Comparative Radiographic Outcomes of Lateral and Posterior Lumbar Interbody Fusion in the Treatment of Degenerative Lumbar Kyphosis

Sagittal Alignment in the Degenerative Lumbar Spine: Surgical Planning

➤ Sagittal alignment of the spine has gained attention in the field of spinal deformity surgery for decades. However, emerging data support the importance of restoring segmental lumbar lordosis and lumbar spinal shape according to the pelvic morphology when surgically addressing degenerative lumbar pathologies such as degenerative disc disease and spondylolisthesis.➤ The distribution of caudal lordosis (L4-S1) and cranial lordosis (L1-L4) as a percentage of global lordosis varies by pelvic incidence (PI), with cephalad lordosis increasing its contribution to total lordosis as PI increases.➤ Spinal fusion may lead to iatrogenic deformity if performed without attention to lordosis magnitude and location in the lumbar spine.➤ A solid foundation of knowledge with regard to optimal spinal sagittal alignment is beneficial when performing lumbar spinal surgery, and thoughtful planning and execution of lumbar fusions with a focus on alignment may improve patient outcomes.

A Comparison of Hidden Blood Loss Between Multilevel Posterior Lumbar Interbody Fusion and Lateral Lumbar Interbody Fusion in Adult Spinal Deformity Patients

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

This study aimed to compare transfusion and blood loss volumes, particularly hidden blood loss volume, in adult spinal deformity patients undergoing lateral lumbar interbody fusion (LLIF) and posterior lumbar interbody fusion (PLIF). Corrective surgery for adults with spinal deformity patients can be performed via the traditional posterior approach (PLIF) or minimally invasive lateral approach (LLIF). LLIF is associated with longer or comparable operation times and lower intraoperative blood loss. However, hidden blood loss has not been compared between the two procedures.

METHODS

We compared hidden blood loss and other blood loss volumes, transfusion volume, operation time, and radiographic surgical outcomes between LLIF patients (n = 71) and PLIF patients (n = 33) who underwent surgery in our institution from September 2011 to June 2018. All patients provided informed consent in accordance with the Declaration of Helsinki. Institutional ethics committee conducted this study approval was obtained.

RESULTS

Transfusion volume and intraoperative and total blood loss volumes were significantly higher in the PLIF group. Operation time and HBL did not significantly differ. The hidden blood loss-to-intraoperative blood loss ratio was significantly higher in the LLIF group (113% vs 60%; P = .004). Radiographic measures of outcome were significantly better after surgery than before in both groups.

CONCLUSIONS

Although intraoperative blood loss was less with LLIF than PLIF, HBL was similar between the approaches. Patients undergoing LLIF should be followed closely for postoperative anemia even if intraoperative blood loss is low.

Prone Transpsoas Lateral Interbody Fusion (PTP LIF) with Anterior Docking: Preliminary functional and radiographic outcomes

Background

Disadvantages of lateral interbody fusion (LIF) through a direct, transpsoas approach include difficulties associated with lateral decubitus positioning and limited sagittal correction without anterior longitudinal ligament release or posterior osteotomy. Prior technical descriptions advocate anchoring or docking the retractor into the posterior to middle aspect of the disc space.

Methods

72 patients who underwent 116 total levels of Prone Transpsoas (PTP) LIF with anterior docking with a single surgeon between December 2021 and May 2023 were included. Patient characteristics, perioperative data, as well as postoperative functional and radiographic outcomes were recorded. Subgroup analysis was performed for patients who underwent single-level PTP LIF with single-level percutaneous fixation (SLP). Patients in the SLP subgroup did not undergo direct decompression, release, or osteotomy.

Results

N=41 (56.9%) of cases included the L4-5 level. No vascular, bowel, or other visceral complications occurred. No patients developed a permanent motor deficit. Both the total cohort and the SLP group demonstrated statistically significant improvements in functional outcomes including Oswestry Disability Index (ODI) and Visual Analog Scale (VAS) as well as all radiographic parameters measured. Mean total operative time (incision to completion of closure for lateral and posterior fusion) in the SLP group was 104.3 minutes with a significant downward trend with increasing surgeon experience. The SLP group demonstrated a 9.9° increase in segmental lordosis (SL), a 7.5° increase in lumbar lordosis (LL), 5.3° reduction in pelvic tilt (PT), and a decrease in pelvic incidence - lumbar lordosis mismatch (PI-LL) from 11.0° preoperatively to 3.9°, postoperatively (p<.01).

