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1. Anatomy of abdomen and pelvis
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2. Orientation of the Abdomen and pelvis
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POSTERIOR ABDOMINAL MUSCLES

4. ANTERIOR ABDOMINAL MUSCLES
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5. ANTERIOR ABDOMINAL WALL
• Rectus abdominis run to the lower ribs and xyphoid
process from pupic bone . There Is a pair each on either
side of the linea alba(a tendinous cord from xyphoid
process to pubic sympisis.
• External oblique runs inferiorly and medially from the
lower ribs to illiac crest and by apunorosis to the linea alba.
• Internal oblique runs superiorly and medially from illiac
crest and spinous proccess of lumber vertebra to the lower
ribs.
• Transversus abdominis runs from illiac crest and lumber
vertabra transversally to insert on the linea alba .
• They compress abdominal organs , flex and rotate lumber
vertabra.
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6. Posterior abdominal wall
• Quadratus lumborum runs from illiac crest to
insert on 12th rib.
• The Psoas(from lumber vertabra) and
illicus(from illiac bone) muscle are found
deep in the wall and they act in flexion at hip
joint.
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7. The bony pelvis
 Pelvic girdle
– Two hips bones
– Each hip bone is formed by:
(1) Ilium
(2) Ischium
(3) Pubis
– Pubic symphysis joins
both pubic bones
 Sacrum (4)
 Coccyx (5)
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2
3
4
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Symphysis pubis
Basin-shaped ring of bones
The bony pelvis is composed of:

8. landmarks
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Sacral
Promontory
Subpubic Angle

9. 1. Sacrospinous lig.
sacrum to ischial spine
2. Sacrotuberous
ligament
sacrum to ischial
tuberosity
3. Obturator
membrane
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2
1
3

10. Sciatic foramina
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1. Greater Sciatic
foramen
2. Lesser Sciatic
foramen

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The pelvis is divided into two
parts by the pelvic brim.
Above the brim is the False
or greater pelvis, which is
part of the abdominal cavity.
Below the brim is the True or
lesser pelvis.
The False pelvis is bounded by:
Posteriorly:
Lumbar vertebrae.
Laterally:
Iliac fossae and the iliacus.
Anteriorly:
Lower part of the anterior
abdominal wall.
It supports the abdominal
contents.
Pelvic
brim

12. Pelvic cavity
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 Major (greater or false) pelvis
 Superior pelvic aperture
or pelvic inlet or [pelvic
brim]
 Minor (lesser, true) pelvis
 Inferior pelvic aperture or
pelvic outlet

13. Shape: Oval or circular.
Anteriorly: Symphysis pubis.
Posteriorly: Sacral promontory, ala of
sacrum.
Laterally: Ileopectineal (arcuate) lines.
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Shape: Diamond
Anteriorly: Symphysis pubis.
Posteriorly : Coccyx,
Anterolaterally: ischiopubic ramus
Posterolaterally: Sacrotuberous
ligament,
PELVIC OUTLET
PELVIC INLET

14. In general the female Sacrum is usually wider in proportion to
its length, and it is less curved.
Also, the Angle of the pubic arch is wider.
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MALE
FEMALE

15. 15
Moore, page 362
African/American females Caucasian females
41% - 41%
16% - 33% 41% - 24%
2% - 2%

16. • Transverse diameter
• widest part of inlet
• radiograph/pelvic exam and location of spines)
• Conjugate diameter
• sacral promontory to symphysis 16

17.  Obstetric (true)
conjugate
A-P diameter from sacral promontory to
upper border of pubis
Estimated by subtracting 1.5 to 2cm from
the diagonal conjugate
 Diagonal conjugate
A-P diameter from sacral promontory to
inferior border of symphysis pubis (13
– 1.5 = 11.5 cm)
Adequate if ≥ 11.5 cm
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18. It is large and formed by sacrum, coccyx , piriformis muscles and their
covering of parietal pelvic fascia.
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POSTERIOR PELVIC WALL

19. • Origin: Front of the middle 3 sacral vertebrae.
• It leaves the pelvis through the greater sciatic foramen.
• Insertion: Greater trochanter of the femur.
• Action: Lateral rotator of the femur at the hip joint.
• Nerve supply: Sacral plexus.
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Piriformis

20. It is formed by:
1- Part of the hip bone below the pelvic inlet,
2- Obturator internus and its covering fascia & the obturator membrane,
3- Sacrotuberous&
4- Sacrospinous ligaments.
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LATERAL PELVIC WALL

21. • The pelvic floor supports the pelvic viscera and is formed by the pelvic
diaphragm.
• It stretches across the true pelvis and divides it into:
• Main pelvic cavity above, which contains the pelvic viscera, and
Perineum below which carries the external genital organs.
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INFERIOR PELVIC WALL, OR PELVIC FLOOR

22. It is incomplete
anteriorly to allow
passage of the urethra
in males and the
urethra and the vagina
in females.
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It is formed by the
levator ani and the
coccygeus muscles
and their covering
fasciae.
PELVIC DIAPHRAGM

23. Actions of levator ani:
1. The muscles of the two sides form an efficient muscular sling that supports
and maintains the pelvic viscera in position.
2. They resist the rise in intra pelvic pressure during the straining and expulsive
efforts of the abdominal muscles (as in coughing).
3. They also have an important sphincter action on the anorectal junction.
4. They serve as a vaginal sphincter in the female.
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24. • Origin:
• Ischial spine.
• Insertion:
• Lower end of sacrum and
coccyx.
• Action:
• It assists the levator ani in
supporting the pelvic
viscera.
• Nerve supply:
• Fourth and fifth sacral
nerves.
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coccygeus
Coccygeus Muscle

25. Pelvic Floor – Clinical Correlations
 During childbirth the
pubococcygeus m (main
part of levator ani) is usually
torn
• Weakening of the levator ani
• May alter position of the
neck of the bladder and the
urethra
• May cause urinary stress
incontinence
 Dribbling of urine when intra-abdominal
pressure is raised.
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