Lateral-PLIF for Lumbar Spinal Arthrodesis: A Detailed Step-By-Step Surgical Technique

Summary

Lateral-PLIF is an advanced posterior lumbar interbody fusion technique allowing safer cage insertion with minimal neural manipulation. This article outlines the step-by-step procedure, highlighting the benefits of the bilateral approach, optimal cage orientation, high fusion rates, and low complication risks, offering a promising alternative to traditional PLIF.

Abstract

Posterior lumbar interbody fusion (PLIF) is widely recognized as an effective surgical approach for treating degenerative lumbar spine conditions. To address challenges associated with the classical PLIF technique, such as the need for extensive neural retraction and the associated risk of dural tears, we developed a novel variant, the Lateral-PLIF, which optimizes cage placement to enhance outcomes and minimize risks. This article offers a detailed, step-by-step explanation of the procedure, highlighting its advantages in the operative field. Here we present a case of a posterior interbody fusion performed for a lumbar degenerative disease. The technique involves bilateral cage placement through the transition zone, between the central canal and intervertebral foramen, just above the lateral recess. This entry point is strategically chosen as it is safer for respecting the surrounding nervous structures, avoiding manipulation of the foraminal root, while reducing medial dural retraction and providing a better cage orientation. Finally, the technique keeps the advantages of the bilateral approach: direct bilateral decompression, high-quality discectomy, and endplates cleaning performed from each side, progressive distraction achieved from the disc space alternating right/left, and opportunity for massive bone grafting. Lateral-PLIF is a safe and effective surgical technique for lumbar interbody fusion. Its high fusion rate, improved functional outcomes, and low complication rates make it a promising alternative to traditional PLIF. This step-by-step article serves as a practical guide for surgeons, promoting the broader adoption and further validation of this technique in comparative studies.

Introduction

Lateral Posterior Lumbar Interbody Fusion (Lateral-PLIF), described by Capo et al., is an innovative surgical technique designed to combine the benefits of both posterior lumbar interbody fusion (PLIF) and transforaminal lumbar interbody fusion (TLIF), with the aim of overcoming the limitations associated with these approaches¹. The technique seeks to achieve stable arthrodesis of the lumbar spine while minimizing complications such as nerve root injury, muscle damage, and dural tears, which are prevalent in traditional PLIF and TLIF procedures^2,3,4,5. By utilizing a lateral approach to the intervertebral foramen, lateral-PLIF allows for direct posterior and foraminal decompression, ensuring optimal spinal alignment and load-bearing capacity. This is especially important for patients suffering from degenerative conditions, spondylolisthesis, and recurrent disk herniation, as it offers a safer alternative for decompression while providing a biomechanically stable fusion environment.

The development of Lateral-PLIF was motivated by the need to reduce the high complication rates observed in more traditional posterior techniques, particularly PLIF, which is known for its higher incidence of neurological and dural complications^6,7,8. Studies have shown that while PLIF provides good decompression and fusion rates, its risks often prompt surgeons to explore safer alternatives, including TLIF and lateral approaches like XLIF and OLIF^7,9. Lateral-PLIF combines the advantages of these alternatives by minimizing the need for extensive nerve root manipulation, preserving muscle tissue, and facilitating easier access to the lumbar spine through a posterior approach. The evidence supports the safety and efficacy of Lateral-PLIF, with studies suggesting improved patient outcomes in terms of neurological preservation and fusion success when compared to conventional techniques¹. This method is particularly suitable for patients with complex spinal pathologies where traditional methods may pose higher risks. As the technique gains traction, it offers a promising solution for surgeons looking to balance effective decompression with reduced complications, offering a viable option in the broader landscape of spinal surgery.

This article aims to describe the Lateral-PLIF technique step by step, in a practical manner for spinal surgeons, promoting its wider adoption and use in order to validate its effectiveness and safety in comparative studies. Here, a step-by-step procedure is presented for a single-level L4-L5 Lateral-PLIF addressing a L4-L5 type III (the degenerative type, according to the Wiltse classification¹⁰), grade I spondylolisthesis with significant canal stenosis.

Protocol

The surgical procedure was performed in accordance with its intended use and standard clinical practice. All steps adhered to established medical guidelines and institutional protocols of the Pierre Wertheimer Neurological Hospital, Hospices Civils de Lyon, France. No deviations from approved techniques were undertaken.

1. Pre-operative preparation

1. Administer general anesthesia to the patient. Then, place the patient in a prone position on the Jackson table with a chest bolster and hip pads.
2. Display the radiological images of the patient and your surgical plan in the operating room.
3. Perform the standard preoperative checklist.
4. Identify the target level using fluoroscopy and mark the incision site on the patient's back.
5. Prepare and drape the patient's back using the standard sterile fashion.