Conclusions

PTP LIF with anterior docking may address shortcomings associated with traditional lateral interbody fusion by producing safe and reproducible access with improved restoration of segmental lordosis and optimization of spinopelvic parameters.

Prone position lateral interbody fusion-a narrative review

Background and Objective

Lateral access lumbar interbody fusion is an increasingly popular procedure that allows for anterior column support through discectomy, endplate preparation, and interbody insertion. This procedure was initially described and performed with the patient in the lateral decubitus position. This would typically be followed by repositioning the patient to the prone position for pedicle screw fixation. Increasingly common is the lateral access lumbar interbody fusion in the prone position. This narrative review seeks to summarize the available literature on advantages, disadvantages, and unique features of the prone position lateral access lumbar interbody fusion.

Methods

We performed a narrative review of articles published up to 01 November 2022 through a PubMed search. The search terms "prone lateral spine surgery" and "lateral approach spine surgery" AND "prone position" were used. Articles not available in English were excluded. The search result abstracts were independently reviewed by 2 authors and 28 full text articles were reviewed. Both reviewing authors were orthopedic surgery chief residents.

Key Content and Findings

There are several unique advantages as well as disadvantages to the prone position lateral interbody fusion. Some advantages include ease of placing pedicle screws, simultaneous posterior and lateral access, greater ease in achieving segmental lumbar lordosis, and a relatively safer positioning of the psoas muscle, lumbar plexus, and abdominal structures. Disadvantages include more difficulties with exposure and retraction, as well as visualization, positioning and ergonomics of surgery.

Conclusions

Prone position lateral interbody fusion is an increasingly prevalent and useful surgical technique with several advantages and disadvantages when compared to lateral interbody fusion in the lateral decubitus position. There are several surgical indications and goals for which prone lateral interbody fusion may provide significant benefit when compared to other interbody fusion techniques.

Comparison of segmental lordosis gain of prone transpsoas (PTP) vs. lateral lumbar interbody fusion

INTRODUCTION

Lumbar interbody fusion is a standard method to treat certain degenerative conditions that are refractory to conservative treatments. LLIF reduces posterior muscle damage, can relieve neurological symptoms through indirect decompression, provides increased stability with its wider cages, and promotes more significant segmental lordosis than standard posterior techniques. However, the technique possesses its issues, such as unusual positioning, possible plexus-related symptoms, and median segmental lordosis correction. Trying to ease those issues, the idea of a prone transpsoas technique occurred.

METHODS

Retrospective, single-centric, comparative, and non-randomized study. The authors paired patients receiving lateral lumbar interbody fusion (LLIF) or prone transpsoas (PTP) to evaluate the technique's impact on the segmental lordosis correction. A correlation test selected the covariates for the matching. p-Values inferior to 0.05 were deemed significant.

RESULTS

Seventy-one patients were included in the analysis, 53 in the LLIF group and 18 in the PTP group. The significant covariates to the segmental lordosis correction were technique, preoperative segmental lordosis, cage position, and preoperative pelvic tilt. After the paring model, PTP showed significant segmental lordosis correction potential regarding the LLIF.

CONCLUSION

The prone transpsoas approach can significantly enhance the correction of segmental lordosis proportionated to the traditional LLIF approach.

Oblique lateral interbody fusion (OLIF) compared with unilateral biportal endoscopic lumbar interbody fusion (ULIF) for degenerative lumbar spondylolisthesis: a 2-year follow-up study

BACKGROUND

Oblique lumbar interbody fusion (OLIF) has been proven to be an effective method of indirect decompression for the treatment of Degenerative Lumbar Spondylolisthesis (DLS). However, its superiority over Unilateral biportal endoscopic Lumbar Interbody Fusion (ULIF) has not been reported yet. The current study aimed to compare the clinical and radiological outcomes of OLIF and ULIF in patients with DLS.

