I’ve been having a knee problem on and off for the last few months. During my the last few years I had; tennis elbow, Achilles tendonitis and then finally Achilles tendon rupture and now for the last few months my right knee sometimes gives way during games, becoming unstable. Did anyone had a similar experiance? There is no pain on my knee but it does feel stiff. I have not worn a knee support and now will consult with my GP, request him to examine it and send me for x-ray and MRI scan.