Hip and Pelvis

Pelvis

• region of the trunk that lies below the abdomen

• Transmit weight from vertebral column to femur

• Protects organs

• Provides attachment for muscles

Symphysis Pubis

anterior articulation of Hip or Innominate bones

Sacrum at Sacroiliac joint

posterior articulation of Hip or Innominate bones

Acetabulum

Where ilium, ischium, and pubis meets

Ilium

Superior bone of the hip

Ischium

Posterior and inferior bone of the hip

Pubis

anterior and inferior bone of the hip

Puberty

When does the hip bones fuse

Ilium

• upper flattened part of the hip bone.

• hand on the hip

Iliac crest

• prominent superior bony border

• in between the PIIS and ASIS

Wing of Ilium

• a concave/circle like structure of the hip that forms a wing

Auricular Surface

Inner surface of the ilium

Sacrum at Sacroiliac joint

Articulation of the auricular surface

Iliac tuberosity

Located behind the auricular surface

Iliac fossa

large concave inner surface of the ilium

Iliopectineal line

• found in the inner surface of the ilium

• Divides the false pelvis and true pelvis

Iliopubic eminence

• Anterior part of the Iliopectineal line

• Elevation

• Marks the junction of the ilium with the pubis

Ischial tuberosity

• Most inferior part of the ischium

• Bone felt when sitting

Ischial spine

• Separates the greater and lesser sciatic notches

• posterior border of ischium

• Attachement of sacrospinous ligament

Ischial ramus

• connected to the ramus of the pubis

Superior Pubic Rami

• part of pubis that joins with the ilium and ischium at the acetabulum

Inferior pubic rami

• joins the ischial rami

Symphysis pubis

Connection between the two pubic bones anteriorly

Acetabulum

• junction of the ilium, ischium, and pubis

Acetabulofemoral Joint

Joint formed with the articulation of the Head of the Femur to the acetabulum

Greater sciatic notch

Separated from the lesser sciatic notch by the ischial spine

Obturator foramen

• large opening

• bounded by the parts of ischium and pubis

Obturator membrane

• fibrous sheet that almost completely closes the obturator foramen

Obturator canal

• Small gap left in the obturator foramen

• passageway of nerves and vessels

Sacrum

• Consists of 5 vertebrae fused together

• Has a forward concavity

L5 vertebra

Upper border articulation of the Sacrum

Coccyx

Lower border articulation of the sacrum

Sacroiliac joints

Articulation of the sacrum and iliac bones

Sacral promontory

• forward bulge at the anterior and upper margin

• Important landmark when measuring the size of the pelvis

Sacral canal

• formed by the vertebral foramina of the sacrum

• Contains spinal nerves and parts of the spinal cord

Sacral hiatus

Formed due to the failure of laminae of 5th sacral vertebrae to meet

Anterior and posterior sacral foramen

• passageway of nerves in the sacrum

Auricular surface

• Articulates with the innominate bones at the sacroiliac joint

Medial sacral crest

reduced spinous process

Lateral sacral crest

reduced transverse process

Intermediate sacral crests

Represent the fused articular processes

Superior Articular processes

• S1

• Articulates with ingerior articular surface of L5

Sacral Cornua

• S5

• Connected to the cornua of coccyx

• wider in females

• Tilted forward

Lumbosacral angle

• Formed by the forward tilt of of the sacral cornua

coccyx

consists 4 vertebrae fused together

1st Coccygeal vertebrae

• coccyx with a transverse process and a coccygeal cornua

Symphysis pubis and ASIS

Hip bones that lie on the same vertical plane

Symphysis pubis

structure that faces up and back

Sacrum

structure that faces forward and downward

Sacral promontory, iliopectineal line, symphysis pubis

Posterior, lateral, and anterior structures of the pelvic brim

False pelvis

• Bigger, located above the brim

• Lumbar vertebrae, iliac fossa, anterior abdominal wall

• Supports abdominal contents

• Guides the fetus during labor

True pelvis

• Smaller, located below the brim