METHODS

A total of 107 patients were included in this study, divided into two groups according to the surgical methods with 45 patients treated by OLIF combined with anterolateral single screwrod fixation, and 62 patients treated by ULIF. To compare the perioperative parameters (blood loss, operation time, and postop hospitalization) and clinical (the Visual Analog Scale (VAS) scores of the low back pain and leg pain and the Oswestry Disability Index (ODI)) and radiological (disk height (DH), lumbar lordosis (LL), segmental lordosis (SL), the cross-sectional area (CSA) of the spinal canal) results of the two surgical approaches to evaluate their efficacy.

RESULTS

Compared with the ULIF group, the blood loss and operation time in the OLIF-AF group were significantly reduced, and the Postop hospitalization was comparable. The VAS scores in both groups were significantly improved compared to preop; however, the VAS score of low back pain in the OLIF-AF group was superior to that in ULIF group throughout the follow-up period (P < 0.05). The improvements in DH, LL, and Segmental angle were significantly lower in the ULIF group, and the expansion rate of CSA in the OLIF-AF group was superior to that in the ULIF group, but the difference was not statistically significant. The fusion rate in OLIF-AF group was significantly higher than that in ULIF group within 6 mo postop, and there was no significant difference at the last follow-up. The incidence of complications was comparable between the two groups, and there was no statistical difference.

CONCLUSIONS

Both OLIF-AF and ULIF achieved good short-term results in the treatment of DLS, and both surgical approaches are desirable. However, OLIF-AF has advantages over ULIF in terms of postoperative restoration of lumbar sagittal parameters and earlier intervertebral fusion. Long-term follow-up and larger clinical studies are needed to confirm this result.

What Are the Benefits of Lateral Lumbar Interbody Fusion on the Treatment of Adult Spinal Deformity: A Systematic Review and Meta-Analysis Deformity

STUDY DESIGN

A systematic review and meta-analysis.

OBJECTIVE

The purpose of this systematic review and meta-analysis was to compare the efficacy of lateral lumbar interbody fusion (LLIF) combined with posterior spinal fusion (PSF) with that of conventional PSF in the treatment of adult spinal deformity (ASD).

METHODS

A comprehensive literature search was performed for relevant studies in PubMed, EMBASE, Web of Science, and the Cochrane Library. Spinopelvic parameters, surgical data, complications, and clinical outcomes at the last follow-up were compared between patients with ASD who underwent LLIF combined with PSF (LLIF+PSF group) and those who underwent conventional PSF (only-PSF group).

RESULTS

Ten studies, comprising 621 patients with ASD (313 in the LLIF+PSF group and 308 in the only-PSF group), were included. The level of evidence was III for 7 studies and IV for 3 studies. There was no significant difference in the improvement in the visual analog scale score, systemic complication rate, and revision rate between groups. In the LLIF+PSF group, we noted a superior restoration of lumbar lordosis (weighted mean difference [WMD], 9.77; 95% confidence interval [CI] 7.10 to 12.44, P < .001), pelvic tilt (WMD, -2.50; 95% CI -4.25 to -.75, P = .005), sagittal vertical axis (WMD, -21.92; 95% CI -30.73 to -13.11, P < .001), and C7 plumb line-center sacral vertical line (WMD, -4.03; 95% CI -7.52 to -.54, P = .024); a lower estimated blood loss (WMD, -719.99; 95% CI -1105.02 to -334.96, P < .001) while a prolonged operating time (WMD, 104.89; 95% CI 49.36 to 160.43, P < .001); lower incidence of pseudarthrosis (risk ratio [RR], .26; 95% CI .08 to .79, P = .017) while higher incidence of neurologic deficits (RR, 2.04; 95% CI 1.27 to 3.25, P = .003); and a better improvement in Oswestry Disability Index score (WMD, -7.04; 95% CI -10.155 to -3.93, P < .001) and Scoliosis Research Society-22 total score (WMD, .27; 95% CI .11 to .42, P = .001). The level of evidence in this systematic review and meta-analysis was II.

