Biomet Anterior Cervical Plate System
A PLATE AND SCREW FOR CERVICAL FIXATION
Anterior Cervical Plating is a standard orthopedic surgical procedure for stabilizing and fusing adjacent vertebral bodies. During the procedure, surgeons remove the affected intervertebral disc, fill the space with a bone graft, and cover it with a secured cervical plate. The cervical plate keeps the bone graft in place and provides stability between the vertebrae above and below the graft. To accommodate variables in anatomy, bone screws used to secure the plate are available at fixed and variable angles. One of the biggest challenges of this procedure is preventing the bone screws from backing out. Currently, two categories of plate designs are available that have an anti-backout mechanism. The first involves a one-step method where the locking mechanism captures the screw to the plate upon insertion into the bone. The second is a multi-step method where after securing the screw in the vertebrae, the surgeon must perform a secondary action activating the locking mechanism. While there is equal surgical preference between the two categories, the current IP market is very crowded. Biomet approached Synectic to design a novel multi-step cervical plate that will compete in an overcrowded IP landscape.
First, our medical device design engineers analyzed the current IP market for design opportunities. Our industrial designers used this information to generate six novel concepts that would not compete with current IP. These concepts were down-selected based on cost, ease of production, and maximum screw angulation. The selected design involves a spring wedge clip consisting of two pivoting clips that lock at different attitudes and can accommodate a differential between the trajectory angle of the bone screws. To evaluate the ability of the locking concept to resist screw bending, our engineers created a breadboard prototype. Based on the breadboard results, we refined the design to minimize bulk and streamline production. Once we finalized the plate design, our engineers designed variable and fixed screws that would work with the locking clip mechanism. Conjointly, they developed a tool for compressing the clips and one for locking the plate, using “off the shelf” components to decrease production time and cost. Finally, we produced a production-level prototype of the complete system.