Side effects include nerve damage, muscle tissue damage, joint contracture, dislocations, and arthritis.
This moron is going to completely tank his own athletic ability. He'll probably be hobbling around like an 80 year old man on those stretched-out stilts.
I had a relatively minor operation in July, compared to this: tibial plateau fracture with tendon and ligament repairs. The orthopaedic surgeon told me on a scale of 1/10 it was a 9 on the 'recovery' chart of problems. Said I'll never run again and be lucky to walk without pain. I'm still in bed and on crutches 5 months later. I can only imagine with leg lengthening how much worse this would be.
AND YES: you're right about nerve damage, phantom pains, etc. You know when you've got an itch somewhere and you can scratch it for relief? With this leg: I can't satisfy that itch because it needs scratching but wherever I put my hand on that part: it doesn't resonate with what would have previously been got at, if you know what I mean? It's like I can't get to it and my brain can't register it - even though I can feel there's an itch somewhere there. Frustrating as fuck. Imagine how much worse it is on parts of your tissue/muscles/joints that have been stretched? How much worse it would be having parts of your body that have been manipulated? Fuck that.