Swelling after knee replacement surgery is completely normal and can last up to three months after surgery, according to Arthritis Research UK. Fluid retention after surgery is also normal and especially common in the arms and legs due to lymphadema, according to Drugs.com.
After a knee replacement, swelling may occur not only in the knee but in the calf and foot as well, notes Arthritis Research UK. Icing the swollen knee for up to 20 minutes can help reduce swelling. Raising the leg and propping it up above hip height also helps reduce swelling. It is important to walk at least five minutes each hour to reduce the risk of a blood clot forming.
Lymphedema, or fluid build up, occurs because the flow of lymph is blocked, according to Drugs.com. This is most often temporary but can be permanent in some cases where multiple lymph nodes are removed. Lymphedema can occur immediately after surgery, in the months following surgery or even years later in some cases. When lymphedema occurs immediately after surgery, it can clear within a week but may last longer. Patients who are concerned with swelling or fluid retention are advised to speak with the attending physician, as an infection can cause both conditions.