Biomechanics of Lateral Interbody Spacers: Going Wider for Going Stiffer

This study investigates the biomechanical stability of a large interbody spacer inserted by a lateral approach and compares the biomechanical differences with the more conventional transforaminal interbody fusion (TLIF), with and without supplemental pedicle screw (PS) fixation. Twenty-four L2-L3 functional spinal units (FSUs) were tested with three interbody cage options: (i) 18 mm XLIF cage, (ii) 26 mm XLIF cage, and (iii) 11 mm TLIF cage. Each spacer was tested without supplemental fixation, and with unilateral and bilateral PS fixation. Specimens were subjected to multidirectional nondestructive flexibility tests to 7.5 N·m. The range of motion (ROM) differences were first examined within the same group (per cage) using repeated-measures ANOVA, and then compared between cage groups. The 26 mm XLIF cage provided greater stability than the 18 mm XLIF cage with unilateral PS and 11 mm TLIF cage with bilateral PS. The 18 mm XLIF cage with unilateral PS provided greater stability than the 11 mm TLIF cage with bilateral PS. This study suggests that wider lateral spacers are biomechanically stable and offer the option to be used with less or even no supplemental fixation for interbody lumbar fusion.

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Simultaneous Lateral Interbody Fusion and Posterior Percutaneous Instrumentation: Early Experience and Technical Considerations

BioMed Research International ◽

10.1155/2015/458284 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 6

Author(s):

Doniel Drazin ◽

Terrence T. Kim ◽

J. Patrick Johnson

Keyword(s):

Interbody Fusion ◽

Lumbar Fusion ◽

Posterior Instrumentation ◽

Lateral Approach ◽

Control Group ◽

Percutaneous Instrumentation ◽

Lateral Interbody Fusion ◽

Simultaneous Group ◽

Simultaneous Procedures ◽

Lateral Interbody

Lumbar fusion surgery involving lateral lumbar interbody graft insertion with posterior instrumentation is traditionally performed in two stages requiring repositioning. We describe a novel technique to complete the circumferential procedure simultaneously without patient repositioning. Twenty patients diagnosed with worsening back pain with/without radiculopathy who failed exhaustive conservative management were retrospectively reviewed. Ten patients with both procedures simultaneously from a single lateral approach and 10 control patients with lateral lumbar interbody fusion followed by repositioning and posterior percutaneous instrumentation were analyzed. Pars fractures, mobile grade 2 spondylolisthesis, and severe one-level degenerative disk disease were matched between the two groups. In the simultaneous group, avoiding repositioning leads to lower mean operative times: 130 minutes (versus control 190 minutes;p=0.009) and lower intraoperative blood loss: 108 mL (versus 93 mL; NS). Nonrepositioned patients were hospitalized for an average of 4.1 days (versus 3.8 days; NS). There was one complication in the control group requiring screw revision. Lateral interbody fusion and percutaneous posterior instrumentation are both readily accomplished in a single lateral decubitus position. In select patients with adequately sized pedicles, performing simultaneous procedures decreases operative time over sequential repositioning. Patient outcomes were excellent in the simultaneous group and comparable to procedures done sequentially.

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Minimally invasive lateral interbody fusion for the treatment of rostral adjacent-segment lumbar degenerative stenosis without supplemental pedicle screw fixation

Journal of Neurosurgery Spine ◽

10.3171/2014.8.spine13841 ◽

2014 ◽

Vol 21 (6) ◽

pp. 861-866 ◽

Cited By ~ 31

Author(s):

Michael Y. Wang ◽

Ram Vasudevan ◽

Stefan A. Mindea

Keyword(s):

