Fasciae of abdomen

The term fasciae of abdomen (previously "fascia of abdomen" in the Terminologia Anatomica 1) groups the different fasciae that covers the abdominal wall into the abdominal cavity.

The term fasciae of abdomen remains unclear and widely discussed by different authors but in the Terminologia Anatomica 2, the term " fasciae of abdomen" comprises:

• The investing abdominal fascia that envelops the external and internal oblique muscles and the transversus abdominis. The investing abdominal fascia was previously ivided into three layers into the Terminologia Anatomica 1 and source of confusion (these layers are not officialy listed anymore in Terminologia Anatomica 2):

  • The superficial investing abdominal fascia that covers the external surface of external oblique muscle and forms the suspensory ligament of clitoris/ penis. Some sources called this superficial investing abdominal fascia with the eponym "Gallaudet's fascia", but this eponym is already used for the perineal fascia, which is confusing.

  • The intermediate investing abdominal fascia that covers the internal oblique muscle: it is composed by two layers of fascia, one internal and one external to the internal oblique muscle. The internal layer is formed by the fascia investing the external surface of the transversalis muscle and the fascia covering the internal surface of the internal oblique muscle (the two fasciae coalesce.) The external layer is given from the fasciae investing the external surface of the internal oblique and the internal surface of the external oblique muscle.

  • The deep investing abdominal fascia that covers the transversalis muscle: for some authors, the deep investing abdominal fascia and the fascia transversalis are the same structures (Transversalis fascia is the inner epimysium of transversus abdominis muscle; no separate deep investing fascia exists).

• The endoabdominal fascia, that comprises:

  • The transversalis fascia, with its regional condensations (deep inguinal ring, interfoveolar ligament, iliopubic tract, umbilical fascia). The transversalis fascia is the innermost layer of the endoabdominal (parietal abdominal) fascia, and consequently is not synonymous with it.

  • The iliopsoas fascia that covers the iliac muscle (iliac fascia) and psoas muscle (psoas fascia).

  • The diaphragmatic fascia that covers the inferior surface of the diaphragm, and is continuous inferiorly with the transversalis fascia and the iliopsoas fascia.

Note --------------------

• The term fasciae of abdomen does not concern the visceral fasciae (fasciae of organs)

• For some authors, the endoabdominal fascia may be the fascia that only covers the abdominal cavity, or a generic term including extraperitoneal and visceral fasciae.

• The term "superficial fascia of abdomen" may not be used anymore (and do not belong to the fasciae of abdomen). Previously (in Gray's for example), the superficial fascia of abdomen was describded as a fascia, and near the groin was divided into a superficial and a deep layer (that are not anymore considered as fasciae in the Terminologia Anatomica 2):

  • The "superficial layer of the superficial fascia of abdomen" (Fascia of Camper:) the tela subcutanea of the anterior abdominal wall that si now termed as panniculus adiposus abdominis. Previously described as the superficial layer of the superficial fascia of abdomen.

  • The "deep layer of the superficial fascia of abdomen" (Fascia of Scarpa) now termed as membranous layer of abdominal subcutaneous tissue.