Patellar fracture

　　Fractures are caused by direct and indirect violence. Direct violence is often due to the direct impact of external force on the patella, causing patellar fracture, such as collisions, kicks, etc., and the fracture is mostly comminuted. Indirect violence is often due to the sudden contraction and traction of the quadriceps muscle, such as when suddenly slipping, the knee joint is semi-flexed, the quadriceps muscle contracts abruptly, pulls the patella upwards, and the patellar ligament fixes the lower part of the patella, resulting in patellar fracture, which is mostly transverse fracture.

　　First, early complications

　　1. Traumatic shock:Severe femoral shaft fractures can cause internal bleeding of up to 500 to 1000 milliliters or more, and the pain stimulus after trauma may cause shock early. The principle of treatment is to fix the fracture early to reduce internal bleeding, expand blood volume and relieve pain, and actively treat shock.

　　2. Crush syndrome:Severe crush injuries can lead to fractures of the femoral shaft, and attention should be paid to the occurrence of crush syndrome. The principle of treatment is to prevent acute renal failure and hyperkalemia, to give early and rapid fluid replacement, alkalinize the urine, diuretics, relieve renal vascular spasm, and even perform fasciotomy decompression.

　　3. Vascular and nerve injury:Fractures of the lower segment of the femoral shaft, when the fracture fragments displace posteriorly, can injure the popliteal vein and sciatic nerve. The principle of treatment is to properly fix the fracture and avoid repeated movement of the affected limb.

　　4. Fat embolism syndrome:The medullary cavity of the femoral shaft contains a large amount of yellow marrow with a high fat content, which can cause fat embolism syndrome after injury. The principle of treatment is to strictly immobilize the patient and avoid random movement.

　　Second, late complications

　　1. Malunion of fractures:It is divided into angular deformity, shortening deformity, and rotational deformity. The principle of treatment is that mild shortening in children can be corrected spontaneously, mild shortening in adults can be compensated by垫高鞋跟, and shortening of more than 2.5 centimeters or rotational deformity all require surgical correction.

　　2. Non-union of fractures:The principle of treatment is to prevent infection, effectively fix and prevent premature activity.

　　3. Stiffness of the knee joint:Long-term traction fixation of the knee joint or surgery and fracture trauma affecting the knee joint can cause knee contracture and stiffness. The principle of treatment is to perform early knee flexion and extension activities, manual massage, or surgical release, etc.

　　4. Delayed healing or non-union of patellar fractures:

　　The incidence of non-union of patellar fractures is low, ranging from 2.4% to 4.8%. Treatment: For patients with no symptoms or mild symptoms, non-surgical treatment is adopted, although the fracture does not heal, the function of the affected knee is still good. For patients with obvious symptoms, surgical treatment is adopted, and an open reduction and tension band wire fixation is performed according to the specific situation, with partial or total patellar resection. Most patients show significant improvement in function after surgery.

　　5. Refracture of the patella:The incidence is 1% to 5%. Due to the incomplete recovery of the patellar ligament's control over knee stability in the short term after bone healing, coupled with insufficient strength of the patellar internal fixation, insufficient time for knee mobilization, when the patient exercises or walks, with insufficient protection, the affected knee suddenly gives way, the quadriceps muscle contracts forcibly, causing a refracture. If the bone fragments are separated greatly after the fracture, and the parapatellar fascia tissue is torn, it is still necessary to perform an open reduction and internal fixation.

　　The age of occurrence of patellar fracture is generally between 20 to 50 years old, with more males than females, about 2:1. After patellar fracture, swelling and blood accumulation in the knee joint often occur, with skin abrasion and subcutaneous hematoma visible in front of the patella, with marked tenderness. Displaced fractures can be felt at the fracture gap. Passive movement of the knee joint causes severe pain, and sometimes bone grinding sensation can be felt. Patellar fractures are usually classified according to the location of the fracture, the shape after the fracture, and the degree of displacement.

　　1. Non-displaced patellar fracture

　　(1) Non-displaced transverse fracture.

　　(2) Non-displaced comminuted fracture.

　　2. Displaced patellar fracture

　　(1) Transverse fracture at the middle third of the patella.

