Back in 2010, I was knocked off my bike. I very rarely wear sandals while cycling, but I was on this occasion, and one of my injuries was a dislocated joint in my right big toe. It was relocated by a doctor in A&E, and I haven't had much trouble from it until about 6 months ago, when I started getting pain while walking or running. This was intermittent at first, but has become more frequent, and eventually I took myself to the physio today.
The physio diagnosed osteo-arthritis, and has given me some exercises to improve the flexion in the toe. I may also try some of the Dit Da Jow oil which I bought for my wife following a recommendation by Mr B on this forum.