I've been diagnosed with an aneurysm behind the knee. the dr. said it is 2.3cm - 2.4cm. can it cause pain in the front like arthritis?

Popliteal Aneurysm: It sounds like a popliteal aneurysm. You should see a vascular surgeon. The risk with these aneurysms is clot forming and embolizing down the leg. Also, there is an association with aneurysms in other parts of the body. You should be screened and evaluated by a vascular surgeon.

Not usual: Many popliteal aneurysms have no symptoms until they clot. The bulge, pulsation, or some posterior knee discomfort is more likely. These are common on both sides and can have other related aneurysms that need to be checked ( abdominal aorta scan). One can have arthritis and an aneurysm.