Which condition is characterized by an obstruction caused by paralysis?

Paralytic ileus is a condition where there is a functional obstruction of the intestine due to a lack of peristalsis, which is the wave-like muscle contractions that move food through the digestive tract. This lack of movement can be caused by various factors such as surgery, infections, certain medications, or underlying diseases. In the case of paralytic ileus, the intestines are not physically blocked by a mass or strictures, but rather, they are in a state of paralysis, leading to an inability to properly convey contents through the bowel.

In contrast, options like obstructed hernia and appendicular obstruction refer to physical blockages. An obstructed hernia occurs when a portion of the intestine gets trapped in a hernial sac, creating a mechanical blockage. Appendicular obstruction refers to blockages associated with the appendix, which could also be due to an appendiceal mass or inflammation. Ileus caused by mechanical factors pertains to situations where a physical obstruction, such as scarring or tumors, impedes the movement of intestinal contents.

Thus, the defining feature of paralytic ileus as a condition driven by paralysis sets it apart from the other choices, which involve mechanical causes of obstruction.