A fascia is a band of connective tissue located beneath the skin, which encloses and separates muscles. There are two main types of fascia: superficial and deep. The deep fascia of the thigh is referred to as the fascia lata.
The fascia lata is split into two layers, which are referred to as the superficial stratum and the deep stratum.
There are three modifications of the fascia lata, one of which is the saphenous opening. The saphenous opening is an oval aperture located in the fascia lata to allow the passage of the great saphenous vein. This article will discuss the anatomy of this structure followed by any relevant clinical notes on the topic.
The saphenous opening is located inferolateral to the medial aspect of the inguinal ligament and is usually approximately 3.75 cm in length and 2.5 cm wide, but can vary considerably. The centre of the opening is 3-4 cm lateral to the pubic tubercle. The cribriform fascia, a sieve-like membranous layer of cutaneous tissue, covers the opening and is thus pierced by the great saphenous vein.
The superficial stratum is located superolateral to the saphenous opening and is continuously attached to the:
- pectin pubis
- the lacunar ligament
- the inguinal ligament
- the anterior superior iliac spine
- the iliac crest
The superficial stratum reflects inferolaterally from the pubic tubercle to form the arched falciform margin. This margin forms the superior, inferior and lateral boundaries of the saphenous opening. The deep stratum is located medial to the saphenous opening.
A femoral hernia is a protrusion of an intra-abdominal organ, such as the stomach or small intestine, through the femoral ring, femoral canal and the saphenous opening. It is more common in females than males and can be caused by an increase in abdominal pressure from pregnancy, bronchitis and constipation. The increase in pressure can dilate the femoral vein, which in turn stretches the femoral ring, allowing part of the organ to pass through the femoral canal before exiting via the saphenous opening. Symptoms can include:
- presence of a lump in the groin
- colicky pain
Strangulation occurs when the blood supply to the organ is compromised and can lead to ischaemia of that part of the organ, which can result in necrosis. When this occurs, it is life-threatening and surgery must be carried out in order to repair the hernia.