Certified Surgical First Assistant (CSFA) Practice Test

A sigmoid colostomy is brought through what structure?

1. Transverse muscle

2. Rectus muscle

3. External oblique muscle

4. Diaphragm muscle

The correct answer is: Rectus muscle

The sigmoid colostomy is typically brought through the abdominal wall, specifically involving the rectus muscle. The rectus abdominis muscle is the primary muscle of the anterior abdominal wall and is crucial in the creation of a colostomy as it provides a pathway for the sigmoid colon to exit the body at the stoma site. This surgical procedure is performed when there's a need to divert fecal waste away from the lower intestine due to various conditions, such as obstruction or disease. During this procedure, the surgeon will create an opening (stoma) by bringing a segment of the sigmoid colon through an incision made in the abdominal wall, which incurs the involvement of different muscular layers – notably the rectus abdominis. The relationship of the colostomy to the rectus muscle underlines its significance in securing both proper anatomical placement and an adequate blood supply to the stoma. The other muscles listed, while important for overall abdominal support and function, do not play the principal role in the creation of a sigmoid colostomy, which is why they are not the correct choice in this context.