internal bolt fixation

The bolts are made at the tip of the dense screw with a nut (or a nut at both ends). After the fracture is restored, the screw is passed through the fracture block, and the nut is tightened outside the bone, and the fracture block is fixed by the clamping action, which is the bolt internal fixation. Treatment of diseases: fracture of the humeral shaft fracture Indication It is often used for T-shaped and Y-shaped fractures between the femoral condyle, humerus or humerus and some repetitive intra-articular comminuted fractures. Contraindications The patient is too old and should be filled with poor general condition. Preoperative preparation 1. Selection of bolts: Before the operation, the bolts with appropriate length and length and conforming to the specifications should be selected according to the x-ray film. The number of preparations should be more appropriate for selection. 2. Choice of drill bit: The drill bit is preferably made of stainless steel. Although it is sharp without tool steel, it is not easy to break. The diameter should be slightly smaller than the screw, generally the same as the diameter of the base of the thread (ie the bottom diameter of the thread). The diameter of the drill bit for the long bone end and the cancellous bone should be smaller, and the screw can firmly bite the bone and fully exert the fixation effect. Pressurized cortical bone screws only have a pressurizing effect when their threads are fixed to the contralateral cortical bone. Therefore, drill the sliding hole (drilling near the screw head), the diameter of the drill should be equal to the diameter of the thread, and the drill hole of the drilled hole (the hole of the contralateral cortical bone) should be smaller than the diameter of the thread. 3. Rotary chisel (screwdriver, screwdriver) requirements: Rotary chisel is divided into three types: ordinary straight, cross and hexagon, the latter two are used for compression screws. The width and thickness of the chisel head must be compatible with the screw groove of the screw (the width preferably exceeds the length of the groove), and the chisel head should be in close contact with the bottom of the groove. If a rotary chisel that does not meet the requirements is used, the screw groove is easily damaged during the screwing process. It is best to use a sleeve type rotary chisel that can fix the screw [Fig. 5], and it can advance and retreat stably and quickly without damaging the screw groove. 4. The tap is not automatically screwed out of the groove of the threaded passage at the end of the compression screw. Therefore, the sharp coring screw with a cutting edge must be used to drill the cortical bone and tap the thread. The diameter should match the diameter of the thread. Surgical procedure After the fracture is opened and closed, a drill is drilled through the center of the fracture block through the drill and through the contralateral cortical bone. Because the fixation is not dependent on the bite of the thread and the bone, but by the pinching action when the nut is tightened, the drill bit should be the same diameter as the bolt, so that the bolt can pass through the hole smoothly, and then the length is appropriate. Bolts, the length of which is just above the transverse diameter of the injured bone, it is better to screw the nut, and the bone surface cannot be exposed too long. Pass the nail through the hole until the outside of the contralateral cortex, make a small incision on the opposite skin, find the end of the bolt, screw the nut, and then screw the nut at the other end of the bolt. The tightness of the nut should be appropriate. If the joint surface is fractured, X-ray film should be taken during the operation. After observing the alignment, the layer is sutured. complication Hematoma compression Excessive hematoma after surgery not only creates growth conditions for the bacteria, but also may induce ischemic necrosis of the muscles and even form the compartmental syndrome. In this case, puncture and suction can not be resolved; can be entered by the original incision, clear blood clots and all necrotic tissue, or fasciotomy and decompression. 2. Infection Selective surgery, the infection rate is 2% in foreign statistics. The key is strict aseptic technique and non-invasive operation. Preventive antibiotics are not required. If you are not sure, add antibiotics for 3 to 5 days during the operation until the operation. Open fractures, antibiotics are necessary during and after surgery. Topical application of degradable sustained-release microsphere antibiotics is valuable for preventing infection. 3 to 5 days after surgery, local redness, swelling, heat, and pain should be considered as infection. It is necessary to open the wound in time, remove the necrotic tissue, and wash it repeatedly. The internal fixation stable plant does not have to be removed, taking antibiotic saline drip irrigation, recording the amount of wound in and out, bacterial culture, drug sensitivity test, timely replacement of effective antibiotics, lavage for 4 to 5 days, often can control the development of infection.