Minimally Invasive ◽

Interbody Fusion ◽

Lumbar Fusion ◽

Ct Scanning ◽

Lateral Approach ◽

Leg Pain ◽

Adjacent Segment ◽

Lateral Interbody Fusion ◽

The Mean ◽

Lateral Interbody

Object Adjacent-segment degeneration and stenosis are common in patients who have undergone previous lumbar fusion. Treatment typically involves a revision posterior approach, which requires management of postoperative scar tissue and previously implanted instrumentation. A minimally invasive lateral approach allows the surgeon to potentially reduce the risk of these hazards. The technique relies on indirect decompression to treat central and foraminal stenosis and placement of a graft with a large surface area to promote robust fusion and stability in concert with the surrounding tensioned ligaments. The goal in this study was to determine if lateral interbody fusion without supplemental pedicle screws is effective in treating adjacent-segment disease. Methods For a 30-month study period at two institutions, the authors obtained all cases of lumbar fusion with new back and leg pain due to adjacent-segment stenosis and spondylosis failing conservative measures. All patients had undergone minimally invasive lateral interbody fusion from the side of greater leg pain without supplemental pedicle screw fixation. Patients were excluded from the study if they had undergone surgery for a nondegenerative etiology such as infection or trauma. They were also excluded if the intervention involved supplemental posterior instrumented fusion with transpedicular screws. Postoperative metrics included numeric pain scale (NPS) scores for leg and back pain. All patients underwent dynamic radiographs and CT scanning to assess stability and fusion after surgery. Results During the 30-month study period, 21 patients (43% female) were successfully treated using minimally invasive lateral interbody fusion without the need for subsequent posterior transpedicular fixation. The mean patient age was 61 years (range 37–87 years). Four patients had two adjacent levels fused, while the remainder had single-level surgery. All patients underwent surgery without conversion to a traditional open technique, and recombinant human bone morphogenetic protein–2 was used in the interbody space in all cases. The mean follow-up was 23.6 months. The mean operative time was 86 minutes, and the mean blood loss was 93 ml. There were no major intraoperative complications, but one patient underwent subsequent direct decompression in a delayed fashion. The leg pain NPS score improved from a mean of 6.3 to 1.9 (p < 0.01), and the back pain NPS score improved from a mean of 7.5 to 2.9 (p < 0.01). Intervertebral settling averaged 1.7 mm. All patients had bridging bone on CT scanning at the last follow-up, indicating solid bony fusion. Conclusions Adjacent-segment stenosis and spondylosis can be treated with a number of different operative techniques. Lateral interbody fusion provides an attractive alternative with reduced blood loss and complications, as there is no need to re-explore a previous laminectomy site. In this limited series a minimally invasive lateral approach provided high fusion rates when performed with osteobiological adjuvants.

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Stand-Alone Lateral Interbody Fusion for the Treatment of Low-Grade Degenerative Spondylolisthesis

The Scientific World JOURNAL ◽

10.1100/2012/456346 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 77

Author(s):

Luis Marchi ◽

Nitamar Abdala ◽

Leonardo Oliveira ◽

Rodrigo Amaral ◽

Etevaldo Coutinho ◽

...

Keyword(s):

Minimally Invasive ◽

Interbody Fusion ◽

Degenerative Spondylolisthesis ◽

Lateral Approach ◽

Low Grade ◽

Mean Values ◽

Single Level ◽

Lateral Interbody Fusion ◽

Cage Subsidence ◽

Lateral Interbody

The purpose of this paper was to investigate the stand-alone lateral interbody fusion as a minimally invasive option for the treatment of low-grade degenerative spondylolisthesis with a minimum 24-month followup. Prospective nonrandomized observational single-center study. 52 consecutive patients (67.6±10 y/o; 73.1% female;27.4±3.4 BMI) with single-level grade I/II single-level degenerative spondylolisthesis without significant spine instability were included. Fusion procedures were performed as retroperitoneal lateral transpsoas interbody fusions without screw supplementation. The procedures were performed in average 73.2 minutes and with less than 50cc blood loss. VAS and Oswestry scores showed lasting improvements in clinical outcomes (60% and 54.5% change, resp.). The vertebral slippage was reduced in 90.4% of cases from mean values of 15.1% preoperatively to 7.4% at 6-week followup (P<0.001) and was maintained through 24 months (7.1%,P<0.001). Segmental lordosis (P<0.001) and disc height (P<0.001) were improved in postop evaluations. Cage subsidence occurred in 9/52 cases (17%) and 7/52 cases (13%) spine levels needed revision surgery. At the 24-month evaluation, solid fusion was observed in 86.5% of the levels treated. The minimally invasive lateral approach has been shown to be a safe and reproducible technique to treat low-grade degenerative spondylolisthesis.

