Access related complications in anterior lumbar surgery performed by spinal surgeons

Predictors of inpatient admission in the setting of anterior lumbar interbody fusion: a Minimally Invasive Spine Study Group (MISSG) investigation

OBJECTIVE

While the anterior lumbar interbody fusion (ALIF) procedure may be amenable to ambulatory surgery, it has been hypothesized that limitations such as the risk of postoperative ileus and vascular complications have hindered transition of this procedure to the outpatient setting. Identification of independent risk factors predisposing patients to inpatient stays of ≥ 24 hours after ALIF may facilitate better postsurgical outcomes, target modifiable risk factors, and assist in the development of screening tools to transition appropriate patients to the ambulatory surgery center (ASC) setting for this procedure. The purpose of this study was to identify the most relevant risk factors that predispose patients to ≥ 24-hour admission following ALIF.

METHODS

A prospectively maintained surgical registry was reviewed for patients undergoing single ALIF between May 2006 and December 2019. Demographics, preoperative diagnosis, perioperative variables, and postoperative complications were evaluated according to their relative risk (RR) elevation for an inpatient stay of ≥ 24 hours. A Poisson regression model was used to evaluate predictors of inpatient stays of ≥ 24 hours. Risk factors for inpatient admission of ≥ 24 hours were identified with a stepwise backward regression model.

RESULTS

A total of 111 patients underwent single-level ALIF (50.9% female and 52.6% male, ≤ 50 years old). Eleven (9.5%) patients were discharged in < 24 hours and 116 remained admitted for ≥ 24 hours. The average inpatient stay was > 2 days (53.7 hours). The most common postoperative complications were fever (body temperature ≥ 100.4°F; n = 4, 3.5%) and blood transfusions (n = 4, 3.5%). Bivariate analysis revealed a preoperative diagnosis of retrolisthesis or lateral listhesis to elevate the RR for an inpatient stay of ≥ 24 hours (RR 1.11, p = 0.001, both diagnoses). Stepwise multivariate analysis demonstrated significant predictors for inpatient stays of ≥ 24 hours to be an operation on L4-5, coexisting degenerative disc disease (DDD) with foraminal stenosis, and herniated nucleus pulposus (RR 1.11, 95% CI 1.03-1.20, p = 0.009, all covariates).

CONCLUSIONS

This study provides data regarding the incidence of demographic and perioperative characteristics and postoperative complications as they pertain to patients undergoing single-level ALIF. This preliminary investigation identified the most relevant risk factors to be considered before appropriately transitioning ALIF procedures to the ASC. Further studies of preoperative characteristics are needed to elucidate ideal ASC ALIF patients.

Thoracic gout tophus with abdominal wall protrusion: A case report

RATIONALE

A patient presented the abdominal wall protrusion due to tophaceous gout of the spine. Similar cases were not reported in the literature. This study aimed to report a case of tophaceous gout of the spine with abdominal wall protrusion.

PATIENT CONCERNS

A 38-year-old male patient had a 10-year history of gout and hyperuricemia. He complained of back pain and abdominal wall protrusion.

DIAGNOSES

The patient was diagnosed with tophaceous gout of the spine with abdominal wall weakness caused by T11 nerve root compression.

INTERVENTIONS

A semi-lamina decompression was performed at T11-T12. The pathological examination of the specimen demonstrated tophaceous gout of the spine.

OUTCOMES

After the surgery, the patient's back pain was completely relieved and the abdominal wall weakness significant improved.

LESSONS

This case highlighted that axial gout could mimic thoracic disk herniation clinically. The abdominal wall weakness might also be due to single T11 nerve compression by the tophaceous gout of the spine. In patients with a history of gout, axial gout should be considered as one of the differential diagnoses.

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.

One-stage Debridement via Oblique Lateral Interbody Fusion Corridor Combined with Posterior Pedicle Screw Fixation in Treating Spontaneous Lumbar Infectious Spondylodiscitis: A Case Series

Objective

Surgery is indicated when antibiotic treatment fails in pyogenic spondylodiscitis, which is caused by pathogens such as the Staphylococcus species. The aim of the present study was to investigate the efficacy and safety of the oblique lateral interbody fusion (OLIF) corridor approach combined with posterior pedicle screw fixation for treating pyogenic spondylodiscitis.

Methods

This was a retrospective case series study. A total of 11 patients with an average age of 60.7 years (range, 40–70 years; 10 males and 1 females) with lumbar pyogenic spondylodiscitis who underwent single‐stage debridement and reconstruction using the OLIF corridor combined with posterior pedicle screw fixation were recruited in our study from June 2016 to July 2017. All patients had single‐level pyogenic spondylodiscitis between T₁₂ and L₅. The baseline data, perioperative outcomes (operative time, intra‐operative blood loss, and intra‐operative complication), postoperative laboratory tests (erythrocyte sedimentation rate [ESR], C‐reactive protein [CRP], white blood count [WBC], and tissue culture results), long‐term complications (recurrence, fixation failure, and bony non‐fusion rates), and duration of antibiotic administration were reviewed. Outcomes evaluated using a variety of scales including visual analog scale (VAS) score and Oswestry disability index (ODI), were compared pre‐operatively and post‐operatively.

Results

The mean follow‐up period of time was 18.3 months. The average operative time and intra‐operative blood loss were 217.0 ± 91.91 min and 220.9 ± 166.10 mL, respectively. There were no intra‐operative complications, except in 1 patient who encountered somatosensory evoked potentials changes and 1 patient who had motor evoked potentials changes, both without post‐surgery neurological deficits. Causative organisms were identified in 4 patients: Staphylococcus aureus in 1 patient and Streptococcus in 3 patients. At approximately 8.8 weeks after surgery, WBC, CRP, and ESR had returned to normal levels. All patients were pain free with no recurring infection. There was no fixation failure during follow up. Solid bony fusions were observed in all cases within 6 months. At the final follow up, the mean VAS (0.6 ± 0.69) and ODI (14.4 ± 4.27) were significantly lower than those before surgery (P < 0.05).

Conclusion

One‐stage debridement with autogenous iliac bone graft through the OLIF corridor combined with posterior pedicle screw fixation is effective and safe for single‐level spontaneous lumbar pyogenic spondylodiscitis after antibiotic treatment fails.

Anatomical Evaluation of Lumbar Arteries for Lateral Lumbar Interbody Fusion with Magnetic Resonance Imaging

Introduction

Lateral lumbar interbody fusion (LLIF) is becoming a more common surgical treatment option for adult degenerative lumbar conditions. LLIF is a mini-open access technique with wound retractors, and postoperative hematoma due to segmental vessels injury is reported. Thus, it is considered that there is a need to conduct detailed preoperative examinations to identify where the lumbar vessels are. As far as we know, there are only a few studies investigating the location of the lumbar arteries. This study evaluates the anatomical position of lumbar arteries using magnetic resonance imaging (MRI).

Methods

We studied 101 MRIs of patients with lumbar disease. The length from the upper and lower end plates of the vertebra to the lumbar arteries was measured. The measurement was conducted with coronal MRI images of every quarter slice of L1 to L4 vertebrae. We also investigated sagittal MRI images to determine whether the lumbar vessels are located on intervertebral disc in each level from L1/2 to L5/S1.

Results

The lumbar vessels are not always located at the center of the vertebrae. Some lumbar vessels are located within 8 mm from the end plates. Especially in L4, the lumbar vessels tended to go down from the anterior cranial side to the posterior caudal side (P < 0.01). 8, 24, and 54 lumbar vessels are located at the anterior quarter, the center, and the posterior quarter slice of the vertebrae, respectively, in L4. There were seven lumbar vessels in total located on the vertebral disc level.

Conclusions

It is necessary to investigate where the lumbar arteries are located to prevent its injury in LLIF, because the lumbar artery is not always located at the center of a vertebra. MRIs may provide a valuable information to avoid vascular injury during LLIF.

Perforated ileus after L5-S1 anterior lumbar interbody fusion: a case report presentation

Acute colonic pseudo-obstruction (ACPO) as a result of anterior lumbar spinal surgery can result in colonic perforation. ACPO is often treated successfully with conservative measures, reserving surgical intervention for severe cases. The most severe cases can result in colonic perforation with a concomitant high mortality rate. Herein we outline a case of a 72-year-old male with multiple medical comorbidities and history of intermittent constipation who underwent anterior lumbar interbody fusion (ALIF) of L5-S1. The patient's multiple medical comorbidities placed him at risk for ACPO. His postoperative course was complicated by an ileus. The patient initially underwent conservative management that failed, resulting in colonic perforation. He underwent urgent exploratory laparotomy and repair of colonic perforation by the general surgery service. The patient had spontaneous return of bowel function on postoperative day 5, and at 6 months, he was doing well. The main purpose of this case report is to present a unique case of colonic perforation after ALIF. Understanding patient risk factors can help in early identification and treatment of potentially life-threatening complications. Surgeons should discuss the possibility of this complication with the patient during surgical counseling for anterior lumbar surgery.

