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NFlex Stabilization System The NFlex stabilization system is a semi-rigid rod for posterior lumbar stabilization. The rods are designed to be used with either the pangea or click'X pedicle screw systems. NFlex enables dynamic stabilization of the posterior lumbar spine. Principles of dynamic stabilization include decreased stiffness compared to traditional rigid stabilization and increased load sharing with surrounding anatomical structures. Dynamic constructs provide less resistance to spinal loading and motion. The NFlex rod motion allows more load transmission to the anterior column than rigid fusion. The main goal of the NFlex surgical technique is to implant the rod so that the patient can utilize the full range of motion and load-sharing capabilities of the device. The NFlex stabilization system features precurved and straight rods for mono- and multisegmental posterior stabilization. The rods feature dynamic and solid ends for transitional rigidity. A titanium ring allows for sliding and toggling coupled motion. The polymer sleeve bumper allows for controlled titanium ring motion in flexion, extension, lateral bending, and axial rotation at the dynamic level. Finally, a titanium alloy tapered core provides transitional rigidity.
Fig 1 NFlex construct.
Lengths of the NFlex rods are 40–85 mm in 5 mm increments. The set also includes a 150 mm straight rod. Four trial implants are provided, corresponding to the various rod lengths from 40–85 mm. In addition, a 150 mm long bending template is included in the set to establish the contour of the 150 mm straight NFlex rod.
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Fig 2a–c The NFlex rod motion allows more load transmission to the anterior column than rigid fusion.