Hi I know this post is a few years old and hopefully you have had the mirena removed by now and seen an improvement in your symptoms. After reading your post I had to comment as reading your symptoms and the effect the mirena had on you struck a chord with a condition I am currently in the process of being diagnosed with.
From your symptoms it sounds highly likely you could have a form of Ehlers-Danlos Syndrome. I strongly suggest you look into this, it is a connective tissue disorder where you don't produce enough collagen and the collagen you do produce us mutated.
The hormone progesterone in the mirena can inflame symptoms severely making these connective tissues more lax. This would explain your ligament damage. Although surgery can help it is not advised in EDS patients as you can damage the already faulty tissues, causing the problems to return more severely in future.
Please check into this condition as it can affect some of your organs, due to them being held by connective tissues. There are 6 different types and every case varies from which traits you inherit from that particular type.
There is a simple test called the Beighten Score test that allows you to check for the Hypermobility type of EDS although people suffering from this type can lose their flexibility with age. There is information on both the EDS website and HMSA website.