Lag screw technique | 合法醫療器材資訊網

Thecancellousbonescrewandthecorticalscrewthroughaglidinghole.Intheproximaltibiamostoftencancellousbonescrewsareusedduetotheabsenceof​ ...

Lag-screw technique Lag screws / the lag technique compresses the fracture fragments together. There are two screw types by which to achieve this. The cancellous bone screw and the cortical screw through a gliding hole. In the proximal tibia most often cancellous bone screws are used due to the absence of real cortical bone. Nevertheless, there are some indications for cortical lag screws.

1) Cancellous bone screw Cancellous bone screws have threads only on the terminal end of the screw. Therefore, when inserted across a fracture, the threads of the tip of the screw engages in the cancellous bone of the metaphyseal area, causing compression of the fracture fragments upon tightening. Because of the weakness of the cortical bone in this area washers are used to prevent sinking of the screw head into the bone.

2) Cortical screw through gliding holeThe application of cortical screws inv...