• Has an inlet, diamond-shaped outlet, cavity

Gynecoid

Typical female pelvis

Android

Typical male pelvis

Anthropoid

long, narrow, oval-shaped

Platypelloid

Kidney-shaped, broad and flat. Wide and narrow inlet

Synovial Joint

What type of joint is the sacroiliac joint

Sacrum and Iliac

Articulation of the sacroiliac joint

Anterior and Posterior Sacroiliac ligament

Ligaments of the sacroiliac joint

Sacrotuberous and sacrospinous ligaments

• accessory ligaments of the sacroiliac joint

• adds stability to the joint

• Converts greater and lesser sciatic notches into FORAMINA

Forward tilting

____ of the sacral promontory is prevented to stabilize sacrum on the hip bone

Lumbosacral joint

joined by the intervertebral disk, anterior and posterior ligaments, ligamenta flava, interspinous and supraspinous

L5 and S1

articulation of the lumbrosacral joint

Iliolumbar ligament

• from L5 to the ilium

• limits flexion, extension, and lateral flexion

Lateral lumbosacral ligament

From L5 to sacrum

Sacrococcygeal joint

• cartilaginous joint

• articulates S5 and Coccyx

Symphysis Pubis

• cartilaginous joint

• its ligaments soften during pregnancy

Superior pubic ligament

• ligament of the symphysis pubis that strengthens it in the anterosuperior aspect

Inferior pubic ligament

• ligament of the symphysis pubis that strengthens it in inferiorly

Femur

• articulates with the acetabulum to form the hip joint

• articulates with the tibia and patella to form the knee joint

Head of the femur

• articulates with the acetabulum

• is 2/3 of a sphere

Fovea capitis

• small depression at the center of the head

• attachment of the ligament of the head

Gluteal tuberosity

attachment of the gluteus maximus muscle

Acetabular labrum

• deepens the cavity of acetabulum

• adds to the joint’s depth and stablity

Hip joint

• synovial, ball and socket

• articulates at the head of the femur and the acetabulum

Iliofemoral ligament

• strong, inverted Y-shaped ligament

• prevents overextension during standing

• limits extension and lateral rotation

Pubofemoral ligament

• Triangular

• Limits extension, abduction, and external rotation

Ischiofemoral ligament

• Spiral

• limits extension and internal/medial rotation

Transverse acetabular ligament

• formed by the acetabular labrum as it bridges across the acetabular notch

• converts the notch into a tunnel

Ligament of the head of the femur

• flat and triangular

• limits adduction

• conduit for blood supply and nerves

Angle of inclination

• femur shaft angles medially to align the femoral head and knee

• neck-shaft angle

150

• average angle of inclination

coxa valga

• excessive angle of inclination

• beyond 150

Coxa vara

• angle of inclination is less than 125

Angle of torsion

• medial twist of the femur

• line between condyles ais medially rotated relative to the line of femoral head and neck

15

normal angle of torsion

Femoral anterversion

angle is greater than normal

Femoral retroversion

angle is lesser than normal

Counternutation

butt out motion, ASIS moves inferiorly

nutation

butt in, ASIS moves superiorly

Lateral tilt

left or right pelvis moving up in frontal plane

Rotation

• anterior or posterior motion of pelvis in transverse plane

Muscles of the Pelvic Walls

POLC

• piriformis

• obturator internus

• levator ani

• coccygeus

Muscles of the anterior compartment of thigh

SIPP Quads

• sartorius

• iliacus

• psoas

• pectineus

• quadriceps femoris

Muscles of medial compartment of the thigh

• Gracilis

• adductor longus

• adductor brecis

• adductor magnus

• obturator externus

Muscles of the posterior compartment of the thigh

BSSA

• Biceps femoris

• semitendinosus

• semimembranosus

Muscles of the gluteal region

• Gluteus

• Tensor fascia latae

• piriformis

• obturator internus

• gemellus

• quadratus femoris

Anterior compartment

• performs hip flexion

Posterior compartment

• performs hip extension

Lateral muscles

• performs hip abduction