Anatomy and Physiology
Chapter 6 DRO
The Human Pelvic Girdle and Leg:
The Pelvis:
Pelvis Girdle:
The Coxal Bone:
Name:
Period:
*Consists of two bones (coxal bones) connected by fibrous cartilage (pubis
symphysis)
*Each coxal bone itself is the result of the fusion of three bones (the ilium, ischium,
pubis)
*Sacroiliac joint = articulation of hip bone with sacrum
*Because of weight bearing and locomotion, the bone of the pelvic girdle are
*more massive than the pectoral girdle
*more firmly attached to the axial skeleton
*Hip joint = femur and acetabulum of coxal bone
*TWO coxal bones
*Each hip bone results from the fusion of three separate components which fuse together:
1. The ilium
2. The ischium
3. Pubis symphisis
*The ilium, ischium and pubis together form a deep socket called the acetabulum which articulates with
the head of the femur
Ilium:
*Largest, most superior component of the coxal bone
*Broad curved surface provides large surface area for attachment of muscles, tendons and ligaments
*Iliac crest = “the hip”
*Iliac spine can be seen is especially thin people
*Iliac crest (superior)
*ASIS = anterior superior iliac spine
*PSIS = posterior superior iliac spine
*Iliac fossa = wide depression
*Ala = the other side of the iliac fossa
*Arcuate line (medial)
*Sacral articulation
*Anterior, posterior and superior gluteal lines (attachments for gulteal muscles)
*Greater sciatic notch
Ischium:
*Most Inferior and strongest part of the coxal bone
*Ischial tuberosity (inferior surface) supports the body’s weight when sitting; attachment site
for hamstrings
*Ischial Spine: separates the greater and lesser sciatic notch.
*Obturator foramen – opening mostly covered by a membrane which attaches to obturator
muscle, also serves as passageway for nerves and blood vessels from abdominal cavity to
lower limbs
*Lesser Sciatic Notch- smooth notch covered with cartilage-attachment for tendons
Pubis:
Acetabulum:
*Most anterior part of the coxal bone
*Also called pubic bone
*Latin for little cup of vinegar
*Deep socket formed were the ilium, ischium and pubis bones articulate
*Accepts the head of the femur to form the hip joint
*Ball and socket joint
1. Ilium:
2. Ischium:
3. Pubis:
4. Sacrum:
5. Symphysis:
6. Obturator
foramen:
7. Acetabulum:
8. Iliac crest:
9. Sacroiliac joint:
10. Subpubic angle:
11. Anterior superior
iliac spine:
12. Posterior
superior iliac spine
13. Iliac fossa
(medial)
14. Ala (lateral)
15. Arcuate line
16. Ischial spine
17. Greater Sciatic
notch:
18. Lesser Sciatic
notch:
General:
*Differences in shape and size result from variations in body size and muscle mass
*Female pelvis: Smoother, lighter in mass and less prominent markings
*Some differences are adaptations for child-bearing (to support the weight of the fetus
and to ease passage of baby during birth)
*Female pelvis: broad, low pelvis, larger pelvic outlet, broader pubic angle
1. Pelvic Weight
*Bones of the pelvis are lighter and thinner in females and thicker and heavier in
males
2. Pelvic Inlet
3. Pelvic Outlet
4. Sub pubic angle
*Female pelvic inlet is rounded and oval shaped compared to the heart shaped
male pelvic inlet
*Pelvic outlet is rounded and larger compared to a shorter pelvic outlet in males
*females is greater than 80 degrees, males less than 70 degrees
5. Distance between
ischial spines
*the distance between ischial spines in females is greater than that of males
6. Lesser Pelvic
Cavity
*Lesser pelvic cavity is shorter and wider in females and longer and more
narrow in males
Male vs. Female
pelvis
1. Pelvic Inlet
2. Pelvic Outlet
3. Sub Pubic
Angle
4. Distance
between
Ischial
Spines
Figure A.
Your Turn:
Male vs Female
Figure B.
Make an argument
for which pelvis is
male and which one
is female. Use the
proper terminology
to support your
argument.
The Femur:
Bones of the Lower
Limbs:
Femur:
*Thigh = femur
*Leg = tibia and fibula
*Foot = tarsals, metatarsals and phalanges
*Heaviest strongest bone in the body
*Slants medially to join with the leg bones which brings the knees in line with the center of
gravity
*Structures to know: greater and lesser trochanters, intertrochanteric crest, gluteal tuberosity,
lateral and medial condyles, intercondylar fossa (notch), patellar surface
Proximal Extremity:
Head:
*Head- articulates with the acetabulum
Neck:
*Neck- weakest part of the femur- common area for fractures
Greater
Trochanter:
*Greater trochanter - insertion of gluteus muscles
Lesser
Trochanter:
Distal Extremity:
Lateral and
Medial Epicondyles:
Lateral and Medial
Condyles
*Lesser trochanter - insertion of psoas muscle
*Epicondyles- attachment of ligaments and muscles
*Trochlear groove- articulates with the patella
Condyles (lateral and medial) articulate with tibia and distribute body weight to the knee
Intercondylar
fossa:
1. Head:
2. Neck:
3. Greater
Trochanter:
4. Lesser
Trochanter:
5. Lateral
Epicondyle:
6. Medial
Epicondyle:
7. Lateral Condyle:
8. Medial Condyle:
9. Intercondylar
fossa:
10. Petellar groove:
*separates the condyles of the femur- attaches the cruciate ligaments
Tibia and Fibula:
The Leg:
Proximal Extremity:
1. Medial condyle:
2. Lateral condyle:
Distal Extremity:
3. Medial
malleolus:
4. Proxiaml
Articulation:
*Two bones connected by interosseous membrane
*Tibia (shin) = larger, medial bone
*Forms knee joint with femur
*Medial malleolus forms the ankle
*Fibula = thin and stick-like
*No part in forming knee joint
*lateral malleolus forms the ankle
*Structures to know: medial and lateral condyles, intercondylar eminence, tibial
tuberosity, medial and lateral malleolus, tibiofibular joints, anterior crest,
Fibula:
Proximal Extremity:
1. Head:
2. Lateral
malleolus:
3. Distal
Articulation:
Bones of the Ankle and Foot:
The Foot:
*Two important functions:
*Support of body weight
*Serves as a lever to propel our body forward
*Tarsals (7 bones)
*Calcaneous = heel bone
*Talus = “ankle” lies between the tibia and the calcaneous
*Metatarsals (5 bones) = sole of foot
*Phalanges (14 bones) = toes
*Each toe has 3 phalanges except the big toe which has 2
1. Tarsals
a. calcaneus
b. talus
c. navicular
d. cuboid
e. 1st cuniform
f. 2nd cuniform
g. 3rd cuniform
2. Metatarsals
3. Phalanges