Bony skeleton in the abdomen
▪ The abdominal viscera are partially protected by bone elements:
➢ Ribs
➢ Vertebrae
➢ Pelvis
Bony pelvis
➢ With the participation of the sacrum & coccyx (parts of the vertebrae) and the two hip bones are formed
That connected together by the following
joints: sacroiliac, symphysis pubis, &
sacrococcygeal
▪ The hip bone consists of three parts:
Ilium, Pubis and Ischium
There are so-called small and large pelvis
1. The greater upper cavity, called the
greater pelvis, is part of the abdominal cavity.
2. The lesser lower part is called the true pelvis
Between the two cavities is the inlet
The dimensions of the inlet, outlet and the
true pelvic cavity are especially important
in pregnancy and childbirth
Hip bone
➢ Innominate bone, coxae are its other names
It is rectangular and irregular
Its middle part is narrow while upper part is wider
It contains an oval foramen called an obturator
It has two external and internal surfaces and
Four superior, inferior, anterior and posterior borders
The outer surface has a small fossa called the acetabulum, which is where the femur articulates
The two bones in the front are articulated together (symphysis pubis)
▪ The pelvis is made up of three embryonic parts that are fused together:
1. Ilium
2. Pubis
3. ischium
Hip borders
▪ The hip bone has four borders:
I. Upper border: Named the iliac crest, that extends from the anterior iliac spine (asis) to the upper posterior iliac spine & has two parts: abdominal and dorsal
II. Anterior border: that extends from asis to upper side of symphysis pubis and includes ant. Inf. iliac spine, iliopubic eminentia, pectineal line, pubic tubercle and
pubis crest
III. Inferior border: extends from the upper side of the symphysis pubis to ischial and includes ischiopubic ramus and ischial tuberosity 17
IV. Posterior border: including ischial tuberosity, small sciatic notch, sciatic spine, greater sciatic notch, inf. Post. iliac spine to upper posterior iliac spine
Pelvic Inlet
▪ It is located between greater and lesser
pelvis and consists of terminal lines on
both sides
➢ The terminal line consists of:
1. Promontory (upper border of sacrum)
2. Sacrum wing
3. Arcuate line or semilunar line
4. Iliopubic eminence (a bulge between
the ilium and pubis, where the ilium and
pubis fuse)
5. Pectineal line or shoulder line (pubis)
6. Pubic tubercle (belongs to pubis bone)
7. Pubic Crest (Pubis)
8. Upper edge of pubic symphysis (pubis)
