Pelvic Girdle pt. 1 (Sacrum & Coccyx)

Name the following:

• Bone?

• Side?

• View?

• Specific Surface? (if applicable)

• A?

sacrum, unsided, superior, sacral canal

Name the following:

• Bone?

• Side?

• View?

• Specific Surface? (if applicable)

• B?

sacrum, unsided, superior, ala

Name the following:

• Bone?

• Side?

• View?

• Specific Surface? (if applicable)

• A?

sacrum, unsided, superior, base

Name the following:

• Bone?

• Side?

• View?

• Specific Surface? (if applicable)

• A?

sacrum, unsided, anterior, pelvic, ala

Name the following:

• Bone?

• Side?

• View?

• Specific Surface? (if applicable)

• B?

sacrum, unsided, anterior, pelvic, transverse ridge/line

Name the following:

• Bone?

• Side?

• View?

• Specific Surface? (if applicable)

• C?

sacrum, unsided, anterior, pelvic, anterior sacral foramen

Name the following:

• Bone?

• Side?

• View?

• Specific Surface? (if applicable)

• D?

sacrum, unsided, anterior, pelvic, apex

Name the following:

• Bone?

• Side?

• View?

• Specific Surface? (if applicable)

• A?

sacrum, unsided, posterior, dorsal, superior articular facet

Name the following:

• Bone?

• Side?

• View?

• Specific Surface? (if applicable)

• B?

sacrum, unsided, posterior, dorsal, median sacral crest

Name the following:

• Bone?

• Side?

• View?

• Specific Surface? (if applicable)

• C?

sacrum, unsided, posterior, dorsal, posterior sacral foramen

Name the following:

• Bone?

• Side?

• View?

• Specific Surface? (if applicable)

• D?

sacrum, unsided, posterior, dorsal, lateral sacral crest

Name the following:

• Bone?

• Side?

• View?

• Specific Surface? (if applicable)

• A?

sacrum, unsided, lateral, promontory

Name the following:

• Bone?

• Side?

• View?

• Specific Surface? (if applicable)

• B?

sacrum, unsided, lateral, auricular surface

Name the following:

• Bone?

• Side?

• View?

• Specific Surface? (if applicable)

• A?

coccyx, unsided, anterior, coccygeal cornua

Name the following:

• Bone?

• Side?

• View?

• Specific Surface? (if applicable)

• B?

coccyx, unsided, anterior, rudimentary transverse process

Which bone is the most inferior/last portion of our spine & axial skeleton?

sacrum

The sacrum is still apart of the ______ even though it is technically in the pelvic girdle grouping of bones

spine

Sacrum Articulation

• Bilaterally with the ______

• Inferiorly with the _______

ilium, coccyx

The sacrum consists of ___ sacral vertebrae that _____ together during _______________ to create the wedge-shaped bone. Due to human variation it can have ___ or ___ vertebrae but ___ is the “normal” amount. Sometimes you will see ____ fused with the ____.

5, fuse, adolescence, 4, 6, 5, S1, L5

What type of curvature does the sacrum have?

Which other vertebrae type has this same curvature?

kyphotic, thoracic

the entire superior portion of the sacrum; includes the body/centrum of S1; includes the top portion of the Ala

base

the anterior facing horizontal lip spanning the top edge of the centrum of S1

promontory

What is technically the most anterior and superior portion of the sacrum?

promontory

the promontory on the sacrum sticks into the _______ _______

pelvic cavity

hole that runs through the sacrum superior to inferior

sacral canal

the sacral canal is the continuation of the ____________ ________

vertebral canal

The superior articular facets of the sacrum are the 2 flared _________-facing articulations on ___ that articulate with the ________ Articular Facets of ___.

posterior, S1, inferior, L5

The shape of the sacral superior articular facets matches the positioning of the superiors articular facets of WHICH type of vertebrae?

lumbar (cupped, turned inwards)

When looking at the sacrum at either the front or back face and dividing the sacrum into 3 vertical columns, what are the 2 lateral winged columns on either side? What makes up the 3rd central column?

