This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Avascular Necrosis & Osteochondroses, Subject name: Orthopaedics
Kohler's disease involves: 
Select and explain. 
A. Femoral head, B. Navicular bone, C. Tibial tubercle, D. Lunate bone
B: Navicular bone
Answer: B: Navicular bone 
Explanation: (Navicular bone) (269-M)Common osteochondritisNameSite affected* Perthes' disease- Femoral disease* Fanner's disease- Capitulum* Keinbock's disease- Lunate bone* Osgood shlatter's disease- Tibial tubercle* Sever's disease- Calcaneal tuberosity* Kohler's disease- Novicular bone* Fricberg's disease- Metatarsal head* Scheurmann's disease- Ring epiphysis of vertebrae* Calve's disease- Central bony nucleus of vertebral body