VIII. Pectoral Girdle

1
VIII. Pectoral Girdle Upper Extremity -
Articulation between upper extremities and axial
skeleton -Shoulder joints are weak joints

• Pectoral Girdle
• 1. Clavicle collarbone
• - Long slender bone with a double curve
• - Anterior articulation forms the
  sternoclavicular joint
• - Lateral articulation is acromioclavicular
  joint

2
2. Scapula shoulder blade - Spine sharp
diagonal ridge - Acromion end of the spine -
Glenoid cavity depression inferior to the
acromion and articulates with the humerus -
Coracoid process projection for muscle
attachment
3
B. Upper Extremity 60 bones

• Humerus
• Longest, largest bone of the upper extremity
• Articulates with the scapula and radius and ulna

a. Head proximal end b. Body shaft, deltoid
tuberosity attachment for the deltoid c.
Capitulum rounded knob at the distal end d.
Radial fossa depression for the head of the
radius (thumb side) e. Coronoid fossa receives
the ulna when the arm is flexed f. Olecranon
fossa receives the ulna when the are is
extended
4

• 2. Radius - Lateral bone (thumb side) the
  proximal end articulates with the capitulum and
  radial notch of the ulna
• Radial tuberosity attachment of the bicpes
  brachii muscle
• Styloid process distal end

3. Ulna medial bone of the forearm a.
Olecranon process proximal end b. Trochlear
notch curved area between the olecranon and
coronoid process c. Styloid process distal end
5
4. Carpals 8 small bones of the wrist that are
connected by ligaments a. top row lateral to
medial scaphoid, lunate, triquetral,
pisiform b. bottom row trapezium, trapezoid,
capitate, hamate
6
5. Metacarpals palm of hand, made of 5
bones a. numbered 1-5, starting with the
thumb b. consists of a base, shaft and head
(proximal to distal) c. heads make up the
knuckles 6. Phalanges fingers, each hand has 14
bones a. A single bone is called phalanx, made
up of a base, shaft and head b. The thumb
(pollex) has 2 phalanx proximal and distal c.
The fingers have 3 phalanx proximal, middle,
distal (index, middle, ring, little)
7
IX. Pelvic Girdle Lower Extremity A. Pelvic
girdle formed by the 2 coxal (hip) bones -
functions for weight-bearing - connected by
fibrocartilaginous joints called the pubic
symphysis - consists of the ilium, ischium
(coxae), pubic and sacrum
8
1. Ilium superior portion 2. Ischium
posterior portion and inferior 3. Pubis
anterior and inferior, these bones are separate
in a newborn - acetabulum deep fossa for
articulation with the head of the femur formed by
the fusion of three bones - iliac crest upper
border of the ilium, the front projections are
the superior and inferior iliac spines -
obturator foramen opening formed by the fusion
of the ischium and the pubis
9

• B. Lower extremity Leg
• Femur longest and heaviest bone in the body
• a. Shaft bows medially to align the knee joints
  to the center of gravity
• b. Head articulates with the acetabulum
• c. Has a medial and lateral condyle
• d. Greater trochanter is the projection on the
  outer side
• e. Linea aspera is the rough vertical ridge for
  muscle attachment

10
2. Patella knee cap a. small, triangular
sesamoid bone b. embedded in the patellar
tendon of the quadriceps 3. Tibia shinbone
a. weight bearing bone of the lower leg b.
articulates with the femur, the fibula and the
tarsals c. has a medial and lateral condyle
(superior) d. the medial malleolus is on the
distal end and articulates with tarsals and the
fibular notch e. tibial tuberosity is the
attachment point of the patellar ligament
(tendon)
11
4. Fibula small bone parallel to the tibia
a. articulates proximally with the lateral
condyle of the tibia b. the lateral
malleolus articulates distally with the ankle
c. non weight-bearing
12
5. Tarsals 7 bones a. Talus is posterior
and bears the entire weight initially
articulates with the tibia and fibula b.
Calcaneous is also posterior and receives 50 of
the weight c. Cuboid, navicular and three
cunieform bones are anterior and receive the
other 50 of the weight
13
6. Metatarsals 5 bones a. Numbered from
1-5, medial to lateral b. Also have a base,
shaft and head c. 1 bears the most weight