It is absolutely possible to keep most of the muscle intact during the surgery. What do you think happens when football stars have knee or muscle surgeries or even bone fracture and they stay in bed for weeks/months ? If one takes good quality proteins, BCAA, glutamine, creatine, eats high quality of protein food (meet, milk, eggs, fish), and the most important, goes into surgery with already huge amount of muscle mass so that it is more difficult to effectively run out of it, it is absolutely possible to finish consolidation with a good, above average muscle mass.
Now, of course all these things are expensive, require that for the most part somebody is with you to take care of you, but it is possible. People who have been doing body building, even at amateur level, know how to do it. People who stumbled across ''shocking and derogatory'' article about random dude who did LL , research the procedure and decided to go for it the next day, well, it will be more difficult. Shy Shy has specified that he knew about that since his middle 20s, did a tone of researched, prepared very well , physically, psychologically, and financially, and got great results. Many other people do too, we simply don't hear about them that often.