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.

Analysis of the Functional and Radiological Outcomes of Lumbar Decompression without Fusion in Patients with Degenerative Lumbar Scoliosis

STUDY DESIGN

Retrospective study.

PURPOSE

This study aimed to analyze the functional and radiological outcomes of lumbar decompression in patients with degenerative lumbar scoliosis (DLS).

OVERVIEW OF LITERATURE

Patients with DLS have symptoms related to lumbar canal stenosis (LCS) and those due to compensated spinal imbalance. Whether the deformity is the cause of pain or is an adaptive change for the ongoing LCS remains debatable. The extensive surgery for deformity correction along with spinal fusion is reported to have high perioperative morbidity and complication rate.

METHODS

This retrospective analysis involved 51 patients who underwent lumbar decompression for LCS associated with DLS from October 2006 to October 2016. The magnitude of the curve was determined using Cobb's angle and lumbar lordosis (D12-S1) on the preoperative and final follow-up, respectively. The Visual Analog Scale (VAS) and modified Oswestry Disability Index (mODI) scores at the preoperative and final follow-up indicated the functional outcome. Statistical analyses were performed using Student t -test.

RESULTS

All 51 patients were included in the statistical analyses. The mean patient age at presentation was 63.88±7.21 years. The average follow-up duration was 48±18.10 months. The average change in the Cobb's angle at the final follow-up was statistically insignificant (1°±1.5°, p=0.924; 20.8°±5.1° vs. 21.9°±5.72°). The mean change in lumbar lordosis at the final follow-up was statistically insignificant (3.29°±1.56°, p=0.328; 30.2°±7.9° vs. 27.5°±7.1°). There was statistically insignificant worsening in the back VAS scores at the final follow-up (4.9±1.9 vs. 6.0±1.2, p=0.07). There was statistically significant improvement in the leg pain component of the VAS score at the final follow-up (5.8±1.05 vs. 2.6±1.2, p<0.001). There was statistically significant improvement in the mODI scores at the final follow-up (p<0.001).

CONCLUSIONS

Lumbar decompression in DLS is associated with good functional outcome, especially when the symptoms are related to LCS. Curve progression following lumbar decompression is very less at mid-term and is similar to that in the natural course of the disease.

Percutaneous fixation of thoracolumbar vertebral fractures

Surgical treatment of patients with thoracolumbar vertebral fracture without neurological deficit is still controversial.

Management of vertebral fracture with percutaneous fixation was first reported in 2004.

Advantages of percutaneous fixation are: less tissue dissection; decreased post-operative pain; decreased bleeding and operative time (depending on the steep learning curve); better screw positioning with fluoroscopy compared with an open freehand technique; and a decreased infection rate.

The limitations of percutaneous fixation of vertebral fractures include increased radiation exposure to the patient and the surgeon, together with the steep learning curve for this technique.

Adding a screw at the level of the fractured vertebra has the advantages of incorporating fewer motion segments with less operative time and bleeding. This also increases the axial, sagittal and torsional stiffness of the construct.

Percutaneous fixation alone without grafting is sufficient for treating type A and B1 (AO classification) thoracolumbar fractures with satisfactory results concerning kyphosis reduction when compared with open instrumentation and fusion and with open fixation.

Type C and B2 fractures (ligamentous injuries) should undergo fusion since the ligamentous healing is mechanically weak, increasing the risk of instability.

This review offers a detailed description of percutaneous screw insertion and discusses the advantages and disadvantages.

Cite this article: EFORT Open Rev 2018;3:604-613. DOI: 10.1302/2058-5241.3.170026.

Chiripa technique. Report of a novel technique to protect the spinal cord from incidental durotomies during complex spinal procedures

BACKGROUND CONTEXT

Incidental durotomy is the most frequent intraoperative complication reported in spinal literature. Multiple strategies have been suggested to manage it.

METHODS

A brief technical report.

DISCUSSION

The use of cottonoids is a recommended measure to avoid incidental durotomies during spinal surgeries; thus, ventral protection might be difficult to achieve. This "Chiripa technique" provides circumferential protection to the neurostructures, so that surgical procedures can be safely carried out.

CONCLUSION

Taking into account the low costs and ease of execution, this can be a valuable tip that may widely extended in all cases where a circumferential dural protection is needed.

Anterior Lumbar Fusion: Differences in Patient Selection and Surgical Outcomes Between Neurosurgeons and Orthopaedic Surgeons

OBJECTIVE

Anterior lumbar fusion (ALF) is performed by both neurosurgeons and orthopaedic surgeons. The aim of this study was to determine differences between the 2 surgical subspecialties in terms of patient selection and postoperative outcomes after ALF.

METHODS

A retrospective cohort study of adult patients undergoing ALF in the American College of Surgeons National Surgical Quality Improvement Program database from 2010 to 2014 was performed. Univariate analyses were performed to identify differences in baseline patient demographics, comorbidities, operative characteristics, and 30-day postoperative outcomes between neurosurgery and orthopaedic surgery patients. Multivariate logistic regression analysis was used to determine whether surgical subspecialty was an independent risk factor for postoperative complications.

RESULTS

The study included 3182 patients, with 1629 (51.2%) neurosurgery patients and 1553 (48.8%) orthopaedic surgery patients. A greater proportion of neurosurgery patients were >65 years old, were being treated with preoperative steroids, had cardiac or pulmonary comorbidities, and had an American Society of Anesthesiologists classification III or higher. ALF procedures performed by neurosurgeons more frequently involved use of intervertebral devices and bone graft. On multivariate logistic regression analysis, ALF procedures performed by neurosurgeons were independently associated with a higher risk of reoperation (odds ratio = 1.61; 95% confidence interval, 1.02-2.56; P = 0.042) and urinary tract infection (odds ratio = 1.94; 95% confidence interval, 1.02-3.68; P = 0.043).

CONCLUSIONS

In addition to differences in baseline patient demographics and comorbidities and operative characteristics, ALF performed by neurosurgeons had a higher risk of 30-day reoperation and urinary tract infection compared with ALF performed by orthopaedic surgeons.

Use of an Alternative Surgical Corridor in Oblique Lateral Interbody Fusion at the L5-S1 Segment: A Technical Report

STUDY DESIGN

Technical report.

OBJECTIVE

To demonstrate the use of an alternative surgical corridor in oblique lateral interbody fusion (OLIF) at the L5-S1 segment.

SUMMARY OF BACKGROUND DATA

OLIF L5-S1 is essentially performed through the central disk space between the bifurcations of the iliac vessels, which is sometimes difficult due to the vascular structures that obstruct the surgical field. Another concern is retrograde ejaculation following superior hypogastric plexus injury in male patients.

MATERIALS AND METHODS

The alternative surgical corridor involves the lateral disk space external to the left iliac vessels. The patient position and the retroperitoneal approach are similar to those used in the conventional OLIF L5-S1. The left iliac vessels are identified and mobilized medially to the midline of the L5-S1 disk space. The vascular structures are then protected using the conventional OLIF 51 retractor system.

RESULTS

Six patients underwent OLIF L5-S1 through the alternative lateral surgical corridor. The L5-S1 disk spaces were always exposed sufficiently for disk preparation and cage insertion. The postoperative radiographs showed a satisfactory L5-S1 reconstruction with good cage position. There were no perioperative complications during the surgical access and reconstruction procedures.

CONCLUSIONS

When the central approach to the L5-S1 disk space poses a risk of vascular or superior hypogastric plexus injury, use of a lateral approach external to the left iliac vessels can be an alternative method to perform OLIF L5-S1.

