I am 19 days post partial replacement of my left knee (did the right knee last year). My surgeon gave me the go-ahead to massage ginger essential oil into my knee to help reduce the swelling, as long as I avoid getting it on the incision. I've been using it 1-2 times per day. It's slow, but it is definitely working. After one day, the swelling was less squishy. As the swelling goes down, your range of motion will improve.
If anyone is interested, this is super easy to make, and inexpensive. I make it in small batches. Mix one ounce of jojoba oil with 20 drops of ginger essential oil and put it in a spray bottle (glass, either cobalt blue or amber, to protect the essential oil from the light). That's it. Everything is available online. You can also get the everything at World Market or Sprouts if you don't want to wait.