People often have pain after twisting their knee, or often have pain going up and down stairs and squatting, and older people often experience discomfort or pain in the knee joint when walking, or even joint deformity. These knee problems are caused by damage to the soft tissues such as cartilage and ligaments within the joint. In the past, it was difficult to correctly diagnose the above problems. A definite diagnosis can also only be treated by cutting open the knee joint for surgery. It took months or even years to restore knee function. Nowadays, most of your knee injuries no longer require an incision and a long recovery time. Doctors can use arthroscopy to look directly inside the knee joint to diagnose and treat your condition. The arthroscope consists of a set of magnifying glasses and a glass fiber that produces a cold light inside the joint attached to a monitor, which allows the doctor to see almost any part of the knee joint. The arthroscope enters the joint through a tiny wound (about 5mm) and is able to definitively diagnose most knee injuries and treat them surgically at the same time. The entire procedure is performed under local or general anesthesia and is essentially painless. Most patients are able to walk and begin rehabilitation the day after surgery. Arthroscopic surgery is characterized by low injury, fast recovery, and high diagnostic accuracy. It has the advantages of good treatment results and minimal side effects. Currently, 2 to 3 million patients in the United States undergo arthroscopic surgery each year, with a success rate of more than 95 percent. Almost all injuries and diseases in the knee joint can be examined and treated by arthroscopy, and the most common ones are as follows: 1. Meniscal injury of the knee joint: Meniscal injury can be caused by a fall, body twist or external impact. After a meniscus injury, you will often feel pain in the knee joint when walking, and sometimes you will have the feeling that the knee joint is “pinched” and it takes some movement to resume walking. You may also experience pain in your thighs, walking up and down stairs, or squatting. Meniscal injuries generally do not heal on their own and require arthroscopic surgery to remove or repair the damaged part. 2, knee cruciate ligament rupture: people can also damage the ligament when they fall, twist their body, or have a traumatic injury to the knee. After a cruciate ligament injury, you will feel weakness (instability) in the knee joint when you walk and do not dare to run or stop quickly, mostly accompanied by thigh muscle atrophy and thinning, and pain when walking up and down stairs or squatting. The cruciate ligament rupture cannot heal on its own and requires arthroscopic surgery to reconstruct the ligament if necessary. 3, knee patellar disease: the patella (commonly known as: kneecap) is located in front of the knee joint. It mainly supports the body’s activities such as walking up and down stairs, squatting and standing up. Due to genetics, trauma, muscle atrophy and other reasons, the patella may have an abnormal shape or position (mostly shifted to the outside), so you may feel knee pain when walking up and down stairs, squatting or standing up, but there is no significant discomfort when walking and running on a flat surface. Patellofemoral disease often requires arthroscopic surgery to reduce and relieve pain when walking up and down stairs, squatting, or standing up. 4, osteoarthritis of the knee: joint degeneration caused by age-related arthritis, post-traumatic arthritis, rheumatoid arthritis disease can cause the destruction of cartilage on the surface of the knee joint. The main symptoms are joint pain when walking, restricted movement, joint extension, or joint deformity such as O-leg, X-leg, K-leg, etc. If there is mild to moderate cartilage damage, or if you are temporarily unable or unwilling to undergo joint replacement surgery, it is possible to remove bone spurs, trim the joint surface, and remove the synovial membrane to relieve pain. 5. Free body in the knee joint (joint rat): Often due to trauma or breakage of the bone spur in the joint, a fragment that can travel is called a free body. When the free body wanders into the middle of the joint, it will suddenly produce joint pain and locking, and joint movement will be significantly limited, and it will gradually recover after the free body leaves the joint space. The free body can be removed under arthroscopy. 6, synovial creases in the knee joint: when you go up and down the stairs, squatting or standing up, the knee joint is sore or weak, but walking and running on a flat surface is not limited. This is due to pain and joint instability caused by a thin film of fibrous tissue left over from congenital development at the edge between the kneecap and thigh bone, which thickens and enlarges due to trauma or inflammation, and extends into the gap between the kneecap and thigh bone to be squeezed. Conservative treatment of this disease is not ideal, and arthroscopic removal of the band can be effective in relieving the pain. 7. Chronic synovitis: Synovium is a membrane lining the knee joint, which is rich in nerves and blood vessels. Many causes can cause chronic synovitis. The main manifestation is swelling and discomfort of the joint after rainy days or exertion. Pain. Removal of the hyperplastic synovial tissue under arthroscopy can largely relieve the symptoms. 8, rheumatoid arthritis: rheumatoid arthritis is a systemic immune disease. Due to the disruption of the immune system, it destroys its own synovial tissue, leading to synovitis, and further erosion and destruction of joint cartilage, eventually forming rheumatoid arthritis. In the early stages of synovitis (before the cartilage is destroyed), synovial hyperplasia can be removed arthroscopically to slow down the rate of cartilage destruction and slow down the progression of rheumatoid arthritis. The recovery process after surgery: You will be able to walk once you have recovered from the anesthesia. Generally speaking, you can resume normal life and light work 10-15 days after surgery, walk up and down stairs and squat 21 days after surgery, and participate in some sports or normal work after 4 weeks. 2-3 months later, you can work and live like a normal person. Visits and hospitalization: If you are experiencing knee discomfort and wish to come to the hospital, you can call and schedule your outpatient and inpatient appointments in advance to reduce your waiting time at the clinic. Please bring your recent knee x-rays or MRI (magnetic resonance imaging) films and lab results.