient population.

A Comprehensive Review of the Historical Description of Spine Surgery and Its Evolution

Major strides in the advancement of spine surgery came about in the 21st century. However, the extensive history of spine surgery can be traced back to long before this time. A clear description of the journey from a primitive yet accurate understanding of the human musculoskeletal system to today's modern aspects of spinal techniques is lacking. A narrative literature review was conducted to elucidate where spine surgery began and the techniques used that evolved over time. This review was conducted using PubMed and Google Scholar. Search terms used included "history of spine surgery," "evolution of spine surgery," "origins of spine surgery," "history of laminectomy," "history of spinal fusion," "history of lumbar interbody fusion," "minimally invasive spine surgery," and "navigation in spine surgery." We highlight the evolution of the basic understanding of anatomy and non-surgical and surgical techniques, including bracing, laminectomy, discectomy, and spinal fusion. The current evolution and integration of minimally invasive techniques, lumbar interbody fusion techniques, robotics, navigation, and motion preservation are discussed, as these are the major areas of focus for technological advancement. This review presents an overarching synopsis of the events that chronicle the progress made in spine surgery since its conception. The review uniquely contributes to the growing body of literature on the expansion of spine surgery and highlights major events in its history.

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.

A novel less invasive endoscopic-assisted procedure for complete reduction of low-and high-grade isthmic spondylolisthesis performed by anterior and posterior combined approach

PURPOSE

The optimal surgical management of low- and high-grade isthmic spondylolisthesis (LGS and HGS -IS) is debated as well as whether reduction is needed especially for high-grade spondylolisthesis. Both anterior and posterior techniques can be associated with mechanical disadvantages as hardware failure with loss of reduction and L5 injury. We purpose a novel endoscopic-assisted technique (Sled technique, ST) to achieve a complete reduction in two surgical steps: first anteriorly through a retroperitoneal approach to obtain the greatest part of correction and then posteriorly to complete reduction in the same operation.

METHODS

ST efficacy and complications rate were evaluated through a retrospective functional and radiological analysis.

RESULTS

Thirty-one patients, 12 male (38.7%) and 19 female (61.3%), average age: 45.4 years with single level IS underwent olisthesis reduction by ST. Twenty-three IS involved L5 (74.2%), 7 L4 (22.5%) and 1 L3 (3.3%). No intraoperative complications were recorded. One patient required repositioning of a pedicle screw. A significant improvement of functional and radiological parameters (L4-S1 and L5-S1 lordosis) outcomes was recorded (p < 0.001).

CONCLUSION

ST provides a complete reduction in the slippage in LGS and HGS. The huge anterior release as well as the partial reduction in the slippage by the endoscopic-assisted anterior procedure, because of the cage is acting as a "guide rail", facilitate the final posterior reduction, always complete in our series, minimizing mechanical stresses and neurological risks.

CLINICALTRIALS

gov Identifier: NCT03644407.

Correlation of mental health with physical function, pain, and disability following anterior lumbar interbody fusion

BACKGROUND

Studies have demonstrated the influence of preoperative mental health on outcomes following spine surgery, but prior literature has not assessed the influence of mental health at time of outcome survey collection.

METHODS

Patients who underwent elective anterior lumbar interbody fusion (ALIF) were identified from a prospective registry. Patient-reported outcomes (PROs) were collected preoperatively and up to 1 year postoperatively. Mental health measures studied included 12-item Short Form (SF-12) Mental Component Score (MCS) and Patient Health Questionnaire-9 (PHQ-9). Patient-Reported Outcome Measurement Information System-Physical Function (PROMIS-PF), SF-12 Physical Component Score (PCS), visual analog scale (VAS) back and leg pain, and Oswestry Disability Index (ODI) were compared to the mental health measures by Pearson's correlation tests.

