Also known as: Multiple broken ribs on both sides
Derek Shepherd's flail chest injury from a car accident is discussed in detail at the dinner party. Penny reveals she was the resident who treated him that night, and that the decision to prioritize his chest injury over obtaining a CT scan contributed to missing his fatal brain bleed.
Also known as: Brain bleed
Derek's fatal brain bleed was missed because a CT scan was not performed. Penny mentions there was a scalp laceration but no step-off, and she believed he needed a CT but didn't push hard enough for one. This is the central medical case driving the episode's emotional conflict.
Also known as: UTI
Maggie develops a UTI with burning symptoms after having sex with an intern. She goes to the ER during the dinner party seeking treatment and STD testing, concerned about potential sexually transmitted infections.
Also known as: Dislocated shoulder
Callie is called away from the dinner party to handle a posterior shoulder dislocation case in the ER when a fellow is unable to manage it properly.