The knee joint is the largest and most complex joint in the human body, and it is very common to see patients with knee pain in the clinic. Whenever I see a patient like this, I have to tell them that they must confirm the location of their knee pain before treating it. In clinical practice, I divide knee diseases into two types: intra-articular lesions and extra-articular lesions. Common intra-articular lesions are: patellar tenderness, osteoarthritis, meniscal damage, synovitis. Check for ligament injuries ……; common extra-articular lesions are lateral collateral ligament injury, patellar ligament injury, N tendon curl, soft tissue injury of the circumflex knee, deformity of the knee joint in the later stages of knee arthritis ……. For lesions within the knee joint, ozone water (liquid) is often given with the application of joint cavity lubricant, which is a purely green therapy with no adverse effects, non-addictive, non-invasive, and uses the anti-inflammatory and pain-relieving effects of ozone instead of oral medication, with obvious results. For extra-articular lesions, arc-blade needle knife release is often required in conjunction with anti-inflammatory paroxysm injection. For severe extra-articular patients, arc-blade needle knife release is used to restore the balance of soft tissues around the knee joint, correct the knee joint force lines, prevent further deformation of the joint, and prolong the life of the joint. In short, problems with the knee joint must be promptly seen in a regular hospital, do not believe in the false propaganda of a cream to treat all painful diseases!