A UK-based pilot study of current surgical practice and implant preferences in lumbar fusion surgery

Lumbar fusion surgery is an established procedure for the treatment of low back pain. Despite the wide set of alternative fusion techniques and existing devices, uniform guidelines are not available yet and common surgical trends are scarcely investigated.The purpose of this UK-based study was to provide a descriptive portrait of current surgeons' practice and implant preferences in lumbar fusion surgery.A UK-based in-person survey was designed for this study and submitted to a group of consultant spinal surgeons (n = 32). Fifteeen queries were addressed based on different aspects of surgeons' practice: lumbar fusion techniques, implant preferences, and bone grafting procedures. Answers were analyzed by means of descriptive statistics.Thirty-two consultant spinal surgeons completed the survey. There was clear consistency on the relevance of a patient-centered management (82.3%), along with a considerable variability of practice on the preferred fusion approach. Fixation surgery was found to be largely adopted (96.0%) and favored over stand-alone cages. With regards to the materials, titanium cages were the most used (54.3%). The geometry of the implants influenced the choice of lumbar cages (81.3%). Specifically, parallel-shape cages were mostly avoided (89.2%) and hyperlordotic cages were preferred at the lower lumbar levels. However, there was no design for lumbar cages which was consistently favored. Autograft bone graft surgeries were the most common (60.0%). Amongst the synthetic options, hydroxyapatite-based bone graft substitutes (76.7%) in injectable paste form (80.8%) were preferred.Current lumbar fusion practice is variable and patient-oriented. Findings from this study highlight the need for large-scale investigative surveys and clinical studies aimed to set specific guidelines for certain pathologies or patient categories.

Sexual activity after spine surgery: a systematic review

INTRODUCTION

Sexual function is an important determinant of quality of life, and factors such as surgical approach, performance of fusion, neurological function and residual pain can affect it after spine surgery. Our aim was to perform a systematic review to collate evidence regarding the impact of spine surgery on sexual function.

METHODS

A systematic review of studies reporting measures of sexual function, and incidence of adverse sexual outcomes (retrograde ejaculation) after major spine surgery was done, regardless of spinal location. Pubmed (MEDLINE) and Google Scholar databases were queried using the following search words "Sex", "Sex life", "Sexual function", "Sexual activity", "retrograde ejaculation", "Spine", "Spine surgery", "Lumbar surgery", "Lumbar fusion", "cervical spine", "cervical fusion", "Spinal deformity", "scoliosis" and "Decompression". All articles published between 1997 and 2017 were retrieved from the database. A total of 81 studies were included in the final review.

RESULTS

Majority of the studies were retrospective case series and were low quality (Level IV) in evidence. Anterior lumbar approaches were associated with a higher incidence of retrograde ejaculation, especially with the utilization of transperitoneal laparoscopic approach. There is inconclusive evidence on the preferred sexual position following fusion, and also on the impact of BMP-2 usage on retrograde ejaculation/sexual dysfunction.

CONCLUSION

Despite limited evidence from high-quality articles, there is a general trend towards improvement of sexual activity and function after spine surgery. Future studies incorporating specific assessments of sexual activity will be required to address this important determinant of quality of life so that appropriate pre-operative counselling can be done by providers. These slides can be retrieved under Electronic Supplementary Material.

We Need to Talk about Lumbar Total Disc Replacement

BACKGROUND

Replacement of a diseased lumbar intervertebral disc with an artificial device, a procedure known as lumbar total disc replacement (LTDR), has been practiced since the 1980s.

METHODS

Comprehensive review of published literature germane to LTDR, but comment is restricted to high-quality evidence reporting implantation of lumbar artificial discs that have been commercially available for at least 15 years at the time of writing and which continue to be commercially available.

RESULTS

LTDR is shown to be a noninferior (and sometimes superior) alternative to lumbar fusion in patients with discogenic low back pain and/or radicular pain attributable to lumbar disc degenerative disease (LDDD). Further, LTDR is a motion-preserving procedure, and evidence is emerging that it may also result in risk reduction for subsequent development and/or progression of adjacent segment disease.

CONCLUSIONS

In spite of the substantial logistical challenges to the safe introduction of LTDR to a health care facility, the procedure continues to gain acceptance, albeit slowly.

CLINICAL RELEVANCE

Patients with LDDD who are considering an offer of spinal surgery can only provide valid and informed consent if they have been made aware of all reasonable surgical and nonsurgical options that may benefit them. Accordingly, and in those cases in which LTDR may have a role to play, patients under consideration for other forms of spinal surgery should be informed that this valid procedure exists.

Rational decision making in a wide scenario of different minimally invasive lumbar interbody fusion approaches and devices

With the proliferation of a variety of modern MIS spine surgery procedures, it is mandatory that the surgeon dominate all aspects involved in surgical indication. The information related to the decision making in patient selection for specific procedures is mandatory for surgical success. The objective of this study is to present decision-making criteria in minimally invasive surgery (MIS) selection for a variety of patients and pathologies. In this article, practicing surgeons who specialize in various MIS approaches for spinal fusion were engaged to provide expert opinion and literature review on decision making criteria for several MIS procedures. Pros, cons, relative limitations, and case examples are provided for patient selection in treatment with MIS posterolateral fusion (MIS-PLF), mini anterior lumbar interbody fusion (mini-ALIF), lateral interbody fusion (LLIF), MIS posterior lumbar interbody fusion (MIS-PLIF) and MIS transforaminal lumbar interbody fusion (MIS-TLIF). There is a variety of aspects to consider when deciding which modern MIS surgical approach is most appropriate to use based on patient and pathologic characteristics. The surgeon must adapt them to the characteristic of each type of patients, helping them to choose the most effective and efficient therapeutic option for each case.

Minimally invasive anterior, lateral, and oblique lumbar interbody fusion: a literature review

Lumbar interbody fusion involves insertion of a structural graft into an intervertebral disc space to promote bony arthrodesis. It is a well-established surgical strategy for multiple spinal disorders ranging from degenerative conditions to trauma, neoplastic diseases, and deformities requiring correction. Since the inception of lumbar interbody fusion, the most established techniques have been two posterior approaches, the posterior lumbar interbody fusion (PLIF) and the transforaminal lumbar interbody fusion (TLIF). Within the past 15 years, multiple anterolateral approaches to the spine have become widely adopted. These approaches can be performed minimally invasively and spare disruption of the paraspinal muscles and posterior spinal column while enabling wide exposure of the disc space for insertion of interbody grafts much larger than PLIF and TLIF instrumentation. This review highlights three minimally invasive anterolateral approaches: the anterior lumbar interbody fusion (ALIF), the transpsoas lateral lumbar interbody fusion (LLIF), and prepsoas or anterior to the psoas oblique lumbar interbody fusion (OLIF). Relevant topics for discussion and comparison include patient selection, surgical techniques, outcomes, and complications for the three surgical approaches.

Outcomes of oblique lateral interbody fusion for degenerative lumbar disease in patients under or over 65 years of age

Background

Oblique lateral interbody fusion (OLIF) offers the solution to problems of anterior lumbar interbody fusion (ALIF) and lateral lumbar interbody fusion (LLIF). However, OLIF technique for degenerative spinal diseases of elderly patients has been rarely reported. The objective of this study was to determine the clinical and radiological results of OLIF technique for degenerative spinal diseases in patients under or over 65 years of age.

Methods

Sixty-three patients who underwent OLIF procedure were enrolled, including 29 patients who were less than 65 years of age and 34 patients who were over 65 years of age. Fusion rate, change of disc height and lumbar lordotic angle, Numeric Rating Scale (NRS), return to daily activity, patient’s satisfaction rate (PSR), and Oswestry disability index (ODI) were used to assess clinical and functional outcomes.

Results

The mean NRS scores for back and leg pain decreased, respectively, from 4.6 and 5.9 to 2.3 and 1.8 in the group A (less than 65 years) and from 4.5 and 6.8 to 2.6 and 2.2 in the group B (over 65 years) at the final follow-up period. The mean ODI scores improved from 48.4 to 24.0% in the group A and from 46.5 to 25.2% in the group B at the final follow-up period. In both groups, the NRS and ODI scores significantly changed preoperatively to postoperatively (p <  0.001). However, statistical analysis yielded no significant difference in postoperative NRS/ODI scores between two groups. In both groups, the changes in the disc height, segmental lordosis, and fusion rate between the preoperative and postoperative periods were significant. The amount of change between preoperative and postoperative disc height, segmental lordosis, and whole lumbar lordosis demonstrated significant intergroup differences (p <  0.05). Overall perioperative complications occurred in 8 of 29 (27.6%) patients in the group A and in 10 of 34 (29.4%) patients in the group B. In both groups, the major complication incidence was 0 and 3%, respectively.

Conclusion

Although there was the slightly high incidence of complication associated with high rate of co-morbidities in elderly patients, OLIF for degenerative lumbar diseases in elderly patients showed favorable clinical and radiological outcomes.

