Chapter 2 Flashcards
Are the biomechanics of the pelvis a confirmed and highly agreed upon?
no, it is a controversial area
Debate on amount of SI motion
For years it was thought that there was no motion.
What is the motion classification of the SI joint?
Diarthrodial
Upper 1/3 is an amphiarthrosis
What is the Importance in SI joint in relation to low back pain
Much so-called “low back pain” is caused by sacroiliac problems.
b) Often undiagnosed or incorrectly diagnosed.
Major mechanical functions of pelvis
a) Attaches the spine to the lower extremities and transfers weight to them
b) Shock absorption
c) Gyroscopic action during gait
d) In females, important in the birth process
what makes up the pelvis joints?
Pelvis consists of a three joint complex
a) 2 SI joints
b) Pubic symphysis
What kind of joint is the SI joint and what kind of surfaces does it have?
Synovial joint with atypical surfaces
What kind of joint is the pubic symphysis?
Pubic symphysis classified as a fibrocartilaginous joint
a) Amphiarthrosis
What 3 surfaces make up the SI joint?
Auricular surface
Iliac surface
Sacral surface
What is the appearance of the auricular surface?
(1) Ear (auricular) shaped or boot shaped
(2) Cephalad portion
(a) Referred to as the “upper joint”
(3) Caudad portion
(a) Referred to as the “lower joint”
What plane is the auricular surface in?
Predominantly in the sagittal plane (10° to sagittal plane)
What are the characteristics of the iliac surface?
(1) Fibrocartilage
(2) Central convex ridge
(3) Large rough bony surface posterior and superior to joint for ligamentous attachment
(4) Iliac tuberosity behind the joint
(a) Roughened area behind jt.
What are the characterics of the sacral surface?
(1) Hyaline cartilage
(2) Three times thicker than iliac surface
(3) Central groove (concavity)
(4) Wedge shaped superior to inferior (viewed P-A, A-P)
(5) S-shape anterior to posterior (viewed from side)
What is the pubic joint characteristic?
a) Articulation in median plane
b) Amphiarthrosis
c) Contains interpubic fibrocartilaginous disc
What are the intrinsic ligaments of the pelvis?
- bind sacrum to the ilium
Anterior ligament
(a) Anterior superior
(b) Anterior inferior
Posterior SI ligament
(a) Dorsal ligaments
(b) Interosseous SI ligament
What are the extrinsic ligaments of the pelvis?
(1) Sacrotuberous ligament
(2) Sacrospinous ligament
(3) Iliolumbar ligaments
What muscle crosses the SI joint?
None, no muscle crosses the SI joint
What muscles influence SI motion?
(1) Multifidus, erector spinae (SI ligament)
(2) Hamstrings, gluteus max., and piriformis have fibrous attachment to sacrotuberous ligament
(3) Psoas (anterior joint capsule)
(4) Quadratus lumborum (iliolumbar ligaments)
What is the innervation of the pelvis?
Exact innervation is debated1, but neural elements have been identified in the joint capsule and adjoining ligaments suggesting innervation for both pain and proprioception
What is the joint architecture of the SI joint?
(1) Synovial diarthrodial joint
(2) Auricular (ear) shape
(3) Corresponding groove/ridge
(4) Locking sacral wedge shape, plus interlocking sacral S configuration
Which gender has a greater “S” shape in their SI joint and what does this lead to?
Males have an increased “S” and it associates with decreased mobility
How does the SI joint appear at birth?
a) Joints undeveloped, smooth and flat, glide in any direction; stability provided by ligaments
b) Begin to develop during walking
How does the SI joint appear in the teens?
a) Roughening of surfaces, development of grooves and ridges
(1) Male more pronounced than female
b) Track bound movement develops
What occurs in the SI joint in the 3rd to 4th decade?
a) Articular changes in surface anatomy are well established.
b) Joint surfaces become more irregular.
c) enlargement of iliac tuberosity
d) beginning of joint surface erosions
e) possible osteoarthrosis (DJD) on iliac surface (more in males)
What occurs in the SI joint in the 5th and 6th decade?
a) Joint surfaces become more irregular.
b) Each individual joint is unique in its topography to varying degrees (more pronounced in males).
c) possible osteoarthrosis (DJD) developing on sacral surface and continuing on iliac surface (more in males)
d) possible development of joint adhesions, osteophytes, and fusion
What occurs in the SI joint in the 7th decade and beyond?
a) interarticular adhesions
b) high prevalence of bony ankylosis (fusion)
(c) Fusion occurs mainly in the superior part of the joint.
What are the two weight bearing arches of the pelvis?
Anterior and posterior arch
What is the function of the posterior arch?
