Sorry you are going through this. It does not sound like Patella infer to me, but I think there are other posters like Pam who know more about it than I do. I understand that Patella Infera is caused by adaptive shortening of the patella tendon. It can happen if there is a substantial loss of extension over a period of time. The tendon shortens which pulls the knee cap down. It is usually diagnosed by doing X-rays with both legs in a particular bent position and then measuring difference. Since you have good extension, it does not sound like patella baja. Sounds like swelling. It does not take a lot of swelling to shut down your quad. Are you elevating the knee above your heart and icing? Follow-up with your Dr. and PT even though you were discharged. If they are not responsive, see a specialist if you can. I hope this helps.