CONCLUSION

Compared with conventional PSF, LLIF combined with PSF was associated with superior restoration of sagittal and coronal alignment, lower incidence of pseudarthrosis, better improvement in quality of life, and less surgical invasiveness in the treatment of ASD, albeit at the cost of prolonged surgical times and substantially high incidence of lower extremity symptoms. Surgeons should weigh the advantages and disadvantages of this procedure, and inform patients about its side effects.

Lumbar Interbody Fusion and Osteobiologics for Lumbar Fusion

Lumbar interbody fusion (LIF) is an excellent treatment option for a number of lumbar diseases. LIF can be performed through posterior, transforaminal, anterior, and lateral or oblique approaches. Each technique has its own pearls and pitfalls. Through LIF, segmental stabilization, neural decompression, and deformity correction can be achieved. Minimally invasive surgery has recently gained popularity and each LIF procedure can be performed using minimally invasive techniques to reduce surgery-related complications and improve early postoperative recovery. Despite advances in surgical technology, surgery-related complications after LIF, such as pseudoarthrosis, have not yet been overcome. Although autogenous iliac crest bone graft is the gold standard for spinal fusion, other bone substitutes are available to enhance fusion rate and reduce complications associated with bone harvest. This article reviews the surgical procedures and characteristics of each LIF and the osteobiologics utilized in LIF based on the available evidence.

Equipoise for Lateral Access Surgery

OBJECTIVE

To investigate the use of lateral access surgery among surgeons from the Asia-Pacific region to determine equipoise for areas of contentious use.

METHODS

A questionnaire was distributed to members of the Asia Pacific Spine Society. Surgeons were asked about their past experiences with lateral access surgery, including their advantages and disadvantages, specific surgical strategies, choices in implant-related factors, order of levels to operate on in multilevel reconstruction surgery, and postoperative complications.

RESULTS

A total of 69 of 102 surgeons (67.6%) had performed lateral access surgery previously. In total, 56 participating surgeons (54.9%) agreed that anterior column reconstruction via lateral access is most of time superior to transforaminal lumbar interbody fusion and other techniques. Surgeons would consider laminectomy instead of indirect decompression in the presence of severe central or lateral recess stenosis, thickened ligamentum flavum, and facet joint hypertrophy. For the order of levels to operate on in multiple level reconstruction for deformity, where 1 stands for L3-L4 or higher, 2 stands for L4-L5, and 3 stands for L5-S1, 2-1-3 (28/95, 29.5%) was most common, followed by 1-2-3 (26/95, 27.4%), and 3-2-1 (21/95, 22.1%).

CONCLUSIONS

Lateral access surgery is seeing greater use in the Asia-Pacific region, especially in upper middle- to high-income countries, whereas keenness of surgeons who practice in lower middle- to low-income countries can be improved by more training, resources, and reasonable cost. A high percentage of surgeons do not consider indirect decompression for spinal stenosis. There was no consensus on the order of levels in multiple level reconstruction for deformity.

Does the Position of Cage Affect the Clinical Outcome of Lateral Interbody Fusion in Lumbar Spinal Stenosis?

STUDY DESIGN

A retrospective study.

OBJECTIVE

This study aims to identify the ideal cage position in lateral lumbar interbody fusion (LLIF) and to investigate if the posterior instrumentation would affect the indirect decompression.

METHODS

Patients underwent 2-stage surgeries: stage I was LLIF and stage II was percutaneous pedicle screws fixation after 1 week. Anterior disc height (ADH), posterior disc height (PDH), left and right foraminal height (FH), and segmental angle (SA) were measured on lateral computed tomography reconstructions. The cross-sectional area of the thecal sac (CSA) was determined by the outlined area of the thecal sac on a T2-weighted axial magnetic resonance imaging. The patients were subgroups according to the cage position: the anterior (cage located at the anterior 1/3 of disc space) and posterior groups (cage located at the posterior 2/3 of disc space). P values <.05 were considered significant.