Full endoscopic lumbar interbody fusion (FELIF): technical note

PURPOSE

Interbody fusion by open discectomy is the usual treatment for degenerative lumbar disease but requires a relatively long recovery period. Prevalent several interbody fusion methods have shown limitations by its own character. Full endoscopic lumbar interbody fusion (FELIF) has advantages in direct decompression of pathology with minimal invasive technique. We report novel technique of endoscopic fusion method through full guided with endoscopic view monitoring system.

METHODS

The authors provide an introduction of FELIF technique followed by a description of the technical steps with discussion on its indications and advantages. In particular, tips to shorten operation time, simplify technical steps, and avoid complications are also presented.

CONCLUSIONS

FELIF is a safe and effective interbody fusion option to decompress the lumbar exiting nerve root and ventral side of dura directly with minimal invasive situation. These slides can be retrieved under Electronic Supplementary Material.

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.

Understanding Retroperitoneal Anatomy for Lateral Approach Spine Surgery

Lateral approach spine surgery provides effective interbody stabilization, and correction and indirect neural decompression with minimal-incision and less invasive surgery compared with conventional open anterior lumbar fusion. It may also avoid the trauma to paraspinal muscles or facet joints found with transforaminal lumbar interbody fusion and posterior lumbar interbody fusion. However, because lateral approach surgery is fundamentally retroperitoneal approach surgery, it carries potential risk to intra- and retroperitoneal structures, as seen in a conventional open anterior approach. There is an innovative lateral approach technique that reveals different anatomical views; however, it requires reconsideration of the traditional surgical anatomy in more detail than a traditional open anterior approach. The retroperitoneum is the compartmentalized space bounded anteriorly by the posterior parietal peritoneum and posteriorly by the transversalis fascia. The retroperitoneum is divided into three compartments by fascial planes: anterior and posterior pararenal spaces and the perirenal space. Lateral approach surgery requires mobilization of the peritoneum and its content and accurate exposure to the posterior pararenal space. The posterior pararenal space is confined anteriorly by the posterior renal fascia, anteromedially by the lateroconal fascia, and posteriorly by the transversalis fascia. The posterior renal fascia, the lateroconal fascia or the peritoneum should be detached from the transversalis fascia and the psoas fascia to allow exposure to the posterior pararenal space. The posterior pararenal space, however, does not allow a clear view and identification of these fasciae as this relationship is variable and the medial extent of the posterior pararenal space varies among patients. Correct anatomical recognition of the retroperitoneum is essential to success in lateral approach surgery. Spine surgeons must be aware that the retroperitoneal membrane and fascia is multilayered and more complex than is commonly understood. Preoperative abdominal images would facilitate more efficient surgical considerations of retroperitoneal membrane and fascia in lateral approach surgery.

A Comparison of Anterior and Posterior Lumbar Interbody Fusions: Complications, Readmissions, Discharge Dispositions, and Costs

STUDY DESIGN

Retrospective database review.

OBJECTIVE

To understand medical complication rates, readmission rates, costs, and discharge dispositions in anterior lumbar interbody fusion (ALIFs) versus transforaminal lumbar interbody fusions (TLIFs)/posterior lumbar interbody fusions (PLIFs) for lumbar degenerative disease.

SUMMARY OF BACKGROUND DATA

Indications for ALIFs versus PLIFs can vary, though benefits of anterior approach surgery include full access to the anterior column and ability to place fusion devices.

METHODS

The PearlDiver Database of Medicare records was utilized for this retrospective database review. A study group consisting solely of ALIF procedure patients was selected for. Similarly, a TLIF/PLIF group was selected for. Both groups were queried for comorbidities, 30 and 90-day complication and readmission rates. Additionally, discharge dispositions, and in-hospital/30-day/90-day Medicare reimbursements were determined.

RESULTS

At both 30 and 90 days postoperatively odds of ileus, wound infection, and lower extremity deep venous thrombosis were significantly increased in the ALIF. However, unadjusted rates and adjusted odds of transfusion or dural tear were significantly decreased in the ALIF patients. Odds of 30-day readmission were 4 times higher in ALIF patients. Additionally, 30 and 90-day total costs of care in ALIF patients were significantly increased by approximately $4800 and $5800 respectively, as compared with patients undergoing TLIF/PLIF.

CONCLUSION

Despite higher initial routine discharge rates, readmissions and costs of postoperative care were significantly increased in ALIF procedures. It is necessary to evaluate etiology of degenerative pathology as ALIFs are successful solutions to anterior translational instability and anterior disc slippage, but may not have the best long-term outcomes and may not be cost-effective compared with a TLIF/PLIF. In light of our data, it is important to assess the risks and benefits of the varying approaches, and the necessity to access the anterior column, when deciding on surgical technique to treat lumbar degenerative pathology.

LEVEL OF EVIDENCE

4.

High-Risk Subgroup Membership Is a Predictor of 30-Day Morbidity Following Anterior Lumbar Fusion

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To determine if membership in a high-risk subgroup is predictive of morbidity and mortality following anterior lumbar fusion (ALF).

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database was utilized to identify patients undergoing ALF between 2010 and 2014. Multivariate analysis was utilized to identify high-risk subgroup membership as an independent predictor of postoperative complications.

RESULTS

Members of the elderly (≥65 years) (OR = 1.3, P = .02) and non-Caucasian (black, Hispanic, other) (OR = 1.7, P < .0001) subgroups were at greater risk for a LOS ≥5 days. Obese patients (≥30 kg/m² ) were at greater risk for an operative time ≥4 hours (OR = 1.3, P = .005), and wound complications (OR = 1.8, P = .024) compared with nonobese patients. Emergent procedures had a significantly increased risk for LOS ≥5 days (OR = 4.9, P = .021), sepsis (OR = 14.8, P = .018), and reoperation (OR = 13.4, P < .0001) compared with nonemergent procedures. Disseminated cancer was an independent risk factor for operative time ≥4 hours (OR = 8.4, P < .0001), LOS ≥5 days (OR = 15.2, P < .0001), pulmonary complications (OR = 7.4, P = .019), and postoperative blood transfusion (OR = 3.1, P = .040).

CONCLUSIONS

High-risk subgroup membership is an independent risk factor for morbidity following ALF. These groups should be targets for aggressive preoperative optimization, and quality improvement initiatives.

Stand-alone anterior lumbar interbody fusion - complications and perioperative results

OBJECTIVES

Historically, anterior lumbar interbody fusion (ALIF) was related to high rates of intraoperative complications and adverse events related to interbody devices. In recent decades, there have been technical adjustments, and cages that are more suitable have emerged. The aim of this study is to evaluate the efficacy and complication rate of the use of stand-alone mini-ALIF using a self-locking cage.

METHODS

Retrospective single center study. Inclusion criteria: retroperitoneal mini-ALIF for single-level fusion (L5S1); self-locking cage; DDD/stenosis and grade I spondylolisthesis. Exclusion criteria: posterior supplementation, previous fusion/arthroplasty. Endpoints: surgery data, intraoperative and perioperative adverse events related both to surgical access and to the intersomatic device.

RESULTS

Eighty-seven cases were enrolled. Median surgical time was 90 min; median blood loss was 100 mL. The median length of stay in the ICU was zero days; median hospital stay was one day. Ten cases had an adverse event (11.5%): four major adverse events (4.6%; 3 L bleeding; DVT; retroperitoneal haematoma; incisional hernia), and seven minor events (8%; peritoneum injury; minor vascular injury; events related to the cage). No cases of retrograde ejaculation were observed. There was improvement in pain, physical restriction, and quality of life (p < 0.001).

CONCLUSIONS

The mini-ALIF procedure performed for single-level fusion at the distal lumbar level demonstrated low adverse event rates related to both the surgical approach and to the intersomatic device, with reduced hospital stay and satisfactory perioperative clinical results.

Effect of Preoperative Anemia on the Outcomes of Anterior Cervical Discectomy and Fusion

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

Preoperative anemia has been associated with an increased need for blood transfusions and postoperative complications. The effects of anemia on the outcomes of anterior cervical discectomy and fusion (ACDF) have not been explored. The present study aimed to evaluate the association between preoperative anemia and 30-day complications following ACDF surgery.

METHODS

Data from the American College of Surgeons National Surgical Quality Improvement Program (2005-2012) was used. Preoperative anemia was defined as hematocrit <39% for males and <36% for females. A bivariate analysis was performed on demographic and perioperative variables. Multivariable logistic regression models were employed, adjusting for patient variables, to identify independent risk factors for complications.

