Meniscus damage
Introduction
Introduction to meniscus injury Knee meniscus injury (meniscustear), rupture of the semilunar fibrocartilage in the knee joint. The meniscus is located between the femoral condyle and the tibial plateau, one inside and one outside. In daily life, when the knee joint is flexed and rotated, the meniscus also has corresponding movements. From the shape, as a wedge-shaped filling, to meet the needs of the femoral condyle; from the function, it plays an important role in conducting load, maintaining stability, and distributing synovial fluid. Once the meniscus has been ruptured due to prolonged wear or acute injury, it partially or completely loses its original function, and even forms interference in the joint, affecting the normal movement of the knee joint, and it can be followed by osteoarthritis. basic knowledge The proportion of sickness: 0.01% - 0.02% Susceptible people: no specific people Mode of infection: non-infectious Complications: radial artery injury edema
Cause
Cause of meniscus injury
Causes
In daily life, various movements of the knee joint cause the meniscus to constantly withstand the vertical pressure of the conductive load and the horizontal tension that is displaced toward the circumference and the shear stress when rotated. The mechanism of meniscal injury is the meniscus contradictory movement caused by knee joint movement and sudden changes in motion. When the knee joint is to be stretched (or flexed) and at the same time to be internal (or external), the one side meniscus will be in a contradictory state, both forward and backward. The knee joint is in a semi-flexion position. When the calf rotates, the meniscus is squeezed and cannot move. If the knee is suddenly straightened or further rotated, the tensile force of the fibrous tissue of the meniscus itself or its peripheral fibrous tissue is When it exceeds its own endurance, tearing occurs. The medial meniscus is moved backwards in the long-term or the laborer. The base angle is squeezed between the two squats and the anterior horn is pulled. Long-term crush wear can cause degeneration and easily cause tearing. The abnormal meniscus loosening, unstable after joint ligament injury, or obesity, excessive weight, etc., are all factors that are susceptible to injury.
Prevention
Meniscus injury prevention
(1) Give local pain relief and symptomatic treatment.
(2) X-ray examination to the hospital, clear dislocation or presence or absence of fractures, but the x-ray can not show the meniscus status, the knee joint MRI should be performed to determine the presence or absence of meniscus injury.
Complication
Meniscus injury complications Complications radial artery injury edema
The main complications of arthroscopic surgery are infection, blood vessels, nerve damage, synovitis and rare joint leakage. The infection rate is less than 0.5%, nerve damage is less than 0.1%, and vascular injury is rarely reported.
Due to the injection of surgery, knee swelling is the most common, joint blood is usually due to lateral release, meniscus repair, shallow vascular hemorrhage at the entrance site, brachial artery injury is rarely reported, but must be paid attention to, when nerve damage occurs In addition to tourniquet paralysis or local edema compression should also consider whether the nerve is ligated when the meniscus is repaired, at this time can be surgically explored.
Symptom
Meniscus injury symptoms common symptoms joint pain joint swelling
Meniscus injuries are more common in miners, porters, and football and basketball players. Patients have a clear history of trauma, with the exception of long-term laborers or those with unstable joints for some reason. After an injury, the pain often occurs in a specific position, and the pain disappears after the position changes. Some patients will block the formation of the torn meniscus, causing the joint to temporarily interlock and not move. There is blood in the joint cavity, and there is a tender point in the plane of the medial or lateral joint space. After a few weeks, it swollen. The flexion and extension function is restored, but when it is often affected, the joint is unstable, and there is a foreign body sensation, and the quadriceps muscle has atrophy. After the meniscus injury, the knee joint has severe pain, can not automatically straighten, and the joints are swollen. The tenderness at the knee joint is an important basis for meniscus injury.
Examine
Meniscus injury examination
1. X-ray examination: The purpose of the film is not to diagnose the meniscus tear, but to exclude osteochondral free body, exfoliative osteochondritis and other knee joint disorders that may be similar to meniscus tear, arthrography It is a valuable auxiliary measure for the analysis of knee joint diseases, but due to non-invasive and high-accuracy examination methods such as modern MRI, contrast technology has been used less frequently.
2. MRI: It is the imaging test method for diagnosing meniscus injury, cruciate ligament rupture and other positive sensitivity rate and accuracy. The accuracy rate is 98%, and the MRI of meniscus tear is low signal in the meniscus. A high signal band of a linear or complex shape runs through the surface of the meniscus. Other imaging diagnostic methods, such as high-resolution ultrasound of the knee joint and high-resolution CT, are also helpful in the diagnosis of intra-knee disorders.
3. Arthroscopy: Arthroscopic technique has been recognized as the most ideal diagnostic and surgical treatment for meniscus injury, but arthroscopy should not be a routine means of meniscal tear, only in the clinical meniscus tear After the initial diagnosis, arthroscopy can show its superiority in confirming the diagnosis and performing arthroscopic surgery at the same time.
Diagnosis
Diagnosis of meniscus injury
History of trauma, localized localized pain, joint swelling, squeaking and interlocking, medial head atrophy of the quadriceps, local tenderness, McMurray test (+), Apley grinding test (+), X-ray examination except for other bone disorders, MRI examination can confirm the diagnosis.
