The side effects of sodium vitreous acid injection into the knee joint rarely occur, but they can occur under certain circumstances: 1. The most serious side effect is knee joint infection, where the joint cavity injection causes external bacteria to enter the joint cavity and cause joint infection, and joint infection has serious consequences; 2. If the organism is allergic to the ingredients of sodium vitreous acid, it will lead to itching and various allergic symptoms around the knee joint, and the treatment needs to be stopped immediately; 3. Sodium vitreous acid injection into the synovial membrane can cause severe pain in the knee joint; 4.