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Biomechanical analysis of stand-alone lumbar interbody cages versus 360° constructs: an in vitro and finite element investigation

Journal of Neurosurgery Spine ◽

10.3171/2021.9.spine21558 ◽

2021 ◽

pp. 1-9

Keyword(s):

Interbody Fusion ◽

Posterior Instrumentation ◽

Axial Rotation ◽

Posterior Fixation ◽

Interbody Cage ◽

Lateral Bending ◽

Flexion Extension ◽

Lateral Interbody ◽

Flexion And Extension

OBJECTIVE Low fusion rates and cage subsidence are limitations of lumbar fixation with stand-alone interbody cages. Various approaches to interbody cage placement exist, yet the need for supplemental posterior fixation is not clear from clinical studies. Therefore, as prospective clinical studies are lacking, a comparison of segmental kinematics, cage properties, and load sharing on vertebral endplates is needed. This laboratory investigation evaluates the mechanical stability and biomechanical properties of various interbody fixation techniques by performing cadaveric and finite element (FE) modeling studies. METHODS An in vitro experiment using 7 fresh-frozen human cadavers was designed to test intact spines with 1) stand-alone lateral interbody cage constructs (lateral interbody fusion, LIF) and 2) LIF supplemented with posterior pedicle screw-rod fixation (360° constructs). FE and kinematic data were used to validate a ligamentous FE model of the lumbopelvic spine. The validated model was then used to evaluate the stability of stand-alone LIF, transforaminal lumbar interbody fusion (TLIF), and anterior lumbar interbody fusion (ALIF) cages with and without supplemental posterior fixation at the L4–5 level. The FE models of intact and instrumented cases were subjected to a 400-N compressive preload followed by an 8-Nm bending moment to simulate physiological flexion, extension, bending, and axial rotation. Segmental kinematics and load sharing at the inferior endplate were compared. RESULTS The FE kinematic predictions were consistent with cadaveric data. The range of motion (ROM) in LIF was significantly lower than intact spines for both stand-alone and 360° constructs. The calculated reduction in motion with respect to intact spines for stand-alone constructs ranged from 43% to 66% for TLIF, 67%–82% for LIF, and 69%–86% for ALIF in flexion, extension, lateral bending, and axial rotation. In flexion and extension, the maximum reduction in motion was 70% for ALIF versus 81% in LIF for stand-alone cases. When supplemented with posterior fixation, the corresponding reduction in ROM was 76%–87% for TLIF, 86%–91% for LIF, and 90%–92% for ALIF. The addition of posterior instrumentation resulted in a significant reduction in peak stress at the superior endplate of the inferior segment in all scenarios. CONCLUSIONS Stand-alone ALIF and LIF cages are most effective in providing stability in lateral bending and axial rotation and less so in flexion and extension. Supplemental posterior instrumentation improves stability for all interbody techniques. Comparative clinical data are needed to further define the indications for stand-alone cages in lumbar fusion surgery.