RESULTS

A total of 166 patients were included. SF-12 MCS demonstrated positive correlation to PROMIS-PF preoperatively (|r|= 0.379) and at 6 weeks (|r|= 0.387) (p ≤ 0.016, all). SF-12 MCS demonstrated negative correlation to VAS back at 6 months (|r|= 0.359), VAS leg at 6 weeks (|r|= 0.475) and 12 weeks (|r|= 0.422), and ODI up to 6 months postoperatively (|r|= 0.417-0.526) (p ≤ 0.037, all). PHQ-9 negatively correlated with PROMIS-PF at all periods studied (|r|= 0.425-0.587) and SF-12 PCS up to 6 months postoperatively (|r|= 0.367-0.642) (p ≤ 0.016, all). PHQ-9 positively correlated to VAS back at 6 weeks (|r|= 0.408) and 6 months (|r|= 0.411), VAS leg at 6 weeks (|r|= 0.344), and ODI up to 6 months postoperatively (|r|= 0.321-0.669) (p ≤ 0.034, all).

CONCLUSION

Inferior mental health correlated with inferior pain, function, and disability scores at one or more periods postoperatively. This finding was most consistent for correlation between mental health scores and disability. Optimization of mental health may positively influence outcomes, especially regarding disability, following ALIF.

Cerebrospinal fluid (CSF) leak after elective lumbar spinal fusion: Who is at risk?

PURPOSE

CSF leaks are a known complication of lumbar fusion surgery. There is a scarcity of literature describing the incidence and risk factors associated with this complication. The aim of this study was to identify patients who are at risk of developing postoperative CSF leak.

METHODS

The Nationwide Inpatient Sample database was used to identify patients who had lumbar fusion in the US from 2002 to 2014. Inpatient outcomes included the incidence and risk of developing CSF leak based on selected patient-specific characteristics. Secondary outcomes included average length of stay, mean costs, and mortality rates. All statistical analyses were conducted based on multivariate regression models using the SPSS software.

RESULTS

A total of 439,220 patients who underwent elective lumbar fusion procedures were identified. Of these patients, 2.6% (11,636 /439,220) were found to have CSF leak. Independent important risk factors for CSF leak development included: older age (OR: 1.025; 95% CI: 1.02-1.03; p < 0.0001), posterior approach (OR: 1.71; 95% CI: 1.59-1.85; p < 0.0001) compared to anterior approach, chronic deficiency anemia (OR: 1.21; 95% CI:1.14-1.30; p < 0.0001), obesity (OR: 1.22; 95% CI: 1.15-1.30; p < 0.0001), and pulmonary circulatory disease (OR: 1.44; 95% CI: 1.18-1.75; p < 0.0001). CSF leak was associated with increased length of stay (5.39 ± 3.86 vs. 3.74 ± 2.55; p < 0.0001), hospitalization costs (120,129.0 ± 88,123.5 vs. 89,226.8 ± 65,350.3; p < 0.0001) and mortality (0.3% vs. 0.1%; p < 0.05).

CONCLUSION

Spine surgeons should be aware of certain patient and procedure-specific characteristics that increase the risk of developing postoperative CSF leak after lumbar fusion in order to improve patient outcomes.

Trends in Surgical Approach for Single-Level Lumbar Fusion Over the Past Decade

STUDY DESIGN

Retrospective Comparative Study.

OBJECTIVE

The purpose of this study was to characterize trends in surgical approach for single-level lumbar fusion over the past decade.

SUMMARY OF BACKGROUND DATA

The number of elective lumbar fusion cases performed is increasing annually. Several different surgical approaches exist for lumbar spinal fusion including novel anterior approaches developed in recent years. With ongoing innovation, trends in the utilization of common surgical approaches in recent years are unclear.

MATERIALS AND METHODS

A retrospective cohort study was conducted using the PearlDiver database (Fort Wayne, IN). Patients undergoing single-level lumbar fusion between 2010 and 2019 were identified using Current Procedural Technology codes and divided into 4 mutually exclusive cohorts based on surgical approach: (1) anterior-only, (2) anterior approach with posterior instrumentation, (3) posterolateral, and (4) posterior-only interbody. Trend analyses of surgical approach utilization over the last decade were performed with the Cochran-Armitage test to evaluate the 2-tailed null hypothesis that utilization of each surgical approach for single-level lumbar fusion remained constant.

RESULTS

A total of 53,234 patients met inclusion criteria and were stratified into 4 cohorts: anterior-only (n=5104), anterior with posterior instrumentation (n=23,515), posterolateral (n=5525), and posterior-only interbody (n=19,090). Trend analysis revealed the utilization of a posterior-only interbody approach significantly decreased from 36.7% to 29.2% (P<0.001), whereas the utilization of a combined anterior and posterior approach significantly increased from 45.8% to 50.4% (P<0.001). The utilization of an anterior-only approach also significantly increased from 7.9% to 10.5% (P<0.001).

