What is the Normal Range of the Hiatal Aperture of the Levator Ani Muscle?

The normal value of the anal hiatal aperture is approximately 25.8 centimeters, and any fluctuation within 2.3 centimeters is considered normal.

1. Normal Range of Anal Hiatal Aperture

The levator ani muscle is a broad muscle that forms a funnel shape when joined on both sides. It joins with the pelvic surface of the pubic symphysis, the pelvic fascia and the ischial spine, and its muscle fibers converge with the contralateral muscle fibers at the midline, terminating at the perineal central tendon. The anococcygeal ligament and coccyx tip are located anterior to the perineal central tendon, with the muscle fibers of the pelvic diaphragm passing through the urethra in males and the urethra and vagina in females. The normal area of the anal hiatal aperture is approximately 25.8 centimeters, with a fluctuation range of 2.3 centimeters. An expansion of the aperture may lead to symptoms such as uterine wall prolapse and vaginal wall protrusion.

2. What is Expansion of the Anal Hiatal Aperture?

Expansion of the anal hiatal aperture refers to the presence of a tear or fissure in the patient's anus. This can occur due to excessive force during childbirth, resulting in muscle tears. In such cases, it is recommended to immediately seek professional medical attention. If the tear is large, surgical suturing may be required. If the tear is small, it is important to prevent inflammation and infection by regularly performing pelvic floor exercises.