Male pelvis | Museum of Anatomy and Pathology, Manipal Academy of Higher Education, Manipal

≪

Details

Male pelvis

This specimen shows the sagittal section of the male pelvis.

The male pelvis consists of organs such as the urinary bladder, the urethra, the prostate, the rectum and the anal canal. Other structures such as the seminal vesicles, the ejaculatory ducts, the terminal parts of the vas deferens, the distal parts of the ureters along with the blood vessels and the nerves are also present within the pelvis.

Urinary bladder:

The urinary bladder is a muscular bag that temporarily stores urine. It is located in the lesser pelvis behind the pubic symphysis. An empty urinary bladder is tetrahedral in shape. The ureters open into the posterior aspect of the urinary bladder. The neck of the urinary bladder is directed downwards and becomes continuous with the urethra at the internal urethral orifice. In males, the prostate gland is situated onto the urethra and the neck of the urinary bladder. In case of benign prostatic hypertrophy, the median lobe of prostate enlarges producing an elevation within the urinary bladder known as uvula vesicae. This uvula vesicae obliterates the internal urethral orifice, thereby making the passage of urine more difficult.

Prostate:

The prostate is a pyramidal fibromuscular gland which surrounds the prostatic urethra from the base of the urinary bladder to the membranous urethra. The gland presents numerous lobes. Within each lobe, there are numerous secretory acini. As age advances, these secretions could get calcified to form the prostatic concretions. In case of benign prostatic hypertrophy, the median lobe of prostate enlarges producing an elevation within the urinary bladder known as uvula vesicae. This uvula vesicae obliterates the internal urethral orifice, thereby making the passage of urine more difficult.

Rectum:

The rectum is the terminal portion of the gastrointestinal tract. In males, it is related to the urinary bladder and the prostate anteriorly and to the sacrum and coccyx posteriorly. It is very prone for hemorrhoids.

Anal canal:

The anal canal is the terminal part of the gastrointestinal tract. It is 3.8 centimeters long. The anal canal is more prone for hemorrhoids.

Content partner

Voiceover

The urinary bladder is a reservoir. Its size, shape, position and relations all vary according to its content and the state of neighbouring viscera. When the bladder is empty, it lies entirely in the lesser pelvis, but as it distends it expands anterosuperiorly into the abdominal cavity. An empty bladder is somewhat tetrahedral and has a base (fundus), neck, apex, a superior and two inferolateral surfaces.

The base of the bladder is triangular and located posteroinferiorly. In females it is closely related to the anterior vaginal wall. In males it is related to the rectum although it is separated from it above by the rectovesical pouch, and below by the seminal vesicle and vas deferens on each side and Denonvillier's fascia. The neck, which is most fixed, lies most inferiorly, 3–4 cm behind the lower part of the symphysis pubis and just above the plane of the inferior aperture of the lesser pelvis. The bladder neck is essentially the internal urethral orifice, which lies in a constant position, independent of the varying positions of the bladder and rectum. In males the neck rests on, and is in direct continuity with, the base of the prostate.

The vas deferens is the distal continuation of the epididymis, starting as a muscular tube at the epididymal tail. It is 45 cm long and conveys sperm to the ejaculatory ducts. From the superior pole of the testis it ascends in the posterior part of the spermatic cord, and traverses the inguinal canal. At the deep inguinal ring the vas deferens leaves the cord, curves round the lateral side of the inferior epigastric artery and ascends for approximately 2.5 cm anterior to the external iliac artery. It crosses the ureter and bends acutely to pass anteromedially between the posterior surface of the bladder and the upper pole of the seminal vesicle. It then descends in contact with the seminal vesicle, gradually approaching the opposite duct, lying between the base of the bladder and the rectum, from which it is separated by Denonvillier's fascia. At the base of the prostate, the vas deferens joins the duct of the seminal vesicle at an acute angle to form the ejaculatory duct.

The two seminal vesicles are sacculated, contorted tubes located between the bladder and rectum. Each vesicle is approximately 5 cm long, somewhat pyramidal, the base being directed up and posterolaterally. In essence, the seminal vesicle is a single coiled tube with irregular diverticula, the coils and diverticula being connected by fibrous tissue. On each side they are related to the vas deferens and the termination of the ureter, and they are partly covered by peritoneum. Each has a dense, fibromuscular sheath. The paired seminal vesicles, together with the ampulla of the vas deferens and the ejaculatory ducts, form a functional unit which develops slowly until the onset of puberty. After puberty the vesicles form sac-like structures which contribute up to 85% of the seminal fluid.

The prostate is a pyramidal fibromuscular gland which surrounds the prostatic urethra from the bladder base to the membranous urethra. It has no true fibrous capsule, but is enclosed by visceral fascia containing neurovascular tissue. The fascia is firmly adherent to the gland and is continuous with a median septum and with numerous fibromuscular septa which divide the glandular tissue into indistinct lobules.

Features

Prostate (PRS)

View

Urinary Bladder (UB)

View

Rectum (REC)

View

Anal Canal (ANC)

View

Male pelvis

© Manipal Academy of Higher Education. All rights reserved.

Disclaimer

Manipal Academy of Higher Education retain their full rights to any content they upload to this website, including, but not limited to, images, videos, biographies and business information. All other content on this website, including but not limited to text, graphics, logos, icons, images, audio clips, video clips, digital downloads, data compilations, and software, as well as any compilation consisting of the selection, organization, or arrangement of content on this website, is the property of Manipal Academy of Higher Education and no portion of such other content may be reprinted, republished, modified, or distributed in any form without the express written permission of Manipal Academy of Higher Education