1.1 Data and methods 1.1 General data Eighty-six patients with distal femoral fractures in our department from October 2011 to December 2012 were randomly divided into the LISS group and the DCS group. There were 46 cases in the LISS group, 31 males and 15 females; age 20 to 53 years old, average 33.8 years old. 40 cases in the DCS group, 28 males and 12 females; age 21 to 57 years old, average 35.2 years old, the differences between the two groups in general data such as age and gender were not statistically significant (P>0.05) and comparable. 1.2 Methods 1.2.1 DCS group In the patient, an incision was made on the lateral side of the distal femur to fully expose the fracture end, and when there was a bare intertrochanteric fracture, the fracture was firstly repositioned under direct vision and temporarily fixed with 2 kerf pins. The bare screw is nailed in the upper 3/4 of the longest diameter of the external bare. The guide pin is placed 2 cm from the articular surface. After screwing in the bare screw, a DCS plate is placed. The DCS plate can be pre-bent as needed so that the plate can be tightened against the lateral femoral cortex, and care is taken to maintain a valgus angle of about 5° in the knee joint. A compression screw is used to lock the plate to the bare screw and fix it to the distal femoral bare. The postoperative compression bandage is applied without external fixation. 1.2.2 In the LISS group, a lateral curvilinear incision was made in the knee joint, and the length of the incision was usually 6 cm. In the case of intra-articular fractures, care was taken to extend the incision so that the proximal tibial articular surface could be exposed, and the intra-articular fracture block was repositioned anatomically, and after repositioning, it was fixed with a kerf pin, and in some patients, screws were added; for dry medullary end fractures, closed repositioning was used. The steel plate is inserted in a prograde manner between the anterolateral calf muscle group and the lateral tibial periosteum, and the length is best controlled so that 4-5 screws can be driven into the distal end of the fracture. An auxiliary incision is made at the proximal end of the fracture, about 5 cm in length, and after confirming that the plate is in tight contact with the femur, the drill sleeve and locking bolt are removed and the penetrator is inserted through the drill sleeve. Tighten the drill sleeve through the external screw and replace the puncturer with the fixation bolt. After screwing the fixation bolts into the LISS splice plate, the fixation frame is closed. Four to five locking nails are placed on each of the proximal and distal ends. No external fixation was required postoperatively. The patient can start functional muscle contraction and knee flexion and extension exercises in 3 d after surgery, and can move around without weight-bearing after 2-4 weeks after surgery with the help of double crutches, or on the CPM machine. To fracture healing. 1.3 Judgment of efficacy Excellent: knee extension to 15°, flexion to 130°, normal activity; Good: knee extension to 30°, flexion to 120°, normal activity, or slight pain and impairment; OK: knee extension to 40°, flexion to 90°~110°, painful activity and moderate walking impairment; Poor: no improvement in symptoms, large activity impairment and severe pain. 1.4 Statistical methods SPSS17.0 statistical software was used, and P<0.05 indicated that the difference was significant. 2, Results Patients were followed up, the follow-up time was 12 months, the excellent rate of LISS group was 91.3% than the excellent rate of DCS group was 75.0%, P<0.05 difference was statistically significant. Distal femur fracture is relatively common and complex in clinical practice. It is often associated with severe soft tissue injuries, bone defects, and injuries to the knee joint and quadriceps extensor apparatus, and the treatment outcome is often unsatisfactory. Treatment should follow the principles of anatomic repositioning, strong fixation, and early and moderate rehabilitation to try to improve the outcome. Patients with distal femoral fractures require surgical repositioning first, and during fixation, the fracture site is more mobile, and after surgery, the patient's recovery exercises and daily activities tend to loosen the fixation, so the effect of conventional fixation is often unstable [1]. The distal femur fracture is a proximal joint or involves the articular surface, and because it is located at the dry scale end, it has a thin bone cortex, a large medullary cavity, and mostly cancellous bone. The traditional method is fixation using DCS, which relies on power compression screws, plates and compression locking nails, etc. This fixation method has a long incision, is more traumatic, has relatively extensive stripping of soft tissues, and can have an effect on the blood supply to the fracture end. Especially for those with medial cortical defects, care should be taken to supplement with autogenous bone graft. This method has certain defects in the line of fixation force, and any bending and twisting force at both ends of the fracture can easily loosen the screw or fracture the plate resulting in deformity.