Anatomy
The spermatic duct (lat. Ductus deferens) represents a 35-40 cm long tube, which is characterized by a thick muscle layer. The smooth musculature, which ensures optimal forward transport of the sperm, is divided into three layers.
Thus one distinguishes an inner longitudinal layer, a middle ring layer and the outer longitudinal layer of the muscles. The spermatic duct is surrounded by blood and lymph vessels of the testes as well as muscle and nerve fibers, which entwine and wrap themselves around it like a network. The entirety of all structures is called the spermatic cord.
The vas deferens uses various body structures of its own as a guide from the epididymis to the spermatic duct (Latin: Ductus ejaculatorius). It begins at the terminal part of the epididymis. The epididymis lies on top of the testis so that men can feel the beginning of the spermatic cord above the testis themselves.
It is comparable in consistency and shape to a “hard-boiled spaghetti”, but cannot be followed further in the direction of the groin. The spermatic cord then passes through the inguinal canal; this provides protection against excessive bending. The vas deferens first runs laterally outwards towards the flank and then towards the bladder.
It crosses both blood vessels and the ureter to reach the prostate. Here it forms the spermatic duct with the outlet duct of the seminal vesicle, another male sex gland. This channel leads through the prostate and flows into the urethra.
Function of the vas deferens
The function of the vas deferens is to transport the sperm from their place of production, the epididymis, to the injection channel during ejaculation. Sperm transport is achieved by rhythmically tensing and relaxing individual sections of the spermatic duct muscles. This wave-like movement causes the seminal fluid to enter the outlet of the spermatic duct.
The starting signal for the muscle activity is given by nerves that belong to the sympathetic nervous system and thus an independent part of our nervous system. The increasing mechanical stimulation from outside leads to the activation of these nerve fibers, which in turn causes the contraction of the smooth muscles in the vas deferens. An inflammation of the vas deferens is usually the result of an ascending infection starting from the urethra or an inflammation spreading from the prostate gland due to its anatomical proximity.
The inflammation causes swelling of the soft tissues of the vas deferens; nerve fibers are excessively sensitized. As a result, the inflammatory process can spread along the vas deferens to the testicles, where it can manifest itself as testicular inflammation. The symptoms of an inflammation of the sperm duct vary greatly and range from pain to swollen lymph nodes in the groin to an elevated body temperature.
Since the muscles of the spermatic duct are tense, especially during ejaculation, pain or an unpleasant pulling sensation during orgasm can occur. Pulling in the testicles The cause of the inflammation is usually intestinal bacteria which, due to inadequate genital hygiene, enter the urethra and rise from there to the vas deferens. The mucous membrane of the urogenital organs forms a good breeding ground for the bacteria, as it is moist and warm due to the good blood circulation.
However, bacteria that are transmitted in the context of sexually transmitted diseases can also cause an inflammation of the vas deferens. Therefore, an infection with Chlamydia or the causative agent of syphilis through unprotected sexual intercourse must always be ruled out. In general, isolated inflammation of the spermatic duct is extremely unlikely.
For this reason, the trigger should always be sought, which can lie either before or after the spermatic duct. If the vas deferens is swollen, this can have two primary causes. On the one hand, it may be thickened by fluid retention during an inflammation, on the other hand, it may appear swollen due to an inflammation of the surrounding structures.
For example, there may be an accumulation of fluid in the scrotum, a so-called hydrocele. In reality, it is not always possible to distinguish clearly whether closely adjacent structures are affected by a pathological process in isolation or whether it affects several structures. Since the sperm duct runs in the spermatic cord and is surrounded by muscles, blood vessels, nerves and connective tissue, the doctor always assesses the totality of all the structures mentioned.
This explains why the symptoms and their respective localization are decisive for routine diagnostics. The symptomatology is the same as for an inflammation of the spermatic duct and can be more or less intense depending on the degree of swelling.If the inner cavity of the spermatic duct is constricted, the sperm concentration in the ejaculate may be reduced, resulting in infertility. If the vas deferens is blocked, no more sperm can reach the injection channel from the epididymis, so that a blocked vas deferens duct clinically manifests itself as male infertility.
