Amputated limbs and their development over time
A character of mine may have had his hand amputated when he was seven years old (I write 'may', because it isn't absolutely necessary to the plot. He's going to have to be castrated, however, but it somehow makes sense for the people who did it to make sure that his sword hand is chopped off as well, and I could fill his head with all kinds of lovely conceits about Maedhros and Beren etc.). He's now twelve and will be eighteen by the end. What I'm wondering about and needing to find websites about is whether his arm and the scar will grow normally with him or if he'd need to exercise it somehow to make sure that the musculature develops as it should (have no idea how common amputation is in paediatric surgery, nor how the bones will develop). Physiotherapy and prosthetics don't seem to be that advanced in the Fourth Age of Middle-earth, but they might be able to think of something.