Sacrum Flashcards
How many vertebrae form the sacrum?
five
What portions of the sacrum develop within a cartilaginous model?
costal elements, vertebral arch, centrum; fuse between 2-5 yrs of age
When do epiphyseal plates of the sacrum fuse?
after puberty
What are the bony articulations of the sacrum>
fifth lumbar vertebra, coccyx, inominates
What is the position of the sacrum in the inominate?
superior to inferior and anterior to posterior
What are some characteristics of the sacral surface of the SI joint?
smooth, hyaline cartilage, decreases in width inferiorly and wedged between two ila
What are some characteristics of iliac surface of SI joint?
Anteriorly smooth, posteriorly fibrous, fibrocartilage
Sacrotuberous ligament
lower sacral tubercles to ischial tuberosity
Sacrospinous ligament
ischial spine to lateral margins of sacrum
What are the functions of the sacrospinous and sacrotuberous ligaments?
stabilitize to limit posterior-superior rotation of sacral apex around transverse axis
What sacral landmarks are used to identify sacral SD?
Inferior lateral angle, sacral sulci, L5
Form closure
specific properties of articular surfaces of SIJ, “how joint fits together”
Force closure
compression produced by weight, muscle action, and ligament force, “due to gravity and loading forces”
Lumbarization
transitional segment in which first sacral segment becomes like an aditional lumbar vertebra
Sacralization
Incomplete separation and differentiation of fifth lumbar
What are the tests used for sacral static testing
seated forward bending test, backward bending test, respiratory motion test, lumbosacral spring test, oblique axis passive motion
Which side will be positive in SeFBT for a unilateral SD?
positive on side of dysfunction
Which side will be positive in SeFBT for a torsion SD?
positive opposite of axis
What is a positive backward bending test and what does it indicate?
sacral sulcus appears asymmetrical throughout, sacrum is unable to flex, extended
What does a neg BBT indicate?
sacrum is flexed, unable to extend
What is the respiratory motion of the sacrum?
sacral base moves posterior during inhalation and anterior during exhalation
What is a positive lumbar spring test and what does it indicate?
lumbars do not move well into extension, sacrum is extended, unable to flex
What does a negative lumbar spring test indicate?
sacrum is flexed, unable to extend
What is the superior transverse axis?
Goes through S2 posteriorly, respiratory and craniosacral motion
What is the middle transverse axis?
Goes through S2 anteriorly, postural motion, dysfunctions along this axis will have bilateral findings
What is the inferior transverse axis?
goes through S3, innominate rotation
What does a dysfunction along an axis look like?
deep sacral sulcus opposite side of posterior ILA
What does a dysfunction along a vertical axis look like?
deep sacral sulcus same side as posterior ILA
Where is the restriction of motion in a torsion?
restriction along oblique axes
What would be the PE findings for a L/L sacral torsion?
deep sacral sulcus on R, posterior ILA on R, BBT negative, Lumbar spring negative, SeFBT on right
What would the PE findings for a R/R sacral torsion?
deep sacral sulcus on L, posterior ILA on R, BBT negative, LS negative, SeFBT on L
What would be the PE findings for a L/R sacral torsion?
deep sacral sulcus on R, posterior ILA on L, BBT positive, LS positive, SeFBT on L
What would be the PE findings for a R/L sacral torsion?
deep sacral sulcus on L, posterior ILA on R, BBT positive, LS positive, SeFBT on R
What are the PE findings for right sacrum flexed?
Deep sacral sulcus on R, posterior ILA on R, BBT neg, LS neg, SeFBT pos on R
What are the PE findings for left sacrum flexed?
deep sacral sulcus on L, posterior ILA on L, BBT neg, LS neg, SeFBT pos on R
What are the PE findings for L sacrum extended?
deep sacral sulcus on R, posterior ILA on R, BBT pos, LS pos, SeFBT pos on L
What are the PE findings for R sacrum extended?
deep sacral sulcus on L, posterior ILA on L, BBT pos, LS pos, SeFBT pos on R
What are the PE findings for bilateral sacrum flexed?
bilateral deep sacral sulcus, bilateral posterior ILA, neg SeFBT
What are the PE findings for bilateral sacrum extended?
bilateral shallow sacral sulcus, b/l posterior ILA, neg SeFBT
What does a compensated L5 look like?
Should be rotated opposite direction of sacrum, sidebends toward oblique axis of torsion
In a L/L ST or R/R sacral torsion, what does a compensated L5 look like?
neutral
In a R/L or L/R ST, what does a compensated L5 look like?
extended/flexed
What is the setup for bilateral sacral flexion ME?
ABduct leg and internally rotate LE, use heel of hand to apply superior/anterior force to engage RB, resist motion with exhalation
What is the setup for bilateral sacral extension ME?
ABduct leg and externally rotate legs, pt in “TV watching position” apply an anterior/inferior force at sacral base, resisting during inhalation
What is the setup for unilateral sacral flexion ME?
ABduct and internally rotate leg. apply anterior superior force, resist exhalation motion
What is the setup for unilateral sacral extension ME?
ABduct and externally rotate leg, have pt in “TV watching” position, apply anterior inferior force at sacral base, resist inhalation motion
What is the setup for forward torsion tx?
pt is lateral recumbent, hugging table, axis side down, hips and knees flexed to 90 degrees, physician monitoring L5/S1, flex hips until L5 is neutral relative to S1, push pts feet off table and have them resist motion
What is the setup for a backward torsion?
Pt lateral recumbent, axis side down, top hip and knee flexed to 90 degrees, induce posterior rotation (pts back on table), drop top leg off table and have pt resist motion
What is the setup for sacral BLT - b/l sacral extension?
Pt supine, caudal palm lifts ILAs anterior to pt of ligamentous balance
What is the setup for sacral BLT - b/l sacral flexion?
pt supine, caudal hand lift sacral base anterior to point of ligamentous balance, use cephalad hand to extend L5, encourage sacral flexion
What is the setup for sacral BLT - forward torsion?
pt supine, caudal hand apply anterior pressure to sacral base to point of ligamentous balance, push sacral base to flexion or L5 to ext
What is the setup for sacral BLT - backward torsion?
pt supine, caudal hand apply anterior pressure to ILA to point of ligamentous balance, flex L5
