Sacroiliac joint

Question 1

Type of Joint

Answer 1

Synovial plane joint, fibrous posteriorly

Question 2

Position

Answer 2

Posterior articulation of the pelvis. Sacrum articulates with the ilium of the pelvic girdle on each side.

Question 3

Articular Surfaces

Answer 3

Both surfaces of the ariculuar ilium and ariculuarsacrum are roughened by elevations and depressions, restricting movement and stabilising the joint.

Ilium articular surface covered in fibro cartilage.
Sacrum articular surface covered in Hyaline cartilage.

Question 4

Movements

Answer 4

Nutation- sacrum moves anterior

Counter nutation-sacrum moves backwards

Question 5

Capsule

Answer 5

fibrous cartilage surrounds the joint attached to the articular surfaces and is lined with synovial membrane

Question 6

Ligaments

Answer 6

Anterior sacroiliac ligament
Posterior sacroiliac ligament 
Interosseus sacroiliac ligament 
Accessory ligaments 
Sacrotuberous ligament 
Sacrospinous ligament 
Iliolumbar ligaments

Question 7

Anterior/Ventral sacroiliac ligament

Answer 7

lateral sacrum to medial aspect of ilium

Question 8

Interosseus sacroiliac ligament

Answer 8

Posterior aspect of the auricular surface on the ilium to the posterior aspect of the auricular surface on the sacrum

Question 9

Sacrotuberous ligament

Answer 9

PSIS, Sacral tubercles and lateral margins of Sacrum and Coccyx to Ischial tuberosity
Ischial ramus.

Question 10

Sacrospinous ligament

Answer 10

lateral margin of sacrum and coccyx to ischium spine

Question 11

ilio-lumbar ligament

Answer 11

Transverse processes of L5 to posterior aspect of the iliac crest