I'm glad basketball is a limited contact sport because I'm not good at it and I'm brittle boned
DO you play basketball now?
Nah, I do brazillian jiu jitsu now, it's a full contact sport, my bones are much less brittle now
Oh yes, I would say Jiu Jitsu is much more contact then basketball. 
BJJ is a combat sport with high level problem solving and dire physical consequences
Is it similar to Karate or Tae Kwon Do?
It is more of a ground fighting sport, centered on take-downs and following the movement of your opponent.