Lab Practical 2: Axial Skeleton

Head

Bony expansion carried on a narrow neck

Nasal Bone

Bridge of nose

Meatus

Canal-like passageway

Short bones

Carpals and tarsals

Zygomatic Bone

Cheek bones

Orbicularis Oris

Closes Lips (kissing muscle)

Orbicularis Oculi

Closes eyes

Temporalis

Closes jaw

Inguinal Ligament

Connective Tissue which runs from the anterior superior iliac spine to the inguinal canal

Linea alba

Connective tissue band from the xiphoid to pubic bone

Diaphragm

Contracts on inspiration, relaxes on expiration

Flat Bones

Cranial bones (scapular, sternum, and ribs)

Combination

Flexor hallucis longus (action, location, and length)

Function

Flexor, extensor

Location

Frontalis, temporalis

Groove

Furrow

Decalcified Bone

Has organic matter, removed calcium ions

Long bones

Have a longitudinal axis (leg bones, or bones of fingers)

What kind of cartilage is found in the larynx?

Hyaline Cartilage

What kind of cartilage is at the ends of long bones?

Hyaline cartilage

What kind of cartilage is between the ribs and sternum?

Hyaline cartilage

What kind of cartilage is found between the pubic bones?

Hyaline cartilage

Notch

Indentation at the edge of a structure

Spongy Bone

- Also called cancellous or trabecular bone - It is found in the long bones and it is surrounded by compact bone

Compact bone

- Also called cortical bone - Surrounds spongy bone - Heave, tough, and compact in nature

Intervertebral Discs

- Annulus fibrosus (outside ring - hyaline cartilage) - Nucleus Pulposus (inside circle)

Atlas C1

- Anterior tubercle - Posterior tubercle - Transverse foramen for vertebral arteries to pass through - Superior articular facet, articulates with condyles of skull - Allows flexion and extension of head and neck

Number of Origins

- Biceps = 2 - Triceps = 3 - Quadriceps = 4

External Intercostals

- Contract on inspiration - Relax on expiration - Origin is rib above, insertion is rib below - Fibers run downward and medially - Located laterally and more superficially then the internal intercostals

Internal Intercostals

- Contract with forced expiration - Origin is the rib below, insertion is the rib above - Fiber run upward and medially - Located medially and deep to external intercostals

Axis C2

- Dens (odontoid process) - Allows rotation of head and neck

Parts of a Long Bone

- Diaphysis - Epiphysis - Epiphyseal line or plate - Spongy bone - Compact bone - Medullary cavity - Articular cartilage - Periosteum (Contains blood vessels and nerves)

Temporal Bone

- External auditory meatus - Internal auditory meatus - Mastoid process - Zygomatic process - Styloid process - Mandibular fossa-TMJ Joint - Stylomastoid Foramen - Jugular Foramen - Carotid Canal

Vertebrochondral

- False ribs - Indirectly attached to sternum (8,10)

Skeletal Muscle Organ

- Fibers - Nuclei - Endomysium - perimysium - epimysium

Sternocleidomastoid

- Flexes the head - Unilateral contraction rotates the head toward the opposite shoulder

Vertebral

- Floating ribs - No sternal attachment (11,12)

Paranasal Sinuses

- Frontal - Ethmoid - Sphenoid - Maxillary

Epicranius Muscles

- Frontalis muscle - aponeurotic - Occipitalis muscle

Sphenoid Bone

- Greater wings - Lesser wings - Pterygoid processes - Sella turcica - Sphenoid sinus - Optic foramen (passageway for optic nerve) - Foramen Rotunda (passageway for Trigeminal nerve) - Foramen Ovale (passageway for trigeminal nerve)

Blood Supply to Compact Bone

- Haversion canal - Volkman's canal

Ethmoid Bone

- Horizontal plate (cribriform plate) - Perpendicular plate - Lateral masses (superior and inferior concha) - Crista Galli where dura mater attaches

Thoracic Vertebrae (T1-T12)

- Identify articular surface for the ribs (transverse coastal facet) - Generally downward pointing spinous processes

Tendinous Inscriptions

- In rectus abdominus - makes abs

Infrahyoids

- Inferior to hyoid bone - Depresses hyoid bone

Erector Spinal Complex

- Intercostalis - Longissimus - Spinalis - Extension of spine

Bone Shapes

- Long - Short - Flat - Irregular - Sesamoid - Wormian

Sternum

- Manubrium - body - xiphoid process - Jugular notch - sternal angle - xiphisternal joint

Muscles for chewing

- Masseter - Temporalis - Pterygoids

Mandible

- Mentum (mandibular symphysis) - Body - Ramus - Angle - Inferior Alveolar margin - Mandibular foramen (tooth sensation nerve) - Mental foramen (blood vessels and nerves) - Condyloid process - Coronoid process

Occipital Bone

- Occipital crest/protuberance - Nuchal lines - Formen magnum - Occipital Condyles - Hypoglossal canal (Passage for hypoglossal cranial nerve)

What movements are possible for the mandible?

