Patellar tendon rupture

　　Due to the injury of the extensor mechanism usually occurring during a sudden flexion of the knee joint and a sudden and strong contraction of the quadriceps femoris, and at this time, the patella is the fulcrum of the entire extensor mechanism of the femoral condyle, therefore, the injury of the extensor mechanism is mostly patellar fracture, while the rupture of the quadriceps femoral tendon and patellar tendon is relatively rare. The typical traumatic mechanism is the sudden and strong protective contraction of the quadriceps femoris when the knee joint is flexed without preparation, leading to degeneration or rupture of the degenerated or weak patellar tendon.

　　The symptoms of patellar tendon rupture are often not serious in the early stage, and rest or taking general painkillers can alleviate them. The lesion develops continuously in a 'hidden state' until it develops into patellofemoral arthritis. Severe cases may have limited extension and flexion of the knee joint, unable to stand on one leg. In the late stage, when patellofemoral osteoarthritis has formed, there is significant destruction of cartilage and subchondral bone in the lesion area, and cartilage has no ability to regenerate and repair. In addition, this disease is prone to complications such as meniscus injury and traumatic arthritis. Secondly, once the disease is diagnosed, immediate surgery is required for ligament repair and fixation of the joint to avoid movement. After 8 weeks of fixation, the cast can be removed, and the rehabilitation training can be gradually strengthened to promote the recovery of the condition.

　　Patellar tendon rupture often occurs in people over 40 years old, and the rupture site is mostly at the inferior pole of the patella and the tibial tuberosity. After trauma, patients may experience typical extension difficulties, tenderness and hematoma at the rupture site, an empty and discontinuous patellar tendon, and upward displacement of the patella.

　　Due to the injury of the extensor mechanism usually occurring during a sudden flexion of the knee joint and a sudden and strong contraction of the quadriceps femoris, and at this time, the patella is the fulcrum of the entire extensor mechanism of the femoral condyle, therefore, the injury of the extensor mechanism is mostly patellar fracture, while the rupture of the quadriceps femoral tendon and patellar tendon is relatively rare. Therefore, it is important to remain calm and avoid emotional excitement to prevent this disease. Secondly, early discovery, early diagnosis, and early treatment are also of great significance for the indirect prevention of this disease.

　　There are no related laboratory tests for patellar tendon rupture, but X-ray films (lateral view) can show the shadow of patellar tendon rupture and avulsion of the tibial tuberosity, which can be used as an auxiliary examination for distinguishing patellar tendon rupture. Once diagnosed, we need to receive timely treatment to avoid delays and more troubles.

　　Patients with patellar tendon rupture should be given high-protein, high-calorie foods such as eggs, milk, ducks, meats, etc., to ensure adequate nutrition intake every day and promote recovery. To enhance appetite, mild activity for 4 to 5 minutes before meals can be performed, and meals can be shared with family members. The diet should be changed frequently, and attention should be paid to color, aroma, and taste; when the appetite is poor, small and frequent meals can be taken. At the same time,健脾开胃 drugs such as hawthorn and yam can be given.

　　There are many types of patellar tendon ruptures, and their treatment methods are not the same. The specific methods are as follows:

　　The rupture of the patellar tendon at the inferior pole of the patella

　　Make a median incision in front of the knee, about 12cm long, exposing the inferior pole of the patella and the patellar tendon rupture. Remove the hematoma, extend the knee to bring the two ends close together, drill two parallel fine bone tunnels longitudinally on the inferior pole of the patella, suture the ends of the patellar tendon to the inferior pole of the patella with high-strength nylon thread, repair the surrounding soft tissue.

　　Two: Tibial Tuberosity Avulsion

　　The avulsion of the patellar tendon on the tibial tuberosity can be a ligament avulsion without a bone block, but more often a tibial tuberosity avulsion fracture. Typical signs are the upward movement of the patella and the 'floating' and tender tibial tuberosity. The surgical management of the avulsion of the patellar tendon on the tibial tuberosity is relatively simple, with the tibial tuberosity fixed with a 'U' shaped nail or screw and the patellar tendon sutured to the tibial tuberosity. The range of postoperative training activities is determined according to the firmness of the fixation.

　　Three: Surgical Management of Old Patellar Tendon Rupture

　　Reconstructing Old Patellar Tendon Rupture: Before surgical repair of old patellar tendon rupture, perform patellar traction. Use a Kirschner wire to traverse the proximal part of the patella horizontally, do not enter the joint cavity. Through the traction of the Kirschner wire, for 1 to 4 weeks, extend the quadriceps muscle to a sufficient length for surgical repair. If there are no signs of infection at the skin needle holes, the Kirschner wire can be retained until the end of the surgery and then removed.

　　1. Surgical Method: Make a 'U' shaped incision in front of the knee, try to avoid Kirschner wires, expose the patellar tendon, remove all scar tissue, free the patellar tendon, and make appropriate adjustments to its ends. Drill a 6mm diameter bone tunnel transversely in the middle 1/3 of the patella, do not enter the joint cavity. Use the Kirschner wire retained on the patella or a hemostat to pull the patella downward, narrowing the distance between the two ends of the patellar tendon. Then take a 20cm long fascia lata strip from the healthy side of the thigh, pass it through the transverse bone tunnel of the patella. Tighten the fascia lata and suture its ends to the distal ends of the patellar tendon. The remaining fascia lata strip is woven to reconstruct the patellar tendon, repair the defect, and suture its free end to the newly formed ligament. To reduce the tension at the suture site before the patellar tendon heals, use a wire wrapped around the superior margin of the patella, with the two ends fixed on the bolts crossing the tibial tuberosity.

　　2. Postoperative Treatment: Use the above tension reduction methods, retain the tension wire for 8 weeks. Begin the quadriceps exercise as soon as possible. Allow the knee to move within 30°.