ischium


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ischium

 [is´ke-um]
the inferior, dorsal portion of the hip bone. See anatomic Table of Bones in the Appendices.

is·chi·um

, gen.

is·chi·i

, pl.

is·chi·a

(is'kē-ŭm, is'kē-ī, is'kē-ă), [TA] Avoid the mispronunciation ish'ē-ŭm.
The lower and posterior part of the hip bone, distinct at birth but later becoming fused with the ilium and pubis; it consists of a body, where it joins the ilium and superior ramus of the pubis to form the acetabulum, and a ramus joining the inferior ramus of the pubis.
Synonym(s): os ischii [TA], ischial bone
[Mod. L. fr. G. ischion, hip]

ischium

/is·chi·um/ (is´ke-um) pl. is´chia   [L.] the inferior dorsal portion of the hip bone (os coxae); it is a separate bone in early life.

ischium

(ĭs′kē-əm)
n. pl. is·chia (-kē-ə)
The lowest of the three major bones that constitute each half of the pelvis.

is′chi·al (-əl) adj.

ischium

[is′kē·əm] pl. ischia
Etymology: L; Gk, ischion, hip joint
one of the three parts of the hip bone, which joins the ilium and the pubis to form the acetabulum. The ischium comprises the dorsal part of the hip bone and is divided into the body of the ischium, which forms the posteroinferior two fifths of the acetabulum, and the ramus, which joins the inferior ramus of the pubis. The spine of the ischium provides attachment for various muscles, such as the gemellus superior, the coccygeus, and the levator ani. The greater sciatic notch above the spine transmits the superior and inferior gluteal vessels and various nerves, such as gluteal nerves and the sciatic nerve. A notch below the spine of the ischium transmits various ligaments, vessels, and nerves for other parts. The large dorsal tuberosity of the ischium provides attachment for various muscles, such as the adductor longus, the semimembranosus, the biceps femoris, and the semitendinosus. Compare ilium, pubis.

is·chi·um

, pl. ischia (is'kē-ŭm, -ă) [TA]
The lower and posterior part of the hip bone, distinct at birth but later becoming fused with the ilium and pubis; it consists of a body, where it joins the ilium and superior ramus of the pubis to form the acetabulum, and a ramus joining the inferior ramus of the pubis.
Synonym(s): ischial bone.
[Mod. L. fr. G. ischion, hip]

ischium

The lowest of three bones into which the innominate bone, comprising one side of the pelvis, is divided. The ischial tuberosities are the bony prominences on which we normally sit.

ischium

the ventral bone of the PELVIC GIRDLE in vertebrates, bearing the weight of a sitting human.

os ischii

; ischium lower posterior part of hip bone

ischium

the caudal, dorsal portion of the hip bone. See Table 10. See also os coxae.
References in periodicals archive ?
Representative images, including: a plain radiograph (Figure 1), 3D reconstructed computed tomography (Figue 2) and T1 coronal magnetic resonance imaging (Figure 3) indicated a bony excrescence from the inferior aspect of the left ischium measuring 1.
Plain radiography of the pelvis showed complete bilateral absence of the ilium, with normal well-formed ischium, the superior and inferior pubic rami, as well as the femoral heads bilaterally.
A limitation of our method is that the ischium must be visible on the lateral radiograph.