1. “The Human Appendicular Skeletal System”
Laboratory Exercise 6
“The Human Appendicular Skeletal System”

2. Human Skeletal System – Appendicular
In this exercise, you will identify bones of the appendicular skeleton, identify the surface markings of individual bones and learn their significance, and compare and contrast the male and female pelvis.
These terms should be familiar to you: pectoral girdle, upper limbs, pelvic girdle, lower limbs, clavicles, scapulae, coxal bones, humerus, radius, ulna, carpals, metacarpals, phalanges, femur, tibia, patella, fibula, metatarsals, phalanges.
This laboratory exercise correlates with Chapter 8 of your textbook.

3. What procedures are we doing?
Observe the pectoral girdle
Observe the upper extremity
Observe the pelvic girdle
Observe the lower extremity
Examine different bone markings

4. Resources available…
Anatomy and Physiology Laboratory Study Pages; submenu: Skeletal

5. Laboratory Lecture

6. An Introduction to the Appendicular Skeleton
The Appendicular Skeleton has 126 bones
It allows us to move and manipulate objects
It includes
The limbs (arms or legs)
The girdles (pectoral or pelvic)

7. The Appendicular Skeleton7

8. 8-1 The Pectoral Girdle
The Pectoral Girdle is also called the shoulder girdle
It connects the arms to the body
Positions the shoulders
Provides a base for arm movement
Each pectoral girdle consists of
Clavicle
Scapulae
The clavicle connects with the axial skeleton only at the manubrium of the sternum (the scapula is free)*

9. 8-2 The Upper Limbs The upper limbs consist of:
Humerus (brachium or arm)
Radius & Ulna (antebrachium or forearm)
Carpals (wrist)
Metacarpals (hand)
Phalanges (fingers and thumb)

10. 8-3 The Pelvic Girdle
The pelvic girdle is composed of three coxal bones (hip bones or pelvic bones or ossa coxae)
Ilium
Ischium
Pubis
They are strong bones, meant to bear body weight and the stress of movement
They articulate with each other and elements of the vertebral column (sacrum & coccyx) to form a ring structure, called the pelvis, that fuses by age 15
The pelvis is divided into the true (encloses pelvic cavity) and false (inferior abdominal cavity) regions by the pelvic brim

13. Sex Differences in the Human Skeleton
MALE
FEMALE
PELVIS
Narrower, rougher, more robust
General Appearance
Broader, smoother, less robust
More vertical; extends farther superior to sacroiliac joint
Ilium
Less vertical; less extension superior to sacral articulation
Long, narrow triangle with pronounced sacral curvature
Sacrum
Broad, short triangle with less sacral curvature
Deeper
Iliac fossa
Shallower
Narrower, heart shaped
Pelvic inlet
Open, circular shaped
Narrow
Pelvic outlet
Enlarged
Points anteriorly
Coccyx
Points inferiorly
Directed laterally
Acetabulum
Faces slightly anteriorly
Oval
Obturator foramen
Triangular
Under 90
Pubic angle
100º
or more
OTHER
Read about Relaxin!
Heavier
Bone weight
Lighter
More prominent
Bone markings
Less prominent

14. 8-4 The Lower Limbs The lower limbs bear weight and facilitate motion
Of note, the thigh is the upper leg. The leg is the lower leg
Lower limb bones include:
Femur (thigh)
Patella (kneecap)
Tibia and fibula (leg)
Tarsals (ankle)
Metatarsals (foot)
Phalanges (toes)

15. Arches of the Feet
Arches transfer weight from one part of the foot to another
The shape of the arch is maintained by foot bones and held in place by tendons and ligaments
They function as a spring and provide leverage when walking, protecting blood vessels and nerves of the sole of the foot

16. Allows for weight transfer depending on the position of the foot
The longitudinal arch
Allows for weight transfer depending on the position of the foot
The transverse arch
Runs perpendicular to the longitudinal arches. It is formed by the
difference in curvature between the medial and lateral borders of
the foot
Dorsiflexion: flexion at ankle
“dig in your heels”
Plantar flexion: ankle extension
“stand on your tippy-toes”