CONCLUSIONS

Utilization of anterior-only and anterior with posterior instrumentation approaches for single-level lumbar fusion have been significantly increasing over the past decade while use of posterior-only interbody approach trended significantly downward. These data may be particularly useful for trainees and spine surgeons as new techniques and technology become available.

LEVEL OF EVIDENCE

Level III-retrospective cohort study.

Successful salvage strategy using anterior retroperitoneal approach in failed posterior lumbar interbody fusion. A retrospective analisys on lumbar lordosis and clinical outcome

OBJECTIVE

Posterior and transforaminal lumbar interbody fusion (PLIF, TLIF) are among the most popular surgical options for lumbar interbody fusion. If non-union occurs with consequent pain and reduced quality of life, revision surgery should correct any previous technical errors, avoiding further complications. The aim of this study was to analyze technical advantages, radiological and clinical outcomes of anterior approaches (ALIF) in case of failed PLIF or TLIF.

METHODS

Retrospective analysis of consecutive patients with persistent low back pain after failed PLIF/TLIF where salvage ALIF through an anterior retroperitoneal miniopen video-assisted technique was performed. Surgical, clinical and radiological data were analysed. Uni and multivariate statistical analysis were applied.

RESULTS

Thirty-six patients (average age: 47.1 years) were included. Mean follow-up was 34.4 months. In 30 patients (83.3%) a posterior surgical step was necessary. Non-union (86.1%), cage migration (5.5%), infection (8.3%) were the causes of revision surgery. In 22 patients (61.1%) the involved level was L5-S1, in 12 patients (33.4%) L4-L5, in 1 patient (2.7%) L3-L4. One patient (2.7%) had two levels (L4-L5 and L5-S1) involved. No major intraoperative complications were recorded. Significant correlation between clinical and radiological outcomes (L4-S1 and L5-S1 lordosis improvement) were observed (postoperative VAS and L5-S1, p = 0.038).

CONCLUSIONS

Salvage ALIF is a safe option that can significantly ameliorate residual pain achieving primary interbody stability with an ideal segmental lordosis according to pelvic parameters. The advantages of a naive anterior approach fulfils the main objectives of a revision surgery in order to significantly increase the chances of definitive fusion.

Endoscopic Techniques for Lumbar Interbody Fusion: Principles and Context

Endoscopic techniques in spine surgery are rapidly evolving, with operations becoming progressively safer and less invasive. Lumbar interbody fusion (LIF) procedures comprise many spine procedures that have benefited from endoscopic assistance and minimally invasive approaches. Though considerable variation exists within endoscopic LIF, similar principles and techniques are common to all types. Nonetheless, innovations continually emerge, requiring trainees and experienced surgeons to maintain familiarity with the domain and its possibilities. We present two illustrative cases of endoscopic transforaminal lumbar interbody fusion with a comprehensive literature review of the different approaches to endoscopic LIF procedures.

Outcomes of anterior vs. posterior approach to single-level lumbar spinal fusion with interbody device: An analysis of the nationwide inpatient sample

BACKGROUND

Interbody devices have revolutionized lumbar spinal fusion surgery by improving mechanical stability and maximizing fusion potential. Several approaches for interbody fusion exist with two of the most common being anterior lumbar interbody fusion (ALIF) and posterior lumbar interbody fusion (PLIF). This study aims to compare patient data, hospital outcomes, and post-operative complications between an anterior vs. posterior approach to lumbar interbody fusion.

METHODS

This retrospective cohort study utilized the Nationwide Inpatient Sample (NIS) and International Classification of Diseases, 10th edition (ICD10) codes to identify patients (18 +) from 2016 to 2018 who underwent lumbar interbody fusion under an anterior or posterior approach. Patients missing identifiers were excluded from this study. Patients were further investigated by demographic data and the presence of comorbidities. Hospital outcome data was investigated by length of stay (LOS), total hospital charges, mortality, and post-operative complications.

