Yes, I know about this... When I dislocated my right knee, years ago.. What a painful thing that was. The pain from it went right to my big toe also.

The ortho I went to asked nothing about it.

So when I was thru with the ortho --had the shot in the joint after Xray and MRIs... I went to a chiropractor who reset my knee. On the entry sheet to fill out there was a diagram of the legs...and it asked for the areas of pain... so I drew it out there.

After she snapped my knee back (why couldn't the DOCTOR do this?--- he wanted to do a knee replacement is why)... the pain in my toe INSTANTLY stopped! This is why when I have to use a Lidoderm in bad pain times... I place it along the back of that knee, and it works in one day for me.

The ortho explained that as we age, our cartilage gets thinner and the knee tends to slip with the increased spaces created.
So I got a knee brace to hold my knee when walking long distances or stressing at the gym. And I started the SAMe to rebuild my cartilage. Both work well for this. 400mg of SAMe daily on an empty stomach in the morning. (Costco is affordable for this).

I too had dislocated that knee walking down a hill. We live in a hilly place and I had that happen the day after a long walk. I think it is the coming DOWN the hill that does it for me.