An isolated blockage of the vas deferens is not painful and does not lead to functional abnormalities regarding the man’s sexuality. It is a purely mechanical obstacle that hinders the transport of sperm. Only when the injection channel is blocked, i.e. when the vas deferens is connected to the outlet of the vesical gland, does the ejaculate accumulate.
This congestion of seminal fluid directly before it enters the urethra can cause pain in the area of the pelvis. These usually occur shortly after orgasm, but can also manifest themselves as chronic pain in the lower pelvis. If the testicle rotates around the spermatic cord, this is called testicular torsion.
This twisting causes blood vessels to bend, which supply both the testicle and the spermatic cord. The reduced blood flow is usually manifested by severe pain. This pain should be perceived as an absolute warning signal, since tissue damage to the testicle can occur within a short time.
Due to its position in the scrotum, it has only a limited supply of blood vessels, which cannot be compensated for in any other way. As a reaction to the reduced supply, the testicle swells and can take on a deep red to purple-blue color depending on the degree of torsion. Any movement or manipulation of the testis is painful and cannot be improved by changing the position of the testis.
Any twisting of the spermatic cord must be corrected promptly by surgery. The structures are untwisted again and fixed, so that a renewed torsion of the testicle is prevented. Nodular changes in the vas deferens and spermatic cord can have various causes.
One of these causes are so-called sperm granulomas. These form when sperm reach the surrounding tissue as a result of injuries in the sperm duct, e.g. during a vasectomy. The body reacts to the cells recognized as foreign in this environment and an inflammatory reaction occurs.
A granuloma is ultimately the aggregation of inflammatory cells around the sperm and the body’s attempt to encapsulate the cells from the surrounding tissue and then break them down. Sperm granulomas usually regress after some time, but in some cases surgical removal may be necessary. A further cause of palpable nodules can be calcifications in the spermatic duct, which can develop in the course of tuberculosis disease.
In the groin area there are also a number of lymph nodes, which are enlarged and palpable from the outside, e.g. in the case of inflammation. These can be misinterpreted as nodes of the spermatic cord or vas deferens. A vasectomy is the cutting or ligation of the vas deferens during surgery.
The aim of this operation is to achieve male infertility. The sole aim is to prevent sperm from escaping during ejaculation without making any other functional changes. After the surgical procedure, erection and ejaculation are still possible.
The ejaculate is unchanged in quantity and consistency; it differs from the previous ejaculate only in the missing sperm. It is important to know that after the surgery, the man has the same ability to experience orgasm as before and his sexuality is not affected. The production of the hormone testosterone is also unchanged, so there are no hormonal fluctuations after the operation.
The vasectomy does not cause any noticeable physical changes visible from the outside. Only small scars through the incisions in the scrotum can be seen. Compared to other contraceptive methods, cutting the vas deferens is a very safe method of contraception, as the Pearl Index proves.
The Pearl index is a parameter that indicates the reliability of a contraceptive method. It indicates how many out of every hundred women become pregnant per year despite using a contraceptive method. The smaller the Pearl index, the safer the contraceptive method.
A vasectomy has a Pearl Index of almost zero and is therefore safer than the contraceptive pill for women, for example. Are you also interested in other contraceptive methods? One disadvantage of this contraceptive method for men is that although it is possible to reverse the procedure (refertilization), success is not guaranteed.Therefore, family planning should certainly be completed before a man decides to take this step.
Last but not least, the man should be aware that this operation is not covered by the statutory health insurance if there is no medical necessity, but is a self-paying health service. A disadvantage of this method of contraception for the man is that although it is possible to reverse the procedure (refertilization), success is not guaranteed. Therefore, family planning should be completed before a man decides to take this step.
Last but not least, the man should be aware that this operation is not covered by the statutory health insurance if there is no medical necessity, but is a self-paying health service. A vas deferens valve is a new method of contraception. When closed, the valve prevents the sperm from being transported from the testicles via the sperm duct into the urethra and thus into the ejaculate.
This means that during an orgasm, ejaculation still occurs, but it does not contain any sperm, which rules out fertilisation and pregnancy. The device is implanted in the vas deferens on each side of the urethra in a local anesthetic operation. There are no known effects on libido or other side effects, but as with any operation, there are certain risks such as bleeding or infection.