Multilevel Oblique Lumbar Interbody Fusion in Degenerative Lumbar Disc Disease with Instability

Summary

This protocol presents the operative technique of multilevel Oblique Lumbar Interbody Fusion (OLIF) in a step-by-step manner, elaborating on the critical steps for achieving optimal outcomes.

Abstract

The surgical technique of L2- L5 Oblique Lumbar Interbody Fusion (OLIF), including the exposure of the surgical corridor, preparation of the disc space, and placement of the interbody cages, followed by pedicle screw fixation, is presented. To perform this technique, the patient is positioned in right lateral decubitus on a radiolucent table, and an oblique incision is made 3-5 cm anterior to the middle of the L3-L4 disc space. After dissecting the subcutaneous fat, the external oblique aponeurosis is cut along the line of the incision and the oblique muscles (external and internal), and the transversus abdominis muscles are split along the direction of the muscle fibers. Peritoneal fat is gently swept anteriorly until the psoas muscle is visualized. The psoas muscle is then retracted posteriorly to reveal the underlying disc space. A guide wire is inserted into the disc, followed by sequential dilators and placement of expandable retractors. After confirming the retractor position, annulotomy is performed, and the disc space is prepared using a combination of Cobb's elevator, curettes, and pituitary rongeurs, employing an orthogonal maneuver. Under the fluoroscopy guidance, serial trials are introduced, and an optimal-sized cage packed with bone graft substitutes is implanted into the disc space. The same steps are repeated at two adjacent levels (L2-L3, L4-L5), and the wound is closed in layers. The patient is turned into a prone position and pedicle screws are placed to complete the construct. The results of 30 patients who underwent this OLIF procedure were analyzed. The mean disc height was 7.47 ± 2.3 mm, which significantly increased to 10.9 ± 2.7 mm postoperatively (p < 0.0001). Similarly, the mean disc angle improved from 7.26° ± 6.2° to 9.81° ± 4.1° (p = 0.0065). At the final follow-up, both disc height and angle were maintained, along with satisfactory bony fusion, with no cases of pseudoarthrosis or implant failure.

Introduction

Degenerative disc disease is one of the most important causes of low back pain (LBP)¹. Advanced degeneration of the discs results in instability of the motion segment and stenosis, leading to persistent low back pain (LBP) and neurological symptoms. Early stages of the disease are usually treated conservatively. However, patients refractory to conservative management or those with neurological worsening need surgical intervention. Fusion surgery is a well-established treatment option for managing these symptoms in the lumbar spine, of which interbody fusion has been proven to be biomechanically superior to posterior fusion²

Protocol

This study was conducted in accordance with the ethical standards set forth in the 1964 Declaration of Helsinki and was approved by the Domain Specific Review Board, National Healthcare Group, Singapore.

1. Pre-operative considerations

1. Patient selection
   1. Assess the feasibility of the procedure using radiographs and MRI scans.
   2. Check for a high iliac crest (in the Anterior-Posterior radiograph) that could make performing OLIF at the L4-L5 level challenging, especially for surgeons in the early stages of their surgical practice.
   3. In patients with degenerative lumbar ....

Results

In the above-described patient, the overall surgical time for the first stage was 2 h, with an estimated blood loss of less than 100 mL (Table 1). The second stage of surgery was completed quickly, as robotic guidance facilitated the screw placement, making it a minimally invasive procedure. Supine and standing whole spine radiographs were taken, and the positions of the cage and screws were found to be satisfactory. Following the procedure, mobilization was initiated the next day. As it was a minimally .......

