Seven months and finally man, MRI and MD met in the same room. To begin - no meniscus tears; ACL, PCL and collateral ligaments were intact. Cruciate ligaments were intact and my patellar facets appeared especially well-preserved.
However I had a focal osteochondral injury or lesion. The doctor called it a "pothole" in my knee, the result of bone erosion. No idea how long it's been there or even if running was the cause. However it's there now. He mentioned three cures, but all would necessitate not running any more. I'm free to run or walk now, but all such activity will continue eroding the pothole. Since I'm not in anything like steady discomfort, the doctor suggested leaving the pothole alone, and, when the pain eventually picked up, selecting from the cure hat trick.
A most curious state. I'm going to have to have a procedure done eventually and so the temptation is to use up the knee while I still can. But I'm sort of numb and need to take time to let all this sink in.
I have no passion for any other sport.