PMC4369897_01
AP and lateral radiographs of lower lumber spine showing the anterolateral locking plate at L4-5 (Synthes 4.5 mm anterolateral spinal locking plate, with 5.5 mm titanium locking screws, West Chester, Pennsylvania, United States).
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fig1
He underwent extensive debridement of the L4/5 disc and paraspinal tissues, as well as an L4/5 anterior discectomy and fusion with femoral allograft secured with a Synthes Spine titanium anterolateral locking plate (Figure 1).
Photograph of the plate after removal, demonstrating the cold welding of the screw head to the plate (top screw: this was the one release with a peripheral burr cut, top right hole of plate), the trajectory of the burr holes made to release the plate (middle two screws, requiring burr cuts from the center of the plate to each hole, bottom two holes), and the cold weld of the reverse threaded screw driver to the screw head (bottom screw, top left hole).
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fig2
Once the plate threads were released the screw was easily removed (Figure 2).
Image of the three reverse threaded screw drivers used. The top driver was successful in removing the screw but cold-welded to the interface. The bottom two drivers broke distally when used unsuccessfully on the remaining screws.
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fig3
We were successful in removing one screw with a reverse threaded screw driver, but we subsequently broke a total of 3 reverse threaded drivers attempting to remove the final three screws (Figure 3).