Which muscle is not associated with retroperitoneal abscess formation?

The rectus abdominis muscle is not associated with retroperitoneal abscess formation because it is a muscle located in the anterior abdominal wall, rather than within the retroperitoneal space. The retroperitoneal space is primarily situated between the posterior abdominal wall and the peritoneum, housing structures like the kidneys, ureters, and major blood vessels.

In contrast, the psoas, iliacus, and quadratus lumborum muscles all reside in or near the retroperitoneal space. The psoas muscle, for instance, is a key player in many abdominal muscular functions and can be directly involved in the development of retroperitoneal abscesses, especially in cases of infection or inflammatory processes in the nearby organs. Similarly, the iliacus muscle, which works along with the psoas, can also be implicated due to its proximity to the retroperitoneum. The quadratus lumborum muscle, located in the posterior abdominal wall, while less commonly associated with abscesses than the psoas or iliacus, still occupies the retroperitoneal space and could potentially be involved in various pathological processes within that area.

Thus, the rectus abdominis, being anterior and outside the