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Simultaneous Robotic Single-Position Surgery With Oblique Lumbar Interbody Fusion With Software Planning: 2-Dimensional Operative Video

Operative Neurosurgery ◽

10.1093/ons/opaa451 ◽

2021 ◽

Author(s):

Martin H Pham ◽

Jillian Plonsker ◽

Luis D Diaz-Aguilar ◽

Joseph A Osorio ◽

Ronald A Lehman

Keyword(s):

Interbody Fusion ◽

Posterior Instrumentation ◽

Spinal Instrumentation ◽

Lateral Position ◽

Lateral Approach ◽

Lumbar Interbody Fusion ◽

Robotic Platform ◽

Patient Consent ◽

Oblique Lumbar Interbody Fusion ◽

Lateral Interbody

Abstract The use of robotic guidance for spinal instrumentation is promising for its ability to offer the advantages of precision, accuracy, and reproducibility. This has become even more important in the era of lateral interbody surgery because spinal robotics opens up the possibility of a straightforward workflow for single-position surgery in the lateral position. We present here a case of a 72-yr-old woman who presented with an L4-5 spondylolisthesis with axial back pain and radiculopathy. She subsequently underwent an L4-5 oblique lumbar interbody fusion with L4-5 bilateral posterior instrumentation in a single lateral position (Mazor X Stealth Edition, Medtronic Sofamor Danek, Medtronic Inc, Dublin, Ireland). Due to the oblique lateral approach and posterior robotic assistance, both surgeons were able to work simultaneously for increased efficiency. To our knowledge, this is the first video demonstrating a two-surgeon simultaneous robotic single-position surgery with oblique lumbar interbody fusion using a spinal robotic platform. There is no identifying information in this video. Patient consent was obtained for the surgical procedure and for publishing of the material included in the video.

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A novel approach to the lumbar sympathetic chain: lateral access

Neurosurgical FOCUS ◽

10.3171/2013.v2.focus13204 ◽

2013 ◽

Vol 35 (v2supplement) ◽

pp. Video12

Author(s):

Shaun D. Rodgers ◽

John A. Engler ◽

Noel L. Perin

Keyword(s):

Interbody Fusion ◽

Botulinum Toxin Injection ◽

Treatment Options ◽

Lateral Approach ◽

Sympathetic Chain ◽

Efficacy And Safety ◽

Social Psychological ◽

Novel Approach ◽

Lateral Interbody

Plantar hyperhydrosis is a disabling condition of excessive, symmetric, focal sweating of the feet with social, psychological, and medical implications. Treatment options include topical agents, iontophoresis, botulinum toxin injection, and surgical disruption of the lumbar sympathetic chain.Surgical corridors include transperitoneal and retroperitoneal approaches. We report our technique with a novel minimally invasive lateral retroperitoneal approach commonly used for lateral interbody fusions. The lateral approach for sectioning of the sympathetic chain in the treatment of hyperhydrosis appears safe. The approach may be advantageous for the patient and surgeons familiar with lateral interbody fusion. Further studies may elucidate the long term efficacy and safety of the lateral approach.The video can be found here: http://youtu.be/Q82SGpmAXng.

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Biomechanics of lateral lumbar interbody fusion constructs with lateral and posterior plate fixation

Journal of Neurosurgery Spine ◽

10.3171/2013.11.spine13617 ◽

2014 ◽

Vol 20 (3) ◽

pp. 291-297 ◽

Cited By ~ 31

Author(s):

Guy R. Fogel ◽

Rachit D. Parikh ◽

Stephen I. Ryu ◽

Alexander W. L. Turner

Keyword(s):

