UPSC-CMS 2018 — Orthopaedics

Question 1: Which one of the following bones is affected in Keinbock's disease?

• A. Lunate bone (Correct Answer)
• B. Capitellum of the humerus
• C. Metatarsal
• D. Navicular bone

Explanation: ***Lunate bone*** - Kienbock's disease is an **avascular necrosis** of the **lunate bone** in the wrist, leading to its collapse and fragmentation over time. - This condition is often associated with repetitive trauma, negative ulnar variance, and altered blood supply to the lunate. *Capitellum of the humerus* - Avascular necrosis of the capitellum is known as **Panner's disease**, which is distinct from Kienbock's disease. - Panner's disease primarily affects children and adolescents, often due to repetitive throwing or overhead activities. *Metatarsal* - Avascular necrosis of the metatarsal heads is seen in conditions like **Freiberg's disease**, which typically affects the second metatarsal. - This condition presents with forefoot pain and differs significantly in location and affected bone from Kienbock's disease. *Navicular bone* - Avascular necrosis of the tarsal navicular bone is referred to as **Kohler's disease**, predominantly appearing in young children. - This condition affects the foot and is not related to the wrist pathologies seen in Kienbock's disease.