RESULTS

This study included 46 patients and 71 surgical levels. After stage I LLIF, significant increase in ADH, PDH, bilateral FH was found in both 2 subgroups, as well as the CSA (all Ps < .01). SA increased 2.84° ± 3.2° in the anterior group after stage I LLIF and increased 0.81° ± 3.1° in the posterior group (P = .013). After stage II surgery, SA was similar between the anterior and posterior groups (P = .20).

CONCLUSION

The anteriorly placed cage may provide better improvement of anterior disc height and segmental angle after stand-alone LLIF surgery. After the second stage posterior instrumentation, the cage position would not affect the segmental angle or foraminal height.

Comparison of Outcomes Between Single-level Lateral Lumbar Interbody Fusion and Transforaminal Lumbar Interbody Fusion: A Meta-analysis and Systematic Review

STUDY DESIGN

This is a meta-analysis and systematic review of the available literature.

OBJECTIVE

This study aims to compare the clinical and radiologic outcomes of single-level lateral lumbar interbody fusion (LLIF) with single-level transforaminal lumbar interbody fusion (TLIF).

SUMMARY OF BACKGROUND DATA

In the treatment of adult spinal deformity, LLIF allows interbody fusion while avoiding complications associated with an anterior or transforaminal approach, although the clinical outcomes of LLIF compared with other approaches have not been well established.

METHODS

We searched PubMed, Embase, and Scopus for 385 unique studies. On the basis of our exclusion criteria, 8 studies remained for our systematic review. Data were analyzed using Review Manager 5.3 using Mantel-Haenszel statistics and random effect models. This study identified self-reported Visual Analog Scale (VAS), Oswestry Disability Index, length of stay, blood loss, complication rate, and radiologic parameters (disk height, lumbar lordosis, segmental lordosis).

RESULTS

Our meta-analysis showed that LLIF contributed to decreased blood loss [mean difference (MD)=-67.62 mL, 95% confidence interval (CI): -104 to -30.90, P<0.001], superior restoration of segmental lordosis (MD=1.91 degrees, 95% CI: 0.71-3.10, P=0.002), lumbar lordosis (MD=1.95 degrees, 95% CI: 0.15-3.74, P=0.03), and disk height (MD=2.18 mm, 95% CI: 1.18-3.17, P<0.001) when compared with TLIF. However, current data suggests no significant difference in clinical outcomes between LLIF and TLIF based on overall complication rates (P=0.22), length of hospital stay (P=0.65), postoperative Oswestry Disability Index (P=0.13), postoperative VAS Back Pain (P=0.47) and VAS Leg Pain (P=0.16).

CONCLUSIONS

LLIF is an increasingly popular option for single-level anterior column reconstruction. When compared with single-level TLIF, single-level LLIF is associated with greater changes in lumbar lordosis and disk height. The single-level LLIF is a viable alternative to TLIF, demonstrating comparable clinical outcomes and better restoration of spinopelvic parameters.

LEVEL OF EVIDENCE

Level III.

Lateral lumbar interbody fusion in adult spine deformity - A review of literature

INTRODUCTION

Surgery for adult spine deformity presents a challenging issue for spinal surgeons with high morbidity rates reported in the literature. The minimally invasive lateral approach aims at reducing these complications while maintaining similar outcomes as associated with open spinal surgeries. The aim of this paper is to review the literature on the use of lateral lumbar interbody fusion in the cases of adult spinal deformity.

METHODS

A literature review was done using the healthcare database Advanced Research on NICE and NHS website using Medline. Search terms were "XLIF" or "LLIF" or "DLIF" or "lateral lumbar interbody fusion" or "minimal invasive lateral fusion" and "adult spinal deformity" or "spinal deformity".

RESULTS

A total of 417 studies were considered for the review and 44 studies were shortlisted after going through the selection criteria. The data of 1722 patients and 4057 fusion levels were analysed for this review. The mean age of the patients was 65.18 years with L4/5 being the most common level fused in this review. We found significant improvement in the radiological parameters (lordosis, scoliosis, and disk height) in the pooled data. Transient neurological symptoms and cage subsidence were the two most common complications reported.

CONCLUSION

LLIF is a safe and effective approach in managing adult spinal deformity with low morbidity and acceptable complication rates. It can be used alone for lower grades of deformity and as an adjuvant procedure to decrease the magnitude of open surgeries in high-grade deformities.