　　(2) Transverse fracture at the superior or inferior pole of the patella.

　　(3) Displaced comminuted fracture.

　　(4) Longitudinal fracture.

　　(5) Osteochondral fracture.

　　Transverse fractures are the most common, accounting for 50% to 80% of all patellar fractures, most occurring in the middle third or lower third; comminuted fractures account for 30% to 35%; longitudinal fractures and osteochondral fractures are the least common, accounting for 12% to 17%. Longitudinal fractures are often caused by direct violence acting on one side of the patellar joint surface. Osteochondral fractures usually occur in adolescents and are often accompanied by traumatic patellar dislocation or subluxation.

　　1. Ankle pump exercise:Patient's foot and ankle movement - actively, slowly, and as widely as possible, which is of great significance for promoting circulation, reducing swelling, and preventing deep vein thrombosis.

　　After the early pain after the injury is slightly reduced, it is necessary to start practicing the isometric contraction of the quadriceps muscle.At least 100 times per hour to prevent the quadriceps from adhesion, atrophy, and weak extension, laying a foundation for walking on the ground. If there are no contraindications, the patella should be moved left and right at any time to prevent adhesion between the patella and the articular surface, and to practice the movement of the ankle and foot joints.

　　After the soft tissue repair of the knee joint is healed, start to practice lifting the leg.After the suture is removed from the wound, if there is no local swelling or effusion, the patient can walk with crutches while supporting the double crutches with a cast, without bearing weight on the affected limb.

　　After 4 to 6 weeks, the external fixation can be removed and the exercise of knee flexion and extension can begin.After a long time of immobilization, the knee joints have varying degrees of functional exercise limitations, therefore, various forms and methods of exercise should be adopted, such as combining active and passive exercises, exercises on the bed and under the bed, exercises with and without equipment, etc. When the external fixation is just removed, it is difficult to actively flex the knee, so more passive initiation forms can be adopted, such as having others help to flex the knee; after a certain degree of mobility is achieved, active movement can be changed. Patients can actively extend and flex their knee joints while lying in bed, or squat down beside the bed or door frame to practice the extension and flexion function of the knee joint. The sandbag pressing method is also very simple, that is, let the patient sit on the edge of the bed, extend the affected limb over the edge of the bed, place a sandbag of about 3kg on the ankle, for 15 minutes each time, twice or three times a day, but attention should be paid to the passive activity force to be moderate to avoid causing new injuries, and the intensity of exercise should be individualized to avoid fatigue.

　　5, If there is no need for external fixation with plaster splint after the operation, then the joint activity function can be practiced early.

　　When taking X-ray films, the lateral and oblique positions of the knee joint should be used instead of the anterior and posterior positions. The lateral position is most useful for determining transverse fractures and fragment separation, but it cannot understand whether there are longitudinal fractures or comminuted fractures. The oblique position can conventionally adopt external rotation 450 degrees to avoid overlapping with the femoral condyle; it can show the whole picture and is more conducive to diagnosing the longitudinal fractures on the lateral side. If there is a suspicion of injury on the medial side, then internal rotation 450 degrees can be taken. If there is a high clinical suspicion of patellar fracture and X-ray films of all positions and sides have not shown, then a patellar section X-ray film can be taken again.

　　1, Early stage (1-2 weeks):The injured part has blood stasis and swelling, meridians and collaterals are blocked, and the treatment during this period focuses on promoting blood circulation and removing blood stasis, and promoting Qi flow and dispersing. Traditional Chinese medicine believes that "if blood stasis does not go away, bones cannot grow" and "if blood stasis goes away, new bones will grow". It can be seen that removing swelling and blood stasis is the primary task for fracture healing. The principle of diet coordination is to keep it light, such as vegetables, eggs, soy products, fruits, fish soup, lean meat, etc.

　　2, Middle stage (2-4 weeks):Most of the ecchymosis has been absorbed, and the treatment during this period focuses on harmonizing the camp to relieve pain, removing blood stasis and promoting new growth, and joining bones and tendons. In terms of diet, it should be transformed from light to appropriate high-nutrition supplementation to meet the needs of callus growth. It can add bone soup, Tianqi braised chicken, animal liver and other foods to the initial diet to provide more vitamin A, D, calcium, and protein.

