I've had a sore left knee since the Wonderland 25km trail run. Sometimes I've been able to run, sometimes it's been too sore to run.
It's an injury to the medial meniscus and the popliteus muscle (behind the knee) has been strained.
Started some strengthening exercises (as my left leg muscles are now weaker) and a graded return to running, by planning to run 5km approx on alternate days.
After the Easter 3 days orienteering and a 2day bushwalking in steep terrain I can say that my knees are both ok