We show that an ambiguity in setting the primitives of the matching with contracts model by Hatfield and Milgrom (2005) has serious implications for the model. Of the two ways to clear the ambiguity, the first (and what we consider more “clean”) remedy renders several of the results of the paper invalid in the absence of an additional irrelevance of removed contracts condition implicitly assume...

Materials & Methods: A retrospective review of all girls that underwent CPRE from December 1998 through September 2016 from a single institution was performed. Operative age and weight, type of pelvic immobilization, use of pelvic osteotomies, imaging, clinical course, and need for additional surgical procedures were recorded. Patients were deemed in retention if their clinical course was consi...