Transforaminal Lumbar Interbody Fusion (TLIF) versus Oblique Lumbar Interbody Fusion (OLIF) in Interbody Fusion Technique for Degenerative Spondylolisthesis: A Systematic Review and Meta-Analysis

Preoperative pathology requiring fusion surgery has a great impact on postoperative outcomes. However, the previous clinical and meta-analysis studies did not control for the pathology. In this systematic review, the authors aimed to compare oblique lumbar interbody fusion (OLIF) with transforaminal interbody fusion (TLIF) as an interbody fusion technique in lumbar fusion surgery for patients with degenerative spondylolisthesis (DS). We systematically searched for relevant articles in the available databases. Among the 3022 articles, three studies were identified and met the inclusion criteria. In terms of radiological outcome, the amount of disc height restoration was greater in the OLIF group than in the TLIF group, but there was no significant difference between the two surgical techniques (p = 0.18). In the clinical outcomes, the pain improvement was not significantly different between the two surgical techniques. In terms of surgical outcomes, OLIF resulted in a shorter length of hospital stay and less blood loss than TLIF (p < 0.0001 and p = 0.02, respectively). The present meta-analysis indicated no significant difference in clinical, radiological outcomes, and surgical time between TLIF and OLIF for DS, but the lengths of hospital stay and blood loss were better in OLIF than TLIF. Though encouraging, these findings were based on low-quality evidence from a small number of retrospective studies that are prone to bias.

Segmental Arteries and Veins at Higher Lumbar Levels Can Intersect the Adjacent Caudal Intervertebral Disc in the Anterior Part of the Spinal Column: A Cadaveric Analysis

Study Design

A cadaveric study.

Purpose

To investigate the anatomical features of segmental arteries and veins in the anterior part of the spinal column to prevent segmental vessel injury.

Overview of Literature

The lateral transpsoas approach to the lumbar intervertebral discs (IVD) is associated with the risk of segmental vessel injury. Previous studies have described the vascular anatomy on the lateral part of the vertebral body. However, there are no studies that describe the segmental vessels on its anterior aspect. Here, we report the important anatomical features of the segmental arteries and veins that can intersect the anterior part of the IVD. These vessels are considered at risk of vascular injury when placing the anterior retractors during lateral lumbar interbody fusion or cutting the anterior longitudinal ligament during anterior column realignment.

Methods

Five formalin-embalmed human cadavers were used. We assessed the proportion of segmental arteries and veins that intersected the IVD in the L2–L5 range and their course on the anterior part of the spinal column.

Results

The segmental arteries and veins commonly intersect the anterior part of the IVD (artery, 28.1%; vein, 42.1%). Seven of 10 (70%) segmental arteries at L2 intersected the IVD, but only one artery intersected the IVD at L3 and L4. The proportions of segmental veins that intersected the IVD were 60%, 50%, and 16.7% at L2, L3, and L4, respectively.

Conclusions

The segmental arteries and veins frequently intersect the IVD in the anterior part of the spinal column. Therefore, it is necessary to consider these individual anatomical features to prevent vascular damage during lateral lumbar interbody fusion surgery.

Improvement in Gait Pattern and its Relationship With Preoperative Pelvic Compensation After Surgery in Patients With Sagittal Plane Deformity

STUDY DESIGN

Prospective observational study.

OBJECTIVE

The aim of this study was to investigate the improvement in gait parameters after surgery and whether corrective surgery for sagittal imbalance would be influenced by preoperative pelvic compensation.

SUMMARY OF BACKGROUND DATA

There have been no other studies investigating the influence of preoperative pelvic compensation on surgical outcomes.

METHODS

A total of 32 patients who were scheduled to undergo corrective surgery for sagittal plane deformity were included and were followed-up for 1 year after surgery. Radiological parameters were measured on biplanar full-body imaging. Before surgery and 6 months after surgery, three-dimensional motion analyses were performed to estimate center of gravity (CoG) deviation from the center of mass (CoM), mean trunk kyphosis (TK) angle, gait deviation index (GDI), and kinematic parameters. Before surgery, the patients were classified into CoG+ and CoG- groups. "+" and "-" representing increases and decreases in the distance of CoG from CoM of the pelvic segment from first to third trials, respectively. Oswestry Disability Index (ODI) and EuroQol-5D (EQ-5D) were measured for 1 year after surgery.

