I had that problem years ago with a split of the articular cartilage in my knee. I laid off running for about a year but walked a lot. Then I resumed running and never had another problem with it. But then everyone is different. I think the best advice is to give it rest from high intensity like running but continue to walk a lot. I have noticed that  a lot of the aches and pains and conditions we develop during running can be adapted to if one does a proper warm up. Good luck.

Almost 15 years ago, I tore the meniscus in what I considered my "good" knee.  I opted for artho because the cartilage would catch every now and then.  When they went in they found extensive wear spots (described to me as holes in my cartilage).  I was advised to not do any impact sports or my knees would wear out in half the time and if I was good they might last 20 years before I needed replacement.  So, they asked me at the time if I wanted them to drill to encourage cartilage growth and I said yes (didn't know better and was groggy from the sedation).  I'm still not sure if that was a good or bad decision, but my knee didn't feel right for a good 3 years.  I did try to run some during those first 5 years and my knee protested every time.  Running wasn't realistic to me and I stopped running for many years.

When I turned 50 I started running in Vibrams.  My knees feel better than they have in years, but the style of running is completely different.  I used to be a horrible heel striker and now I run with a forefoot/midfoot strike.  This style requires time and patience (I'm not very patient ;-)  Consequently I have quite a few setbacks, calf musle pulls and strains, achilles tendoniopathy, morton's neuroma, etc.  But, my knee hasn't been the problem.  Don't know if my knee will last an additional 5 years, but they feel good right now.

Good luck.

Ray