1. Pelvis Stuart Williams D.O. Chairman & Associate Professor
Osteopathic Manipulative Medicine

2. Objectives 04/08/2013 10:00 -11:00 PPC/OMM pelvis Williams
Recall the structural anatomy of the pelvis
Describe the functional anatomy of the pelvis
Explain the difference between iliosacral and sacroilial motion
Recognize common somatic dysfunctions of the pelvis and how to incorporate these into a differential diagnosis.
Explain the biomechanics of the pelvis including the axes of motion
Recall the lateralizing tests for pelvic somatic dysfunction. Understand the use of anterior & posterior landmarks to diagnose pelvic somatic dysfunctions
Name potential diagnoses of pelvic somatic dysfunctions. Understand the difference between physiologic and non-physiologic somatic dysfunction
Recall anatomy of Pelvis

3. Reading Foundations of Osteopathic Medicine, 3rd Ed:
“Pelvis and Sacrum” P

4. The Pelvis Functionally consists of three bones: - the innominates
ilium
ischium
pubis
- the sacrum,
And three joints
- the sacroiliac joints (two of them)
- the pubis symphysis  moves on a transverse axis

5. Features in Trauma

6. Most common way to get a pubic shear is because the innominates are so rotated that it pulls the pub w it, but you CAN get isolated pubic shears (usually from trauma)

8. Inferior Lateral Angle
Sacrum
Base of Sacrum
Sacral
Promontory
Superior Articular
Processes
ALA
Hiatus- failure of closure of the 5th sacral vertebral lamina
Ganglion Impar- where right and left sympathetic chains join is on the anterior surface of the coccyx
Median Sacral Crest
Apex of Sacrum
Sacral
Foramina
Sacral Hiatus
Inferior Lateral Angle

9. Osteology/Articulations
Sacrum articulates with
The 5th lumbar superiorly
The coccyx inferiorly
Two pelvic( innominate bones )through the “L” shaped sacroiliac articulation

10. Lumbarization Sacralization S1 S2 S3 S4 S5
Occurs in small percentage of people (grey p. 326)
Partial Lumbarization – pseudoarthrodial area created. (circle)
batwing deformity
Complete Lumbarization – one fewer sacral vertebrae (dots)
The dorsal wall to the Sacral Canal may be variably deficient d/t imperfect development
Orientation of Zygapophysial Lumbosacral joints display wide variation (20 to 90 degrees)
Commonly Have low back pain  increased ferguson’s angle S3
Sacralization S4 S5

11. Sacroiliac Joint
The SI joint functions to redirect force from the lower extremities to the rest of the body.
Movement in the SI joints is small, but measurable in both rotation (~1.8°) and translation (~1mm).
No muscles are directly responsible for this motion.
Force is accommodated by the irregular surface of the joint and LARGE posterior ligaments.
This has treatment implications, we have to use the legs as levers.
45 degree angle from the AP axis has diagnostic and treatment implications

12. Pubic Symphysis
Motion at each pubic ramus is a PHYSIOLOGIC rotation about a transverse axis.
Synarthrosis- intrapubic disc that is covered with hyaline. Fibrocartilagenous joint.
When walking, look at iliosacral motion (the ilium on the sacrum)
When seated look at sacroiliac motion (the sacrum on the ilium)

13. Sacroiliac Joints
Vertebral disc are thicker in lower lumbar to support weight
Know that piriformis attaches to the greater trochanter
Know that the iliopsoas attaches to the lesser trochanter  strongest flexor muscle in the body

14. Toward Greater Trochanter
Toward ASIS
Sacroiliac
Joint
The articular surfaces of the upper and lower poles are not the same size
This leads to different qualities of motion during diagnosis (don’t compare upper pole motion to lower pole motion)
The plane of the upper and lower poles are approximately 90 degrees to one another- look at the prior slide to see how this is effective at “locking the joint”
The SI joint is concave on the sacrum.
Final fusion not until mid 20s
Therefore, the SI joints may not be bilaterally symmetrical d/t developmental differences among individuals
Toward Greater Trochanter
These joints are not present at birth-
they develop functionally
They are not totally symmetric

15. Lumbosacral Junction
Ferguson’s Angle as measured from the horizontal should be about 35 degrees.
35º
Used on lateral X-ray film to determine hyper-lordosis of lumbar spine.
What would happen if the sacral base were anterior or posterior, or highly flexible? Why is this important?
Imagine trying to hold that force on a ninety-degree angle.
If greater angle  more lordosis
If lesser angle  flattened lordosis

