Why My Knee Still Hurts — What To Do If Your Knee Hurts

Why is your knee so swollen after surgery? One reason most people don’t expect — the fluid we use during the operation. During keyhole knee surgery, sterile fluid is pumped into the joint under pressure. It expands the space, improves visibility, and washes away blood and debris. Some stays in the joint. Some leaks into the soft tissues. Some pours straight out — like you see here. That’s why the knee looks swollen immediately after surgery. (Also why I wear boots to operate. Wet socks aren’t in