Arc-shaped intramedullary needle (Ender needle) internal fixation

The curved intramedullary needle, also known as the ender needle, is a kind of intramedullary needle. Its advantage is that it uses multiple intramedullary needles with certain elasticity and hardness to insert into the medullary cavity, reaching the femoral neck and fanning out. It can effectively control the activity of the fracture end. Especially for the elderly, because the affected limb can be active early, the bed time is shortened, thereby reducing systemic complications; the use of curved intramedullary needle internal fixation, short operation time, less blood loss, less trauma, incision away from the fracture site, and thus infected The risk is less than other internal fixation methods. The disadvantage is that multiple arcs are still insufficient for controlling the rotation of the fracture end, especially for patients with severe osteoporosis. The fixation is often not firm; at the same time, there are early and late complications, which cannot be ignored. Treatment of diseases: femoral fractures of the femoral subtrochanteric fracture Indication 1. femoral neck basal fracture, femoral trochanteric fracture, femoral subtrochanteric fracture; 2. Fracture of the femoral shaft, fracture of the lower part of the femur more than 5 cm above the adductor nodules. Contraindications 1. Unstable fracture of the femoral trochanter; 2. Severe osteoporosis, the curved needle is easily displaced in the medullary cavity; 3. For young and middle-aged adults, once the complications such as knee dysfunction or external rotation of the lower extremities occur, the consequences are serious and should be regarded as relative contraindications. Preoperative preparation 1. The curved intramedullary needle has three diameters of 3, 4, and 5 mm, and the length is between 33 and 39 cm, showing a curved natural curvature. The tip of the needle is blunt and round, and the tail of the needle is flat. It is matched with the driver, and the center hole of the needle is used for the needle. Injectors, extractors, benders, and bone hole expanders must be prepared before surgery. 2. The appropriate intramedullary nail should be selected according to the width of the stenosis of the medullary cavity (average adult 10.5mm) and the length of the femur before the operation, and several sets should be prepared for the operation. 3. Before the operation, according to the age and fracture displacement, skin traction or bone traction. Surgical procedure 1. Reset: The patient lies supine on the fracture complex. After the manipulation is reset, the affected limb is abducted by 30°, the internal rotation is 15-20°, and the feet are fixed on the foot support. The positive side x-ray film, or monitor with a TV x-ray machine, confirms that the reset is satisfactory, that is, strive to achieve anatomic reduction or close to anatomical reduction, and the lateral anteversion angle is not more than 10° (see femoral neck tri-spinning internal fixation) . 2. Incision, revealed: in the femoral condyle, equivalent to the upper edge of the humerus, longitudinal longitudinal incision, separation between the medial femoral and adductor muscles, the medial femoral muscle is pulled forward, revealing the lower end of the femur Cortical bone. On the periosteum about 3 cm above the adductor muscle nodules, there are upper knee movements and veins, which should be protected or ligated [Fig. 44-37 (1)]. 3. Chiseling the bone groove: 2 cm above the femoral condyle, at the junction of the inner wall of the femur and the posterior cortical bone, chisel a rectangular bone groove, about 1 × 2 cm3 size. Note that it should not be biased to prevent the tail from rubbing the quadriceps tendon, and it is not appropriate to hinder the femoral artery [Fig. 44-37 (2)]. 4. Needle insertion: according to the length of the femoral neck and the size of the neck dry angle displayed by the x-ray film, the proximal end of the selected curved needle is bent at 7-14 ° ~ 145 °, each difference of 2 ° ~ 3 °, The distal end of the needle is also slightly bent by about 5° at 2 to 3 cm. Insert the first curved needle with the arc inward and insert it in a rotating manner. When entering the unmyelinated section, there is a sense of resistance. In this fashion, the driver will hammer the needle into it and have a substantial sense when hammering in. When the 2nd and 3rd needles are inserted into the medullary cavity, each needle should rotate 12°15° from the above needle, and the front end of the needle should be inclined 10°15° to make the 3 needles enter the femoral neck. The fan is fanned out to prevent the fracture from rotating and prevent the needle from being incarcerated in the medullary cavity. The tip of the needle is about 0.5cm below the surface of the femoral head joint, and the length of the needle tail is 0.5cm. The flat part of the needle tail should be closely attached to the cortical bone. The number of needles is suitable for embedding the medullary cavity, usually 2 to 4 [Fig. 44-37 (3)]. 5. Myelin: X-ray film or TV x-ray machine monitoring believes that after the fracture is restored and the position of the needle is satisfactory, it is sutured by layer. complication 1. The needle fracture of the needle is caused by too small bone groove. In the case of a split fracture, the needle can be changed to the external femoral condyle, or other internal fixation can be used. Patients with severe cleft palate fractures can be fixed with wire loops. 2. The needle is displaced proximally or slides out to the distal end: mostly due to osteoporosis in elderly patients, the needle fails to completely block the medullary cavity, and/or the weight is premature. The treatment method should be to delay the weight or to remove the needle that has slipped out too long. 3. Knee joint pain: more due to the needle position before the needle or the tail of the needle slips out of the stimulus. In addition to the operation should pay attention to the operation of the essentials, you need to delay the load. For severe pain, it is advisable to re-surgery to advance or advance the needle. 4. External extremity external rotation, intramedullary stenosis, limb shortening deformity: mostly seen in unstable fractures, poor reduction, insufficient number of fixed needles or depth, etc., so should pay attention to the choice of indications.