16. Ligaments

17. Ligamentous Attachments of the Sacrum
Suspended between the innominates by three true ligaments:
Anterior Sacroiliac
Interosseous Sacroiliac
Posterior Sacroiliac
And three accessory ligaments:
Sacrotuberous
Goes between the ILA and the ischial tuberosity
Sacrospinous
Iliolumbar (L4 and 5, connects to lateral thigh too)
Sacrotuberous: PSIS, coccyx and lower part of sacrum to Ischial Tuberosity

18. Ligaments Iliolumbar ligaments prevent L5 from sliding anterior.
It also blends with the anterior sacroiliac to INTEGRATE SI joint mechanics. This allows smooth symmetry of motion.
Interosseous ligaments blend the non-articular surfaces of the SI joint.
In a weight bearing position the sacral base would move anteriorly if it wasn’t restrained.
Iliolumbar is sensitive to pain in conditions that cause sacral instability
Sacrotuberous and Sacrospinous ligaments restrain anterior motion of the sacrum by resisting posterior rocking of the apex.

19. Ligaments Interosseous: not shown
Can get sclerotomal pain from these ligaments

20. Ligaments- Part II
Sacrotuberous and Sacrospinous ligaments restrain anterior motion of the sacrum by resisting posterior rocking of the apex
The sacroiliac and the iliolumbar ligaments prevent the sacral base from rocking anteriorly.
Posterior, Lateral and Axial Rotation are prevented by a combination of the anterior, posterior and interosseous ligaments.

22. Out of all the ligaments here the iliofemoral ligament (ligament of bigalow?) is the strongest

23. Iliopsoas Functional Anatomy
Concentric contraction results in hip flexion & ext rotation.
Function of this muscle is to eccentrically & dynamically stabilize hip extension & internal rotation in bipedal ambulation.
Dysfunction can lead to innominant rotations & gluteus inhibition.
Thomas test checks for this

24. Muscular Attachments of the Sacrum
Muscles:
Gluteus Maximus
Longissimus Thoracis
Iliocostalis Lumborum
Multifidus
Ligaments:
Sacroiliac
Post. Sacrococcygeus
mulitfidus
Gluteus Maximus
Erector
spinea

25. Sacrum Anterior Aspect
Muscles:
Iliacus
Piriformis
Coccygeus
Ligaments:
Sacrospinous
Sacrotuberous
Ant. Sacrococcygeus
Anterior Sacroiliac
The piriformis attached to the lateral anterior sacrum, goes through the sciatic notch and attached to the greater trochanter. The sciatic nerve passes inferior to the piriformis (although) there is great variation in this.
External rotation
If a tight piriformis, a pt will not be able to internally rotate well bc will be stuck in external rotation

26. A-P View P-A View Psoas Iliacus Quadratus Lumborum
Iliopsoas passes from the upper lumbar vertebrae, over the pelvic rim, and to the lesser trochanter like a “violin string”
Quadratus Lumborum arises from aponeurotic fibers of the iliolumbar ligament, origin from the last rib and inserts on the TP’s of L1-L4, and the posterior third of the iliac crest (maybe the iliolumbar ligament
Psoas
Iliacus
Quadratus Lumborum

27. Piriformis Gemellus Superior Obturator Internus Gemellus Inferior
Obturator Externus
Quadratus Femoris
Gluteus Maximus
Gluteus Medius
Tensor Fascia Lata
Semitendinosus
Semimembranosus
Biceps Femoris
External hip roators
Iliotibial band mm
Hamstrings
Anterior AIIS attachments: quadriceps: rectus femoris, vastus lateralis, medius and intermedius
(ASIS sartorius mm)

28. Pelvic Floor Levator Ani Muscles: Puborectalis Pubococcygeus
Iliococcygeus
Coccygeus
These muscles constitute the pelvic diaphragm. They do have rhythmic contractions like the respiratory diaphragm, but when relaxed they will contract with the diaphragm. In disease states of the pelvis, respiratory mechanics are an important consideration.
Remember in thorax  want to maintain a – pressure gradient, in abdomen  maintain a + pressure gradient

29. Autonomic Innervation: Pelvic Viscera
(T10-L2)
Sympathetic
Parasympathetic
(S2-S4)
Be aware the sympathetic innervation of the lower legs is from T11-L2.

30. Nervous System Close relationships between the nerves and the sacrum.
Pain can be secondary to m/s involvement or visceral or BOTH!

