Now we’ll look at the spermatic cord. In the developing embryo, the migrating testis pushes its way through the abdominal wall, and into the scrotum, creating the inguinal canal as it does so. The testis drags behind itself its own blood vessels and the vas deferens; and it carries along as a covering, a little of each layer that it goes through. To see the result, we’ll look at a dissection in which the spermatic cord has been kept intact.
Here’s the spermatic cord,with its outer layers removed. To see the structures that run inside the cord, we’ll go round to a rear view again. The deep inguinal ring is here, hidden by the transversalis fascia. The iliacus fascia has been removed.
The structures that pass through the deep inguinal ring and into the spermatic cord are the blood vessels to the testis, the testicular artery and vein, and the vas deferens, which passes over the pelvic brim and into the pelvis.
Emerging from beneath transversus, the vas deferens and the blood vessels are surrounded by this coating of internal spermatic fascia. Now we’ll add the internal oblique muscle.
The internal spermatic fascia is surrounded, by this layer of muscle, the cremaster muscle. Here’s the cut edge of the external oblique aponeurosis. We’ll add the rest of the external oblique aponeurosis to the picture.
As the cord emerges from the superficial inguinal ring, it lies in front of the pubic tubercle, here. This edge of the superficial ring is a dissection artifact. In reality it’s continuous with the outermost layer of the spermatic cord, the external spermatic fascia. From here, the spermatic cord goes down into the scrotum.
We’ll look at the testis in Volume Five of this Atlas.