RESULTS

A total of 3500 patients were included of which 444 (12.7%) were anemic patients. Multivariate analysis was used to quantify the predictive power of anemia on key postoperative outcomes, while controlling for the other statistically significant. Preoperative anemia was found to be a statistically significant predictor of any complication (odds ratio [OR] = 1.853; 95% confidence interval [CI] = 1.17-2.934; P = .0086), pulmonary complications (OR = 3.269; 95% CI = 1.745-6.126; P = .0002), intraoperative blood transfusion (OR = 4.364; 95% CI = 1.48-12.866; P = 0.0076), return to operating theatre (OR = 2.655; 95% CI = 1.539-4.582; P = .0005), and length of hospital stay more than 5 days (OR = 2.151; 95% CI = 1.499-3.085; P < .0001).

CONCLUSION

Preoperative anemia appears to be a significant predictor of perioperative complications, reoperation, and extended length of hospital stay in patients undergoing elective ACDF. Future studies should explore outcomes of treatment of preoperative anemia prior to surgery to determine the optimal management strategy.

Outcomes of open staged corrective surgery in the setting of adult spinal deformity

BACKGROUND CONTEXT

Adult spinal deformity (ASD) represents a constellation of complex malalignments affecting the spinal column. Corrective surgical procedures aimed at improving ASD can be equally challenging, and commonly require multiple index procedures and potential revisions before definitive management. There is a paucity of data comparing the outcomes of same-day(simultaneous [SIM]) and 2-day (staged [STA]) procedures for long spinal fusions for ASD. Using a large patient cohort with surgeon- and patient-reported outcomes will be particularly useful in determining the utility and effect of staging long spinal fusions for ASD.

PURPOSE

This study aimed to compare intraoperative, perioperative, and 2-year outcomes of STA and SIM procedures correcting ASD.

STUDY DESIGN

This is a retrospective analysis of a prospective multicenter database.

PATIENT SAMPLE

A total of 142 patients (71 STA, 71 SIM) were included.

OUTCOME MEASURES

Primary outcome measures were intra- and perioperative (6 weeks) complication rates. Secondary outcome measures were 2-year thoracolumbar and spinopelvic radiographic parameters, 2-year health-related quality of life (HRQoL) changes (Oswestry Disability Index [ODI] and Short Form-36 [SF-36]), and 2-year complication rates.

METHODS

Inclusion criteria included patients with ASD ≥18 years with 6-week and 2-year follow-up. Propensity score matching identified similar patients undergoing STA or SIM long spinal fusions based on surgical invasiveness, pelvic tilt, and sagittal vertical axis (SVA). Complications, HRQoL scores (Scoliosis Research Society-22 Patient Questionnaire [SRS-22r], SF-36, ODI), and patient characteristics were compared across and within treatment groups at follow-up with analysis of variance (ANOVA) and paired t tests at three surgical stages: intraoperatively, perioperatively (6 weeks), and postoperatively (>6 weeks).

RESULTS

A total of 142 patients were included (71 STA, 71 SIM). Matching STA and SIM groups based on degree of deformity and surgical invasiveness created two groups similar in overall correction of the surgery. Patients undergoing STA underwent more anterior lumbar interbody fusion (ALIF) and lateral lumbar interbody fusion (LLIF) procedures, whereas patients undergoing SIM had longer fusions. Charlson comorbidity index and revision status were similar between groups (p>.05). Staging procedures had significantly more complications causing reoperation (STA: 47% vs. SIM: 8%, p=.021), and had a greater number of perioperative complications requiring a return to the operating room (OR) (STA: 9.9% vs. SIM: 1.4%, p=.029). There was no difference in intraoperative complications, mortality, or perioperative infection or wound complications (p>.05) between the two procedures. At 2-year follow-up, incidence of revision surgery was higher in STA (STA: 21.1% vs. SIM: 8.5%, p=.033).

CONCLUSION

Staged spinal fusions, which add ALIFs and LLIFs to the procedure, compared with similar-correction SIM procedures, result in similar intraoperative complication incidence, but significantly higher rates of peri- and postoperative complications leading to revision. Functional outcomes, radiographic parameters, and mortality were similar. This will aid surgeons in their determination of the optimal treatment for such complex procedures.

Preoperative evaluation of left common iliac vein in oblique lateral interbody fusion at L5-S1

PURPOSE

Oblique lateral interbody fusion (OLIF) L5-S1 is essentially to perform an anterior lumbar interbody fusion (ALIF) in the lateral position. Because the surgical procedures are performed "obliquely" over the left common iliac vein (LCIV), ensuring that the vein is protected which is particularly important. We aimed to evaluate the configuration of LCIV and its risk of mobilization during anterior approach at L5-S1 segment.

METHODS

This study involved 65 consecutive patients who underwent anterior lumbar fusion (ALIF, n = 39; OLIF, n = 26) at the L5-S1 segment. Three independent examiners evaluated the configuration of the LCIV at the L5-S1 disc on axial magnetic resonance images of the lumbar spine. The LCIV was categorized into three types according to the difficulty of mobilization: type I (no requirement for mobilization; LCIV runs laterally for more than two-thirds of the length of the left side of the L5-S1 disc), type II (easy mobilization; LCIV obstructs the L5-S1 disc space, but the perivascular adipose tissue is present under the LCIV), and type III (potentially difficult mobilization; no perivascular adipose tissue under the LCIV). The patient records were reviewed for vascular complications.

RESULTS

There were 21 men and 44 women in this study, with a mean age of 63.4 years (range 19-83 years). Type I LCIV configuration was found in 32 (49.2%) patients, type II in 18 (27.7%), and type III in 15 (23.1%). There were 7 (10.8%) patients with LCIV injury (type I, n = 0; type II, n = 2; type III, n = 5) (P = 0.003). Intraobserver reliability for the LCIV classification ranged from substantial to excellent, and interobserver reliability ranged from moderate to excellent.

CONCLUSIONS

Preoperative evaluation for anterior approach to the L5-S1 segment should take account of the LCIV position, as well as the difficulty of its mobilization. The type III LCIV configuration showed a high rate of vascular injury.

L5 corpectomy-the lumbosacral segmental geometry and clinical outcome-a consecutive series of 14 patients and review of the literature

PURPOSE

We analyzed the lumbosacral segmental geometry and clinical outcome in patients undergoing L5 corpectomy.

METHODS

Fourteen consecutive patients who underwent L5 (n = 12) or L4 + 5 (n = 2) corpectomy at our department between January 2010 and April 2015 were included. All patients underwent a baseline physical and neurologic examination on admission. The diagnostic routine included MRI and CT scans and, if possible, an upright X-ray of the lumbar spine before and after surgery. The local lordosis angle [L4(L3)-S1] was measured.

RESULTS

The most common pathology was infection (N = 7), followed by neoplastic disease (n = 3), pseudarthrosis (n = 2) after previous spinal fusion procedures and burst fractures (n = 2) of the L5 vertebral body. We observed seven complications (2 intraoperative; 5 postoperative) in five (36%) patients. Three patients needed revision surgery because of cage subsidence and/or dislodgement (21%). Additional anterior plating was used in two of the revision surgeries to secure the cage. Two spondylodiscitis patients (14%) with complications died of sepsis. Of the 12 remaining patients, 8 were available for follow-up.

CONCLUSION

L5 corpectomy is a technically challenging but feasible procedure even though the overall complication rate can be as high as 36%. The radiologic and clinical outcome seems to be better in patients with a small lordosis angle between L4(L3) and S1, since an angle of >50 degrees seems to facilitate cage dislodgement. Anterior plating should be considered in these cases to prevent implant failure.

Subsidence following anterior lumbar interbody fusion (ALIF): a prospective study

BACKGROUND

Anterior lumbar interbody fusion (ALIF) is a widely used surgical technique for disorders of the lumbar spine. One potential complication is the subsidence of disc height in the post-operative period. Few studies have reported the rate of subsidence in ALIF surgery prospectively. We prospectively evaluated the rate of subsidence in adult patients undergoing ALIF.

METHODS

Results were obtained by reviewing scans of 147 patients. Disc heights were measured on radiographic scans taken pre-operatively in addition to post-operatively immediately, at 6 weeks and at 18 months. The anterior and posterior intervertebral disc heights were measured. Subsidence was defined as greater than or equal to 2 mm loss of height.