31. Landmarks

32. Landmarks of the Pelvis
Patient Standing Iliac crest level PSIS Greater trochanters Patient Supine ASIS Pubic symphysis Pubic tubercles Medial malleoli
Patient Prone PSIS Sacral sulcus Sacral base Inferior lateral angle Sacortuberous lig. Ischial tuberosity Iliac crest Piriformis muscle Iliolumbar ligament

33. Sacral
base
Inferior
Lateral
angle

34. Sacral Axes Multiple axes of motion: Transverse (3) Vertical A/P
Superior S1 (TP)
Middle S2 (TP)
Inferior S3 (TP)
Vertical
A/P
Oblique (2)
Left
Right
Flexion occurs when the Sacral Base moves anterior, Extension when it occurs moves posterior on middle transverse axis.
Superior Transverse axis: at level of second sacral segment, posterior to the SI joint in the SP area. (“respiratory axis”)
Middle Transverse axis: at anterior convexity of the upper & lower limbs of SI joint. (sacral flexion & extension)
Inferior Transverse axis: at posterior-inferior portion of the inferior limb of the SI joint. (anterior & posterior innominate rotation)

35. SACRAL ANATOMIC AXIS Transverse axis
Superior: the cranial primary respiratory mechanism creates motion around this axis
Middle: sacral base anterior and posterior (FB/BB) occur around this axis
Inferior: the innominates rotate around this axis
Reference Foundations p
Know this

36. SACRAL PHYSIOLOGIC AXIS
Oblique: both left and right oblique axes are named for the superior pole
Sagittal: includes both mid-sagittal and an infinite number of parasagittal axes
Horizontal: functional axis of sacral flexion/extension occur around this
axis (analogous to the middle
transverse axis above)

37. SACRAL MECHANICS Physiologic diagnoses of the sacrum occur in
neutral and non-neutral mechanics:

38. Neutral Mechanics a.k.a. Left rotation on a Left Oblique Axis
Forward Torsion
In neutral mechanics, the sacrum rotates in the same direction as the oblique axis (left rotation on a left oblique axis).
(all three are equivalent terms!!)

39. Non-neutral Mechanics a.k.a.
Right rotation on a Left Oblique Axis
Backward Torsion
In non-neutral mechanics, the sacrum rotates in the opposite direction of the oblique axis (right rotation on a left oblique axis).
(all three are equivalent terms!!)

40. Walking Cycle and the Pelvis
Double support
Double support
Single limb support
Single limb support
(opposite side)
Know this slide well
Know your pressure is more on the lateral aspect of your foot
Heel strike Flat foot Mid-stance Heel off Toe off Mid swing Heel strike

41. Pelvic Mechanics During the Walking Cycle
Walking induces (reversible) neutral oblique axis mechanics in the sacrum with every step e.g., right rotation on right oblique axis, then left on left oblique axis.
It induces side bending of the lumbar spine towards the side of the weight bearing leg.
It also causes posterior rotation of the weight bearing ilium and anterior rotation of the non-weight bearing ilium.
Second point- this means that rotation will be AWAY from the side of the weight bearing cycle. We would expect this in order to preserve physiologic axis.

42. Gait Cycle To move the right foot - the body must shift to the left.
A N SLRR motion occurs in the L spine
A left oblique axis occurs at sacrum.
Sacrum rotates left on oblique axis.
Right quadriceps tighten and the right innominate rotates anteriorly.
Right hamstrings contract.
Hamstrings pull right innominate into a relative posterior position.
Pubic sympyhsis provides a transverse axis.
Heel strikes the ground.
Left leg thrusts body forward.
Center of gravity shifts forward & to the right.
Gait Cycle

43. Walking Cycle

44. Anterior Anatomical Landmarks

45. Posterior Anatomical Landmarks

46. Movement of the Innominates
Innominates rotate around the inferior transverse axis of the sacrum
Located at inferior limb of sacroiliac joint
This is iliosacral motion, not sacroiliac motion
S: pubic symphysis
H: acetabulum
X: inferior transverse axis

47. Possible Somatic Dysfunctions of Innominates
Anterior Innominate Rotation( Innominate Anterior)
Posterior Innominate Rotation(Innominate Posterior)
Upslipped Innominate (Superior Innominate Shear)
Non-physiologic SD, traumatic etiology
Not involved in inferior transverse axis mechanics
Downslipped Innominate (Inferior Innominate Shear)
Non-physiologic SD, Rare
Innominate Inflare/ Innominate Outflare
Innominates rotate around respective vertical axes
Non physiologic means there isn’t an axis there

48. Once you have lateralized the patient to one side, all other findings are named in relation to what is found on the restricted side
Mark your diagnostic worksheet accordingly