Interbody Fusion ◽

Plate Fixation ◽

Spinous Process ◽

Pedicle Screws ◽

Axial Rotation ◽

Interbody Cage ◽

Lateral Bending ◽

Lateral Plate ◽

Flexion Extension ◽

Supplemental Fixation

Object Lumbar interbody fusion is indicated in the treatment of degenerative conditions. Laterally inserted interbody cages significantly decrease range of motion (ROM) compared with other cages. Supplemental fixation options such as lateral plates or spinous process plates have been shown to provide stability and to reduce morbidity. The authors of the current study investigate the in vitro stability of the interbody cage with a combination of lateral and spinous process plate fixation and compare this method to the established bilateral pedicle screw fixation technique. Methods Ten L1–5 specimens were evaluated using multidirectional nondestructive moments (± 7.5 N·m), with a custom 6 degrees-of-freedom spine simulator. Intervertebral motions (ROM) were measured optoelectronically. Each spine was evaluated under the following conditions at the L3–4 level: intact; interbody cage alone (stand-alone); cage supplemented with lateral plate; cage supplemented with ipsilateral pedicle screws; cage supplemented with bilateral pedicle screws; cage supplemented with spinous process plate; and cage supplemented with a combination of lateral plate and spinous process plate. Intervertebral rotations were calculated, and ROM data were normalized to the intact ROM data. Results The stand-alone laterally inserted interbody cage significantly reduced ROM with respect to the intact state in flexion-extension (31.6% intact ROM, p < 0.001), lateral bending (32.5%, p < 0.001), and axial rotation (69.4%, p = 0.002). Compared with the stand-alone condition, addition of a lateral plate to the interbody cage did not significantly alter the ROM in flexion-extension (p = 0.904); however, it was significantly decreased in lateral bending and axial rotation (p < 0.001). The cage supplemented with a lateral plate was not statistically different from bilateral pedicle screws in lateral bending (p = 0.579). Supplemental fixation using a spinous process plate was not significantly different from bilateral pedicle screws in flexion-extension (p = 0.476). The combination of lateral plate and spinous process plate was not statistically different from the cage supplemented with bilateral pedicle screws in all the loading modes (p ≥ 0.365). Conclusions A combination of lateral and spinous process plate fixation to supplement a laterally inserted interbody cage helps achieve rigidity in all motion planes similar to that achieved with bilateral pedicle screws.

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Review of Risks and Complications of Extreme Lateral Interbody Fusion (XLIF)

Surgical Neurology International ◽

10.25259/sni_559_2019 ◽

2019 ◽

Vol 10 ◽

pp. 237 ◽

Cited By ~ 4

Author(s):

Nancy E. Epstein

Keyword(s):

Interbody Fusion ◽

Conflicts Of Interest ◽

Lumbar Fusion ◽

Significant Risk ◽

Posterior Lumbar Interbody Fusion ◽

Lumbar Plexus ◽

Abdominal Muscles ◽

Vascular Injuries ◽

Lumbar Interbody Fusion ◽

Lateral Interbody

Background: Extreme lateral interbody fusions (XLIF) and Minimally Invasive (MIS) XLIF were developed to limit the vascular injuries associated with anterior lumbar interbody fusion (ALIF), and minimize the muscular/ soft tissue trauma attributed to transforaminal lumbar interbody fusion (TLIF), posterior lumbar interbody fusion (PLIF), and posterolateral lumbar fusion (PLF). Methods: Nevertheless, XLIF/MIS XLIF pose significant additional risks and complications that include; multiple nerve injuries (e.g. lumbar plexus, ilioinguinal, iliohypogastric, genitofemoral, lateral femoral cutaneous, and subcostals (to the anterior abdominal muscles: abdominal oblique), and sympathectomy), major vascular injuries, bowel perforations/postoperative ileus, seromas, pseudarthrosis, subsidence, and reoperations. Results: The risks of neural injury with XLIF/MIS XLIF (up to 30-40%) are substantially higher than for TLIF, PLIF, PLF, and ALIF. These neural injuries included: lumbar plexus injuries (13.28%); new sensory deficits (0-75% (21.7%-40%); permanent 62.5%); motor deficits (0.7-33.6%-40%); iliopsoas weakness (9%-31%: permanent 5%), anterior thigh/groin pain (12.5-34%), and sympathectomy (4%-12%). Additional non-neurological complications included; subsidence (10.3%-13.8%), major vascular injuries (0.4%), bowel perforations, recurrent seroma, malpositioning of the XLIF cages, a 45% risk of cage-overhang, pseudarthrosis (7.5%), and failure to adequately decompress stenosis. In one study, reviewing 20 publications and involving 1080 XLIF patients, the authors observed “Most (XLIF) studies are limited by study design, sample size, and potential conflicts of interest.” Conclusion: Many new neurological deficits and other adverse events/complications are attributed to MIS XLIF/ XLIF. Shouldn’t these significant risk factors be carefully taken into consideration before choosing to perform MIS XLIF/XLIF?