RESULTS

A total of 15 patients (10.2%) had subsidence, with 7 being male. Each case was of delayed cage subsidence (DCS) >6 weeks postoperatively. The mean subsidence was 4.7 mm (range, 2.4-7.8). Mean anterior disc height was 8.6±0.4 mm preoperatively, which improved to 15.1±0.5 mm at latest follow-up. Mean posterior disc height was 4.7±0.2 mm preoperatively, which improved to 8.7±0.4 mm at latest follow-up. The mean lumbar lordosis (LL) angle was 42.5°±10.8° and the mean local disc angle (LDA) was 6.7°±4.0°. The 91.2% (n=114/125) of patients with appropriate radiological follow-up demonstrated fusion by latest follow-up. There was no correlation between subsidence rate with patient reported outcomes [Visual Analog Scale (VAS), Oswestry Disability Index (ODI) and Short Form 12 Item survey (SF-12)] and fusion rates. There was a significant negative correlation between LL and extent of subsidence (Pearson correlation =-0.754, P=0.012).

CONCLUSIONS

In conclusion, we found that the subsidence rate at follow-up was generally low following standalone ALIF for this patient series. Patient clinical outcomes and bony fusion rates were not significantly influenced by subsidence.

Anterior Lumbar Interbody Fusion With and Without an "Access Surgeon": A Systematic Review and Meta-analysis

STUDY DESIGN

A systematic review and meta-analysis.

OBJECTIVE

The aim of this study was to investigate the outcomes of anterior lumber interbody fusion (ALIF) with and without an "access surgeon."

SUMMARY OF BACKGROUND DATA

Anterior approaches for spine operations have become increasingly popular but may often involve unfamiliar anatomy and territory for spine surgeons, potentially placing the patient at risk to a greater proportion of approach-related complications. Thus, many spine surgeons require or prefer the assistance of an "access surgeon" to perform the exposure. However, there has been much debate about the necessity of an "access surgeon."

METHODS

A systematic search of six databases from inception to April 2016 was performed by two independent reviewers. Meta-analysis was used to pool overall rates, and compare the outcomes of ALIF with an access surgeon and without.

RESULTS

A total of 58 (8028 patients) studies were included in this meta-analysis. The overall intraoperative complications were similar with and without an "access surgeon." The overall pooled rate of arterial injuries [no access 0.44% vs. access 1.16%, odds ratio (OR) 2.67, P < 0.001], retrograde ejaculation (0.41% vs. 0.96%, OR 2.34, P = 0.005), and ileus (1.93% vs. 2.26%, OR 2.45, P < 0.001) was higher with an "access surgeon." However, the overall pooled rates of peritoneal injury (0.44% vs. 0.16%, OR 0.36, P = 0.034) and neurological injury (0.99% vs. 0.11%, OR 0.11, P < 0.001) were lower with an "access surgeon." Total postoperative complications (5.95% vs. 4.08%, OR 0.67, P < 0.001) were lower with an "access surgeon" along with prosthesis complications (1.59% vs. 0.89%, OR 0.56, P < 0.001) and reoperation rates (2.28% vs. 1.31%, OR 0.57, P < 0.001).

CONCLUSION

Compared with no access surgeon, the use of an access surgeon was associated with similar intraoperative complication rates, higher arterial injuries, retrograde ejaculation, ileus, and lower prosthesis complications, reoperation rates, and postoperative complications. In cases wherein exposure may be difficult, support from an "access surgeon" should be available.

LEVEL OF EVIDENCE

1.

Biomechanical comparison of multilevel lateral interbody fusion with and without supplementary instrumentation: a three-dimensional finite element study

Background

Lateral lumbar interbody fusion (LLIF) is a popular, minimally invasive technique that is used to address challenging multilevel degenerative spinal diseases. It remains controversial whether supplemental instrumentation should be added for multilevel LLIF. In this study, we compared the kinematic stability afforded by stand-alone lateral cages with those supplemented by bilateral pedicle screws and rods (PSR), unilateral PSR, or lateral plate (LP) fixation using a finite-element (FE) model of a multi-level LLIF construct with simulated osteoporosis. Additionally, to evaluate the prospect of cage subsidence, the stress change characteristics were surveyed at cage-endplate interfaces.

Methods

A nonlinear 3-dimensional FE model of the lumbar spine (L2 to sacrum) was used. After validation, four patterns of instrumented 3-level LLIF (L2-L5) were constructed for this analysis: (a) 3 stand-alone lateral cages (SLC), (b) 3 lateral cages with lateral plate and two screws (parallel to endplate) fixated separately (LPC), (c) 3 lateral cages with bilateral pedicle screw and rod fixation (LC + BPSR), and (d) 3 lateral cages with unilateral pedicle and rod fixation (LC + UPSR). The segmental and overall range of motion (ROM) of each implanted condition were investigated and compared with the intact model. The peak von Mises stresses upon each (superior) endplate and the stress distribution were used for analysis.

Results

BPSR provided the maximum reduction of ROM among the configurations at every plane of motion (66.7–90.9% of intact spine). UPSR also provided significant segmental ROM reduction (45.0–88.3%). SLC provided a minimal restriction of ROM (10.0–75.1%), and LPC was found to be less stable than both posterior fixation (23.9–86.2%) constructs. The construct with stand-alone lateral cages generated greater endplate stresses than did any of the other multilevel LLIF models. For the L3, L4 and L5 endplates, peak endplate stresses caused by the SLC construct exceeded the BPSR group by 52.7, 63.8, and 54.2% in flexion, 22.3, 40.1, and 31.4% in extension, 170.2, 175.1, and 134.0% in lateral bending, and 90.7, 45.5, and 30.0% in axial rotation, respectively. The stresses tended to be more concentrated at the periphery of the endplates.

Conclusions

SLC and LPC provided inadequate ROM restriction for the multilevel LLIF constructs, whereas lateral cages with BPSR or UPSR fixation provided favorable biomechanical stability. Moreover, SLC generated significantly higher endplate stress compared with supplemental instrumentation, which may have increased the risk of cage subsidence. Further biomechanical and clinical studies are required to validate our FEA findings.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-017-1387-6) contains supplementary material, which is available to authorized users.

The Oblique Anterolateral Approach to the Lumbar Spine Provides Access to the Lumbar Spine With Few Early Complications

BACKGROUND

During the last 20 years several less-invasive anterior approaches to the lumbar spine have become standard, including the extreme lateral transpsoas approach. Although it is associated with a lower risk of vascular injury compared with anterior midline approaches, neuromonitoring is considered mandatory to avoid neurologic complications. Interestingly, despite neuromonitoring, the reported risk of neurologic deficits with the extreme lateral transpsoas approach is greater than observed with other anterior approaches. An alternative lateral, oblique, psoas-sparing approach, recently named the oblique lumbar interbody fusion, uses the anatomic pathway between the abdominal vessels anteriorly and the lumbar plexus laterally to decrease the risk of neurologic and vascular injury; however, as yet, little on this new approach has been reported.

QUESTIONS/PURPOSES

We asked: what proportion of patients experienced (1) perioperative complications (overall complications), (2) vascular complications, and (3) neurologic complications after less-invasive anterior lumbar interbody fusion through the oblique lumbar interbody approach at one high-volume center?

METHODS

We performed a chart review of intra- and perioperative complications of all patients who had undergone minimally invasive anterior lumbar interbody fusion through a lateral psoas-sparing approach from L1 to L5 during a 12-year period (1998-2010). During the study period, the oblique, psoas-sparing approach was the preferred approach of the participating surgeons in this study, and it was performed in 812 patients, all of whom are studied here, and all of whom have complete data for assessment of the short-term (inpatient-only) complications that we studied. In general, we performed this approach whenever possible, although it generally was avoided when a patient previously had undergone an open retro- or transperitoneal abdominal procedure, or previous implantation of hernia mesh in the abdomen. During the study period, posterior fusion techniques were used in an additional 573 patients instead of the oblique lumbar interbody fusion when we needed to decompress the spinal canal beyond what is possible through the anterior approach. In case of spinal stenosis calling for fusion in combination with a high disc space, severe endplate irregularity, or severe biomechanical instability, we combined posterior decompression with oblique lumbar interbody fusion in 367 patients. Complications were evaluated by an independent observer who was not involved in the decision-making process, the operative procedure, nor the postoperative care by reviewing the inpatient records and operative notes.

RESULTS

A total of 3.7% (30/812) of patients who underwent the oblique lumbar interbody fusion experienced a complication intraoperatively or during the hospital stay. During the early postoperative period there were two superficial (0.24%) and three deep (0.37%) wound infections and five superficial (0.62%) and six deep (0.86%) hematomas. There were no abdominal injuries or urologic injuries. The percentage of vascular complications was 0.37% (n = 3). The percentage of neurologic complications was 0.37% (n = 3).

