A&P - Lab Practical Unit 2

6 Classifications of Bones

1. Long

2. Short

3. Flat

4. Irregular

5. Sesamoid

6. Sutural (Wormian)

Epiphysis

The end region of a long bone

Diaphysis (shaft)

The shaft/main region of a long bone

Metaphysis

The region of a long bone between the epiphysis and diaphysis

Medullary cavity

The central cavity of a long bone, containing bone marrow

Cortex (cortical bone)

The dense outer region of bone, i.e. compact bone

Endosteum

The membrane lining the medullary cavity of bone

Periosteum

The membrane covering the outer surface of bone

Red bone marrow

Found in the epiphysis/spongy bone; site of blood cell formation

Yellow bone marrow

Found in the medullary cavity; functions mainly as fat/energy storage

Fossa (fossae)

A shallow depression on a bone

example: olecranon fossa of the humerus

Foramen (foramina)

An opening in a bone, usually a passageway for nerves or vessels

example: foramen magnum of the skull

Meatus, canal

A tunnel through bone

example: external auditory meatus of the temporal bone

Sinus, antrum

An enclosed cavity in a bone

example: frontal sinus

Processes (bone markings)

Projections extending from a bone's surface

Condyle

A rounded process, usually found near articulations

example: femoral condyle

Epicondyle

A projection above a condyle

example: epicondyle of humerus

Head (bone marking)

A rounded process at the end of a bone

example: head of femur

Crest (bone marking)

A narrow ridge

example: iliac crest

Spine (bone marking)

A slender, pointed process

example: scapular spine

Trochanter, tuberosity, tubercle

Variously-shaped bumps/processes near articulations or muscle attachments; example: greater trochanter of femur

Trabeculae

The structural struts/plates of spongy (cancellous) bone

Haversian (central) canal

The central canal of an osteon that allows passage of blood vessels

Perforating (Volkmann's) canals

Canals that run perpendicular to the central canal, connecting blood vessels between osteons

Sutures (skull)

Immovable joints connecting the bones of the skull

types include: coronal, sagittal, lambdoid, and squamous

Coronal suture

The suture between the frontal bone and the two parietal bones

Sagittal suture

The suture between the two parietal bones

Lambdoid suture

The suture between the parietal bones and the occipital bone

Squamous suture (skull)

The suture between the temporal bone and the parietal bone

Wormian (sutural) bones

Extra, irregular isolated bone pieces that occur within a suture of the cranium in addition to the usual centers of ossification

Frontal Bone features

Supraorbital margin, supraorbital notch or foramen, and frontal sinus

Parietal Bones

2 bones forming the sides and roof of the cranium

Temporal Bones — features

Mandibular fossa, external auditory meatus, internal auditory meatus, zygomatic process, styloid process, mastoid process, carotid canal

Sphenoid Bone — features

Greater and lesser wings, sella turcica, hypophyseal fossa, optic canals (foramina), foramen ovale

Occipital Bone — features

External occipital protuberance, foramen magnum, occipital condyles, jugular foramen, hypoglossal canal

8 Cranium (braincase) bones

Frontal

2 Parietal

2 Temporal

Sphenoid

Occipital

Ethmoid

Maxilla — features

Palatine process (hard palate), zygomatic process, maxillary process, alveolar process, infraorbital foramen

Mandible — features

Body, ramus, angle, mandibular condyle (condylar process), coronoid process, alveolar process, mandibular foramen, mental foramen

Facial bones (named, unpaired/other)

Maxilla, Mandible, Palatine bones, Zygomatic bones, Lacrimal bones, Nasal bones, Vomer; also forms the Nasal septum

22 Facial bones

The bones of the face, as distinguished from the 8 cranium/braincase bones

Vertebral Column composition

26 bones total in an adult; 24 individual vertebrae grouped into cervical, thoracic, lumbar, and sacral types, plus the sacrum and coccyx (fused caudal vertebrae)

Sacrum and coccyx

The caudal end of the vertebral column; consist of variable numbers of vertebrae that fuse together during development

