PELVIS MUSCULATURE
PELVIC MUSCULATURE:
The pelvic muscles of importance in gynaecology are those of the pelvic floor grouped into three layers:
| LAYER | MUSCLE |
| Pelvic Diaphragm | 2 levator ani muscles
Obturator internus
Puborectalis
|
| Urogenital Diaphragm | Sphincter urethra
Deep transverse Perineal Compressor urethra |
| Superficial Layer | Superficial transverse Perineal
Ischiocavernous bulbospongiosus The external |
| Muscle | Origin | Insertion |
| Pubococcygeus | Post. Pubic bone | Anococcygeal raphe and coccyx |
| Iliococcygeus | white line of the pelvic fascia | coccyx. |
| Ischiococcygeus | ischial spine | coccyx |
| Obturator internus | Pelvic aspect of ischium & ilium
Obturator membrane |
Greater trochantor of femur |
| Puborectalis | Posterior surface of pubis | Midline sling posterior to rectum |
| Sphincter urethra | Circular anatomical sphincter | Fuses with deep transverse perinei |
| Compressor urethra | ischiopubic ramus | Blends with its partner on the other side
anterior to urethra below external urethral sphincter |
| Superficial transverse Perineal | Ischial tuberosity | Perineal body |
| Ischiocavernous | Ischial tuberosity | Clitoris |
| bulbospongiosus | Central point of perineum | symphysis pubis |
| Deep transverse Perineal | Ramus of ischium | Perineal body |
| The external sphincter muscle of the anus |
Central point of the perineum | Surrounds the anus |
ACTION OF MUSCLES:
The roles of the pelvic floor muscles are:
- Support of abdominopelvic viscera (bladder, intestines, uterus etc.) through their tonic contraction.
- Resistance to increases in intra-pelvic/abdominal pressure during activities such as coughing or lifting heavy objects.
- Urinary and fecal continence.The muscle fibers have a sphincter action on the rectum and urethra. They relax to allow urination and defecation.Puborectalis is essential to maintain continence
Exam Important
- Muscles that can cause external rotation of the hip include Obturator internus
- Pubovaginalis, External urethral sphincter & Bulbospongiosus are sphincters of lower genito urinary tract of female
- Pelvic diaphragm is formed by Pubococcygeus,Iliococcygeus & Pubovaginalis
- Urogenital Diaphragm is made up of Sphincter urethrae , Perineal membrane & Deep transverse Perineal muscle
- Superficial perineal muscles include Bulbospongiosus
- Lateral border of ischeorectal fossa is formed by Obturator internus
- Puborectalis is essential to maintain continence
- Sphincter urethrae is Voluntary, Arises from ischiopubic ramus and are Supplied by pudendal nerve
- Pubococcygeus supports prostate
Don’t Forget to Solve all the previous Year Question asked on PELVIS MUSCULATURE
