I came across this set of articles written by a surgeon who has experience mending torn muscles in trumpet players. There are some pictures of the surgery, just FYI.
1. Jaime Planas, Barcelona Spain: Plastic and Reconstructive Surgery on Embouchures
2. Another Ruptured Orbicularis Oris Case
A blog about a French horn player's journey with Focal Embouchure Dystonia; one of the only existing documentations of rehabilitation through videos and writing spanning over a decade. This blog shares resources, research, and information on FTSED and other music performance related injuries. Katie also advocates awareness, education, does presentations, provides guidance; and brings the musicians dystonia community together thru online groups, streamed interviews and conversation.