Sacrum & Coccyx

Although the size and degree of curvature of the sacrum vary considerably in different patients, the bone is normally _____

longer, narrower, more evenly curved, and more vertical in position in males than in females

The coccyx is composed of ___-____ rudimentary vertebrae that have a tendency to fuse into one bone in the adult

3-5 (usually four)

The female sacrum is more ____ curved, with its greatest curvature in the ___ half of the bone, ,which results in ___

acutely lower a sharper angle at the junction of the lumbar and pelvic curves

On each side of the sacral base is a large, winglike lateral mass called the ___

ala

At the superoanterior part of the lateral surface of each ala is the ____ ( a large articular process for articulation with similarly shaped processes on the iliac bones of the pelvis )

articular surface

The ____ projects superiorly from the posterolateral aspect of the first coccygeal segment to join the sacral cornua

coccygeal cornua

The inferior surfaces of the apex of the sacrum has an oval facet for articulation with the ___ &____ (two processes that project inferiorly from the posterolateral aspect of the last sacrl segment to join the coocygeal cornua)

coccyx and the sacral cornua

what is the sacral canal?

continuation of the vertebral canal -contained within the bone and transmits the sacral nerves

The coccyx ____ in size from its base inferiorly to its apex

diminishes

The sacrum is wedged between___, with its broad base directed ___, __, and __ and its apex directed __ and __.

iliac bones of the pelvis obliquely, superiorly, and anteriorly posteriorly, and inferiorly

The superior surface of the base of the sacrum corresponds in size and shape to the _____

inferior surface of the last lumbar segment, with which it articulates to form the lumbosacral junction

Form the coccyx's articulation with the sacrum, it curves ___ &___, often deviating from the midline of the body

inferiorly and anteriorly

The superior portion of the first sacral segment remains distinct and resembles the vertebrae of the _____ region

lumbar

Each of the anterior an posterior walls of the sacral canal is perforated by four pairs of ____ for passage of the sacral nerves and blood vessels

pelvic sacral formaina

Directly behind the bodies of the sacral segments is the ____

sacral canal

At its superior anterior margin, the base of the sacrum has a prominent ridge termed the __ __

sacral promontory

The _____ of the first sacral segment articulate with the inferior articular processes of the last lumbar vertebrae to form the last pair of zyagpophyseal joints

superior articular processes

sacrum What forms the last pair of intervertebral foramina?

the concavities on the upper surface of the pedicles of the first sacral segment and the corresponding concavities on the lower surface of the pedicles of the last lumbar segment

The sacrum is formed by ______

the fusion of the five sacral vertebral segment into a curved, triangular bone