| Intercrural fibres of superficial inguinal ring | |
|---|---|
 The subcutaneous inguinal ring. (Intercrural fibers labeled at center.) | |
| Details | |
| Identifiers | |
| Latin | fibrae intercrurales anuli inguinalis superficialis |
| TA | A04.5.01.016 |
| FMA | 77250 |
| Anatomical terminology | |
The intercrural fibers (intercolumnar fibers) are a series of curved tendinous fibers, which arch across the lower part of the aponeurosis of the Obliquus externus, describing curves with the convexities downward.
An aponeurosis is a type or a variant of the deep fascia, in the form of a sheet of pearly-white fibrous tissue that attaches sheet-like muscles needing a wide area of attachment. Their primary function is to join muscles and the body parts they act upon, whether it be bone or other muscles. They have a shiny, whitish-silvery color, are histologically similar to tendons, and are very sparingly supplied with blood vessels and nerves. When dissected, aponeuroses are papery and peel off by sections. The primary regions with thick aponeuroses are in the ventral abdominal region, the dorsal lumbar region, the ventriculus in birds, and the palmar (palms) and plantar (soles) regions.
Contents
They have received their name from stretching across between the two crura of the subcutaneous inguinal ring, and they are much thicker and stronger at the inferior crus, where they are connected to the inguinal ligament, than superiorly, where they are inserted into the linea alba.
The inguinal ligament is a band running from the pubic tubercle to the anterior superior iliac spine. It forms the base of the inguinal canal through which an indirect inguinal hernia may develop.
The white line is a fibrous structure that runs down the midline of the abdomen in humans and other vertebrates. In humans linea alba runs from the xiphoid process to the pubic symphysis. The name means white line and the linea alba is indeed white, being composed mostly of collagen connective tissue.
The intercrural fibers increase the strength of the lower part of the aponeurosis, and prevent the divergence of the crura from one another; they are more strongly developed in the male than in the female.
A male (♂) organism is the physiological sex that produces sperm. Each spermatozoon can fuse with a larger female gamete, or ovum, in the process of fertilization. A male cannot reproduce sexually without access to at least one ovum from a female, but some organisms can reproduce both sexually and asexually. Most male mammals, including male humans, have a Y chromosome, which codes for the production of larger amounts of testosterone to develop male reproductive organs. Not all species share a common sex-determination system. In most animals, including humans, sex is determined genetically, but in some species it can be determined due to social, environmental, or other factors. For example, Cymothoa exigua changes sex depending on the number of females present in the vicinity.
Female (♀) is the sex of an organism, or a part of an organism, that produces non-mobile ova. Barring rare medical conditions, most female mammals, including female humans, have two X chromosomes. Female characteristics vary between different species with some species containing more well defined female characteristics. Both genetics and environment shape the prenatal development of a female.
