I Have Recently Been Told I Need A Knee Replacement

I have recently been told I need a knee replacement due to an MRI showing cartilage missing in my knee. Previous sharp, long-term foot pain was diagnosed as arch starting to fall. Now, the little finger on my left hand hurt feels like the osteoarthritis in my hands has suddenly taken a massive advancement. talkiing bone on bone like the knee.
About a month ago, I started having blurred vision - this is intermittent - lasts usually for just a few minutes at a time. I had one incident with what can only be explained as a halo effect of sorts in the periferal vision on my right eye I want to know if these symptoms can be related or if they indeed just things that happened close to each other.