RESULTS

373,585 patients were included in this study. 257,975 (69%) underwent fusion via a posterior approach, and 115,610 (31%) via an anterior approach. Patients undergoing posterior approach were found to have a greater number of comorbidities than anterior (3.5 vs. 2, respectively, p = <0.001). The posterior approach was associated with decreased LOS (3.59 vs 4.19 days, p = <0.0001) and decreased total hospital charges ($141,700 vs $211,015, p = <0.0001). A posterior approach was found to have lower rates of post-operative complications. For the anterior approach cohort, tobacco dependence (OR=1.31 [1.20-1.42, p = <0.001], diabetes (OR=2.41 [2.33-2.49, p = <0.001], and osteoporosis (OR=1.42 [1.30-1.54, p = <0.001] were found to be significant independent predictors of post-operative pseudoarthrosis. Obesity (OR=1.28 [1.14-1.42, p = <0.001], tobacco dependence (OR=1.48 [1.40-1.56, p = <0.001], diabetes (OR=2.21 [2.10-2.32, p = <0.001], congestive heart failure (OR=1.20 [1.01-1.39, p = 0.04], and osteoporosis (OR=1.65 [1.55-1.75, p = <0.001], were found to be independent predictors of post-operative pseudoarthrosis in the posterior cohort.

CONCLUSIONS

Patients who underwent the anterior approach suffered from increased hospital charges, length of stay, and increased risk of post-operative complications including mortality, wound dehiscence, hematoma/seroma, and pseudoarthrosis. Comorbid disease plays a significant role in the outcome of successful fusion with variable effect depending on the surgical approach. Increasing due diligence in patient selection should be considered when choosing an approach in pre-operative planning.

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.

Venous anatomy of the lumbar region applied to anterior lumbar interbody fusion (ALIF): Proposal of a new classification

Background

Anterior lumbar interbody fusion (ALIF) is a good alternative for the surgical treatment of lumbar degenerative disc disease. The primary vascular complications regarding this intervention involve the common iliac vein bifurcation complex (CIVC). Currently, no classification system allows defining which patients are more prone to these complications. We aimed to perform a retrospective study evaluating the anatomy of the common iliac CIVC at the L5-S1 disc proposing a novel classification system as it relates to the ALIF difficulty.

Methods

91 consecutive patients who underwent ALIF at the L5-S1 level were included. We categorize the CIVC at the L5-S1 disc space into four types according to the veins position along the disc space. The patient records were reviewed for demographic information, surgical characteristics, and complications. The surgical difficulty was rated at the end of the procedure.

Results

54% of the patients were women. The mean age was 52.5 ± 14.8 years. Mean surgical bleeding was 152 ml (range 20ml -3000 ml), and mean surgical time was 79 ± 13.3 minutes. Berbeo-Diaz-Vargas (BDV) classification type 4 was found in 43.9% of the patients. The surgical complexity was associated with the bleeding magnitude and surgical time spent (p<0.01), not being related to the corporal mass index or sacral slope. Bleeding magnitude, surgical time, and surgical complexity were significantly related to the BDV classification system (p<0.01). Weighted Cohen´s kappa index for the BDV scale was 0.89 (95% IC 0.822 – 0.974).

Conclusions

BDV scale is a reliable and reproducible tool for the classification of CIVC significantly related to a higher incidence of bleeding, prolonged operating time, and increased perceived difficulty by the surgeon.

Iatrogenic effects of radical cancer surgery on male fertility

Iatrogenic causes of male infertility can include medications, chemotherapy, radiation, and surgery. In this review, we discuss commonly performed urologic cancer surgeries and nonurologic surgeries that harbor a high risk of iatrogenic infertility. These include radical prostatectomy, radical cystectomy, retroperitoneal lymph node dissection, pelvic colon surgery, and anterior spine surgery. In addition, we review the anatomy and surgical strategies that help to reduce the risks of infertility. With an increase in life expectancy and improvements in fertility preservation, it is important to properly counsel patients about the risks of infertility and provide options for fertility preservation before surgery.

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.