Posterior arch
(a) Major weight bearer
(b) First three sacral segments
(c) Two pillars of bone running through
the SI and acetabular fossa
What resists the gravitational forces acting on the posterior arch in terms of weight bearing in the pelvis?
It is a down and posterior force which is resisted by:
(a) wedge shaped sacrum
(ii) Down and anterior; resisted by: (a) “S” shaped joint (b) posterior ligaments (c) interosseous ligaments (d) sacrotuberous ligaments
What is the anterior arch of the pelvis?
(a) Pubic rami
(b) Connects posterior arches and acts as a compression strut
What part of the SI joint promotes stability through form closure?
(1) Wedge shape of the sacrum
(2) Interlocking groove (sacrum) and ridge (ilium)
(3) S-shaped joint surfaces
What part of the SI joint stabilizes the joint through force closure?
Tension in muscles, ligaments and thoracolumbar fascia aids in stabilizing the SI joints (force closure).
(1) Creates lateral to medial pressure from the ilia to the sacrum, compressing the SI joints
(2) Clutch-like bracing system
True or false, only either form or force closure is required to stabalize the hip joint?
Both form and force closure are
important in maintaining SI stability.
What are the research fingings of the range of SI joint average flexion and extension?
1 to 8 degrees of average total flexion and extension
What is sacral nutation?
(lumbosacral extension): sacral base moves anterior and inferior
(a) When the lumbosacral region extends, the
sacrum nutates
What is sacral counternutation?
sacral base moves posterior and superior
(a) When the lumbosacral region flexes, the sacrum counternutates.
During pregnancy, how much of an increase of pelvic joint occurs?
Increased pelvic joint mobility (i) 2.5 times increases mobility
What does the sacrum do during delivery?
Sacrum nutates and counternutates during delivery
What is the amount of increase in the symphysis pubis during pregnancy?
4-9mm increased symphysis width
What sacral movement occurs with inhalation?
Counternutation
What sacral movement occurs with expiration?
Sacrum nutates
What do all curves do during inspiration?
All curves decrease during inspiration
What do all curves do during expiration?
All curves decrease
What movement occurs when the ilium is in flexion?
PSIS moves posterior and inferior
(i) Static malposition where ilium is in flexion: PI ilium
What movement occurs when ilium is in extension?
PSIS moves anterior and superior
(i) Static malposition where ilium is in extension: AS ilium
What movement is the SI joint motion named in reference to?
The ilium movement in relation to the sacrum regardless of which bone is moving
What is flexion of the SI joint associated to?
(a) The ilium flexes relative to the sacrum.
(b) The sacrum nutates relative to the ilium.
What is extension of the SI joint associated to?
(a) The ilium extends relative to the sacrum.
(b) The sacrum counternutates relative to the ilium.
What structure is used as a reference point for SI rotation?
PSIS
What does the gonstead listing EX mean in regards to SI rotation?
PSIS moves away from midline
What does the gonstead listing IN mean in regards to SI rotation?
PSIS moves towards midline
What is internal (medial) rotation of ilium known as in gonstead listings?
EX (PSIS moves away from midline)
What is external (lateral) rotation of ilium known as in gonstead listings?
IN (PSIS moving towards the midline)
What is the sacral gyroscopic motion?
(a) Movement occurs during locomotion.
(b) Combination of rotation and translation
(c) Sacral motion is opposite of iliac motion (i) Flexion of ilium sacral nutation
(ii) Extension of ilium sacral counternutation
How do the sacral motions compare during walking?
Sacral motion on one side contrasts with opposite motion on other side during gait
(i) The right side nutates (anterior and inferior movement of the base), while the left side counternutates (posterior and superior movement of the base), and vice versa.
How are the pelvic motions during walking?
One ilium moves opposite to the other during gait
The right ilium flexes while the left ilium extends, and vice versa.
What is the thoracolumbar movement during gait?
(1) Trunk rotation is opposite pelvis rotation
(2) Increased lordosis with hip extension (i.e., toe-off)
(3) Slight momentary scoliosis toward swing side due to pelvic tilt
What is the stabilizer of the pelvis?
(1) Sacrum acts as the keystone in an arch
(a) Supports trunk
(b) Provides locking mechanism for static loads
What is a shock absorber in the pelvis?
(1) Lumbosacral angle influences lumbar curve
- (a) Spinal curves allow the spine to act like a spring.
- (b) Loss of lumbar lordosis increases stress to the spine and lower extremities with consequent functional and degenerative
adaptational changes.
(2) Transfers weight during locomotion
(3) Decreases rotational and lateral flexion stress to lumbar spine (Illi)
(a) In gait, sacrum moves opposite the ilium to reduce stress to the lumbars.
