Bones – Test Review
5 functions of bones:
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•
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•
Protection – examples: skull, ribs
Support – for internal organs
Storage – of minerals (esp. Ca, P)
Movement – by muscles pulling on bones
Hematopoiesis – blood cell formation (RBC)
2 subdivisions of the skeletal system
• Axial skeleton – skull, thorax, vertebrae
• Appendicular skeleton – limbs, girdles
4 Classifications of bones
• Long
– Ex. Upper and lower
limbs
• Short
– Ex. Carpals and tarsals
• Flat
– Ex. Ribs, sternum, skull,
scapulae
• Irregular
– Ex. Vertebrae, facial
Parts of a Long Bone
• Epiphysis – ends of long
bones
• Diaphysis – shaft part
of bone for length
• Periosteum – wraps
around diaphysis
• Sharpey’s fibers – used
to secure periosteum to
diaphysis
Spongy vs. Compact Bone
• Spongy bone – found
on epiphysis
 Small needle-like
pieces of bone
 Many open spaces
• Compact bone - Dense
and smooth
Microanatomy of Bone
• Osteons (Haversian
system)
• Central (Haversian)
Canals
• Lamellae – Rings
around the central
canal
• Canaliculi – Tiny canals
• Lacunae - Cavities
containing bone cells
Bone Formation, Growth, Remodeling
Bone Formation
 In embryos, the skeleton is
primarily hyaline cartilage
 During development, much of
this cartilage is replaced by bone
 Cartilage remains in isolated
areas
 Bridge of the nose
 Parts of ribs
 Joints
Bone Growth and Remodeling
Cartilage is broken down, bone
replaces cartilage, epiphyseal
plates allow for growth of long
bones during childhood
 Bones are remodeled and
lengthened until growth
stops
 Bones change shape
somewhat
 Bones grow in width
PTH / Calcitonin
Bone Cells
• Osteocytes – mature bone cells
• Osteoclasts – breakdown bone
• Osteoblasts – build bone
• Hyaline cartilage is most abundant cartilage
Bones of the Cranium (skull)
Cranium bones
• Frontal bone
• Temporal bone
• Occipital bone
• Parietal bone
Diagram
Bones of the skull – facial bones
Facial bones
• Zygomatic
• Nasal
• Maxilla
• Lacrimal
• Sphenoid
• Mandible
Diagram
Bone Markings (skull)
• Foramen magnum – on occipital bone
• Styloid process – temporal bone
• Mastoid process – temporal bone
• Zygomatic process – temporal bone
Sutures of the skull
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•
•
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Sagittal suture
Coronal suture
Squamous suture
Lambdoid suture
Fractures
• Treatment is reduction
open or closed
• Types of fractures:
• Simple
• Compound
• Comminuted
• Impacted
• Epiphyseal
• Greenstick
• Osteomyelitis (problem)
Fracture Healing Process
• Healing
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–
–
–
Hematoma
Fibrocartilaginous callus
Bony calllus
Remodeling by
osteoclasts/osteoblasts
Pectoral Girdle (bones, joints)
• Clavicle, Scapula make up the girdle
• Joints: S/C (sternoclavicular)
A/C (acromioclavicluar) - separation
Glenohumeral joint - dislocation
• Glenoid of the scapula
• Coracoid process
Bone of the Arm
• Humerus
Head of the humerus (proximal) articulates
with the glenoid of the scapula
Distal: condyle, trochlea, capitulum to help
form the elbow joint
• Fossa – Ant. Coronoid fossa
Post. Olecranon fossa
• Deltoid tuberosity – for the deltoid muscle
Bones of the Forearm
• Radius
• Ulna
Humerus
• Anatomical Neck – site
of fractures
Interosseous membrane
• Surgical neck
Carpals, Metacarpals, Phalanges
• Carpals – 8 bones of the
wrist
• Metacarpals – 5 bones
of the hand (knuckles)
• Phalanges – 14 bones of
the fingers
Pelvic Girdle
• Bones – fusion of ilium,
ischium, and pubis
• Together they make the
coxal (hip) bone
• They all meet together
at the acetabulum
• Locate the pubic
symphysis and the
obturator foramen
Bones of the Thigh and Leg
• Thigh – head of the
femur articulates with
the acetabulum
superiorly and inferiorly
at the knee with the
tibia/fibula
• Longest, strongest bone
in the body
• Bones of the leg Tibia/fibula
• Tibia bears the weight
of the leg; fibula is nonweight bearing
• Distal end of tibia is
medial malleolus and
lateral malleolus is the
distal end of the fibula
Arches of the Foot