Steven Universe's X-ray chart · 11:45am Mar 15th, 2020
This is from the 14th episode of Steven Universe Future, Growing Pains. According to Dr. Priyanka Maheswaran, there's a clear history of numerous fractures like the ones on his skull and arms. Everything is perfectly aligned and the bones healed themselves the instant the injuries occurred. To simply put, his body is durable at the level of a superhuman due to being a half-Gem/half-Diamond.
Steven has made a series of miraculous recoveries, but it doesn't change the fact that he experienced trauma. He has recovered physically, but not mentally. Dr. M further explained that adverse childhood experiences or childhood trauma (death, destruction, etc.) can have a lasting impact on how his body responds to stress, affecting his social, emotional, and physical development.
This is the episode that touches upon Steven's mental health and PTSD resulted from the events of the original series and the movie. Initially, he glowed pink which gives him tremendous strength, speed, and destructive energy output. Now, his body changed uncontrollably, which means he is on the verge of becoming a corrupted gem monster. It really hits home to those who are going through depression, anxiety, and other mental disorders.
aligns well with the theory he is going to become that monster we see in the intro