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He completed his residency in Orthopaedic Surgery at Northwestern University Medical School Affiliated Hospitals and completed training as a clinical fellow in pediatric orthopaedics at the Alfred I. duPont Hospital for Children [ 1 ] , Wilmington , Delaware .
 Orthopaedic, Northwestern, Medical, Alfred I. duPont Hospital for Children, Wilmington , Delaware
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Orthopaedic, Northwestern, Medical, Alfred I. duPont Hospital for Children, Wilmington , Delaware