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Biomechanical Comparison of Single-Level Cervical Plate Fusion and Interbody Cage Fusion

Advances in Bioengineering ◽

10.1115/imece2002-32628 ◽

2002 ◽

Author(s):

Denis J. DiAngelo ◽

Amanda L. Thomas ◽

Kevin T. Foley

Keyword(s):

Cervical Spine ◽

Interbody Fusion ◽

Interbody Cage ◽

Biomechanical Stability ◽

Single Level ◽

Fusion Device ◽

Cervical Plate ◽

Anterior Cervical Plate ◽

Biomechanical Comparison ◽

Interbody Fusion Device

Anterior cervical graft fusion alone or supplemented with an anterior cervical plate instrumentation may be used to treat the diseased cervical spine. An anterior cervical plate is intended to restore the mechanical integrity of the operated spine and decrease graft complications. An alternative method to single-level graft fusion is to use an interbody fusion device. The objective of this study was to compare the biomechanical stability of a single-level graft-plated cervical construct with an interbody cage device.

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Minimally Invasive Lumbar Interbody Fusion in Patients Older Than 70 Years of Age: Analysis of Peri- and Postoperative Complications

Neurosurgery ◽

10.1227/neu.0b013e3182098bfa ◽

2011 ◽

Vol 68 (4) ◽

pp. 897-902 ◽

Cited By ~ 38

Author(s):

Isaac O. Karikari ◽

Peter M. Grossi ◽

Shahid M. Nimjee ◽

Carolyn Hardin ◽

Tiffany R. Hodges ◽

...

Keyword(s):

Postoperative Complications ◽

Minimally Invasive ◽

Interbody Fusion ◽

Lumbar Fusion ◽

Posterior Instrumentation ◽

The Elderly ◽

Major Complications ◽

Hardware Complications ◽

Lateral Interbody ◽

Graft Subsidence

Abstract BACKGROUND: The number of spine operations performed in the elderly population is rising. OBJECTIVE: To identify and describe perioperative and postoperative complications in patients 70 years and older who have undergone minimally invasive lumbar interbody spine fusion. METHODS: A retrospective analysis was performed on 66 consecutive patients aged 70 years or older who underwent a minimally invasive interbody lumbar fusion. Electronic medical records were analyzed for patient demographics, procedures, and perioperative and postoperative complications. RESULTS: Between 2000 and 2009, 66 patients with an average age of 74.9 years (range, 70-86 years) underwent 68 lumbar interbody fusions procedures. The mean follow-up was 14.7 months (range, 1.5-50 months). The minimally invasive approaches included 41 cases of extreme lateral interbody fusion and 27 minimally invasive transforaminal lumbar interbody fusions. We observed 5 major (7.4%) and 17 minor (25%) complications. The 5 major complications consisted of 4 cases of interbody graft subsidence and 1 adjacent level disease. There were no intraoperative medical complications. There were no myocardial infarctions, pulmonary embolisms, hardware complications requiring removal, wound infections, major visceral, vascular, neural injuries, or death in the study period. CONCLUSION: Minimally invasive interbody fusions can be performed in the elderly (ages 70 years and older) with an overall low rate of major complications. Graft subsidence in this population when not supplemented with posterior instrumentation is a concern. Age should not be a deterrent to performing complex minimally invasive interbody fusions in the elderly.

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