Ala, sacral vertebrae

The Ala are formed from the _____________ ___________ of all the sacral vertebrae fused together

transverse processes

if you held the sacrum like you would hold an Xbox controller the _____ make up the handles

Ala

large smooth surfaces on the top half of the lateral edge of each Ala

auricular surfaces

What do the auricular surfaces of the sacrum articulate with?

ilium (bone of the pelvis)

Which feature on the sacrum is part of the Sacroiliac Joint?

auricular surfaces

What are the auricular surfaces on the sacrum shaped like? (2)

ears, kidney beans

What are the 4 main superior features that are apart of the base of the sacrum?

centrum of S1, promontory, top part of the Ala, superior articular facets

the entire smooth and concave anterior side of the sacrum; faces forward into the pelvic cavity

pelvic surface

the entire rough convex surface on the posterior side of the sacrum

dorsal surface

Which surface of the sacrum faces ANTERIORLY: pelvic or dorsal?

pelvic

Which surface of the sacrum faces POSTERIORLY: pelvic or dorsal?

dorsal

Which surface of the sacrum is more CONCAVE: pelvic or dorsal?

pelvic

Which surface of the sacrum is more CONVEX: pelvic or dorsal?

dorsal

Which surface of the sacrum is more SMOOTH: pelvic or dorsal?

pelvic

Which surface of the sacrum is more ROUGH: pelvic or dorsal?

dorsal

the anterior holes on either side of each sacral vertebra (4 on each side)

anterior sacral foramen

the posterior holes on either side of each sacral vertebra (4 on each side)

posterior sacral foramen

The anterior and posterior sacral foramina allows for passage of the ________ ________

ventral nerves

horizontal ridges/lines stretching across from each Anterior Sacral Foramen to its matching pair

transverse line/ridge

scars marking where the sacral vertebrae have fused together vertically

transverse line/ridge

How many TOTAL anterior sacral foramina does a sacrum have if it has the normal 5 sacral vertebrae?

8

How many TOTAL posterior sacral foramina does a sacrum have if it has the normal 5 sacral vertebrae?

8

How many TOTAL transverse lines/ridges does a sacrum have if it has the normal 5 sacral vertebrae?

4

the pointed & most inferior end of the sacrum

apex

the part of the sacrum where the coccyx articulates

apex

Does the apex of the sacrum point ANTERIORLY or POSTERIORLY?

anteriorly

ridge that runs down the middle of the dorsal surface of the sacrum superior to inferior

median sacral crest

The median sacral crest if formed from the fused ________ ____________ of the sacral vertebrae

spinous processes

part of the sacrum that looks like the spine of a Stegosaurus

median sacral crest

bumpy ridges of bone on the lateral sides of the dorsal surface of the sacrum

lateral sacral crests

Which sacral feature do the lateral sacral crests specifically NOT include?

edge of the auricular surfaces

Are the lateral sacral crests MORE or LESS lateral than the posterior sacral foramina?

more

The lateral sacral crests form from part of the fusion of the _____________ ____________ of the sacral vertebrae

transverse processes

The sacrum feature that looks more like a collection of bumps than an actual line

lateral sacral crest

Which bone is our tailbone?

coccyx

the small triangular bone at the very bottom of the vertebral column

coccyx

the coccyx consists of __-__ very tiny vertebrae (Cx2-5) usually ______ together

4-5, fused

Coccyx Articulation

• Superiorly with the _____ of the ________

apex, sacrum

The coccyx is considered a ________ structure aka it is left over from our _____________ history back when we had ____. Some muscles and ligaments attach to it and anchor our _______ ______, so it is still used just not for a ____.

vestigial, evolutionary, tails, pelvic floor, tail

Which bone is very small, fragile, and painful if injured?

coccyx

Which bone can you break or dislocate during childbirth?

coccyx

How many distinct structures does the coccyx have?

2

the 2 more medial little horns on the top of the Cx1 coccyx vertebra

Coccygeal Cornua

Which feature of the coccyx is what actually articulates with the Apex of the sacrum?

Coccygeal Cornua

the 2 small lateral projections on the Cx1 coccyx vertebra inferior to the Coccygeal Cornua

Rudimentary Transverse Processes