CompAnat: Hindlimbs

Two symmetrical Hip bones

Pelvic girdle consists of

Pelvic symphysis

The two symmetrical hip bones meet ventrally at the?

Sacrum

DORSALLY, the pelvic girdle articulates with the

Sacrum, First caudal vertebra

Together, they form the bony pelvis

Bony pelvis

Encircles the pelvic cavity

Ilium, Pubis, Ischium

Each hip bone is composed of three parts with separate ossification centers:

Ilium

dorsocranial part of the hip bone and extends obliquely from the acetabulum to the sacrum

Wing, Columnar Body

Division of the ILIUM

Orientation of ilial wings

species-specific, significantly influencing the form of the pelvis.

Vertical

Ilial wings of HORSE, OX

Dorsolaterally

Ilial wings of small ruminants

Almost Sagittal

Ilial wings of PIGS and CARNIVORES

Coxal tuber

An important landmark in all domestic mammals is the

Coxal tuber

at the lateral angle of the hip, which forms the point of the hip

Horse, Ox

Coxal tuber is VISIBLE

Dog

Coxal tuber is PALPABLE

Pubis

L-shaped

Body, Transverse Acetabular Branch, Sagital symphysial branch

The pubis is composed of/

Obturator foramen

The pubis borders more than half of the

Obturator Foramen

large opening in the pelvic floor through which the obturator nerve (nervus obturatorius) passes.

Obturator Nerve

Passes through the obturator foramen

Body, Caudal Plate, Medial Branch

DIvision of ISCHIUM

Acetabulum

The body of the ischium (corpus ossis ischii) forms part of the

Ischiatic Spine

DORSAL border of the ischium

Acetabulum

deep cotyloid cavity to which all three pelvic bones contribute

Acetabuli

Additional fourth bone in the acetabulum

Carnivores

An additional fourth bone in the centre of the cavity, the small acetabular bone (os acetabuli), is present in?

Ilium, Ischium, Pubis

Composition of acetabulum based on craniolaterally, caudolaterally, medially

Craniolateral

The ilium makes up this part of the acetabulum

Caudolateral

The ischium makes up this part of the acetabulum

Medial

The pubis makes up this part of the acetabulum

Spheroidal Joint

The acetabulum is reciprocal to the head of the femur with which it forms a

Pelvis

broad ring around the pelvic cavity

Pelvis

Its conformation reflects the multiple functions

cranial pelvic aperture or inlet

bounded by the terminal line (linea terminalis).

Terminal Line

Passes along the promontory of the sacrum dorsally, the wings of the ilia laterally and ends in the pecten of the pubis ventrally.

caudal pelvic aperture or outlet

is formed by the first three or four caudal vertebrae dorsally, the ischiatic arch and the ischial tuber ventrally and the broad sacrotuberous ligament laterally.

Sacrum, dorsally; Wings of Ilia, Laterally, Pecten of Pubis, Ventrally

The terminal line passes along the promontory of the

Stringshaped

Shape of Sacrotuberous ligament in dogs

Absent

Sacrotuberous ligament in cats

floor of the pelvis

of considerable obstetric importance.

Ruminants

Floor of PELVIS, deeply concave, particularly in the transverse direction and inclined dorsally in the caudal part

Carnivores

Floor of PELVIS, concave, but shallower

Horse

Floor of PELVIS, flat and vertical.

Pelvic Axis, Conjugate Diameter, Diagonal Conjugate Diameter, Vertical Diameter

The following measurements of the pelvic cavity are used in obstetrics:

Pelvic axis

the imaginary line drawn in a cranial to caudal direction through the middle of all lines between the sacrum and the pelvic symphysis.

Conjugate diameter

distance from the sacral promontory to the cranial border of the pelvic symphysis. It measures the diameter of the pelvic inlet.

Diagonal conjugate diameter

distance from the sacral promontory to the caudal border of the pelvic symphysis.

Vertical diameter

diameter between the sacrum or caudal vertebra and the cranial border of the pelvic symphysis, orthogonal to the pelvic symphysis.

Ruminants, Horses, Pig

vertical diameter extends between the sacrum and the pelvic symphysis, which makes an expansion of the pelvis impossible

carnivores

sacrum is very short and the vertical diameter extends between the caudal vertebrae and the pelvic symphysis

Dogs

pelvic inlet is very oblique with the pecten of the pubis level with or behind the sacrum

pelvic cavity

whole is straight and short and causes few problems during parturition in the dog

pig

sacrum is slightly bent and the pelvic floor is flattened and has a ventral inclination caudally.

Long conjugate diameter

The pelvic inlet is very oblique and almost in the dorsal plane, resulting in a (Pigs)

Ox

pelvic roof narrows from cranial to caudal. The sacrum, which contributes most to the pelvic roof, is concave throughout its length

Ox

The lateral wall is formed by the ilial wings cranially and the pronounced ischiatic spine further caudally.

horse

Pelvic roof is formed by the sacrum and the first two caudal vertebrae and slopes slightly downward caudally.

pigs and cattle

ischiatic spine and tuber are less pronounced and therefore the sacrosciatic ligament contributes a greater part to the lateral wall of the pelvic cavity