49. Lateralization of the Pelvis
Seated Flexion
ASIS Compression
Don’t forget to reset the pelvis!
Standing Flexion
Thumbs under PSIS!
Palms cupping ASISs, force vector is posteromedial

50. Supine Diagnosis Put thumbs horizontally under the ASIS’s
Are they level? Is the lateralized side inferior or superior relative to the non-lateralized side?
correct
incorrect

51. Supine Diagnosis visualize & palpate: do they agree?

52. Supine Diagnosis - Inflare/Outflare
Visualize a line from each ASIS to umbilicus
Is lateralized side relatively further (outflare) or closer (inflare) to umbilicus? L R

53. Supine Diagnosis
Place thumbs under medial malleoli
Apply slight inferior traction
Is the lateralized side inferior or superior relative to the non-lateralized side?
Malleoli are mixed landmarks, but can alert the operator to stresses placed on pelvis, leg, and ankle, or to functional/anatomical short leg
Can be used to help confirm diagnosis L
correct
incorrect

54. Prone Diagnosis Place thumbs horizontally under the PSIS’s
Are they level? Is the lateralized side inferior or superior relative to the non-lateralized side?
There is a “dimple” under the PSIS: place thumbs horizontally
Correct
Incorrect

55. Prone Diagnosis L

56. Prone Diagnosis Ischiotuberosity L
Can also use heels. Will show in lab. This is a time to exhibit professionalism.

57. Innominate Diagnoses:
Left Anterior Rotation
Findings
Left ASIS relatively inferior
Left PSIS relatively superior
S: pubic symphysis
H: acetabulum
X: inferior transverse axis

58. Innominate Diagnoses:
Left Posterior Rotation
Findings
Left ASIS relatively superior
Left PSIS relatively inferior
S: pubic symphysis
H: acetabulum
X: inferior transverse axis

59. Pubic Symphysis Diagnosis
Patient is supine
Explain to your patient what you are going to do
Ask male patients if they need to adjust
Using the heel of your hand, start at the umbilicus and slide inferiorly with gentle pressure until you reach the pubic symphysis

60. Pubic Symphysis Diagnosis
Place your fingers on the superior aspect of the pubic symphysis to diagnose sup./inf.
Place your fingers on the anterior aspect of the pubic symphysis to diagnose ant./post. L L

61. Pubic Symphysis Somatic Dysfunctions
Pubic Symphysis Superior/Inferior Shear
May often follow innominate SD, or be SD by itself (rare)
Can follow innom ant/post rotation, up/down slipped innom.
Can follow sacral shear
Common in obstetrical patients due to relaxin
Pubic Symphysis Anterior/Posterior Shear
Relatively rare, usually caused by trauma

62. Innominate Diagnoses:
Left Inferior Pubic Shear
Findings
Left ASIS relatively inferior
Left PSIS relatively superior
Usually has an associated L anteriorly rotated innominate.
S: pubic symphysis
H: acetabulum
X: inferior transverse axis

63. Innominate Diagnoses:
Left Superior Pubic Shear
Findings
Left ASIS relatively superior
Left PSIS relatively inferior
Usually associated with a posteriorly rotated innominate if physiologic.
S: pubic symphysis
H: acetabulum
X: inferior transverse axis

64. Innominate Diagnoses:
Left Upslipped Innominate
Findings
Left ASIS relatively superior
Left PSIS relatively superior
Nonphysiologic.
No axis!
Symphysis and Ischial tuberosity could also be superior in more severe cases.
S: pubic symphysis
H: acetabulum
X: inferior transverse axis

65. Innominate Inflare/Outflare Somatic Dysfunction
Lateralized ASIS is closer to the umbilicus than the non-lateralized side
i.e., with a left inflare, there is a shorter distance between the umbilicus and left ASIS than the right ASIS
Outflare:
Lateralized ASIS is further away from the umbilicus than the non-lateralized side
i.e., with a left outflare, there is a longer distance between the umbilicus and left ASIS than the right ASIS
Innominate inflare/outflare somatic dysfunction is not involved in inferior transverse axis mechanics
It occurs about a vertical axis

66. Left Outflare

67. Innominate Diagnosis Checklist
Lateralization of Pelvis (at least 2/3)
Standing/Seated Flexion Test
ASIS Compression
Supine:
ASIS (superior/inferior)
Inflare/Outflare
Pubic Symphysis (superior/inferior, anterior/posterior)
Medial Malleoli (superior/inferior)
Prone:
PSIS (superior/inferior)

68. Right Anterior Innominate

69. Right Posterior Innominate

70. Left Superior Pubic Shear

71. Right Upslipped