Matrix 5.5 Deformity and Matrix MIS

Roger Härtl, Jean Ouellet, Andreas Korge, Robert McGuire, Paul Heini
The Matrix 5.5 deformity spine system provides biomechanically sound results for complex posterior pathological challenges. 

Matrix MIS allows for minimally invasive rod and screw insertion during thoracolumbar pedicle fixation. Pedicle trauma is minimized by using muscle-sparing approaches to expose patient anatomy.

The Matrix spine system is a universal set of instruments and implants designed to accommodate both open and minimally invasive surgical (MIS) approaches to deformity, as well as degenerative and trauma indications. The system is composed of pedicle screws, pre-assembled polyaxial pedicle screws, monoaxial screws, hooks, locking caps, transconnectors, rods, and polyaxial head implants.

Matrix 5.5 Deformity

The Matrix polyaxial and monoaxial pedicle screw features dual-core, double-lead threads, threaded T25 StarDrive recesses and 50° of angulation with rod reduction features located at the top of the screw head. The matrix 5.5 deformity polyaxial heads can be removed and replaced intra-operatively without removing the bone screw. The 5.5 mm diameter rod material options include titanium, Ti-6Al-7Nb, and CoCr with multiple-length curved pre-contoured and hex-end versions.

Locking caps are square-thread design with a saddle on the underside to prevent skiving during rod reduction. The saddle is designed to pilot the locking cap to the screw head to minimize cross threading. The snap-on transconnector is a pre-assembled implant and features an arched telescoping body. The jaws of the transconnector have the ability to swivel and are spring loaded for tension application until final tightening.

Matrix MIS

This system uses cannulated pedicle screws attached to screw-mounted tissue retractors. This combination allows pedicle screw insertion and rod introduction with minimal tissue disruption. The system is applicable to single and multi-level procedures requiring posterior instrumentation.

Matrix MIS uses the same locking cap and pedicle screw technology as matrix 5.5 deformity and matrix degen.

The 5.5 minimally invasive rods are pre-lordosed with 100mm or 200mm bend radius. The 100mm bend rods are available in 35-85 mm lengths in
5mm increments. The 200mm bend rods are available in 60-130 mm lengths in 5mm increments.

Unique to Matrix MIS are cannulated pedicle preparation instruments, screw-mounted tissue retractors and a rod introduction instrument.

Cases provided by Roger Hrtl, New York, USA


PLIF Technique with Matrix MIS

Presentation of the minimally invasive technique for placing interbody cages. Indications and technical tips are presented.

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