The set is intended for extraction of damaged bone screws, which cannot be removed with common procedures. It can also be used for removing broken drills and taps. In these cases you must take extra care to avoid damage to the instrument used by the hardened part of the removed damaged drill or tap.
Cutters, cylindrical cutters and extractors are equipped with hexagonal or AO terminal, which can be fixed in a chuck or AO terminal handle. We do not recommend using electric drills to extract the screws. Drills are provided with a cylindrical surface and are intended for connection to an electric drill.
All cutters and extractors are marked with size of the screw they are intended for. Screwdrivers match the size of the hexagon in the screw head. Diameter of the drill is always larger than the diameter of the screw shank.
Instructions for use
- broken screw head, the screw intersects both cortices
Orthopedic chisel allows for easier access to the broken screw and preparation of room for screw extraction in the proximal cortex. After you make enough space for the broken screw by pushing lightly and moving counterclockwise, screw on the extractor with left inner tapered thread. After fixing the broken screw in the extractor body, continue the counterclockwise movement of the extractor until the broken screw is unscrewed. It is necessary to use an extractor with the same marking for the respective bone screw. For example, to extract a broken bone screw HA 3.5, use the extractor labeled 3.5. In all cases, if a sufficient rest of the bone screw is available, you can use screw extraction forceps for extraction.
- broken bone screw, the screw is deep in the spongiosa
Prepare the access to rest of the broken nail using a cylindrical cutter. Cutter is equipped with a guide pin, which serves as a cutter stopper. Then use the cutter and insert it into the prepared hole. Use this cutter to mill over the proximal cortex to about 8 mm above the rest of the broken screw. After you take the cylindrical cutter out, screw the extractor with left inner tapered thread on the broken screw by pushing lightly and moving counterclockwise. After fixing the broken screw in the extractor body, continue the counterclockwise movement of the extractor until the broken screw is unscrewed. It is necessary to use instruments – cutters, cylindrical cutters and extractor – with the same marking for the respective bone screw. For example, to extract a broken cortical screw HA 3.5, use the cutter, cylindrical cutter and extractor labeled 3.5. In all cases, if a sufficient rest of the bone screw is available, you can use screw extraction forceps for extraction.
- deformed hexagon in the screw head
For extraction of bone screws with damaged inner hexagon in the screw head, you can use a special extractor. First use an excavator to clean the inner hexagon. Extractor is screwed into the damaged hexagon by turning to the left and by continuing anticlockwise movement the screw is extracted. For the respective size of hexagon you must use a special extractor with appropriate marking.
If there is a screw rotation, you can use a screw extractor to help the screw with light pulling.
- screw locked in the plate
If the screw cannot be removed from the plate either as usual or using one of the above methods, you can use a drill to drill the screw off. Drills are selected so as to allow the screw head to be drilled off the screw shank. In such a screw extraction, it is very important to drape the wound, to prevent chips from entering the patient‘s body. We recommend cooling drills with a disinfectant solution. This rinses the wound at the same time.
For example, for a screw of 3.5 mm diameter use a drill of 3.5 mm diameter.
Drill bits can be used to both steel and titanium implants.