What is the importance of SI function from a chiropractic role?
a) Catch mechanical faults early and may prevent early degenerative changes
b) Pain is often the result of a pathomechanical process rather than a pathological process.
c) Use tools of palpation, observation, x-ray, etc., to identify problems in early stages
(1) approach unique to our profession
Areas to evaluate in posture?
a) Iliac crests
b) PSISs
c) Greater trochanters
d) Gluteal folds
e) Pelvic tilt
What is statically palpated in the pelvis?
Soft tissue
(a) Tenderness and texture of pelvis region muscles and ligaments
(i) Start superficially and work deeper
Bony
(a) Alignment symmetry, tenderness, etc. of bony landmarks
(i) Iliac crests (ii) PSISs (iii) Sacral base, borders and apex (iv) Coccyx
What test is used during standing motion palpation of pelvis?
Gillet’s test
During upper joint gillet’s test where are the Dr’s thumbs placed?
PSIS and sacral tubercle
During upper joint gillet’s test what should occur if the patient flexes the ipsilateral hip?
Flexion occurs
Dr.’s thumbs should approximate as ilium flexes on the sacrum and the PSIS moves posteriorly and inferiorly
During upper joint gillet’s test what should occur if the patient flexes the contralateral hip?
Extension occurs
Dr.’s thumbs should separate as the sacrum counternutates relative to the ilium and the sacral tubercle moves inferiorly
During lower joint gillet’s test where are the Dr’s contact points?
Dr.’s thumbs on sacral tubercle or side of sacral apex & area of PIIS
During lower joint gillet’s test what should occur if the patient flexes the ipsilateral hip?
Flexion occurs
Dr.’s thumbs should separate as the ilium flexes on the sacrum and the PIIS moves inferiorly and anteriorly
During lower joint gillet’s test what should occur if the patient flexes the contralateral hip?
Extension occurs
Sacral contact thumb should move inferiorly relative to the PIIS contact as the sacrum counternutates relative to the ilium
can gillet’s test be performed with both a straight knee and a bent knee?
Yes, but if bent the knee must go above 90 degrees of hip flexion for extension tests when contralateral hip is flexed
What is the P-A glide?
(i) Dr. pushes P-A on the SI joint
(ii) Should have a normal amount of springy movement
What is the sacral push test?
(i) Bilateral thumb contacts across SI joints at level of PSISs
(ii) Pt. extends back toward the Dr.
(iii) Dr.’s thumbtips should move symmetrically forward as the Pt.’s sacral base
moves anterior.
What is the iliac shear (sacral shear)?
(i) Dr. contacts medial PSIS with thumb or thenar and pushes P-A and med. to lat. through the SI joint plane
(ii) Should have a normal amount of springy movement
What is the leg flare or iliac flare test?
(i) Pt. is seated so that knees can move freely.
(ii) Dr. contacts PSISs bilaterally with thumbs
(iii) Pt. moves knees in and out laterally to medially
(iv) Slight med. to lat. movement of the PSISs is normal
What is Piedau’s test?
(i) Dr.’s thumbs on each side of the sacral apex and fingertips on the PSISs
(ii) Pt. bends forward
(iii) Separation of PSISs and sacral apex should occur when the patient flexes forward indicating that the sacral base has moved posteriorly relative to the ilia.
What may be occuring if one PSIS starts inferior and ends up superior?
(a) Hypomobility suspected on that side
(i) SI joint not free to glide; ilium must move further to make up for lack of SI motion
What should occur in the PSISs when the sacral base moves posterior and superior?
Since the sacrum is counternutating (SI extension) the PSISs should separate as The sacrum wedges itself more tightly between the ilia pushing them laterally.
In prone motion palpation of the pelvis, how do you provoke SI joint flexion with one hand?
(a) One-handed contact
(i) Sacral base
(ii) Probably creates more lumbosacral extension than SI flexion
In prone motion palpation of the pelvis, how do you provoke SI joint flexion with two hands?
(b) Two-handed contact
(i) Sacral base & ischial tuberosity
(ii) Better for isolating SI flexion
In prone motion palpation of the pelvis, how do you provoke SI joint extension with two hands?
(b) Two-handed contact
(i) PSIS & sacral apex
(ii) Better for isolating SI extension
In prone motion palpation of the pelvis, how do you provoke SI joint extension with one hand?
(a) One-handed contact
(i) Sacral base
(ii) Probably creates more lumbosacral extension than SI flexion
In side posture motion palpation of the pelvis, how do you provoke SI joint flexion with one hand?
