Hello, I have gone through your query and understand your concerns. Unfortunately, without a thorough exam it is not really possible to tell exactly what is going on. In the area you describe, there are the peroneal tendons, as they sweep down behind then under the lateral malleolus (outside ankle bone). These tendons can become pinched in the ankle joint at times. You could have some synovitis inside the ankle joint, which is being pinched within the joint. Sometimes, loose bodies or talar dome lesions can cause sharp pain inside of the ankle joint. If the problem continues, you might want to see an orthopedic surgeon for an evaluation. Good luck.