total hip replacement

The artificial total hip joint consists of an artificial acetabulum and an artificial femoral head. In the past, both used metal, and practice proved that there are many complications, and it is not used now. At present, acetabular acetabulum made of ultra-high molecular polyethylene and artificial femoral head made of low-strength modulus metal are used at home and abroad. There are many types and designs of artificial total hip joints, mainly the diameter of the femoral head and the design of the acetabular surface fixed with the bone. The thicker acetabulum, the total hip with a relatively small diameter of the artificial femoral head, has small head rubbing force, stable artificial sputum, and small local reaction. In addition to the complications of artificial femoral head replacement, there are complications of artificial total hip arthroplasty, such as loosening of the artificial acetabulum, dislocation and local reaction caused by abrasion of the ultra-high molecular polyethylene surface in the weight-bearing area. Treatment of diseases: hip osteoarthritis congenital dislocation of the hip Indication 1. Those who have the following indications when they are over 50 years of age may have artificial total hip replacement. Those who are under 50 should be cautious. The acetabular destruction is severe or has obvious degeneration, severe pain, and limited joint activity, which seriously affects life and work. 2. Rheumatoid arthritis, joint stiffness, stable lesions, but good knee joint activity. 3. Aseptic necrosis of the femoral head and old femoral neck fracture with femoral head necrosis, severe deformation, collapse and secondary hip osteoarthritis. 4. Artificial femoral head replacement, artificial total hip replacement, hip fusion failure. Contraindications 1. Old and frail, with serious heart and lung disease, can not tolerate the operator. 2. Severe diabetes patients. 3. Hip septic arthritis or osteomyelitis. 4. Hip joint tuberculosis. Preoperative preparation 1. Comprehensive physical examination, understanding the heart, lung, liver and kidney function, and appropriate treatment to adapt to surgery. 2. Patients with femoral neck fractures should be treated with preoperative skin traction or tibial tuberosity. The upward displacement of the distal end of the fracture and the contraction of the muscles around the hip should be corrected to reduce intraoperative and reduce postoperative complications. 3. Antibiotics are routinely given 1 to 3 days before surgery, and contraindications are given to the affected area to prevent infection. 4. Regular skin preparation for 3 days; night enema before surgery, fasting 12 hours before surgery. 5. Select artificial femoral heads of similar size and place x-ray films on the same plane as the hips. According to this, select and prepare suitable artificial femoral heads and spare ones for each of the larger and smaller ones. 6. Special equipment for medullary cavity, artificial femoral head hammer, femoral head extractor, femoral head grasper, bone cement, etc. Surgical procedure 1. Position: depending on the choice of different incisions. When using the posterior lateral incision, the patient is lying on the side and the affected side is on the upper side. Lateral or anterior lateral incision, the patient is supine, and the affected side is raised. 2. Incision and exposure: The choice of incision should be based on hip deformity, soft tissue contracture, and the surgeon's experience and habits. The selection principle should facilitate soft tissue release, adequate joint exposure, and prosthesis placement. The posterior lateral, anterior lateral incision and exposure pathway are used clinically (see the hip joint exposure pathway). The previous lateral incision is described as an example. 3. Resection of the joint capsule, dislocation of the hip joint: After revealing the hip joint capsule, the adhesion outside the joint capsule is separated, and the front, upper and lower, full up to the acetabulum, down to the trochanter base, and the joint capsule and synovium are removed. . The hip joint is externally rotated and adducted to dislocate the femoral head, and the joint capsule and synovium remaining behind the hip are removed. If the hip joint is stiff, the femoral neck should be first cut, and then the femoral head should be removed with the acetabulum. After dislocation, the soft tissue contracture should be carefully examined in combination with preoperative malformation and loosened until the hips move in all directions without obstruction. 4. Excision of the femoral head, trimming the femoral neck, and expanding the medullary cavity: see artificial femoral head replacement. Use dry gauze to tighten the medullary cavity to stop bleeding, and do not put the prosthesis temporarily, so as not to affect the treatment of the acetabulum. 5. Clean the acetabulum: There are sciatic nerves, femoral movements, veins and femoral nerves in the soft tissue around the hip joint. To avoid injury, apply a pointed or toothed hook, and the tines hook on the bone outside the acetabular rim. External tilting can open the surrounding soft tissue, which avoids slippage and satisfactorily reveals the acetabulum. Excision of the labrum, round ligament, all intraorbital soft tissue and cartilage surface. If the bone is very hard, you can use a round chisel to remove a layer of subchondral bone. If there are too many callus on the acetabular rim, it should be properly removed. If the head is fused, it should be first sculpted between the head and the head. The acetabular chisel cuts the head and forms a false twist. Use the acetabular size suitable for artificial acetabulos to deepen the acetabulum until it can fully accommodate the artificial acetabulum, and then expand it properly. Because the artificial acetabular rim can not exceed 0.5cm of the original iliac crest, the filling bone must be left. The space of cement. When using the acetabulum, attention should be paid to the direction, that is, the camber is 40° to 50°, and the flash is 10° to 15° for the placement of the artificial acetabulum. At the same time, note that the bone at the top of the outer edge of the acetabulum can not be removed too much, in order to maintain the stability of the artificial acetabulum after surgery, and the inner wall of the sputum is thin, so be careful not to penetrate when sputum, especially for patients with osteoporosis. Then, a bone hole of 0.8 cm in diameter and 1 cm deep is scraped on the sputum, shame, and isch bone to fill the bone cement to strengthen the cementing strength of the bone cement. Finally, rinse with saline to remove all blood, clots and bone chips, use dry gauze to compress, completely stop bleeding, if necessary, use electrocoagulation, hydrogen peroxide or hemostatic fibers to stop bleeding, and then keep the dry gauze pressed until the bone cement is applied. 