- Opening - closing - rightward jaw translation - leftward jaw translation - protrusion - retrusion

External/Internal Obliques, Transverse Abdominus

- Origin is the ribs, vertebrae, ilium, dorsolumbar fascia - Insertion is the line alba - Aponeurosis binds the muscles together

Microscopic Structure of Compact Bone

- Osteon (Haversion system) - Haversion canal or central canal - Concentric lamellae of matrix and osteocytes - Lacuna - Canaliculae - Interstitial/intermediate lamellae

Sutures

- Saggital - Lambdoidal - Squamosal - Coronal

Curvatures

- Scoliosis - kyphosis - Lordosis

Rib Structure

- Shaft - Head - neck - Tubercle

Sacrum (5 fused vertebrae)

- Smooth anterior surface - Rough posterior surface - Median crest (formed by spinous processes) - Posterior foramen - Ala - Sacral canal - Sacral hiatus

Identify the following parts of Lumbar Vertebrae

- Spinous process = can feel when palpating (posterior) - Transverse processes = in cervical vertebrae, for vertebral arteries to pass through - Vertebral foramen = spinal cord passes through - Body = thick anterior portion - Neural Arch - Pedicles = body meets transverse process - Lamina = transverse process meets pious process - Superior and inferior articular processes - Intervertebral foramen = spinal nerves go through

Suprahyoids

- Superior to hyoid bone - Elevates the hyoid bone

Frontal Bone

- Supraorbital foramen - Glabella

Lumbar Vertebrae (L1-L5)

- Thick and heavy body - "hatchet-like" spinous process

Rectus Abdominus

- This muscle is a trunk flexor - Origin is pubic bone, insertion is xiphoid process

Vertebrosternal

- True ribs - Directly attached to sternum (1,7)

Maxillary (Maxilla)

- Upper jaw; two fused bones - palatine process - infraorbital foramen - alveolar margin - Incisive fossa (whole in palatine process - inferior view)

Cross section through muscle organ

- endomysium - Perimysium - Epimysium - Sarcolemma - Neuromuscular junciton - Thick filament - Think filament - sarcomere - T tubule - sarcoplasmic reticulum - terminal cisternae - Longitudinal tubule

Platysma

- superficial muscle of anterior neck - Scared muscle

What three parts of vertebrae does rib articulate with?

- transverse costal facet - Superior costal facet - Pedicle

Calcified Bone

hardened by the deposits of salts

Inferior Nasal Concha

located on each side of the nasal septum, attached to the lateral wall of the nasal cavity

Vomer

nasal septum

Tuberosity

Large round projection, may be roughened

Trapezius

Located on posterior neck

What is the insertion of the chewing muscles

Mandible

Jugular Formen

Passage for Glossopharyngeal, Vagus, and Spinal accessory nerves

Stylomastoid Foramen

Passage for facial cranial nerve

Carotid Canal

Passage for internal carotid artery

Sesamoid bones

Patella, sesamoid bones are formed with tendons

Crest

Narrow ridge of bone usually prominent

Line

Narrow ridge of bone; less prominent than a crest

Fissure

Narrow, slitlike opening

What passes through openings in the cribriform plate?

Olfactory Nerve (smell)

Levator labii superioris

Opens lips

What is normally found in lacunae?

Osteocytes (mature bone cells)

Extensors

Posterior deep muscles (post vertebral)

Palatine Bone

Posterior hard palate

What is the action of the occipitals muscle?

Pulls scalp posteriorly

Epicondyle

Raised area on or above a condyle

What is the action of the frontalis?

Raises eyebrows

Direction of muscle fibers

Rectus abdominus (Rectus = straight)

Shape

Rhomboids, triangulareis, Trapezius

Foramen

Round or oval opening through the bone

Condyle

Rounded arctic alar projection, often articulates with a corresponding fossa

External Obliques

Run downward and medially

Internal Obliques

Run upward and medially

What would normal be found in the central canal?

Runs parallel to the long axis of the bone and carries blood vessels, nerves, and lymphatic vessels through the bony matrix

Bone Markings

Serve as attachments points for tendons, ligaments, muscles, and openings for blood vessels or nerve passages

Fossa

Shallow basin like depression in a bone, often serving as an articular surface

Spine

Sharp, slender, often pointed projection

Wormian (Sutural) bones

Small bones between cranial bones (wormian bones of lambdoid suture)

Tubercle

Small rounded projection or process

Zygomaticus

Smiling muscle (Major and minor portion)

Facet

Smooth, nearly flat articular surface

What bone would be the origin of the pterygoids?

Sphenoid

Characteristics of Skeletal muscle cells

Striations (stripes) Multinucleate (more than one nucleus) Long, cylindrical shape

What join do the chewing muscles act over?

TMJ Joint

Coccyx (3-5 fused vertebrae)

Tailbone

What is the galea aponeurotic?

Tough fibrous sheet of connective tissue that extends over the cranium, forming the middle, third layer of the scalp

How to identify Cervical Vertebrae

Transverse foramen and prominent and sometimes split spinous processes

Mentalis

Wrinkles chin, protrudes lower lip

Flexors

Anterior deep muscles (pre vertebral)

Process

Any bony prominence

Ramus

Armlike bar of bone

Sinus

Bone cavity filled with Arie and lined with a mucus membrane

Organ

Doesn't move

Depressor labii inferioris

Draw lower lip inferiorly

Depressor angle oris

Draws corners of mouth downward and laterally (frowning muscle)

Transvers Abdominus

Fibers run transversely

What kind of cartilage is found between vertebrae?

Fibrocartilage

What are interstitial lamellae?

Fill the spaces between osteons

Relative size or length

Maximus, minimus, brevis, and longus

Insertion

Moves

Bones

The organs of the skeletal system (axial bones) - Bones of the skull - Ribs - Vertebrae

Irregular Bones

Vertebrae and facial bones

Trochanter

Very large, blunt, irregularly shaped process (the only examples are on the femur)