State of the art advances in minimally invasive surgery for adult spinal deformity

Adult spinal deformity (ASD) can be associated with substantial suffering due to pain and disability. Surgical intervention for achieving neural decompression and restoring physiological spinal alignment has shown to result in significant improvement in pain and disability through patient-reported outcomes. Traditional open approaches involving posterior osteotomy techniques and instrumentation are effective based on clinical outcomes but associated with high complication rates, even in the hands of the most experienced surgeons. Minimally invasive techniques may offer benefit while decreasing associated morbidity. Minimally invasive surgery (MIS) for ASD has evolved over the past 20 years, driven by improved understanding of open procedures along with novel technique development and technologic advancements. Early efforts were hindered due to suboptimal outcomes resulting from high pseudarthrosis, inadequate correction, and fixation failure rates. To address this, multi-center collaborative groups have been established to study large numbers of ASD patients which have been vital to understanding optimal patient selection and individualized management strategies. Different MIS decision-making algorithms have been described to better define appropriate candidates and interbody selection approaches in ASD. The purpose of this state of the review is to describe the evolution of MIS surgery for adult deformity with emphasis on landmark papers, and to discuss specific MIS technology for ASD, including percutaneous pedicle screw instrumentation, hyperlordotic grafts, three-dimensional navigation, and robotics.

The History of Anterior and Lateral Approaches to the Lumbar Spine

Anterior and lateral approaches to the lumbar spine are commonly used today for a variety of indications. These approaches can ultimately be traced back to early attempts to treat Pott's disease. Evidence of Mycobacterium tuberculosis infection of the spine dates as far back as 2400 BCE, with ancient Egyptian mummies exhibiting lesions consistent with Pott's disease. For many centuries, Pott's disease was treated conservatively, and surgery came to be used when conservative therapy was ineffective, as medical therapy had yet to become available. In 1779, Percivall Pott recommended that peripheral paraspinal tuberculous abscesses be drained after noticing that patients' lower limb function improved after the formation of spontaneous draining sinuses. Building on Pott's ideas, Ménard described the first lateral approach to the spine via a costotransversectomy approximately 1 century after Pott's theory. Most importantly, the surge in understanding anatomy with respect to developing safe corridors to the deeper structures of the human body brought together advances in technology, instrumentation, and visualization. Surgeons were thus emboldened to explore more complex anterior approaches to the spine. In 1906, Müller reported the first successful anterior approach to the spine in a patient with Pott's disease. Over the next several decades, the efforts of surgeons such as Ito, Capener, Burns, and Mercer would lead to the development of the anterior lumbar interbody fusion. The costotransversectomy later evolved into the lateral rhachotomy and lateral extracavitary approach, which along with advances in the anterior lumbar interbody fusion paved the way for the oblique lumbar interbody fusion and lateral lumbar interbody fusion.

ALIF in the correction of spinal sagittal misalignment. A systematic review of literature

PURPOSE

We aim at analysing the impact of anterior lumbar interbody fusion (ALIF) in restoring the main spinopelvic parameters, along with its potentials and limitations in correcting sagittal imbalance.

MATERIALS AND METHODS

The 2009 PRISMA flow chart was used to systematically review the literature; 27 papers were eventually selected. The following spinopelvic parameters were observed: pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), segmental lumbar lordosis (LLseg) and sagittal vertical axis (SVA). Papers reporting on hyperlordotic cages (HLC) were analysed separately. The indirect decompression potential of ALIF was also assessed. The clinical outcome was obtained by collecting visual analogue scale (VAS) for back and leg pain and Oswestry Disability Index (ODI) scores. Global fusion rate and main complications were collected.

RESULTS

PT, SS, LL, LLseg and SVA spinopelvic parameters all improved postoperatively by - 4.3 ± 5.2°, 3.9 ± 4.5°, 10.6 ± 12.5°, 6.7 ± 3.5° and 51.1 ± 44.8 mm, respectively. HLC were statistically more effective in restoring LL and LLseg (p < 0.05). Postoperative disc height, anterior disc height, posterior disc height and foraminal height, respectively, increased by 58.5%, 87.2%, 80.9% and 18.1%. Postoperative improvements were observed in VAS back and leg and ODI scores (p < 0.05). The global fusion rate was 94.5 ± 5.5%; the overall complication rate was 13%.

CONCLUSION

When managing sagittal imbalance, ALIF can be considered as a valid technique to achieve the correct spinopelvic parameters based on preoperative planning. This technique permits to obtain an optimal LL distribution and a solid anterior column support, with lower complications and higher fusion rates when compared to posterior osteotomies.

