MORPHOLOGY OF THE MALE PELVIC AND UROGENITAL DIAPHRAGMS

Dr. Andrea D. Székely

Semmelweis University Department of Anatomy, Histology and Embryology Budapest FUNCTIONS AND ROLES OF THE PELVIC FLOOR

• It makes a fundamental contribution to movement and stability • Functions in coordination with the abdominal, back, and hip muscles • Especially important is its relationship to the Transversus Abdominis (the deepest layer of the abdominal muscles), and the Multifidus muscles in the low back, to maintain the integrity of pelvic, sacral, and spinal joints during movement • It supports the prostate, bladder, rectum, and seminal vesicles • It regulates continence, opening and closing the urethra and anus as needed • It plays an essential role in sexual function • It acts reciprocally with the respiratory diaphragm in breathing. • It is a flexor of the coccyx (tail bone) • The pelvic floor is the center of gravity in your frame, the place where movement is initiated, and is essential to your overall sense of well- being. BONY AND LIGAMENTOUS FRAMEWORK PERINEUM EXTERNAL GENITALS Surface features Homologous organs PERINEUM Surface regions

UROGENITAL TRIANGLE

ANAL TRIANGLE MORPHOLOGICAL DIMORPHISM Male and female perineal muscles PERINEAL LAYERS OF MUSCLES AND FASCIAE MUSCLE LAYERS OF THE PELVIC FLOOR

1. Pelvic diaphragm : 2. Urogenital Diaphragm : levator ani and the fasciae deep transverse perineal 1. (ant) pubococcygeus and the fasciae 2. pubovaginalis 1. urethrovaginal sphincter 3. puborectalis 2. compressor urethrae 4. (post) iliococcygeus 3. urethral sphincter 5. coccygeus (ischiococcygeus) External anal sphincter PERINEAL BODY

3. Urogenital trigone : - ischiocavernosus - bulbospongiosus - superficial transverse perineal m. corrugator cutis ani (smooth muscle) FASCIAL LAYERS Fascia transversalis continues as the endopelvic fascia lining the pelvic cavity

PELVIC FASCIA Lamina parietalis (obturator internus + Piriformis) Lamina visceralis (M. levator ani and M. coccygeus) =

= superior fascia of the pelvic diaphragm * surrounding the pelvic viscera)

* to be joined by the inferior fascial layer - see later PELVIC DIAPHRAGM LEVATOR ANI

M. pubococcygeus (+ rectococcygeus)

ORIGIN: Sup. Ramus of pubic bone INSERTION: Anococcygeal lig., Sacrum, Coccyx, M. sphincter ani ext.

Fibres cross in an 8 shape limiting 2 openings Urogenital Hiatus Anal Hiatus

M. iliococcygeus ORIGIN: Tendinous arch of the obturator int. + ischiac spine INSERTION: anococcygeal ligament

joined by the

M. coccygeus from posterior ORIGIN: Ischiac spine INSERTION: sacrotuberal lig., Coccyx, Sacrum)

Function: Strengthens the pelvic floor FURTHER MUSCLES AND FASCIAE OF THE PELVIC WALL

M. obturator internus Inferior fascia of the pelvic diaphragm ORIGIN: Obturator membrane + foramen covers the lower surface INSERTION: Trochanteric Fossa * Joins the superior fascial layer - see earlier Completes the lateral wall of the pelvis

The piriformis or the triceps coxae will NOT contribute to the pelvic floor or wall

Below the tendinous arch (of the levator ani) this fascia forms the lining of the isciorectal fossa together with the obturator fascia PELVIC FLOOR LAYERS, LEVATOR ANI ORIGINS AND DIVISIONS Urogenital hiatus – anal hiatus

pubococcygeus puborectalis

iliococcygeus Anococcygeal ligament

piriformis (ischio)coccygeus PERINEAL MUSCLES, UROGENITAL DIAPHRAGM

Deep transverse perineal muscle

Trapezoid in shape, pulls between the inferior rami of the pubic bones. Forms the inferior cover of the pelvic diaphragm (fused to it at the perineal body) Passes the dorsal penile nerves and vessels between the arcuate pubic lig. and the transverse pelvic lig.

Spalteholz

M. bulbospongiosus Superficial transverse M. ischiocavernosus perineal muscle ORIGIN: external anal sphincter + raphe of penile ORIGIN: ischiac tuberosity ORIGIN ischiac tuberosity INSERTION: Crus penis INSERTIONperineal body) bulb, fused to the perineal body (erection + ejaculation) + cavernous bodies (erection) PERINEAL FASCIAE AND SPACES

SUPERFICIAL PERINEAL FASCIA LAMINA SUPERFICIALIS UROGENITAL TRIGONE thick areolar CT, continues in the tunica dartos, (perineal pouch) fused to the skin in the midline superficial transverse perineal bulbospongiosus LAMINA PROFUNDA (fascia Colles) thin, fibre rich CT membrane, continues in the ischiocavernosus tunica dartos, deep penile fascia, deep spermatic fascia, covers the muscles. Fused to the superficial lamina in the midline

DEEP PERINEAL FASCIA (TRIANGULAR LIGAMENT) LAMINA INFERIOR Anteriorly - open towards the arcuate ligament, posteriorly fuses to the perineal body, covers the deep transverse perineal muscle

LAMINA SUPERIOR Continuation of the obturator fascia, anterior attm to the pubic arch, posteriorly merges with the deep lamina (ligamentum transversum pelvis) THE ISCHIORECTAL FOSSA WALLS ANTERIOR (recessus anterior) MED: levator ani LAT: obturator internus INF: deep transverse perineal

POSTERIOR MED: anal fascia, sphincter ani ext. LAT: ischiac tuberosity, obturator fascia ANT: superfic and deep perineal fasciae POST: sacrotuberal lig., gluteus maximus

CONTENT Adipose CT, containing : inferior hemorrhoidal aa., vv., nn. cutaneous br. of the pudendal plexus posterior scrotal aa., vv., nn.

Alcock’s canal : Fascial duplication of the obturator internus CONTENT pudendal n. internal pudendal a. internal pudendal v. DEEP AND SUPERFICIAL PERINEAL SPACES PELVIC CONNECTIVE TISSUE SPACES

Corning

Prevesical space (of Reitzus) Contains the prostatic venous plexus (of Santorini)

Paracysticum Retrovesical space Paraproctium Retrorectal space Contains the sup. rectal, median and lateral sacral arteries; pelvic and sacral splanchnic nerves; branches of the hypogastric & sacral plexus VASCULAR AND NERVOUS SUPPLY

Branches of the internal pudendal a./v.

Branches of the pudendal n.

PELVIC PASSAGES – THE MALE URETHRA PELVIC PASSAGES – THE ANAL SPHINCTER

Sobotta

External anal sphincter Voluntary action (striated muscle)

Pars profunda

Pars superficialis (between the perineal body and the anococcygeal ligament)

Rauber-Kopsch Pars subcutanea PELVIC PASSAGES – THE ANAL CANAL CLINICAL RELEVANCES CLINICAL RELEVANCES

ECTOPIC TESTICLE VARICOCELE HYDROCOCELE

INGUINAL CANAL CLINICAL RELEVANCES - HAEMORRHOIDS THANK YOU FOR YOUR ATTENTION!