RESULTS

All radiological parameters improved significantly after surgery. For gait parameters, CoG from CoM, mean TK angle, and minimum angle of the hip and knee joints in the stance phase during walking were significantly decreased after surgery and GDI scores significantly improved after surgery. The mean changes of the CoG distance from the CoG and the mean TK from first to third trials of gait analysis significantly decreased postoperatively. There were no significant differences in ODI and EQ-5D scores over 1-year follow-up assessment between CoG+ and CoG- groups.

CONCLUSION

Preoperative abnormal stooping gait, and progressive worsening of sagittal imbalance in patients with sagittal plane deformity improved after corrective surgery. Patients with preoperative dynamic sagittal imbalance could have similar surgical results to those without it after corrective surgery.

LEVEL OF EVIDENCE

3.

Lumbar Interbody Fusion: Techniques, Pearls and Pitfalls

Lumbar interbody fusion (LIF) is an effective and popular surgical procedure for the management of various spinal pathologies, especially degenerative diseases. Currently, LIF can be performed with posterior, transforaminal, anterior, and lateral approaches by open surgery or minimally invasive surgery (MIS). Each technique has its own advantages and disadvantages. In general, posterior LIF is a well-established procedure with good fusion rates and low complication rates but is limited by the possibility of iatrogenic injury to the neural structures and paraspinal muscles. Transforaminal LIF is frequently performed using an MIS technique and has an advantage of reducing these iatrogenic injuries. Anterior LIF (ALIF) can restore the disk height and sagittal alignment but has inherent approach-related challenges such as visceral and vascular complications. Lateral LIF and oblique LIF are performed using an MIS technique and have shown postoperative outcomes similar to ALIF; however, these approaches carry a risk of injury to psoas, lumbar plexus, and vascular structures. Herein, we provide a detailed description of the surgical procedures of each LIF technique. We shall then consider the pearls and pitfalls, as well as propose surgical indications and contraindications based on the available evidence in the literatures.

Patient-reported Quality of Life Following Posterior Lumbar Interbody Fusion or Indirect Decompression Using Lateral Lumbar Interbody Fusion

STUDY DESIGN

A retrospective review of prospectively collected data.

OBJECTIVE

The aim of this study was to compare quality of life (QOL) outcomes of posterior lumbar interbody fusion (PLIF) with lateral lumbar interbody fusion (LLIF) using reports from patients obtained at the 2-year postoperative follow-up.

SUMMARY OF BACKGROUND DATA

Indirect decompression with LLIF is used to treat degenerative lumbar diseases that require neural decompression. However, the difference in improvement in QOL following indirect decompression compared with direct neural decompression using PLIF is unclear.

METHODS

We enrolled 284 consecutive patients with degenerative lumbar spondylolisthesis in the present study, 203 who underwent PLIF and 81 who underwent LLIF. All patients completed a minimum of 2 years of follow-up. We evaluated the effectiveness of surgery in each category of the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ).

RESULTS

The results of preoperative JOABPEQ and the severity of thecal sac stenosis were not significantly different between PLIF and LLIF, neither was the rate of perioperative complications (14.8% and 15.4% for the PLIF and LLIF groups, respectively; P = 0.91). The effectiveness at 2 years postoperatively was almost the same for all five domains of the JOABPEQ: 62.6% and 68.9% for pain-related disorders (P = 0.34), 38.3% and 42.7% for lumbar spine dysfunction (P = 0.51), 65.8% and 67.5% for gait disturbance (P = 0.79), 53.5% and 48.8% for social life dysfunction (P = 0.47), and 29.1% and 33.3% for psychological disorders (P = 0.48) following PLIF and LLIF, respectively. Visual analogue scale results for back and lower-limb pain and numbness of the lower limbs were almost the same for both groups. No significant differences were observed in terms of perioperative complications and radiographical outcomes.

