Meniscus injury is one of the most common knee injuries, more common in young and middle-aged adults, with more males affected than females. According to foreign reports, the ratio of medial to lateral meniscus injuries is 4-5:1, while in China, the ratio is reversed, at 1:2.5. The meniscus in the human body is a crescent-shaped fibrocartilage, located on the medial and lateral articular surfaces of the tibia plateau. Its cross-section is triangular, with the outer part thicker and the inner part thinner, the upper part slightly concave to fit the femoral condyle, and the lower part flat, connecting with the tibial plateau. The function of the meniscus is to stabilize the knee joint, distribute the load of the knee joint, and promote nutrition within the joint. It is due to the stabilizing load-bearing effect of the meniscus that the knee joint can bear heavy loads for years without injury. Meniscus injuries are often caused by a twisting force, where when one leg bears the weight, the lower leg is fixed in a semi-flexed, abducted position, and the body and thigh are suddenly internally rotated, causing the medial meniscus between the femoral condyle and the tibia to be subjected to rotational pressure, resulting in meniscus tears. In the early stage, knee pain and swelling can be observed, and over time, there may be tenderness on the medial and lateral sides of the knee, atrophy of the thigh muscles, and 'weak legs'. Doctors can also assist in diagnosis through special physical examinations, such as the McMurray sign.
The acute phase of meniscus injury is characterized by significant pain, swelling, and effusion in the knee joint space, as well as impairment of joint flexion and extension activities. After the acute phase, swelling and effusion can resolve spontaneously, but pain still persists during activities, especially when going up and down stairs, squatting, and jumping. The pain is usually located within the joint space, occasionally in the posterior part, with a sensation of 'tightness'. Severe meniscus injuries can lead to limping or functional impairment of flexion and extension, with some patients experiencing a 'locking' phenomenon, where the fractured part of the meniscus slips into the joint space, causing mechanical obstruction and hindering joint extension and flexion activities, or producing a clicking sound during knee flexion and extension.
In the acute stage, if there is obvious effusion or hemarthrosis in the joint, the effusion should be aspirated under strict aseptic conditions; if there is a 'lock', the lock can be released manually, but most often surgical treatment is required to release the cause of the lock. Actively exercise the quadriceps femoris muscle, take the knee joint in a straightened and tightened position, with the toes pointing upwards, lasting for 5 seconds as one repetition, 20 repetitions as one set, and do one set in the morning and afternoon to prevent muscle atrophy.
In the chronic stage, if non-surgical treatment is ineffective and symptoms and signs are obvious, the damaged meniscus should be surgically removed in a timely manner to prevent the occurrence of traumatic arthritis. The patient should apply pressure bandage in the extended knee position after surgery, walk on the second day, and perform functional exercises. Generally, normal function can be restored within 2-3 months after surgery.
Arthroscopy can treat meniscus injury. Arthroscopic surgery is currently the most recommended minimally invasive surgical method for treating knee injuries. It has minimal trauma, rapid recovery, and can be used for the treatment of meniscus injury.