CONCLUSIONS

The risk of vascular complications after oblique lumbar interbody fusion seems to be lower compared with reported risk for anterior midline approaches, and the risk of neurologic complications after oblique lumbar interbody fusion seems to be lower than what has been reported with the extreme lateral transpsoas approach; however, we caution readers that head-to-head studies will need to be performed to confirm our very preliminary comparisons and results with the oblique psoas-sparing approach. Similarly, future studies will need to evaluate this approach in terms of later-presenting complications, such as infection and pseudarthrosis formation, which could not be assessed using this inpatient-only approach. Nevertheless, with the results of this study the oblique psoas-sparing approach can be described as a less-invasive alternative for anterior lumbar fusion surgery from L1 to L5 with a low risk of vascular and neurologic damage and without costly intraoperative neuromonitoring tools.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Influence of Obesity on Access-Related Complications During Anterior Lumbar Spine Interbody Fusion

OBJECTIVE

The anterior lumbar spine approach has gained in popularity in recent years, but the associated access-related complications for obese patients have not been clearly established. This study aimed to analyze the relationship between obesity or overweight and the safety of the anterior lumbar spine approach.

METHODS

Eighty-four consecutive patients admitted for lumbar spine surgery by anterior approach between 2011 and 2014 were included. The surgical approach consisted of left lateral minilaparotomy and retroperitoneal dissection. The patients were categorized into 3 different groups according to their body mass index (BMI). The studied outcomes measures included medical history, BMI, the number of fused levels, surgery duration, blood loss, vascular injury, day of discharge, surgical revision, and wound infection.

RESULTS

No significant difference was found across the BMI groups with regard to vascular or infectious complications. The duration of surgery was significantly higher in the obese group.

CONCLUSIONS

Because BMI does not seem to increase the overall risk of complications, the anterior lumbar spine approach should be considered in obese or overweight patients, as in nonoverweight patients.

Effect of Anatomic Variability and Level of Approach on Perioperative Vascular Complications With Anterior Lumbar Interbody Fusion

STUDY DESIGN

Retrospective review of prospectively collected data.

OBJECTIVE

The study aim was to determine the prevalence of vascular complications associated with anterior lumbar interbody fusion (ALIF) as a function of anatomic variation and the number of levels fused.

SUMMARY OF BACKGROUND DATA

ALIF often requires mobilization of the great vessels, particularly when exposing levels above L5-S1. The exposure can be more challenging in the setting of spondylolisthesis or transitional anatomy.

METHODS

This retrospective review of prospectively collected data from our spine database identified 204 patients who had undergone single level (n = 142) or multilevel (n = 62) ALIF from 2008 to 2013 with minimum 6-month follow-up. Average age was 58 years; 57% were female. Preoperative radiographic assessment for spondylolisthesis and transitional anatomy was performed. Body mass index, estimated blood loss, and levels of ALIF were recorded. Intraoperative vascular injury, postoperative deep venous thrombosis, and pulmonary embolism events were noted.

RESULTS

Eleven patients experienced postoperative thromboembolic events and were more likely to have had intraoperative vascular injury compared with patients who did not develop a vascular complication (36% and 5%, respectively; P = 0.004). Estimated blood loss was significantly higher in patients with spondylolisthesis when compared to patients without spondylolisthesis (520 cc vs. 103 cc, respectively; P = 0.017) or transitional anatomy (347 cc vs. 262 cc, respectively; P = 0.022). Patients undergoing multilevel ALIF had significantly higher blood loss than patients undergoing a single level procedure (684 cc vs. 107 cc; P < 0.001). Patient characteristics, blood loss, anatomic variation, and level of approach were not associated with the development of postoperative thromboembolic complications.

CONCLUSION

Performing ALIF in the setting of spondylolisthesis or transitional anatomy resulted in higher blood loss. Patients undergoing multilevel rather than single level ALIF experienced greater blood loss. Because patients with intraoperative vascular injury had increased likelihood of postoperative thromboembolic event, thrombosis prophylaxis should be considered in these patients.

LEVEL OF EVIDENCE

4.

Anterior lumbar spine surgery: a systematic review and meta-analysis of associated complications

BACKGROUND CONTEXT

The anterior approach to the lumbar spine is increasingly used to accomplish various surgical procedures. However, the incidence and risk factors for complications associated with anterior lumbar spine surgery (ALS) have not been fully elucidated.

PURPOSE

To identify and document types of complications and complication rates associated with ALS, determine risk factors for these events, and evaluate the effect of measures used to decrease complication rates.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

A systematic review of the English-language literature was conducted for articles published between January 1992 and December 2013. A MEDLINE search was conducted to identify articles reporting complications associated with ALS. For each complication, the data were combined using a generalized linear mixed model with a binomial probability distribution and a random effect based on the study. Predictors used were the type of procedure (open, minimally invasive, or laparoscopic), the approach used (transperitoneal vs. retroperitoneal), use of recombinant bone morphogenetic protein-2, use of preoperative computed tomography angiography (CTA), and the utilization of an access surgeon. Open surgery was used as a reference category.

RESULTS

Seventy-six articles met final inclusion criteria and reported complication rates in 11,410 patients who underwent arthrodesis and/or arthroplasty via laparoscopic, mini-open, and open techniques. The overall complication rate was 14.1%, with intraoperative and postoperative complication rates of 9.1% and 5.2%, respectively. Only 3% of patients required reoperation or revision procedures. The most common complications reported were venous injury (3.2%), retrograde ejaculation (2.7%), neurologic injury (2%), prosthesis related (2%), postoperative ileus (1.4%), superficial infection (1%), and others (1.3%). Laparoscopic and transperitoneal procedures were associated with higher complication rates, whereas lower complication rates were observed in patients receiving mini-open techniques. Our analysis indicated that the use of recombinant bone morphogenetic protein-2 was associated with increased rates of retrograde ejaculation; however, there may be limitations in interpreting these data. Data regarding the use of preoperative CTA and an access surgeon were limited and demonstrated mixed benefit.

CONCLUSIONS

Overall complication rates with ALS are relatively low, with the most common complications occurring at a rate of 1% to 3%. Complication rates are related to surgical technique, approach, and implant characteristics. Further randomized controlled trials are needed to validate the use of preventative measures including CTA and the use of an access surgeon.

Surgical treatments for degenerative lumbar scoliosis: a meta analysis

PURPOSE

Degenerative lumbar scoliosis (DLS) is a spinal deformity that typically develops in adults over 50 years old. Although its etiology is unclear, asymmetric degeneration of the spine is the main cause. Individuals with DLS may experience no symptoms of the deformity, mild symptoms, or severe disability. Most patients with DLS receive conservative treatment, while a small number of patients receive surgery for severe DLS with back pain and/or progressive neurological symptoms. A variety of surgical procedures have emerged. However, a systemic comparison of these surgical procedures is currently unavailable. This study reviews the main outcomes and complications of surgical treatments.

METHODS

A meta analysis of main outcomes and complications of surgical treatments of DLS was conducted through searching PubMed and EMbase databases.

RESULTS

A total of 45 studies were included in this study, which were classified into four surgical categories. Nine studies utilized isolated decompression, 12 used short interbody fusion, 17 used long interbody fusion, and 11 studies included patients using short or long interbody fusion or surgery other than fusion, respectively. Decompression surgery is used to release the symptoms of neurogenic claudication. Spine fusion is widely utilized to prevent worsening of the curve. Instrumentation has been used together with fusion to straighten the spine, correct sagittal imbalance, and repair rotational defects. Decompression is commonly combined with fusion surgery when treating an individual with DLS.

CONCLUSION

Despite a high rate of complications, this review demonstrates that surgery is an effective and reasonable treatment intervention for severe DLS and ultimately improves spine function and deformity. This review also suggests that large scale, high quality studies with long term follow-up are needed to provide more reliable evidence for future evaluation.

Prospective evaluation of 1-year outcomes in single-level percutaneous lumbar transfacet screw fixation in the lateral decubitus position following lateral transpsoas interbody fusion

PURPOSE

Lateral transpsoas lumbar interbody fusion (LTIF) is an accepted treatment for degenerative lumbar disc disease. Bilateral percutaneous transfacet (TF) fixation is a promising option for stabilization following LTIF. Here, we describe our experience with this technique and assess the clinical outcomes and efficacy.