6. Place the artificial acetabulum: The surgeon changes the gloves. When the assistant mixes the bone cement to the non-stick gloves, the bone cement is evenly filled into the dry acetabulum with fingers, and the three strengthening holes must also be filled. Then put the artificial acetabulum on the cement on the acetabular bed. Generally, the cap is placed obliquely against the lower back edge of the iliac crest, and then quickly pressed upwards and upwards with the acetabular adjustment presser. Tightly and evenly attached to the trampoline, and using the two arms of the positioner, adjust and maintain the artificial acetabulum at an angle of 45° and 10° to 15° forward according to the position. At the same time, the cement spilled around the artificial acetabulum is scraped off, but the bone cement between the bone and the skull cap cannot be damaged. The pressurizing pressurizer can be removed only after the pressurization is maintained until the cement is cured. If the position of the cap is moved after the bone cement begins to harden, it is bound to pull the bone cement out of the bone or the cap and loosen it, which must be avoided. If the cap is found to be improperly placed, the cap and bone cement should be removed decisively before the bone cement has completely cured. After rinsing, repeat the above steps and squeeze the artificial acetabulum with a pressurizer. If there is a bloody liquid overflowing from the bone cement and the bone or the sputum cap, it means that the fixation will not be good, and it should be taken out and repositioned. If it is firmly fixed, it can check and remove the epiphysis, excess bone cement and bone fragments scattered in the soft tissue. 7. Artificial femoral head replacement: see artificial femoral head replacement. 8. Sutures were rinsed with 1:1000 benzalkonium solution, soaked for 5 minutes, and the wound was rinsed with physiological saline. Thoroughly stop bleeding, put a vacuum suction tube near the artificial joint, and poke a small incision through the outer skin of the incision, then suture the wound layer by layer, and pressurize the wound. complication 1. Cryptic pneumonia: An elderly patient with a subcondylar fracture of the femoral head is one of the surgical indications for total hip replacement. Postoperative patients have bed rest due to dysfunction, and many patients refuse to change their position frequently due to fear of the wound drainage tube and severe pain. The elderly have a weakened state of the respiratory function and acute stress. The body's resistance is reduced, and it is easy to have hypostatic pneumonia. In severe cases, it will lead to respiratory failure, which is one of the common causes of death after complications in the elderly. 2. Muscle atrophy and joint dysfunction: For patients with femoral neck fracture, skin traction or bone traction should be given before surgery to achieve the purpose of braking, partial reduction and pain relief. Fear of pain, can not reach a wide range of activities in a short period of time, muscles and joints do not get active for a long time, muscle atrophy, joint stiffness, resulting in slower recovery in the future, or poor recovery effect, affecting postoperative expectations effect. 3. Artificial joint infection: Joint infection is a catastrophic complication for patients with total hip replacement. Prevention of postoperative infection is the key to the success of total hip arthroplasty. There are many factors that cause wound infection, such as loose dressing or shedding of wound dressings, exposed wounds; excretions contaminate wounds; patients with low resistance, especially those with diabetes, poor blood sugar control, are high risk factors for infection. 4. Deep venous thrombosis of the lower extremity: Thromboembolic disease is a common complication after orthopedic surgery. It is a serious hazard. The three major factors of venous thrombosis are hypercoagulability of blood, stagnant blood flow and damage of blood vessel wall. Due to the fracture of the lower limbs, the patient is braked and the activity is limited, which makes the blood flow slow. In addition, the trauma and surgical factors of the fracture itself will damage the blood vessel wall, and the damage of the blood vessel wall will initiate the blood coagulation mechanism, so that the blood is in a hypercoagulable state. Foreign data shows that the incidence of DVT after artificial hip and knee joint replacement. It is 50%~70%. 5. Artificial joint dislocation: According to the literature, the incidence of prosthesis dislocation after THR is 0.2%~6.2%, most of which occurs in the first month after operation. The anterior approach easily causes anterior dislocation, and the posterior approach easily causes posterior dislocation. The lateral approach dislocation rate is very low, and the posterior approach requires the hip external rotation muscle group to be cut during surgery. The dislocation rate is twice as high as the lateral approach, but it has the advantages of convenient field exposure and less bleeding. I like to use it clinically. All patients in our department use the posterior approach, so the main purpose of nursing is to guide the patient to prevent posterior dislocation.