Exam 2: Sacrum And Coccyx Flashcards
Generic shape of 1st sacral vertebral body
Reniform
What muscle may attach to 1st sacral body
Psoas major
How many joint surfaces present on vertebral body of S1
5
Origin of sacral ala
S1 transverse process and costal element originate from vertebral body and possibly pedicle
Part of sacral ala derived from costal element
Anterior 2/3
Position of sacral zygapophysis in adults
Coronal plane for L5/S1
Orientation of S1 superior articular facet
BUM
Concave
Muscles attach to sacral mammillary processes
Multifidis
Fusion of vertebral bodies of sacrum across intervertebral disc is called _____
Synostosis
Anterior view, IVD of sacrum are replaced by
Transverse ridges
What forms median sacral crest
Fused spinous processes and their spinous tubercles
Muscles that may attach to median sacral crest
Latissimus dorsi
iliocostalis lumborum
longissimus thoracic
What forms intermediate sacral crest
Fused articular processes and their facets
What features may be identified along intermediate sacral crest
Mammillary process of S1
Sacral cornu of S5
What does sacral cornu represent
Inferior articular process and facet of S5
Name of inferior opening of sacral spinal canal
Sacral hiatus
What forms lateral sacral crest
Fused transverse processes and transverse tubercles
Features that may be identified along lateral sacral crest
S1 transverse tubercle
Sacral tuberosity of S2
Transverse tubercles of S3-5
Name of joint formed by sacral tuberosity
Accessory sacro-iliac joint
Feature associated with transverse tubercle of S5
Inferior and lateral sacral angle
Muscles may attach to lateral sacral crest
Multifidis
Iliocostalis lumborum
Muscle said to attach to dorsal surface of sacrum
Iliacus
Feature identified on lateral surface of S1-S3
Auricular surface
What is sacral promontory
Bulging anterior surface of superior epiphyseal rim of S1
Continuation of anterior longitudinal ligament below S3 forms what lig
Anterior sacrococcygeal ligament
Continuation of posterior longitudinal ligament below S3 forms what lig
Deep posterior sacrococcygeal ligament
What form posterior boundary for 5th sacral spinal nerve IVF
Sacral cornu, coccygeal cornu, superficial posterior sacrococcygeal lig and intercornual lig
What forms anterior boundary for 5th sacral spinal nerve IVF
S5 and Co1 bodies, deep posterior sacrococcygeal lig and IVD
What ligament is attached to sacral hiatus
Superficial posterior sacrococcygeal lig
Synovial joint surfaces present at sacrum
2 superior articular facets
2 auricular facets
How many synovial joints present at sacrum
4
Joint classifications present at sacrum
Fibrous syndesmosis
Cartilaginous symphysis
Synovial plane
Homolog for posterior longitudinal ligament at S5
Deep posterior soacoroccygeal ligament
Homolog for ligamentum flavum at S5
Superficial posterior sacrococcygeal ligament
What forms inferior boundary for spinal canal
Union of superficial posterior and deep posterior sacrococcygeal ligaments
Ligament formed by union of superficial and deep sacrococcygeal ligs at Co1
Posterior sacrococcygeal ligament
Ligament divides sciatic foramen into greater and lesser sciatic foramina
Sacrospinous ligament
Ligament has broad attachment along lateral margin of sacrum and coccyx and then attached to ischial tuberosity
Sacrotuberous lig
Ligament represents thickening of fibrous capsule of sacro-iliac joint
Anterior sacro-iliac ligament
Ligament is strongest of sacro-iliac ligs and is penetrated by dorsal rami of sacral nerves
Interosseous sacro-iliac lig
What ligament will attach intermediate sacral crest of S1, lateral sacral crest of S2 to posterior superior iliac spine
Short posterior sacro-iliac lig
Ligament attaches lateral sacral crest of S3 and S4 to posterior superior iliac spine
Long posterior sacro-iliac ligament
Homolog for interior articular process and facet at S5
Sacral cornu
Homolog for superior articular process and facet at Co1
Coccygeal cornu
Homolog for capsular ligament at S5
Intercornual ligament
When is ossification of coccyx completed
30
Direction of fusion of coccygeal segments
Caudal to cranial
Co1 and Co2 are last to fuse
Direction of coccygeal curve
Posterior (kyphotic)
Major motion and range of motion for coccyx
Flexion — extension
5-20 degrees
How many coccygeal nerve present in fetus
Typically 5 pairs
How many coccygeal nerve present in the adult
Typically only 1