METHODS

Thirty-eight consecutive patients were identified who underwent LTIF followed by bilateral percutaneous transfacet fixation in the lateral position. Preoperative and 1-year postoperative VAS scores, and operative data were prospectively recorded. One-year outcomes were also assessed according to the MacNab criteria. Fusion was assessed at 1 year via computed tomography and dynamic radiography. Two-tailed Student's t test was used to compare VAS scores.

RESULTS

Twenty-six patients underwent fusion at L4-5, 11 at L3-4, and one at L2-3; two patients were lost to follow-up. Mean operative time was 148.0 ± 47.9 min; mean blood loss was 33.0 ± 26.1 ml; mean hospital stay was 53.5 ± 51.2 h. Mean preoperative VAS scores for back and leg pain were 7.4 ± 3.0 and 7.0 ± 2.9, respectively; mean postoperative VAS scores for back and leg pain were 1.9 ± 2.4 (p < 0.0001) and 2.0 ± 3.0 (p < 0.0001), respectively. Most (89 %) patients had some relief, 72 % good to excellent and 17 % fair outcomes; eleven percent had little to no relief. There was one postoperative complication (pulmonary embolus). All patients had evidence of solid bony fusion.

CONCLUSIONS

Percutaneous transfacet fixation in the lateral position is a safe and effective alternative for fixation after LTIF and may be associated with shorter operative time and less blood loss than other posterior fixation techniques.

Successful treatment of severe sympathetically maintained pain following anterior spine surgery

Sympathetic dysfunction is one of the possible complications of anterior spine surgery; however, it has been underestimated as a cause of complications. We report two successful experiences of treating severe dysesthetic pain occurring after anterior spine surgery, by performing a sympathetic block. The first patient experienced a burning and stabbing pain in the contralateral upper extremity of approach side used in anterior cervical discectomy and fusion, and underwent a stellate ganglion block with a significant relief of his pain. The second patient complained of a cold sensation and severe unexpected pain in the lower extremity of the contralateral side after anterior lumbar interbody fusion and was treated with lumbar sympathetic block. We aimed to describe sympathetically maintained pain as one of the important causes of early postoperative pain and the treatment option chosen for these cases in detail.

Anterior lumbar interbody fusion using recombinant human bone morphogenetic protein-2: a prospective study of complications

OBJECT

The use of recombinant human bone morphogenetic protein-2 (rhBMP-2) in anterior lumbar interbody fusion (ALIF) is controversial regarding the reported complication rates and cost. The authors aimed to assess the complication rates of performing ALIF using rhBMP-2.

METHODS

This is a prospective study of consecutive patients who underwent ALIF performed by a single spine surgeon and a single vascular surgeon between 2009 and 2012. All patients underwent placement of a polyetheretherketone (PEEK) cage filled with rhBMP-2 and a separate anterior titanium plate. Preoperative clinical data, operative details, postoperative complications, and clinical and radiographic outcomes were recorded for all patients. Clinical outcome measures included back and leg pain visual analog scale scores, Oswestry Disability Index (ODI), and SF-36 Physical and Mental Component Summary (PCS and MCS) scores. Radiographic assessment of fusion was performed using high-definition CT scanning. Male patients were screened pre- and postoperatively regarding sexual dysfunction, specifically retrograde ejaculation (RE).

RESULTS

The study comprised 131 patients with a mean age of 45.3 years. There were 67 men (51.1%) and 64 women (48.9%). Of the 131 patients, 117 (89.3%) underwent ALIF at L5-S1, 9 (6.9%) at L4-5, and 5 (3.8%) at both L4-5 and L5-S1. The overall complication rate was 19.1% (25 of 131), with 17 patients (13.0%) experiencing minor complications and 8 (6.1%) experiencing major complications. The mean estimated blood loss per ALIF level was 115 ml. There was 1 incidence (1.5%) of RE. No significant vascular injuries occurred. No prosthesis failure occurred with the PEEK cage and separate anterior screw-plate. Back and leg pain improved 57.2% and 61.8%, respectively. The ODI improved 54.3%, with PCS and MCS scores improving 41.7% and 21.3%, respectively. Solid interbody fusion was observed in 96.9% of patients at 12 months.

CONCLUSIONS

Anterior lumbar interbody fusion with a vascular access surgeon and spine surgeon, using a separate cage and anterior screw-plate, provides a very robust and reliable construct with low complication rates, high fusion rates, and positive clinical outcomes, and it is cost-effective. The authors did not experience the high rates of RE reported by other authors using rhBMP-2.

Prior abdominal surgery is associated with an increased risk of postoperative complications after anterior lumbar interbody fusion

STUDY DESIGN

Retrospective medical record review.

OBJECTIVE

The purpose of this study was to determine whether a history of abdominal/pelvic surgery confers an increased risk of retroperitoneal anterior approach-related complications when undergoing anterior lumbar interbody fusion.

SUMMARY OF BACKGROUND DATA

As anterior lumbar interbody fusion gains popularity, both anterior retroperitoneal approach have become increasingly used.

METHODS

The records of 263 patients, who underwent infraumbilical retroperitoneal approach to the anterior aspect of the lower lumbar spine for a degenerative spine condition between 2007 and 2011 were retrospectively reviewed. Patient's demographics, risk factors, preoperative diagnosis, surgical history, level of the anterior fusion, and perioperative complications were collected. Anterior retroperitoneal approach to the spine was carried out by a single general surgeon.

RESULTS

Ninety-seven patients (37%) developed at least 1 complication. Forty-nine percent of patients with a history of abdominal surgery developed a postoperative complication compared with 28% of patients without such history (RR = 1.747, P≤ 0.001). After controlling for other factors such as age, sex, body mass index, diagnostic groups, and preoperative comorbidities (hypertension, diabetes, and smoking status), these differences remained statistically significant. When each type of complication was considered separately, there was a statistically significant difference in the incidence of general complications (RR = 2.384, P = 0.007), instrumentation-related complications (RR = 2.954, P = 0.010), and complications related to the anterior approach (RR = 1.797, P = 0.021).

CONCLUSION

Anterior lumbar interbody fusion via a midline incision and a retroperitoneal approach was associated with 37% overall rate of complication. Patients with a history of abdominal or pelvic surgery are at a higher risk of developing general, instrumentation, and anterior approach-related complications.

Access-related complications in anterior lumbar surgery in patients over 60 years of age

PURPOSE

The anterior approach is widely used for access to the lumbar spine in the setting of adult deformity either as a stand-alone procedure or in combined anterior-posterior procedures. Access-related complication rates have so far not been reported in an elderly patient population, in which it has been suggested that anterior lumbar surgery is indicated with caution. Here, the complication rates in patients over 60 years of age are reported.

METHODS

A retrospective chart review in a consecutive series of 31 patients over 60 years of age and in which a retroperitoneal access to the lumbar spine was performed. All charts including anaesthetic charts were reviewed and the patients' demographics, exact surgical procedure, comorbidities, and potential risk factors, as well as intraoperative and vascular complications noted. Patients who had revision anterior surgery, anterior surgery for tumour resection, trauma or infection were excluded.

RESULTS

The average age of patients was 64.9 years, ranging 60-81. Eighteen patients were female and 13 male. The average body mass index was 26.7 ranging 18.5-44.0. The indications for surgery were degenerative scoliosis (12 patients), degenerative spondylosis (7 patients), degenerative spondylolisthesis (5 patients), iatrogenic spondylolisthesis following prior posterior decompression (5 patients), and pseudarthrosis following posterolateral instrumented fusion (2 patients). In 10 patients, a single-level anterior lumbar interbody fusion (ALIF) was carried out (1 L3/4, 5 L4/5, 4 L5/S1) and in 11 patients ALIF was performed on two levels (1 L2-4, 1 L3-5, 9 L4-S1). In three patients, 3 levels from L3 to S1 were approached and in seven patients 4 levels from L2 to S1. Patients with three- and four-level anterior lumbar surgery had higher blood loss than two- and one-level surgery (616 ± 340 vs 439 ± 238, p = 0.036). The overall complication rate was 29% (9/31), which included four vascular injuries and one pulmonary embolism. The vascular complication rate was 13% (4/31) with two arterial and two venous injuries requiring repair. No major blood loss over 2,000 ml occurred.

CONCLUSIONS

Anterior lumbar surgery in an elderly population does not necessarily have higher overall complication rates than in a younger population. The risk of vascular injury requiring repair was higher, but has not resulted in major blood loss and the procedure therefore can be carried out safely. The overall complication rate and blood loss compare favourably to complication rates in posterior adult deformity procedures.