I had open excision of bipartite patella and lateral release to my left knee in August 2014. I had a hematoma and potential infection so they did a clean out in September 2014. I was still experiencing pain and tightness in my knee as well as in the quad tendon but have been able to resume training with running, squatting, jumping, etc. Laying on my back, lifting my leg, and bending my leg back and forth usually creates some discomfort and a little grinding in the knee. At night prior to going to bed I always stretch. The other night I was performing the couch stretch. During the stretch I heard and felt a very loud pop directly in my knee. The past few days I have had significantly less pain and pressure in my knee. I'm able to do many of my athletic movements without any pain during the exercise or residual pain the next day. I'm looking for any help to explain what potentially the pop was and why I have significantly less pain now. Any chance that the pain and pressure could return? Any help would be greatly appreciated!!