Regions of the Vertebral Column: Sacrum and Coccyx

Question 1

What is the position of the sacral zygapophysis in adults?

Answer 1

The zygapophysis lies in the coronal plane for L5/S1

Question 2

What is the orientation of the first sacral superior articular facet?

Answer 2

Backward, upward, medial (BUM); typically concave

Question 3

From the anterior view, the intervetebral discs of sacrum will be replaced by what feature?

Answer 3

Transverse ridges

Question 4

What forms the median sacral crest?

Answer 4

Fused spinous processes and their spinous tubercles

Question 5

What forms the intermediate sacral crest?

Answer 5

Fused articular processes and their facets

Question 6

What features may be identified along the intermediate sacral crest?

Answer 6

The mammillary process of S1 and the sacral cornu of S5

Question 7

What is the sacral hiatus?

Answer 7

The inferior opening of the sacral spinal canal

Question 8

An imaginary line drawn from the transverse process of S1 to the inferior lateral sacral angle will form what feature?

Answer 8

The lateral sacral crest

Question 9

What is the sacral tubersoity?

Answer 9

The enlarges transverse tubercle of S2

Question 10

What is the name of the joint formed by the sacral tuberosity?

Answer 10

the accessory sacro-iliac joint

Question 11

What feature is associated with the transverse tubercle of S5?

Answer 11

The inferior and lateral (inferolateral) sacral angle

Question 12

What feature is identified on the lateral surface of S1-S3?

Answer 12

Auricular surface

Question 13

What is the sacral promontory?

Answer 13

The bulging anterior surface of the superior epiphyseal rim of S1

Question 14

How many synovial joints are typically present at sacrum?

Answer 14

Four

Question 15

What joint classifications are typically present at sacrum?

Answer 15

Fibrous (amphiarthrosis) syndesmosis, cartilaginous (amphiarthrosis) symphysis, and synovial plane (diarthrosis arthrodia)

Question 16

What forms the posterior boundary for the fifth sacral spinal nerve intervertebral foramen?

Answer 16

Sacral cocrnu, coccygeal cornu, superficial posterior sacrococcygeal ligament and intercornual ligament

Question 17

What forms the anterior boundary for the fifth sacral spinal nerve intervertebral foramen?

Answer 17

Vertebral body S5, vertebral body Co1, deep posterior sacrococcygeal ligament and intervertebral disc

Question 18

What is the homolog for the posterior longitudinal ligament at S5?

Answer 18

Deep posterior sacrococcygeal ligament

Question 19

What is the homolog for the anterior longitudinal ligament at S5?

Answer 19

Anterior sacrococcygeal ligament

Question 20

What is the homolog for the ligamentum flavum at S5?

Answer 20

Superficial posterior sacrococcygeal ligament

Question 21

What forms the inferior boundary for the spinal canal?

Answer 21

The union of the superficial posterior and deep posterior sacrococcygeal ligaments

Question 22

What ligament is formed by the union of ht esuperficial posterior sacrococcygeal and the deep poseterior sacrococcygeal ligaments at Co1?

Answer 22

The posterior sacrococcygeal ligament

Question 23

What ligament divides the sciatic foramen into the greater and lesser sciatic foramina?

Answer 23

Sacrospinous ligament

Question 24

Which ligament represents a thickening of the fibrous capsule of the sacro-iliac joint?

Answer 24

Anterior sacro-iliac ligament

Question 25

Which ligament is the strongest of the sacro-iliac ligaments and is penetrated by dorsal rami of the sacral spinal nerves?

Answer 25

Interosseous sacro-iliac ligament

Question 26

Which ligament will attach the intermediate sacral crest of S1, lateral sacral crest of S2 to the posterior superior iliac spine?

Answer 26

Short posterior sacro-iliac ligament

Question 27

Which ligament attaches the lateral sacral crest of S3 and S4 to the posterior superior iliac spine?

Answer 27

Long posterior sacro-iliac ligament

Question 28

What is the homolog for the inferior articular process and facet at S5?

Answer 28

Sacral cornu

Question 29

What is the homolog for the superior articular process and facet at Co1?

Answer 29

Coccygeal cornu

Question 30

What is the homolog for the capsular ligament at S5?

Answer 30

Intercornual ligament

Question 31

What is the number of coccygeal somites?

Answer 31

Ten

Question 32

What is the typical number of segments which unite to form the adult coccyx?

Answer 32

4 segments

Question 33

When is ossification of coccyx completed?

Answer 33

About age 30

Question 34

What is the direction of fusion of coccygeal segments?

Answer 34

From caudal to cranial, the last segments to fuse together are Co1 and Co2

Question 35

What is the direction of the coccygeal curve?

Answer 35

Posterior (kyphotic)

Question 36

What is the major motion and range of motion for coccyx?

Answer 36

Flexion-extensionn, 5-20 degrees

Question 37

How many coccygeal nerves are present in the fetus?

Answer 37

Typically 5 pairs of coccygeal nerves are present

Question 38

How many coccygeal nerves are present in the adult?

Answer 38

Typically only one pair of coccygeal nerves remain in the adult

Question 39

What forms the coccygeal nerve plexus?

Answer 39

S4, S5, and Co1 nerves

Question 40

What is the ganglion impar?

Answer 40

A midline sympathetic ganglion

Question 41

What is the coccygeal glomus or coccygeal body?

Answer 41

An enlarged encapsulated arteriovenous anastomosis located near the last segment of coccyx