sacroiliac joint -pelvis Flashcards
the pelvis is a bowl shape - the force transfers through which structure?
pubic symphysis
- distribute forces around the circle –> keeps going
bone - pelvis
in standing where is the ASIS in relation to the ipsilateral PSIS?
should be lower
what is a hip hike?
a movement that involves raising the hip on the non-stance (contralateral) leg while keeping the hips pointed forward and the core stable
what is a hip drop?
non stance leg (contralateral) is dropping below pelvis
what is the force distribution of the pelvis?
forces from gravity coming down into SIJ, forces coming up through femur –> distrubtes forces around the circle and keeps going.
* the SIJ and pubic symphysis will disipate and redistribute forces
What are the ligaments of the sacrum and pelvis?
- ilioilumbar ligament
- anterior sacroiliac ligament
- posterior (dorsal) sacroiliac ligament
- sacrotuberous ligament
- sacrospinous ligament
what happens if there is ossification of ligaments in sarcum and pelvis? (ligametns in general too)
repeated pressure can cause this and it can then compress nerves, and limit mobility beyond normal limited range
what is the significane of the interosseous SI ligament?
fills space between sacrum and ilium. it is the **most important stabilizer **
arthrokinematics
during functional tasks what is the rotatory degree of SIJ? what is translation of SIJ?
rotatory: 1-3° (around any axis
translation: 1 mm
osteokinematics
what is the closed packed position of SIJ?
nutation
* partially due to strength of ligaments (becoming taut) and joint surfaces
osteokinematics
what ligaments become taut in nutation of sacrum?
- sacroiliac interosseous ligament
- sacrotuberous ligament
- sacrospinous ligament
osteokinematics
anterior movement of sacrum in relation to ilium
and/or
ilium rotates posterior on sacrum
what motion is occuring?
nutation
osteokinematics - sacrum
what ligaments become taut with counter nutation
interosseous ligament
long posterior sacroiliac ligament
which ligament is the most important stabilizer for the SIJ?
interosseous sacroiliac ligament
what is movement and rotation for pelvic torsion?
2 mm of movement
1° of rotation