Structure
The obturator membrane is oval or irregularly triangular, following the shape of the obturator foramen. It is made up of strong interlacing transverse fibers. The obturator membrane has a gap or opening at its superolateral surface, along with the obturator groove on the pubis, called the obturator canal.
Anatomical Relations
The obturator membrane is a thin but strong fibrous aponeurosis that closes the obturator foramen. It is attached to the margins of the obturator foramen, and to the ischial ramus inferolaterally. The obturator nerve, vein, and artery exit the pelvis through the obturator canal, an opening on the superolateral surface of the membrane. The obturator artery divides into its anterior and posterior branches which run along the margins of the obturator foramen and lie between the obturator membrane and obturator externus muscle. Fibers from the pubofemoral ligament of the hip joint are attached to its outer surface.
Function
The obturator membrane provides an extensive surface area for muscle attachment. The obturator externus lies on its anterior surface and obturator internus on its pelvic/inner surface. The obturator canal serves as a passageway for vessels traveling from the pelvis to the medial thigh.
List of Clinical Correlates
—Obturator sling procedures to manage urinary incontinence