Functional and radiological outcome of anterior retroperitoneal versus posterior transforaminal interbody fusion in the management of single-level lumbar degenerative disease

OBJECTIVE

In this study the authors compared the anterior lumbar interbody fusion (ALIF) and posterior transforaminal lumbar interbody fusion (TLIF) techniques in a homogeneous group of patients affected by single-level L5–S1 degenerative disc disease (DDD) and postdiscectomy syndrome (PDS). The purpose of the study was to analyze perioperative, functional, and radiological data between the two techniques.

METHODS

A retrospective analysis of patient data was performed between 2015 and 2018. Patients were clustered into two homogeneous groups (group 1 = ALIF, group 2 = TLIF) according to surgical procedure. A statistical analysis of clinical perioperative and radiological findings was performed to compare the two groups. A senior musculoskeletal radiologist retrospectively revised all radiological images.

RESULTS

Seventy-two patients were comparable in terms of demographic features and surgical diagnosis and included in the study, involving 32 (44.4%) male and 40 (55.6%) female patients with an average age of 47.7 years. The mean follow-up duration was 49.7 months. Thirty-six patients (50%) were clustered in group 1, including 31 (86%) with DDD and 5 (14%) with PDS. Thirty-six patients (50%) were clustered in group 2, including 28 (78%) with DDD and 8 (22%) with PDS. A significant reduction in surgical time (107.4 vs 181.1 minutes) and blood loss (188.9 vs 387.1 ml) in group 1 (p < 0.0001) was observed. No significant differences in complications and reoperation rates between the two groups (p = 0.561) was observed. A significant improvement in functional outcome was observed in both groups (p < 0.001), but no significant difference between the two groups was found at the last follow-up. In group 1, a faster median time of return to work (2.4 vs 3.2 months) was recorded. A significant improvement in L5–S1 postoperative lordosis restoration was registered in the ALIF group (9.0 vs 5.0, p = 0.023).

CONCLUSIONS

According to these results, interbody fusion is effective in the surgical management of discogenic pain. Even if clinical benefits were achieved earlier in the ALIF group (better scores and faster return to work), both procedures improved functional outcomes at last follow-up. The ALIF group showed significant reduction of blood loss, shorter surgical time, and better segmental lordosis restoration when compared to the TLIF group. No significant differences in postoperative complications were observed between the groups. Based on these results, the ALIF technique enhances radiological outcome improvement in spinopelvic parameters when compared to TLIF in the management of adult patients with L5–S1 DDD.

Hybrid Minimally Invasive Technique for Treatment of Thoracolumbar Spondylodiscitis and Vertebral Osteomyelitis

OBJECTIVE

Spondylodiscitis and vertebral osteomyelitis cause significant morbidity and mortality, and typically occur in patients with multiple comorbidities. The use of minimally invasive spinal surgery in the previous decade has offered the advantages of reduced intraoperative blood loss and postoperative pain for patients. In the present report, we have described our experience with using a hybrid minimally invasive (HMI) technique (combining percutaneous fixation with a mini-open approach for decompression and debridement) for the treatment of thoracolumbar spondylodiscitis, reporting the patient demographics, intraoperative measures, and 12-month outcomes.

METHODS

The data from patients presenting to a tertiary referral neurosurgical center with thoracolumbar spondylodiscitis and osteomyelitis who had undergone HMI from 2016 to 2018 were retrospectively evaluated. Patient demographics, intraoperative factors, estimated blood loss, and immediate postoperative complications were recorded. The patient outcomes were evaluated using EuroQOL 5-dimension questionnaire and visual analog scale in the immediate postoperative period and at 12 months postoperatively.

RESULTS

A total of 13 patients were included in the present study, 12 with spontaneous infection and 1 with infection secondary to recent microdiscectomy at another institution. All the patients had systemic comorbidities with an American Society of Anesthesiologists class of ≥2. Of the 13 patients, 11 had pyogenic infections and 2 had spinal tuberculosis. The mean estimated blood loss was 546.2 mL. The mean time for patients to sit out of bed was 2.2 days, and the mean time to start mobilizing was 4.5 days. The EuroQOL 5-dimension questionnaire scores showed improvement in all modalities at 12 months postoperatively.

CONCLUSIONS

In our cohort, HMI was a safe and effective treatment of thoracolumbar spondylodiscitis, with the potential benefits of reduced blood loss, operative duration, and postoperative pain.