12.1 Introduction

Vertebral plates are another type of instrumentation used for spinal fixation. Historically, lateral lumbar interbody fusions (LLIFs) were performed as stand-alone procedures. ¹ However, stand-alone interbody cages exhibited questionable stability due to limited resistance in vertebral motion. ^{2 3 4} As such, supplemental fixation has been frequently utilized. However, posterior fixation in this setting requires patient repositioning and may increase the risk of complications and may increase morbidity. ¹ Lateral plates can be used in the setting of minimally invasive lateral approaches with the advantage of utilizing the same surgical approach as the interbody cage. ¹ This avoids the need for patient repositioning and reduces the risk of additional procedures. These instruments are often composed of a titanium plate with multiple screw slots for fixation to the vertebral body. Occasionally, the plate and screws are integrated with the interbody cage (Chapter 11 Lateral Interbody Cages) or VBR Device (Chapter 13 Vertebral Body Replacement Devices) in order to facilitate hardware placement. ⁵ Surgical indications are presented in ▶ Table 12.1.

12.2 Outcomes

Screw–plate constructs have exhibited successful outcomes in reducing vertebral motion following interbody fusions. ⁶ Lateral plates have been demonstrated to increase lumbar rigidity in flexion and extension. ^{6 , 7} Lateral plates have also been noted to substantially reduce motion in lateral bending and axial rotation. ⁸ Compared to bilateral pedicle screws (Chapter 3), screw–plate constructs have exhibited similar efficacy in terms of fixation and reducing vertebral motion. Furthermore, the utilization of lateral plates for fixation has been suggested to reduce patient morbidity. ^{6 , 9} Previous studies have demonstrated shorter operative times, reduced blood loss, and decreased time under fluoroscopy. ⁶ Plate instrumentation may also avoid many of the complications associated with posterior fixation, such as iatrogenic neurologic injury. ⁶

12.3 Lateral Fixation Device Systems

Table 12.2 Globus Medical InterContinental® LLIF Plate-Spacer System

Design
Composition Titanium and polyetheretherketone (PEEK)		Design feature Plate and spacer assembled intraoperatively to minimize disruption to patient anatomy Two bone screws secure the plate-spacer and compressively load the graft chamber to promote fusion
Modular aspects and variations
Plate-Spacer specifications				Screw Specifications
Width 20 mm	Lengths 40–65 mm (5-mm increments)	Lordotic angle 0°, 6°, 20°, 25°	Heights 0°, 6°: 8–17 mm 20°, 25°: 11–21 mm	Diameter 5.5 mm	Lengths 30–55 mm (5-mm increments)
Procedures
MIS LLIF, MIS corpectomy
Supplemental fixation system
Globus Medical TransContinental® M Spacer System, InterContinental® Plate System, Minimal Access Retractor System

Table 12.3 Globus Medical PLYMOUTH® Thoracolumbar Plate System

Design
Composition Titanium	Design feature 2- and 4-screw plate designs with simple locking set screw to allow visual confirmation
Modular aspects and variations
Screw diameter 5.5 and 6.5 mm	Screw lengths 22–57 mm	Plate lengths 15–24 mm
Procedures
MIS LLIF, MIS corpectomy
Radiographs unavailable
Supplemental fixation system
Globus Medical TransContinental® M Spacer System, CALIBER®-L Interbody Systems

Table 12.4 K2 M CAYMAN® Minimally Invasive Plate System

Design
Composition Titanium	Design feature TiFix locking technology enhances plate fixation and promotes stability
Modular aspects and variations
Screw diameters 5 and 5.5 mm	Screw lengths 24–60 mm (4-mm increments)	Plate lengths 8–18 mm (2-mm increments)
Procedures
MIS LLIF, MIS corpectomy
Supplemental fixation system
K2 M RAVINE® Lateral Access System, ALEUTIAN® Lateral Interbody System

Table 12.5 NuVasive SpheRx® II Anterior System

Design
Composition Titanium	Design feature Multiple staple sizes with 10-mm-long fixation spikes designed to fit unpredictable patient anatomy
Modular aspects and variations
Polyaxial screw specifications		Fixed-screw specifications
Diameter 5.5, 6.5, 7.5 mm	Lengths 25–50 mm (5-mm increments)	Diameter 5.5, 6.5, 7.5 mm	Lengths 25–60 mm (5-mm increments)
Procedures
MIS LLIF, MIS corpectomy
Radiographs unavailable
Supplemental fixation system
NuVasive MaXcess® Access System, XLIF® Expandable VBR System

Table 12.6 NuVasive Traverse® Anterior Plate System

Design
Composition Titanium	Design feature Compression plate utilizes Spiralock® unidirectional locking thread to minimize cross-threading Fixed plate utilizes canted coil locking mechanism
Modular aspects and variations
Screw diameters 5.5 and 6.5 mm	Screw lengths 25–65 mm (5-mm increments)	Compression plate lengths 45–80 mm (5-mm increments), 85, 95, 105 mm	Fixed plate sizes 15–70 (5-mm increments), 80, 90 mm
Procedures
MIS LLIF and MIS corpectomy
Supplemental fixation system
MaXcess® Access System, XLIF® Expandable VBR System

Table 12.7 RTI Surgical Lat-Fuse® Lateral Plate System

Design
Composition Titanium	Design feature Utilizes expanding sphere locking mechanism that allows for visual confirmation
Modular aspects and variations
Screw diameter 5.5 and 6.5 mm	Screw lengths 30 mm, 40–70 mm (5-mm increments)	Plate lengths 14–28 mm (2-mm increments)
Procedures
MIS LLIF, MIS corpectomy
Radiographs unavailable

Table 12.8 Zimmer Biomet Timberline® MPF Lateral Modular Plate Fixation System

Design
Composition Titanium and polyetheretherketone (PEEK)		Design feature 1-, 2-, and 4-screw plate designs with single-step lock plate to prevent screw back
Modular aspects and variations
Plate-spacer specifications				Screw specifications
Widths 18 and 22 mm	Lengths 45–60 mm (5-mm increments)	Lordotic angle 0°, 8°	Heights 8–14 mm (2-mm increments)	Diameter 5.5 and 6 mm	Lengths 30–60 mm (5-mm increments)
Procedures
MIS LLIF, MIS corpectomy
Supplemental fixation system
Zimmer Biomet Supplemental Fixation System