Also called saphenous vein hiatus.yesFascia lataThe oval depression formed is located about 2.5cm below the middle 1/3 junction in the inguinal ligament.It is about 4cm long and 2.5cm wide.Its outer edge is sharp and called sickle edge, which is close to the anterior wall of the femoral sheath;The outer edge bent upward is called the upper angle;The lower horn passes through the great saphenous vein and continues to the fascia of the pubic muscle.The inner edge of the fossa is not obvious.The fascia in the oval fossa area is weak and has many small holes through which veins and lymphatic vessels pass. It is called ethmoidal fascia.
The oval fossa, also known as the greater saphenous foramen, is covered withFascia lataThe latter has many small blood vessels andlymph glandIt runs through the cribriform, also called cribriform fascia.The outer edge of the hole is sharp, which is called sickle edge. It is located in front of the femoral sheath. The inner edge is composed of the deep layer of the fascia lata, that is, the fascia of the pubis muscle. It is not very clear. From the outside to the femoral sheath, the upper and lower corners of the sickle edge are respectively in the front and back of the end of the great saphenous vein. The upper corner extends to the pubic tubercle, connecting with the inguinal groove ligament and the lacunar ligament, and the lower corner continues to be the fascia of the pubis muscle.The great saphenous vein flows into the lower cornerfemoral veinAnd sometimes injected at 1~2cm above it.Oval fossa is generally oval, but can be round or very narrow, such as a crack, or sometimes shield shaped, with the tip downward.Looking forGreat saphenous veinandfemoral veinThis variation must be noted.The position of the oval fossa is relatively constant, and its inner and upper corners are 0~4cm (average 1.5 cm) below the pubic tubercle and 2~6cm (average 2.5 cm) outside.Its size also has many variations, the smallest is 1.0 cm long and 1.7 cm wide;The largest is 8.5cm long and 3.5cm wide.In terms of length, 90% is 3.0~6.4 cm;Average 4.6cm;In terms of width, 87% is 1.5~3.9cm, with an average of 2.8cm.
Oval fossa is one of the most common sites of atrial septal defect.The septal tissue separating the left and right atria.It is also called septum interatrial.After birth, due to the increased pressure in the left atrium, the first atrial septum is compressed to gradually heal with the second atrial septum, forming a permanent atrial septum.The foramen of the second chamber gradually closed to form a fossa ovalis.The atrial septum is thin, and its position is about 45 ° to the midsagittal plane.In addition to two layers of endocardium, the atrial septum is composed of a layer of connective tissue and some muscle bundles.The room is about 4mm thick.The oval fossa is located in the lower 1/3 of the atrial septum, the upper left of the inferior vena cava orifice, the long axis is vertical, and the center of the oval fossa is only 1mm thick.Its right side is concave and its left side slightly protrudes out of the left atrial cavity.There is a small groove with a depth of 3-4 mm in the central depression, and about 30% of people have a small hole to access the left atrium.The slightly raised front upper edge of the oval fossa is the oval fossa edge, which is the vestige of the fetal period.Oval fossa is one of the most common sites of atrial septal defect.