3 main types of vertebrae

Cervical, Thoracic, and Lumbar

General vertebra features

Body (centrum), transverse process (lateral spine), spinous process (dorsal spine), vertebral canal (spinal canal), intervertebral foramen, intervertebral disc

Cervical vertebrae (7) — unique features

Transverse foramina, bifid spinous process, superior articular facets, inferior articular facets

C1 (Atlas)

The first cervical vertebra; articulates with the skull

C2 (Axis)

The second cervical vertebra; has the odontoid process (dens)

Thoracic vertebrae (12) — unique feature

Rib facets: transverse costal facets on the transverse processes, and demifacets on the vertebral bodies

Lumbar vertebrae (5) — unique feature

Lack transverse foramina and rib facets

Sacrum (5 fused) — features

Base, apex, sacral canal, sacral foramina, transverse lines, sacral curve, sacral hiatus, sacral cornu, sacral promontory

Coccyx

Several fused vertebrae forming the tailbone, at the caudal end of the vertebral column

Thorax (rib cage) — function

Protects the organs of the chest cavity; provides attachment for muscles involved in respiration and upper limb movements; includes the sternum and ribs

Sternum — features

Manubrium, body, xiphoid process, jugular (suprasternal) notch, costal notches

Ribs — classification

12 pairs total

7 pairs of true ribs

• have costal cartilages connecting them to the sternum)

5 pairs of false ribs

• first 3 pairs, vertebrochondral ribs, merge with cartilage of the 7th rib

• last 2 pairs are floating ribs that attach to thoracic vertebrae and do not connect to the sternum

Rib — features

Head, neck, tubercle, body, sternal end, costal cartilage

Pelvic Girdle (os coxa)

Formed by fusion of the ilium, ischium, and pubis into a single hip bone

Ilium — features

Acetabulum, iliac crest, greater sciatic notch, iliac spines (anterior superior & inferior; posterior superior & inferior)

Ischium — features

Ischial tuberosity, ischial spine, lesser sciatic notch, obturator foramen

Pubis — feature

Pubic symphysis

Femur — features

Head, neck, shaft, greater trochanter, lesser trochanter, linea aspera, medial and lateral condyles, intercondylar notch or fossa

Tibia — features

Head (medial and lateral condyles), tibial tuberosity, anterior crest or margin, medial malleolus

Fibula — features

Head, lateral malleolus

Tarsals

Calcaneus, talus, navicular, cuboid, and the cuneiforms (medial, intermediate, and lateral)

Foot bones (besides tarsals)

Metatarsals and Phalanges

Knee Joint — bones

Distal end of femur, proximal end of tibia, proximal end of fibula, and the patella

Knee Joint — tendons/ligaments

Quadriceps tendon, patellar ligament, tibial collateral ligament, fibular collateral ligament, anterior cruciate ligament, posterior cruciate ligament, and the medial & lateral menisci

Pectoral Girdle

The articulation of the upper arm and the trunk; includes the scapula and the clavicle

Scapula — features

Glenoid fossa (cavity), scapular spine, inferior angle, acromion process, coracoid process, vertebral (medial) border, axillary (lateral) border, supraspinous fossa, infraspinous fossa

Clavicle — features

Acromial end and sternal end

Shoulder Joint — bones

Scapula, clavicle, and head of humerus

Shoulder Joint — ligaments

Acromioclavicular, coracoclavicular, glenohumeral, coracohumeral, coracoacromial

Humerus — features

Head, greater tubercle, lesser tubercle, intertubercular (bicipital) groove, deltoid tuberosity, capitulum (lateral condyle), trochlea (medial condyle), olecranon fossa, coronoid fossa, medial and lateral epicondyles

Radius — features

Head, neck, radial tuberosity, styloid process, ulnar notch

Ulna — features

Semilunar (trochlear) notch, olecranon process, coronoid process, radial notch, styloid process

Carpals — Distal Row

Trapezium, Trapezoid, Capitate, Hamate

Carpals — Proximal Row

Navicular (scaphoid), Lunate, Triquetrum, Pisiform

Hand bones (besides carpals)

Metacarpals and Phalanges