MatrixRIB Fixation System
William Long, Mario Gasparri, Stephan Schulz-Drost, Arthur Martella, Edward Black
The need to improve rib fracture care has been recognized for many years. To this end a number of surgeons have been using operative approaches including plates, intramedullary devices, vertical bridging, wire, sutures, and struts to repair the chest wall. Next to the attempt to achieve improvements in pain control, the goal with for this system has been reducing the duration of mechanical ventilation, ICU time, as well as the risk for chest wall deformities.
Although the majority of cases with fractured ribs can adequately be treated non-surgically, the remaining number particularly severe chest wall trauma cases can be a cause of morbidity and mortality, especially in the presence of a flail chest where paradoxical inward movement of the flail segment in inspiration is found. About 10% of chest wall trauma cases result in a flail chest. Flail chest injuries, defined as fracture of at least three consecutive ribs in at least two locations each, are associated with a mortality rate of up to 36%.1
Implants and screws
The MatrixRIB pre-contoured plates are available in sets of four (four left plates and four right plates, see Fig 2a) with designs that correspond to a specific rib or rib pair (Fig 2b). The plates, which cover fractures in all ribs suitable for plating, were designed to accommodate anatomic similarities between specific ribs.
The MatrixRIB Fixation System is used with 2.9 mm self-tapping, locking cortex screws ranging from 6 to 14 mm in length (in increments of 2 mm). These screws are designed to be used with both the Synthes rib plates and intramedullary rib splints. The screws are made of titanium alloy (Ti-6Al- 7Nb). A 6 mm non-locking screw is also available to temporarily secure the plate during insertion of the locking screws. This non-locking screw is intended to be removed and replaced with a locking screw prior to soft-tissue closure.
The fixation of plates and screws can be done in the standard fashion, drilling of holes should be done most cautiously to avoid the risk of pneumothorax.
In addition to the plates, the MatrixRIB Fixation System includes intramedullary rib splints for fixation and stabilization of rib fractures especially on the posterior side in a minimally-invasive fashion. The rib splints have a rectangular cross-section, provide bicortical screw fixation, and are available in three widths: Small (3 mm), Medium (4 mm), and Large (5 mm).
For their implementation, specifically designed drill guides with hook as well as templates to prepare the canal are available.
Chest Wall Deformity Reconstruction System
In May 2015, the MatrixRIB long straight plates 24- and 30-hole were launched as part of the Chest Wall Deformity Reconstruction System (Fig 4a). Shortly after we have witnessed the launch of the new sternal plates (Fig 4b & 4c) which complete the system and provide users with a comprehensive and varied portfolio for chest reconstruction.
New components added to the MatrixRIB Fixation System
The new self-drilling locking screws are 2.7 mm in diameter and available in 1 mm length increments from 8 mm to 20 mm. Self-drilling nonlocking screws are 2.7 mm in diameter and available in 10 mm and 12 mm lengths (Fig 5a). These are provided as alternatives to the existing MatrixRIB Self-Tapping locking and nonlocking screws. The pointed, cutting tip of the MatrixRIB Self-Drilling Screws enables surgeons to insert the screws without drilling a pilot hole. The new MatrixRIB Self-Drilling Screws are designed to lock the MatrixRIB plates 1.5 mm to create the same secure construct as the MatrixRIB Self-Tapping Screws. New screw guides are provided to ensure coaxial alignment of the self-drilling screws to the MatrixRIB plates 1.5 mm and MatrixRIB Splints, reducing the variability in screw alignment and orientation during insertion and ensuring construct locking strength (Fig 5b and Fig 5c). The Plate Screw Guide engages with the contours of the existing plate profile (Fig 5d). This Plate Screw Guide has also cut-outs on both ends that enable the surgeon to visually align to the adjacent screw holes. The MatrixRIB Self-Drilling Screws can be used in both the open and Minimally Invasive Plate Osteosynthesis (MIPO) approaches. If a suture is needed during the MIPO procedure, the guide has a through hole where a suture could be used as a tether (Fig 5e). The MatrixRIB Self-Drilling Screws are not meant to be used with the thick MatrixRIB plates 2.8 mm or in the 90° approach.
 Ciraulo DL, Elliott D, Mitchell KA, Rodriguez A. Flail chest as a marker for significant injuries. J Am Coll Surg. 1994 May;178(5):466-70.
Mohr M, Abrams E, Engel C, et al. Geometry of human ribs pertinent to orthopedic chestwall reconstruction. J Biomech 2007; 40: 1310-1317.
The specially developed instrumentation includes three plate holding forceps to assist the positioning of the plates during drilling and screw insertion procedures. These forceps are designed to be inserted from the superior aspect of the rib and hold the plate to the rib. The large version spans across multiple ribs to minimize the number of incisions in the intercostal space.
Case image provided by W Long, Portland, OR
The new universal caliper is designed for easy readability, durability, and compact size. In comparison with the currently available flat caliper this device also offers improved handling capabilities yet is easier to clean. The calibrated markings are etched in black on an off-white arm extension, which has a square shape and is etched on all four sides. The extensions arm is made of radel (polyphenylsulfone (PPSU)) for better durability. It is intended for various areas of thoracic surgery, ie, with the sternal fixation system and the matrix rib system.
The treatment of chest wall deformity and pectus deformity using the MatrixRIB System
Minimal Invasive Rib Stabilization
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