(i) One-handed contact
(a) Ischial tuberosity
In side posture motion palpation of the pelvis, how do you provoke SI joint flexion with two hands?
(ii) Two-handed contact
(a) Ischial tuberosity & ASIS
In side posture motion palpation of the pelvis, how do you provoke SI joint extension with two hands?
(ii) Two-handed contact
(a) PSIS & anterior hip area
In side posture motion palpation of the pelvis, how do you provoke SI joint extension with one hand?
(i) One-handed contact
(a) PSIS
Is the leg length evaluation accurate?
No, There is much debate and speculation about its accuracy and usefulness.
what are some of the issues with leg length evaluation?
It is not an exact science.
(i) It is prone to examiner error.
(ii) It is complicated by a variety of factors.
(iii) Small discrepancies are probably unreliable.
(iv) “Although most studies find prone leg checking reasonably reproducible, there are few data pertaining to its accuracy.”
What is the prevalence of anatomic leg length inequality and what is the average amount?
90 % with an average of 5.2mm
how do you perform a prone leg length evaluation?
Compare heels or malleoli
(i) Malleoli probably more accurate than heels, especially if patient is wearing shoes
(a) May wear unevenly
(b) Heel may not be snugly against bottom of shoe
(ii) Discrepancy here may be functional or anatomic
how do you perform a prone leg length evaluation with knees bent to 90 degrees?
(i) Isolates tibia/fibula length
(ii) If discrepancy still exists: element of tib/fib inequality
(iii) If inequality disappears: functional LLI and/or femoral inequality
how do you perform the supine leg length evaluation?
(i) Isolates tibia/fibula length
(ii) If discrepancy still exists: element of tib/fib inequality
(iii) If inequality disappears: functional LLI and/or femoral inequality
how do you perform the sit-up test leg length evaluation?
Patient sits up from the supine position while Dr. observes leg length
Helps determine if the patient has an anatomic leg length inequality, a functional leg length inequality, or both
What are the 3 possible outcomes from a sit-up test leg length evaluation?
(a) Relative leg length remains the same
(b) Relative leg lengths switch
(c) Any other relative change in leg length
What sit-up test results indicate anatomical inequality?
relative leg lengths remain the same
What sit-up test results indicate functional inequality?
relative leg lengths switch
What sit-up test results indicate both functional & anatomical inequality?
any change other than switching or remaining thesame
What is indicated by relative leg lengths switching in the sit-up test?
functional inequality
What is indicated by relative leg lengths remaining the same in the sit-up test?
anatomical inequality
What is indicated by relative leg lengths becoming less dramatic in the sit-up test?
both anatomic & functional
What is indicated by relative leg lengths becoming more dramatic in the sit-up test?
both anatomic & functional
What is indicated by relative leg lengths going from equal to unequal in the sit-up test?
both anatomic & functional
What is indicated by relative leg lengths going from unequal to equal in the sit-up test?
both anatomic & functional
What LLI results from a flexed ilium in a supine patient?
shorter leg
What LLI results from a extended ilium in a supine patient?
longer leg
What LLI results from a flexed ilium in a seated patient?
longer leg
What LLI results from a extended ilium in a seated patient?
shorter leg
What ilium position leads to a shorter leg in a supine patient?
flexed ilium (PI)
What ilium position leads to a shorter leg in a seated patient?
extended ilium (AS)
What ilium position leads to a longer leg in a supine patient?
extended ilium (AS)
What ilium position leads to a longer leg in a seated patient?
flexed ilium (PI)
What static palpation should be done for pubic symphysis problems?
looking for pain when joint is moved either A-P or
S-I
What motion palpation should be done for pubic symphysis problems?
AP and SI movements plus shearing test
What is the pubic symphysis shearing test?
pt alternates making one leg longer than other; doc evaluates movement at joint
What is Chamberlain’s test?
comparison of pubic symphysis in 2 x-rays with pt
standing on each leg; excess movement indicates instability
What’s a radiographic test for pubic symphysis instability?
Chamberlain’s test; excessive symphysis
movement as patient stands on each leg
What indicates AS ilium in a AP pelvis x-ray?
obturator foramen is shorter, more oblong
What indicates PI ilium in a AP pelvis x-ray?
ilium is taller in flexion
What indicates IN ilium in a AP pelvis x-ray?
ilium is wider
What’s the most accurate x-ray view for leg length evaluation?
scanogram
What is a scanogram?
separate exposures for pt’s hip, knees, ankles; to determine leg length inequality
What is the smart pelvis?
complete compensation by pelvic flex/ext for an anatomical LLI
What is a dumb pelvis?
pelvic flex/ext exaggerates LLI
What’s the usual effect on the PSIS in an extension (AS) ilium malposition?