Discussion

OLIF surgery has become popular over the last decade in managing various lumbar spinal pathologies like instability, stenosis, and adult deformities⁹. It achieves indirect decompression of the spinal canal, provides a broader surface area for interbody fusion, widens the neural foramen, and corrects the spinal alignment¹⁰. All these surgical goals could be efficiently enabled using the minimally invasive (pre-psoas) approach with OLIF. Compared to other fusion techniques su.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Add-on arm with universal joint	Medtronic	10042177	The metal arm to attach the expandable retractors to the clamp
Bayoneted Penfield #4	Medtronic	9569650	To mobilize residual soft tissue from the disc for clear visualization of the annulus
C-arm fluroscopy	Siemens		To provide intra-operative radiographs during the surgical procedure
Cascadia Lateral 22*50*10 mm/ 8º	Stryker	6101-2225010LL8-G2	The OLIF interbody cage inserted in the disc space. 8º refers to the lordotic angle
Cascadia Lateral 22*50*8 mm/ 8º	Stryker	6101-2225008LL8-G2	The OLIF interbody cage inserted in the disc space. 8º refers to the lordotic angle
Cup curette, Size 5, Angled	Medtronic	3280017	To prepare the vertebral endplates
Dissection blade, 17 cm	Medtronic	10045377	Blade with long handle to cut the annulus of the disc
Elastic Adhesive cotton crepe 10 cm * 4.5 m	Convi	931 624	To strap the patient in position to the operating table, 10 cm * 4.5 m refers to the size
Foley catheter 14 Fr	Bard	123614CE	Silicone Elastomer coated catheter for bladder drainage during surgery, 14 Fr refers to the size
Guide wire, blunt, 450 mm	Medtronic	75700450	To puncture the annulus for level confirmation and placement of tubular dilators
Infuse Bone graft	Medtronic	P000058	Recombinant human bone morphogenic protein-2 that is placed in the interbody cage to aid in fusion
METRX, Dilator 10.6 mm	Medtronic	9561421	Sequential dilators to place the retractors, 10.6 refers to the size
METRX, Dilator 16 mm	Medtronic	9561422	Sequential dilators to place the retractors, 16 refers to the size
METRX, Dilator 20.8 mm	Medtronic	9561424	Sequential dilators to place the retractors, 20.8 refers to the size
METRX, Dilator 5.3 mm	Medtronic	9560420	Sequential dilators to place the retractors, 5.3 refers to the size
Monocryl plus, 3-0	Ethicon	MCP427H	Poliglecaprone antibacterial coated suture material, 3-0 refers to the size
NIM-Eclipse E4	Medtronic		For intra-operative neuromonitoring
Paddle shaver, 10 mm	Medtronic	2941610	To clear the end plates and to size the disc height
Paddle shaver, 12 mm	Medtronic	2941612	To clear the end plates and to size the disc height
Paddle shaver, 8 mm	Medtronic	2941608	To clear the end plates and to size the disc height
Pituitary rongeur, 6 * 14, straight	Medtronic	3280001	To remove the disc material during disc space preparation, 6*4 refers to size
Quick Connect Handle, Light source	Medtronic	10042129QL	To establish better illumination through the tubular retractors to the disc
Quick Connect to shaft clamp adapter	Medtronic	10042165	To attach the retractor blades to the retractor assembly
Rail Clamp	Medtronic	10041903ACL	To attach the metal arm to the operating table
Retractor assembly	Medtronic	10042138Q	To attach the rounded blades to the mounted operating arm
Round caudad blade, 11 cm	Medtronic	10045451	Distal rounded blade to accommodate the tubular dilators
Round cephalad blade, 11 cm	Medtronic	10045431	Proximal rounded blade to accommodate the tubular dilators
Slap hammer	Medtronic	9074002	To push the sizers and cage into the disc space
Straight Cobb, 10 mm	Medtronic	2942035	To detach the disc attachment and incise the contralateral annulus
Surgical blade, 10	Swann-Morton	201	To make the skin incision, 10 refers to size
Vicryl plus, 1	Ethicon	VCP486H	Polyglactin braided absorbable suture, antibacterial suture, 1 refers to the size
Vicryl, 2-0	Ethicon	J589H	Polyglactin undyed braided absorbable suture, 2-0 refers to the size