If you have pain behind the knee, and it’s limiting your flexion, there’s a good chance it’s a Baker’s cyst. These are benign collections of fluid. The build up of fluid is what prevents bending of the knee. Under normal circumstances, fluids come and go but when there is an inflammatory process such as a meniscus tear or arthritis, and it exceeds the rate of evacuation of fluid, you get a cyst.

The lymphatic system is the system of your body that handles swelling. If there is any inefficiency in that system from past surgeries or just stagnation of fluid, you’ll have more difficulty facilitating that system. It requires the pump action of muscle to get the lymph moving. That’s why the good ‘ol “walk it off” actually has merit. However if you have a blockage, getting manual lymphatic drainage can help. It’s kind of like having a boulder in a river; the water will flow around it, however it’ll create resistance. 

If you don’t have access to a therapist that does this, here is a way you can at least start to get some lymph moving:

https://www.youtube.com/watch?v=V6uNhDCce8Q

Also, using a bike can be a great way to stimulate lymph. When you bend and straighten your knee, it’s like a mechanical pump and can really reduce the stiffness:

https://www.youtube.com/watch?v=eWJps5Y0eH8

Sometimes the muscle behind the knee can contribute. You can use a ball in combination with some gapping like so:

https://www.youtube.com/watch?v=m9Zd2eAmzBA

Finally, one of my favorite tools is the Marc Pro. It’s a form of electric stimulation that pumps the muscle for you:

https://www.youtube.com/watch?v=ptzRGeeEajQ&pp=0gcJCQMKAYcqIYzv

There are 6 main collection areas of the body. One large one is behind the knee. This is likely why Baker’s cysts are so common. They are exceptionally common following knee replacement due to the insult on the lymphatic system. If you’ve had a knee replacement, or plan on getting one, you’ll want to check out this program:

https://www.dcfmed.com/The-Total-Knee-Replacement-Protocol