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Neuro
MatrixNeuro Ultra Low Profile (ULP) The MatrixNeuro system was developed in 2008 to offer a complete system for use in craniotomies, cranial trauma repair, and reconstruction of the craniofacial skeleton. Although it provided the lowest plate/screw profile in implants of its kind at that time, patients continued to require even less profile. Many patients find that plates can still be felt or visible as lumps under their skin. This is increasingly important, as there are a large number of procedures that include the frontal area, which, according to Prof Christian Matula, Chair of the Neuro Trauma Reconstruction Expert Group (NTREG) “is an area that the patient looks at every day in the mirror and can make them feel unhappy”. Additionally, the unconscious rubbing of plates can lead to other skin issues. Fig 1 MatrixNeuro ULP implants.
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Fig 2a–b Screw recess modified for more plate-screw contact (better seating) and lower profile.
Fig 3 Chamfered edges on the ULP implants (green).
Fig 4 Selection of implant shapes.
The new MatrixNeuro Ultra Low Profile (ULP) system (Fig 1) decreases the plate-screw profile even further while providing comparable construct stiffness and strength to the plates in the existing MatrixNeuro system. The plate thickness is only 0.28 mm (MatrixNeuro standard plates are 0.40 mm). Also, the screw recess was improved to achieve a better seating of the screw, which has led to a plate-screw profile of 0.44 mm, a reduction of another 10% compared with the existing system. And instead of having a rectangular edge, the plates are chamfered to achieve almost no palpability under the skin. A wide range of plates is available based on the most frequently used MatrixNeuro standard plates, ie, Burr Hole Covers ranging from 12–24 mm with one additional version for shunt or drainage, as well as straight plates with center space in 2-hole and 4-hole versions. The system is completed with an X Plate, a square and a rectangular Frame Plate, a Double Y Plate, and a Strut Plate. The new MatrixNeuro ULP system is fully compatible with the existing MatrixNeuro system so that no new or specific instruments are needed, and the same surgical techniques are used. Furthermore, all implants are fixated with the already existing self-drilling screws from the MatrixNeuro system, which have a unique thread design for rapid screw starting and significantly lower insertion torque. The screws start with bone contact almost instantaneously providing a fast closure of bone flaps and rapid fixation of cranial fractures.