A simulation video game developed by Vanguard and distributed by Atlus, Trauma Center: Under the Knife 2 was released in 2008. Trauma Center 4 is the fourth game in the series and a direct sequel to Trauma Center: Under the Knife (2005). Under the Knife sequel Derek Stiles tackles not just the resurgence of Delphi and its GUILT sickness, but also his own personal fears and corporate manipulations three years later. The gameplay blends a visual novel-style plot with a touchscreen-based surgical simulation.
While other Wii games have adjusted their controls and gameplay in order to make them more appealing, the original game was built as a mechanical and narrative sequel using the same controls and gameplay. In addition to new co-director Hirokazu Toyama and composers Manabu Namiki and Noriyuki Kamikura, Daisuke Kanada and Masayuki Doi returned as director and character designer, respectively. Reaction to the game was largely good, however a lack of novelty was criticized by many journalists despite its many improvements. Low sales in both Japan and North America were also a problem.