Pelvic Girdle Flashcards
Anatomy
Bones
Arthrology
Bones of the pelvic girdle
2 innominates Ilium Ischium Pubis Sacrum
Athrology of the pelvic girdle
2 SI joints and pubic symphysis
functionally, include 2 hip joints and L4-L5 and L5-S1 articulation
Primary function of SI joints and pubic symphysis
Load transmission
Form closure
Relies on the shape of a joint for stabilization
Ex: hip is stable because of its shape but form closure is not very effective at the SI joint
Force closure
Accomplished through supportive structures (ligaments) and through compressive forces applied by muscles
Primary means of stabilization at the SI joint
The ligaments of the pelvic girdle joints are important for 2 reasons
Critical joint stability
Help with diagnosis of joint dysfunction
Palpable ligaments
Long posterior SI Short posterior SI Sacrotuberous Iliolumbar Pubic ligaments
Long posterior SI
Intrinsic
PSIS to sacral border
Checks anterior ilial rotation
Short posterior SI ligament
Intrinsic
Extensive sacral and ilial attachment
Checks all ilial and sacral motion
TTP with all SI injuries
Sacrotuberous ligament
Extrinsic
Lower sacrum to ischial tuberosity
Checks posterior rotation of ilium, sacral flexion, and sacral rotation to same side
Iliolumbar ligament
Extrinsic
Ilial crest to L5
Stabilizes L-S junction
Pubic ligaments
Intrinsic
Stabilizes pubic symphysis in all directions
Anterior rotation
ASIS moves down, PSIS moves up
Occurs with hip degrees extension
Important in terminal stance phase of gait
Checked by long posterior SI ligament
Posterior rotation
ASIS moves up, PSIS moves down, coupled with hip flexion, checked by sacrotuberous ligament
Inflare
ASIS moves medial, PSIS moves lateral, occurs with hip IR, observed during heel strike through losing response
Outflare
ASIS moves lateral, PSIS moves medial, coupled with hip ER, occurs from midstance through preswing
Upslip
Superior shear motion
Typically a dysfunction
Sacral flexion
Sacral base moves anterior, apex moves posterior, occurs with initial trunk backward bending, occurs during exhalation
Sacral extension
base moves posterior
apex moves anterior
Occurs with initial trunk flexion and with inhalation
Sacral rotation
Side bend to R=rotation of L, R comes forward, L moves back
Pubic motion
Superior and inferior glide
Anterior and posterior glide
Separation
Rotation