2. Surgical procedure

1. Make a standard posterior midline skin incision centered on the operative level.
2. Incise the lumbar fascia and carefully expose the posterior bony elements subperiosteally, including the lamina of the two adjacent vertebrae, posterior facets, and pedicular entry zones.
3. Perform a subtotal facetectomy by bilaterally resecting the inferior facet of the upper vertebra using an osteotome. Partially remove the superior facet of the lower vertebra, flattening it to facilitate pedicle screw insertion.
4. Insert multiaxial pedicle screws at the appropriate levels and confirm correct placement using biplanar fluoroscopy or CT-guided navigation.
5. Apply an interlaminar distractor at the base of the spinous processes to improve exposure and enlarge the working space.
6. Introduce the sterile-draped microscope into the surgical field, using magnification and illumination appropriate for the specific surgical step.
   NOTE: Typically, low magnification is used for the initial surgical steps.
7. Resect the midline ligamentous structures while keeping the adjacent spinous processes intact.
8. Remove the tip and medial part of the superior facet to expose the proximal intervertebral foramen, located at the transition zone between the central and lateral canal, just above the lateral recess.
9. When necessary, use a Kerrison rongeur to further open the lateral recess and decompress the passing nerve root. If additional central decompression is required, perform partial laminectomy and flavectomy.
10. Facilitate exposure of the underlying disc space by removing the lateral ligamentum flavum and underlying fatty tissue, preserving the fatty tissue surrounding the nerve root.
11. Control epidural bleeding as needed using bipolar coagulation and/or hemostatic agents.
12. Once hemostasis is achieved, expose the disc between the dural sac medially and the foraminal root laterally, with minimal or no retraction of neurological structures.
    NOTE: Increase the magnification and align the microscope with the axis of the disc to allow for its proper exposure, incision, and removal.
13. Create a rectangular window in the annulus using a scalpel blade, positioning it in the transitional zone between the lateral part of the central canal and the medial part of the intervertebral foramen.
14. Use a nerve root retractor to protect the dural sac, applying only limited retraction.
15. Use specialized straight and angled osteotomes, pituitary rongeurs, rasps, and curettes to elevate and remove disc material.
16. Apply intervertebral distraction on one side, starting at 6-7 mm and gradually increasing to 11-12 mm, allowing safe and controlled discectomy on the contralateral side.
17. Perform distraction progressively, alternating sides by 1 mm increments, until satisfactory disc height restoration is achieved according to preoperative planning.
18. Complete endplate preparation from both sides of the dural sac with removal of the cartilaginous layer until the bony endplate of the adjacent cranial and caudal vertebrae is clearly exposed.
19. Measure the disc space for an appropriately sized interbody cage.
    NOTE: The most commonly used cages have a height of 11-12 mm, a lordosis angle of 8-10°, and a length of 20-25 mm.
20. Pack the anterior disc space and both cages with bone graft, using either local bone or bone substitutes depending on the clinical situation.
    NOTE: To enhance bone fusion, a 1.0 cc pack of synthetic bioactive bone substitute is routinely added to the morselized autologous bone used to fill each cage.
21. Insert the two cages into the interbody space and advance them using a straight impactor.
22. Contour the rods in slight lordosis and place them inside the screw heads.
23. Apply segmental compression to optimize restoration of local lordosis.
24. Protect the dura with a collagen sponge and place additional bone graft along the rods, with some bone chopsticks allograft positioned in the bridge against the two adjacent decorticated lamina.
25. Confirm the correct placement of cages, pedicle screws, and rods using planar fluoroscopy or an intraoperative CT scan.
26. Close the incision in a standard fashion.

3. Post-surgical care

1. Let the patient start walking on postoperative day 1 and perform standing X-rays before discharge.
2. On postoperative day 1, switch to oral pain medications for better comfort and mobility.
3. Discharge the patient on postoperative day 3 with follow-up in 3 months.

Results

According to findings by Capo et al., the lateral-PLIF technique has demonstrated remarkable effectiveness, not only in alleviating pain and enhancing functional recovery but also in significantly improving neurological deficits¹. The procedure boasts an impressively low complication rate both in the short and long term, coupled with an outstanding bone fusion success rate.

In the cohort of 104 patients analyzed by Capo et al., a striking 96.1% presented with lower back...

Discussion

The Lateral-PLIF technique introduces a novel approach to posterior lumbar interbody fusion (PLIF) by modifying the standard procedure to achieve satisfying decompression with minor nervous structures retraction, easier cage placement, and a higher fusion rate¹.

A key feature of this technique is the bilateral approach, which enables simultaneous interbody distraction and simplified cage insertion for optimal stability and alignment. By incorporating spinous process rem...

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Glassbone	Noraker	https://noraker.com/en/products/glassbone-putty/	Synthetic and bioactive bone substitute
Icotec	Global S	https://www.icotec-medical.com/en-us/implants/plif-cage/	Intervertebral carbon-titanium coated cages
Legacy	Medtronic	https://gahpl.com/pdf/thoracolumber/Legacy.pdf	Screws + rods
Osteopur	OST	https://www.ost-laboratoires.com/wp-content/uploads/2024/02/Catalogue-Osteopure-2022-SANS-PRIX.pdf	Bone allograft
PASS	Medicrea	https://thespinemarketgroup.com/wp-content/uploads/2021/09/PASS-LP-Degen-SGT.Medicrea.pdf	Screws + rods
Tivato 700	Zeiss	https://www.zeiss.com/meditec/en/products/surgical-microscopes/tivato-700.html#LanguageSwitchOverlayCloseButton	Microscope
VITOM 3D	KARL STORZ	https://www.karlstorz.com/us/en/category.htm?cat=1000161026	Endoscope
Ziehm Vision FD	Ziehm Imaging	https://www.ziehm.com/en/products/ziehm-vision-fd/	X-ray fluoroscope