Arcuate line of rectus sheath
The arcuate line of rectus sheath (the arcuate line or the semicircular line of Douglas) is a line of demarcation corresponding to the free inferior margin of the posterior layer of the rectus sheath inferior to which only the anterior layer of the rectus sheath is present and the rectus abdominis muscle is therefore in direct contact with the transversalis fascia. The arcuate line is concave inferior-wards.
| Arcuate line of rectus sheath | |
|---|---|
The interfoveolar ligament, seen from in front. (Linea semicircularis labeled at center top.) | |
| Details | |
| Identifiers | |
| Latin | linea arcuata vaginae musculi recti abdominis |
| TA98 | A04.5.01.006 |
| TA2 | 2362 |
| FMA | 16919 |
| Anatomical terminology | |
The arcuate line is visible upon the inner surface of the abdominal wall. The arcuate line may be a well-defined, or may be represented by a gradual waning of the aponeurotic fibres with concomitant increasing prominence of the transversalis fascia. The arcuate line occurs about midway between the umbilicus and pubic symphysis, however, this varies from person to person.
The inferior epigastric artery and vein pass across the arcuate line to enter the rectus sheath.