　　3, Late stage (more than 5 weeks):After 5 weeks of injury, the ecchymosis of the fractured part has basically been absorbed, and the growth of callus has begun, which is the late stage of fracture. The treatment should be supplemented, through the nourishment of the liver and kidney, Qi and blood, to promote the formation of a more solid callus, and to relax the tendons and collaterals, so that the adjacent joints of the fractured part can move freely and flexibly, and recover the past function. In terms of diet, the taboos can be lifted, and the diet can be supplemented with old hen soup, pork bone soup, lamb bone soup, deer tendons soup, braised water fish, etc. Those who can drink can choose Du Zhong Sui Sui Wine, Jixueteng Wine, Hu Gu Mu Gua Wine, etc.

　　4, Avoid sour, spicy, dry and hot foods in the early stage, and do not give greasy and nourishing foods too early:Such as bone soup, fat chicken, braised water fish, etc., otherwise, blood stasis will accumulate and be difficult to disperse, which will inevitably delay the course of the disease, slow down the growth of callus, and affect the recovery of joint function in the future.

　　5, Do not use shape to complement shape:Some people believe that eating more meat bones after a fracture can promote early healing. In fact, this is not the case. Modern medicine has proven through multiple practices that eating more meat bones after a fracture cannot only promote early healing but may also delay the healing time of the fracture. The reason for this is that the regeneration of bone after injury mainly relies on the function of the periosteum and bone marrow, and the periosteum and bone marrow can only better exert their functions under the condition of increasing bone collagen. The main components of meat bones are phosphorus and calcium. If a large amount of them is consumed after a fracture, it will promote the increase of inorganic components in the bone, leading to an imbalance in the proportion of organic matter in the bone, thus hindering the early healing of the fracture. However, the fresh meat bone soup has a delicious taste and can stimulate appetite, so eating a little is not harmful.

　　6. Avoid partial dieting

　　Fracture patients often have local edema, congestion, bleeding, muscle tissue injury, and other conditions. The body itself has resistance and repair ability to these, and the raw materials for the repair of the body's tissues, the growth of long bones, the formation of callus, and the removal of blood stasis and swelling rely on various nutrients. Therefore, the key to the smooth healing of fractures is nutrition.

　　7. Avoid indigestible foods:Fracture patients may have activity restrictions due to the fixation of plaster or splint, and the swelling and pain at the injury site, along with mental anxiety, so their appetite is often poor, and constipation may occur occasionally.

　　Surgical Treatment

　　1. Indications:If the patellar fracture exceeds 2-3mm of displacement, the joint surface is uneven over 2mm, and there is a fracture with a tear of the extensor support band, it is best to use surgical treatment. The purpose of treatment is to restore the shape of the joint surface, repair the patellar extension device and firmly internal fixation to allow early activity.

　　2. Surgical Approach:The patellar pre-patellar transverse incision, the arch apex is 1mm to 1.5cm below the inferior pole of the patella, and both sides to the midpoint of the lateral sides. This incision can fully expose the fracture fragments, fracture reduction and repair of the extensor muscle expansion and synovial tear. According to the condition of skin abrasion, the median longitudinal incision of the knee or the lateral incision beside the patella can also be adopted. Incise the skin and subcutaneous tissue and separate towards the proximal and distal ends, exposing the anterior surface of the patella, the quadriceps tendon, the patellar tendon, and the medial and lateral expansions. Through the tear of the expansion, thoroughly remove the joint hematoma and bone fragments. Use two large gauze forceps to reduce the fracture fragments, touch the joint surface through the expansion, and repeatedly adjust the position of the gauze forceps to achieve a smooth joint surface by hand. The gauze forceps are temporarily fixed, and internal fixation is adopted according to the fracture condition, and finally, the expansion is repaired. The improved tension band wire, using two 2mm Kirschner wires to pass through the superior pole of the patella, through the fracture block from the inferior pole, the two needles are located on both sides of the quadriceps tendon and are parallel, and then using 18# wire, wrap around the four tips of the Kirschner wire to fix.