PSIS is less pronounced
What’s the usual effect on the ASIS in an extension (AS) ilium malposition?
ASIS is low
What’s the usual effect on leg length in an extension (AS) ilium malposition?
extension moves the acetabulum caudally so leg is longer
What’s the usual effect on the sup/inf position of PSIS
and iliac crests in an extension (AS) ilium malposition (pt standing)?
functionally longer leg pushes them higher when pt standing
What’s the usual effect on the sup/inf position of iliac
crests in an extension (AS) ilium malposition (pt prone or supine)?
relatively lower because of shape of ilium
What’s the usual effect on the standing gluteal fold in an extension (AS) ilium malposition?
high gluteal fold due to longer leg
What’s the usual effect on the plumb line in an extension (AS) ilium malposition?
plumb line falls on same side; longer leg causes slight lean to opposite side
What’s the usual effect on lumbar curves in an extension (AS) ilium malposition?
lumbar may be pushed scoliotic to opposite side by unleveling of pelvis
What’s the usual effect on thigh flex/ext in an extension (AS) ilium malposition?
thigh extends further
What’s the usual effect on knee flexion in an extension (AS) ilium malposition?
prone, heel approaches buttock easier
What’s the usual pain pattern in an extension (AS) ilium malposition?
lateral knee & TFL, referral to buttock, posterior thigh, & groin
What is sclerotogenous referral?
referral paint from joint & surrounding tissues
What’s the usual effect on the PSIS in a flexion (PI) ilium malposition?
PSIS more pronounced
What’s the usual effect on the ASIS in a flexion (PI) ilium malposition?
high ASIS
What’s the usual effect on leg length in a flexion (PI) ilium malposition?
short functional leg (lying) from change in
acetabulum position
What’s the usual effect on the sup/inf position of PSIS
and iliac crests in a flexion (PI) ilium malposition (pt standing)?
shorter leg so PSIS and iliac crests are lower when pt standing
What’s the usual effect on the sup/inf position of iliac
crests in a flexion (PI) ilium malposition (pt prone or supine)?
iliac crests are higher when patient lying
What’s the usual effect on the standing gluteal fold in a flexion (PI) ilium malposition?
shorter leg means lower gluteal fold
What’s the usual effect on the plumb line in a flexion (PI) ilium malposition?
plumb line falls on opposite side; shorter leg causes slight lean to same side
What’s the usual effect on lumbar curves in a flexion (PI) ilium malposition?
lumbar may be pushed scoliotic to same side by unleveling of pelvis
What’s the usual effect on thigh flex/ext in a flexion (PI) ilium malposition?
thigh flexes further
What’s the usual effect on knee flexion in a flexion (PI) ilium malposition?
heel approaches buttock less easily
What’s the usual pain pattern in a flexion (PI) ilium malposition?
medial knee, sartorius, referral to buttock,
posterior thigh, groin
What ilium malposition is indicated by a pronounced PSIS?
flexion malposition (PI)
What ilium malposition is indicated by a high ASIS?
flexion malposition (PI)
What ilium malposition is indicated by higher PSIS and iliac crests (pt standing)?
flexion malposition (PI)
What ilium malposition is indicated by lower iliac crests (pt prone or supine)?
As
What ilium malposition is indicated by a higher standing gluteal fold?
flexion malposition (PI)
What ilium malposition is indicated by easier thigh flexion?
flexion malposition (PI)
What ilium malposition is indicated by easier knee flexion?
flexion malposition (PI)
What ilium malposition is indicated by a less pronounced PSIS?
extension malposition (AS)
What ilium malposition is indicated by a low ASIS?
extension malposition (AS)
What ilium malposition is indicated by shorter leg length (lying)?
extension malposition (AS)
What ilium malposition is indicated by lower PSIS and iliac crests (pt standing)?
extension malposition (AS)
What ilium malposition is indicated by higher iliac crests (pt prone or supine)?
extension malposition (AS)
What ilium malposition is indicated by a lower standing gluteal fold?
extension malposition (AS)
What ilium malposition is indicated by easy thigh extension?
extension malposition (AS)
What ilium malposition is indicated by more difficult knee flexion?
extension malposition (AS)
What ilium malposition is indicated by lumbar scoliosis?
same side: PI; opposite side: PI
What ilium malposition is indicated by pain in lateral knee and TFL?
extension malposition (AS)
What ilium malposition is indicated by pain in medial knee & sartorius?
flexion malposition (PI)
What ilium malposition is indicated by pain in buttock, posterior thigh, & groin?
both PI and AS refer here
