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: Surgery
Progression of congenital scoliosis is least likely in which of the following veebra anomalies? 
Select and explain. 
A. Fully segmented Hemiveebra, B. Wedge veebra, C. Block veebra, D. Unilateral unsegmented bar with Hemiveebra
C: Block veebra
Answer: C: Block veebra 
Explanation: Block veebra type of scoliosis has the best prognosis. The progression is slow and it can be corrected easily, whereas unilateral thoracic unsegmented type carries worst prognosis. Ref: Ohopaedic Surgery Essentials in Pediatrics By Kathryn E. Cramer, Susan A. Scherl, 2004), Page 65; Campbell's Ohopaedics, 11th Edition, Page 2607.