Knee pain. When will i start running?

Hello,My knee got fractured in march 2016, while playing cricket match. it was lower end of femur fracture. Doctor put only plaster for 21 days and then it was removed. since then pain has not gone from the knee. even i fee some vibration in the knee. as per the latest MRI done 4 months back dr. said knee is ok but i am afraid of this pain because its been 1 year now. sometimes sharp pain occurs. i need to know when will i start running ? I would llike to inform that as per the MRI done in March 2016, problem was Fracture of lower end of femur. and conclusion was: 1). undispalced crescentic fractured noted in non weight bearing surface of lateral femoral condyle with surrounding significant marrow edema. 2). Grade 1 strain of anterior cruciate near its tibial attachment. 3). Also focal marrow edema noted in anteromedical aspect of proximal tibia. please help.