The Midline Fixation Procedure is designed to achieve more cortical bone purchase in the medial to lateral trajectory when compared to traditional pedicle screws. It takes no more time and clarifies the exposure of the lumbar transverse processes and intertransverse region. MidLine procedure minimize disruption to the nerves, muscles and tissue surrounding the surgery site. Today, we introduce 8 Midline Cortical Systems:
1.- TiLock Cortical Spinal System | Genesys Spine
Posterior spine fusion with screw fixation is a common and reliable method of instrumentation of the spine for a variety of spine pathologies when the ultimate aim of surgery is the fixation of the spine to allow bony fusion. The mainstay of this kind of surgery has been the use of pedicle screw fixation. The trajectory of pedicle screws aims to transverse the pedicle down its anatomical axis, with a screw specifically designed for fixation in cancellous bone. More recently, Santoni et al., in 2009 proposed using an alternative trajectory, a cortical bone based fixation technique, which utilizes a different path down the pedicle with the aim of maximizing the contact between screw and cortical bone.
Posterior lumbar spine fusion using the cortical based trajectory has advantages over traditional pedicle screw techniques including reduced dissection and tissue trauma, increased biomechanical stability in both high and low quality bone and is thereby a valid alternative to traditional techniques.¹
The Genesys Spine TiLock® Cortical Spinal System is designed to provide surgeons and their patients with a robust, anatomy-conserving alternative to traditional pedicular fixation.
• Low-profile tulip head
• Over-the-wire insertion for a simple, less-invasive approach
• Reduced tulip head that allows for efficient screw placement with nominal bony removal
• Corticocancellous thread pattern for maximum fixation in bone
• Tapered cortical self-tapping thread for initial placement
2.-CENTERLINE | Life Spine
The CENTERLINE Thoracolumbar Spinal System is designed to perform a MidLine procedure minimizing disruption to the nerves, muscles and tissue surrounding the surgery site. The low profile Cobalt Chrome tulip head and cortical cancellous screw thread design conserves space without compromising strength.
- Low profile Cobalt Chrome tulip head and 4.75mm rods minimize space requirement without compromising strength
- Cortical cancellous thread design maximizes screw purchase
- Midline approach conserves anatomy surrounding the surgical site
- Pre-Timed locking cap assembly reduces chance of cross threading
3.-Reform® MC | Precision Spine
The Reform® MC Posterior Lumbar Fusion System utilizes a minimally disruptive approach designed to reduce muscle retraction laterally past the facet joint. This approach requires a smaller incision while maintaining direct visualization and access to the disc space. Reform MC’s medial to lateral trajectory, combined with a cortical cancellous screw thread design, achieves greater cortical bone purchase. Reform MC features a modular screw design to maximize visualization and a low profile, cobalt chrome, tulip to conserve space without compromising strength.
- Modular System enables intraoperative flexibility
- Stepped Proximal Diameter optimizes bone purchase during final seating
- Low Profile Tulip decreases potential of anatomical interference
- Reform MC Retractor provides optimal access while minimizing muscle disruption
- Retractor Blades increase procedure flexibility
4.-CorticaLINK Cortical Screws | LinkSPINE
Designed for a rigid Midline Approach
- Cortical thread form – maximizes fixation for the dense bone trajectory
- Ti6Al-4V Screws, with 5.0mm diameter, and lengths from 25mm – 45mm
- 5.0mm curved rods in CoCr or Ti6Al-4V rods with lengths between 25mm and 200mm
- Biased angle screw tulips designed to simplify rod placement when
adjacent screws are placed in close proximity to one another, when the adjacent screw entry locations significantly differ from a medial-lateral perspective, and/or when adjacent screw angulations are markedly divergent.
5.-JANUS™ Midline Fixation Screw | Orthofix
As an addition to the Firebird® Spinal Fixation System, the JANUS® Midline Fixation Screw from Orthofix provides surgeons with the option of a midline approach.
The JANUS Midline Fixation Screw is designed to achieve more cortical bone purchase in the medial to lateral trajectory when compared to traditional pedicle screws. With its modular screw design, maximized visualization is possible when working in a smaller midline incision or minimally invasive surgical approach.
- Increased cortical bone purchase
- 12% increase in overall thread density*
- 43% increase in cortical region thread density*
- Self-drilling, self-tapping screws allow for fewer surgical steps
- Threads extend to the tip for controlled insertion and tactile feedback
- Compatible with Firebird® Spinal Fixation System and Phoenix® Minimally Invasive Spinal Fixation System
- JANUS Midline Fixation Screw is available in both non-cannulated and cannulated versions
- Available in the following sizes to accommodate a variety of anatomies:
- Diameters: 4.5, 5.5, 6.5, 7.5mm
- Lengths: 25, 30, 35, 40, 45, 50, 55, 60, 65mm
*compared to Firebird 5.5mm x 30mm length pedicle screw
6.-Mariner Midline | Seaspine
The SeaSpine® Mariner® Midline system expands the versatility of the Mariner fixation platform to enable a less invasive midline cortical procedure. This system combines procedure specific implants and instrumentation with the strength of Mariner modular technology to address a wide range of spinal pathologies.
- Unique implant thread form designed to optimize biomechanical performance
- Thread-on modular technology for in situ head deployment and optimum strength
- Multiple tulip options for polyaxial and motion-limiting configurations
- Anatomically designed constrained rod for zero overhang and precise rod approximation
- Extensive implant diameter and length options for patient-specific anatomical fit
- Accompanied with true midline access retractor and intelligently streamlined tray layout for more efficient procedural workflow
7.-Xia CT (Cortical Trajectory) | Stryker
The LITe LIF (less invasive technologies lumbar interbody fusion) procedure using the Xia CT (Cortical Trajectory) implants and instruments facilitates a midline approach to help achieve decompression and fixation. You can use the Xia CT implants and instruments to place screws in a cortical trajectory in the lumbar spine. When used together with Xia CT, the LITe Midline Retractor offers you optimized visualization of the surgical site without the need for headlamps.
- Modular taps provide a low profile post for distraction without the need for in situ screw head assembly
- The low profile screw head (12.1 mm) allows you to directly visualize the anatomy and optimize your screw placement in a LITe LIF procedure
- The universal distractor has multiple adapter options to accommodate a variety of distraction methodologies
8.-MySpine MC | Medacta
MySpine MC is a 3D printed patient matched solution in the midline cortical approach. Posterior lumbar fusion is driven in a minimally invasive, muscle sparing way, allowing for shorter operating times and a substantial reduction of both radiation exposure and costs.
The goal of MySpine MC is to combine an excellent fusion rate with greater predictability of the clinical outcomes.
Minimally disruptive, medialized access with paramedial muscle retraction promotes:
- Enhanced muscle preservation
- Reduced blood loss
- Faster patient recovery
- Supradjacent facet preservation
9.- CREO MCS® Stabilization System | Globus Medical
CREO MCS® is a stabilization system that provides cortical screw fixation through a minimally invasive approach.
- Minimally Invasive Approach
- Allows a midline surgical approach for minimal tissue and muscle retraction, sparing the multifidus and other surrounding anatomy.
- Cortical Fixation
- Dual Outer Diameter and cortical thread pitch are designed for anatomical fit and fixation.
- Maximized Modularity
- Allows screw heads to be attached in situ following decompression, for visualization in the surgical field.