Sacrum Flashcards
Which sacral segment is described as wedge-shaped from a lateral view?
the first sacral segment
What muscle(s) may attach to the first sacral vertebral body?
psoas major
What is the position of the sacral zygapophysis in children?
the zygapophysis lies in the coronal plane
What is the position of the sacral zygapophysis in adults?
the zygapophysis lies in the coronal plane for L5/S1
What is the orientation of the first sacral superior articular facet?
backward, upward, medial (BUM); typically concave
What muscles will attach to the sacral mammillary processes?
multifidis
From the anterior view, the intervertebral discs of sacrum will be replaced by what feature?
transverse ridges
What part of the sacral ala continues along the ventral surface of sacrum to about S4?
the costal element
What forms the medial sacral crest?
fused spinous processes and their spinous tubercles
An imaginary line drawn from the superior articular process of S1 to the sacral cornu will form what feature?
intermediate sacral crest
What muscles may attach to the median sacral crest?
latissimus dorsi, iliocostalis lumborum, longissimus thoracis
What features may be identified along the intermediate sacral crest?
the mammillary process of S1 and the sacral cornu of S5
What is the remnant of the inferior articular process and facet of S5?
the sacral cornu
What is the name of the inferior opening of the sacral spinal canal?
sacral hiatus
An imaginary line drawn from the transverse process of S1 to the inferior lateral sacral angle will form what feature?
the lateral sacral crest
What features may be identified along the lateral sacral crest:
S1 transverse tubercle, sacral tuberosity of S2, transverse tubercles of S3-S5
What is the sacral tuberosity?
the enlarged transverse tubercle of S2
What is the name of the joint formed by the sacral tuberosity?
the accessory sacro-iliac joint
What muscle is said to attach to the dorsal surface of sacrum?
iliacus
What feature is identified on the lateral surface of S1-S3?
auricular surface
What classification of joint is formed by the auricular surface of sacrum?
synovial plane (diarthrosis arthrodia)
What feature does the anterior surface of the superior epiphyseal rim of S1 form?
the sacral promontory
What forms the posterior boundary for the fifth sacral spinal nerve intervertebral foramen?
sacral cornu, coccygeal cornu, superficial posterior sacrococcygeal ligament and intercornual ligament
What forms the anterior boundary for the fifth sacral spinal nerve intervertebral foramen?
vertebral body S5, vertebral body Co1, deep posterior sacrococcygeal ligament and intervertebral disc
What is the homolog for that posterior longitudinal ligament at S5?
deep posterior sacrococcygeal ligament
What is the homolog for the anterior longitudinal ligament at S5?
anterior sacrococcygeal ligament
What is the homolog for the ligamentum flavum at S5?
superficial posterior sacrococcygeal ligament
What forms the inferior boundary for the spinal canal?
the union of the superficial posterior and deep posterior sacrococcygeal ligaments
What ligament is formed by the union of the superficial posterior sacrococcygeal and the deep posterior sacrococcygeal ligaments at Co1?
the posterior sacrococcygeal ligament
What ligament is a honolog of the intertransverse ligement at S5?
lateral sacrococcygeal ligament
What ligament divides the sciatic foramen into the greater and lesser sciatic foramina?
sacrospinous ligament
Which ligament has abroad attachment along the lateral margin of sacrum and coccyx and then attaches to the ischial tuberostiy?
sacrotuberous ligament
Which ligament represents a thickening of the fibrous capsule of the sacro-iliac joint?
anterior sacro-iliac ligament
Which ligament is the strongest of the sacro-iliac ligaments and is penetrated by dorsal rami of the sacral spinal nerves?
interosseous sacro-iliac ligament
Which ligament will attach the intermediate sacral crest of S1, lateral sacral crest of S2 to the posterior superior iliac spine?
short posterior sacro-iliac ligament
Which ligament attaches the lateral sacral crest of S3 and S4 to the posterior superior iliac spine?
long posterior sacro-iliac ligament
What is the homolog for the inferior articular process and facet at S5?
sacral cornu
What is the homolog for the superior articular process and facet at Co1?
coccygeal cornu
What is the homolog for the capsular ligament at S5?
intercornual ligament
