Indications 1. Bilateral displaced fractures of the condylar neck with reduced vertical height of the ascending branch and open jaw of the anterior teeth, with surgical repositioning and fixation on at least one side. 2.Dislocated fracture of the condylar neck with disturbed jaw relationship. 3. Overlapping displaced or dislocated fractures under the condylar neck. The above indications are mainly for fresh fractures in adults. Surgery is usually performed within 12 hours after the injury or 5-7 days after the fracture, at this stage, the soft tissue has not yet shown obvious reactive swelling, or the swelling has subsided. Surgical technique 1. Surgical maneuver For low condylar neck and subcondylar neck fractures, submaxillary and postmaxillary incisions are usually used. For high condylar neck fractures, an anterior auricular incision is usually used. For oblique or sagittal fractures of the condylar neck, a combined incision of both is required. At the mandibular angle, the mandibular marginal branch of the facial nerve is usually located at the level of the inferior border of the mandibular angle and is obliquely directed forward and downward, usually with the broad cervical muscle turned upward without injury. 2. Reveal the fracture by severing the chewing attachment and pushing up the chewing muscle to expose the mandibular angle. When disconnecting the chewing muscle attachment, the chewing muscle cavity should be sharply disconnected along the lower edge of the mandibular angle. If the chewing muscle fibers are severed bluntly, it is easy to cause postoperative mouth opening restriction. In order to fully reveal the condylar fracture and expand the operable field of view, the lower pole of the parotid gland can be freed and pushed upward, while the deep fascia of the parotid sheath at the posterior edge of the ascending branch can be incised to increase the liftable degree of soft tissue on the surface of the ascending branch. 3, fracture repositioning Before fracture repositioning, the mandibular ascending branch is tractored downward with a scarf clamp to extend the repositioning space, and then the fracture block is searched for and pulled outward, but the extra-parietal muscle attachment should be retained not to free the fracture block. The purpose of pulling out the fracture block is to identify the fracture line alignment, the shape of the fracture section, and to try anatomic repositioning to determine the fracture block return path and splint placement site. In the case of the anterior auricular incision, it can be found that the articular disc is displaced with the fracture block, and before resetting the fracture block, the articular disc needs to be reset and fixed with sutures. Note that simply resetting the fracture through the anterior auricular screen incision is easy to cause the fracture block to be free due to the small space for resetting, resulting in fracture healing equivalent to free bone grafting, and mild bone resorption may occur after surgery, but it will not affect the clinical results. 4, fracture fixation in accordance with the anatomical alignment of the fracture bone surface structure, choose the appropriate size of small joint plate, bend into shape, so that it fits with the bone surface. Then, re-draw the fracture block and fix the plate on the fracture block first, and then fix the ascending segment below the fracture line after anatomical repositioning. Note that at least two screws should be fixed to each bone segment, each of which is required to penetrate the contralateral cortical bone and hold on the bilateral cortical bone. Condylar neck fractures are generally fixed with a single splice splint placed on the posterior lateral edge of the condylar neck. Subcondylar fractures are fixed with two splints, one on the posterior lateral edge of the condylar neck and the other on the anterior condylar neck and lateral to the sigmoid notch for compensatory tension band fixation. Oblique section or sagittal fractures can be fixed directly with screws through the joint. 5. After anatomical repositioning and solid fixation, the condyle should be able to move freely with the mandible without any obstruction. The fetal relationship automatically returns to normal when the mandible is closed naturally. This examination must be done before closing the incision. Postoperatively, intermaxillary fixation is usually not required. Comment In the past, wire bolting was commonly used for internal fixation of condylar fractures. Regardless of the bolting method, it is difficult to obtain reliable fixation stability and must be combined with intermaxillary fixation for a period of time after surgery, and the fracture block is easily re-displaced, which seriously affects the effect of manual repositioning. Sturdy fixation with a small splint can effectively prevent postoperative re-displacement of the fracture fragment, avoid intermaxillary fixation, and allow early (usually 1 week postoperatively) functional jaw movement. A single plate for posterior external edge tension band fixation is sufficient to maintain the stability of the fracture fragment in condylar neck fractures. Subcondylar neck fractures usually require compensatory fixation at the anterior and sigmoid notches of the skeletal neck due to the distance of the extensor pterygoid muscle force point from the fracture line pivot point and the large force moment.