Sadly things have recently got worse for me.
It turns out that my fall a month or so ago, has shattered part of my knee cap, and I now seemingly have a big hole in it!
Despite pain at the time, I rode without knowing about the injury for roughly the last 27 miles of the ride on the day, and have been riding with the injury ever since, simply because there has not been any pain or discomfort. It is only over the last week that things have come to head after doing some ladder work, and my knee now also looks like the alien elbow.
Other than fluid on the knee and burning pain, there is still no major pain which is very odd, but it has certainly spoilt the chances of getting out for a ride over the last week and foreseeable future.
SW has a valid point about wearing protective items when riding off road, even if it just elbow and knee pads. I have set of Dainese knee pads and the injury wouldn't have happened if I had been wearing them