CONCLUSION

Indirect decompression using LLIF improves QOL and radiographical outcomes to a comparable degree as direct decompression via PLIF.

LEVEL OF EVIDENCE

4.

Lateral approach corpectomy and reconstruction after anterior longitudinal ligament release in cases with fixed kyphosis: A technical note and a preliminary case series

Lateral approach corpectomy is a useful surgical technique for adult spinal deformity with vertebral deformity. However, in cases with anterior ankylosing over adjacent vertebrae, it is hard to achieve ideal correction without posterior column resection. To minimize surgical invasiveness, we have developed a method for lateral approach corpectomy and reconstruction after anterior longitudinal ligament release (LCRA) in such cases. The aim of the current study is to describe LCRA, and investigate surgical invasiveness, sagittal correction and perioperative complications in this surgery. The subjects were three patients (all female, average age 69.0 years old) with adult spinal deformity with severe fixed kyphosis who underwent LCRA and posterior fixation with pedicle screws. The primary disease was osteoporotic vertebral fracture in all patients. The operative levels were T12 in 2 cases and L2 in 1 case. The operative time and estimated blood loss were 442.3 ± 51.9 min and 875.7 ± 397.5 mL, respectively. Local kyphotic deformity was well corrected from 54.2 ± 4.3° preoperatively to 10.1 ± 3.7° in these surgeries (p < 0.001). There were surgical complications of dural tear and postoperative hemothorax in one case each. These outcomes suggest that LCRA gives good sagittal correction in cases with fixed kyphosis after osteoporotic vertebral fracture, and that this method is a viable surgical option for correction of fixed kyphosis.

Indirect Decompression on MRI Chronologically Progresses After Immediate Postlateral Lumbar Interbody Fusion: The Results From a Minimum of 2 Years Follow-Up

MINI: On magnetic resonance imaging, indirect decompression using lateral lumbar interbody fusion and posterior fixation was confirmed immediately after surgery and also continuously progressed after surgery, particularly during the first 6 months. Thecal sac enlargement was also confirmed, and is suspected to be caused by the atrophy of the ligamentum flavum and the disc.

STUDY DESIGN

A prospective cohort study.

OBJECTIVE

The aim of this study was to investigate radiographical changes related to indirect decompression using lateral lumbar interbody fusion (LLIF) with posterior fixation.

SUMMARY OF BACKGROUND DATA

Indirect lumbar decompression via LLIF is used to treat degenerative lumbar diseases requiring neural decompression. Although evidence suggests that thecal sac enlargement follows shortly after surgery, few studies have described the postoperative changes on MRIs.

METHODS

This study involved 102 patients who underwent indirect decompression at 136 levels, with LLIF and posterior fixation. Magnetic resonance imaging (MRIs) were collected preoperatively and several times postoperatively (over a 2-year period starting immediately after surgery). We then quantified the cross-sectional areas of the thecal sac and ligamentum flavum, as well as the anteroposterior diameter of disc bulging, and qualitatively assessed lumbar spinal stenosis according to a modified version of Schizas' classification [Grades A (mild) to C (severe)]. The Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) was used for the assessment of the clinical symptoms.

RESULTS

All changes were observable immediately after surgery, progressed over time, and were significantly different statistically at 2 years after surgery. The thecal sac was significantly larger (189% of preoperative; P < 0.0001), while the ligamentum flavum and disc bulge were significantly smaller [58.9% and 67.3% of preoperative (P < 0.001), respectively]. The number of patients with grade C (severe) lumbar stenosis also dropped significantly (preoperative, 17.6%; 2 years postoperative, 0%). There were no significant differences in JOABPEQ results at 6 months, 1 year, and 2 years postsurgery.

CONCLUSION

Indirect decompression produces immediate positive results that continue to improve over time. The cross-sectional area of the thecal sac doubled by 2 years after surgery, and the ligamentum flavum cross-sectional area and disc bulging both shrank significantly. At the same time, however, postoperative radiographical improvements do not appear to correlate with clinical symptoms.

LEVEL OF EVIDENCE

3.