cancellous bone grafting

The advantage of cancellous bone transplantation is that it stimulates the osteogenesis, the crawling replacement process is fast, the anti-infective force is strong, and it can form fragments and fill any cracks between the bone ends. Therefore, it has a wide range of applications. Its disadvantage is that the texture is soft and the internal fixation is weak. Therefore, it is often necessary to use cortical bone graft or metal internal fixation in clinical practice. Generally, cancellous bone transplantation is mostly used for bone cavity filling or bone cavity filling, joint fusion, fracture nonunion, bone defect and the like after bone tumor or inflammation scraping. In addition, cancellous bone fragments can be transplanted in the treatment of fractures with poor blood supply (such as the lower third of the humerus fracture) to promote fracture healing. The tibia has more high-quality cancellous bone. When a large amount of cancellous bone is needed, it can be taken from the tibia; it can also be taken from the rib. When a small amount of cancellous bone is needed, it can be taken at the bone end adjacent to the diseased bone, but it contains more fat and has poor quality. Treatment of diseases: fracture non-union bone defect Indication 1. Bone defects caused by or after bone tumor resection. 2. Congenital sacral pseudoarthrosis, or pseudoarthrosis caused by nonunion of the fracture. 3. Various benign bone tumors or inflammatory lesions can be filled with cavities after scraping, and bone filling can be performed to restore the firmness of the bones. 4. Various internal and external fusion techniques, limb lengthening, osteotomy, and poor blood flow in the fracture for open reduction, bone graft can fill the defect, promote healing and strengthen fusion. 5. Congenital dislocation of the hip with acetabular capping or hip bone rotation. 6. Blood supply failure fractures, such as femoral neck intracapsular fractures, or ischemic osteonecrosis, such as adult femoral head necrosis, bone grafts that can be anastomosed to replace the sclerotic bone, increase local blood supply, and promote bone healing. Preoperative preparation 1. Prevention of wound infection is an important guarantee for the success of bone grafting. The anti-infective power of the graft bone is very weak. Once infected, the bone graft is soaked in the pus, necrosis will occur, and failure will occur. The precautionary measures are: the skin should be strictly prepared for the affected area and the donor area; the storage process of the stored bone must have strict sterility requirements; those with bone and soft tissue infection must be cured after 3 to 6 months of infection. Bone graft surgery, otherwise the surgery is easy to stimulate local latent bacteria, so that the infection recurs. Such patients should use antibiotics before surgery, and should use the anti-infective cancellous bone graft or the anastomotic bone graft. 2. The soft tissue around the bone area and the blood supply to the bone should be rich, and the growth force should be strong, so as to ensure the healing process of the bone graft. If the local skin and soft tissues have extensive scars, the blood supply will not be good, and the content after bone transplantation will increase, the skin will be difficult to suture, and infection will occur easily, forming a sinus. Therefore, the scar should be removed before surgery, and the flap should be transplanted to create conditions for the healing of the bone graft. 3. Many patients who need bone grafting have undergone multiple operations or long-term external fixation, resulting in muscle atrophy of the injured limb, decalcification of the bones, varying degrees of joint activity, poor blood circulation and low anti-infectiveness. The tissue growth ability is also poor. External fixation after an indispensable period of bone grafting will result in muscle atrophy and increased joint stiffness. Therefore, a period of functional exercise and physical therapy should be performed before surgery. For patients with non-displaced lower extremity fracture non-union or bone defect, functional exercise can be performed under the protection of stent or external fixation. 4. Preoperative x-ray film to understand the condition of the diseased bone, design the operation according to the condition (including the bone grafting part, the size of the bone graft and the bone grafting method). If the bone graft is to be anastomosed, the full length of the graft bone and the lateral x-ray film should be taken before surgery to select the site and length of the bone graft. 5. Before the bone graft of the anastomotic blood vessel, the ultrasonic artery should be used to detect the presence and blood flow of the main artery in the donor and recipient limbs in order to design the operation. Generally, the branches of the main arteries of the limbs are used for anastomosis, such as the deep femoral artery of the femoral artery, the inner and outer arteries of the circumflex femoral artery. If there are 2 main arteries in the receiving area, such as the ulnar artery, radial artery, anterior and posterior iliac artery, one of the main arteries may be used for anastomosis. The prerequisite must be that another major artery is confirmed by ultrasonic flowmeter or clinical examination. The blood supply is good. The veins in the recipient area are usually treated with superficial veins, such as the cephalic vein, the venous vein, the great crypt, the small saphenous vein and its branches. Therefore, the superficial vein of the recipient area should be examined for damage or inflammation before surgery. Recently used as a puncture, the superficial vein of the infusion cannot be used as a receiving vein. Surgical procedure Cancellous bone grafts are often used in conjunction with other procedures to fill bone cavity defects and promote healing. 1. Select a suitable incision according to the fracture site to reveal the site of non-union of the fracture, completely remove the scar tissue and the fractured-end hardening bone, and cut through the medullary cavity at both ends, and fix it with intramedullary nail, steel plate or cortical bone plate. . The bone defect area fills all the cracks and corners with cancellous bone fragments and gently tightens. Finally suture the periosteum and incision. 2. After the benign bone cyst or bone tumor is exposed, first drill a hole around the lesion, drill only one side of the cortical bone, each hole is arranged in a rectangular shape, and then use the bone knife to cut the bone between the holes, then you can take off a piece. Cortical bone, after the diseased tissue is scraped clean, the cancellous bone is filled. If the lesion is located in the weight-bearing area, an appropriate amount of cortical bone graft should be added. After gently tightening, suture by layer.