This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Orthopaedics
Osgood Shattiler disease - 
Select and explain. 
A. Involve the knee joint, B. Pelvis, C. Wrist joint, D. Cervical spine
A: Involve the knee joint
Answer: A: Involve the knee joint 
Explanation: Osgood-shaltter disease is osteochondritis of tibial tuberosity (just below the knee joint).