MSK: Exam 1

What the definition of anatomy

• To cut up (via Greek & Latin)

• The science of the shape and structure of organisms and their parts

• Anatomy is the setting (structure) in which the events (functions) of life occur

What are the 3 types of anatomy

• Systemic

• Regional

• Clinical

Functions of the skeletal system

• Stability of limbs and thorax

• Protection for vital organs

• Attachment site for muscles and ligaments

• Blood cell production — continuous supply of new blood cells

• Mineral reservoir

What is the articular system

Joints: sites where movement occurs

Function of the muscular system

• Produce movement

• Maintain posture

• Production of heat

Function of the nervous system

• Regulate body activities

• Oversee coordination of all systems

• Sensory and motor functions

• Glandular secretions

Function of the circulatory system

• Distribute O2 and nutrients via cardiovascular (CV) system

• Carry CO2 and wastes from cells

• Regulate temperature

Function of lymphatic system

• Return protein and plasma from interstitial fluid to CV system

• Protects against disease

Definition of the sagittal plane; What does “mid-sagittal mean”

• Divides body into left and right sections

• Body divided into equal right and left halves - aka “median plane”

Definition of the frontal plane

Divides body into front (anterior) and back (posterior) sections - aka “coronal plane”

Definition of the transverse plane

• Divides body into upper and lower sections - aka “horizontal plane”

What does motion occur in (relate to plane & axis)

Motion occurs in a plane and about an axis

How does an axis pass through a plane

Perpendicularly

What movement is the mediolateral axis associated with

Flexion/Extension

What movement is the longitudinal axis associated with

Rotation

What movement is the anteroposterior axis associated with

Abduction/Adduction

Which plane is associated with the mediolateral axis

Sagittal

What movement is the longitudinal axis associated with

Transverse

What movement is the anteroposterior axis associated with

Frontal

What does parietal and visceral mean in directional terms

• Parietal: pertaining to forming outer wall of body cavity

• Visceral: pertaining to covering of organ in ventral cavity

Difference between flexion and extension; Which plane does this joint action occur in

• Flexion: decrease in angle

• Extension: increase in angle

• Sagittal

Difference between abduction and adduction; Which plane does this joint action occur in

• Abduction (ABD): moving away from midline of body - take away

• Adduction (ADD): moving towards midline of body - add

• Frontal

Difference between internal and external rotation; Which plane does this joint action occur in

• Internal Rotation: Anterior surface moves toward midline

• External surface: Anterior surface moves away from midline

What does circumduction mean

The combination of flexion/extension and abduction/adduction

What are the two main parts of the skeletal system and what makes up those parts

Axial:

• Head, neck, trunk (spine & sacrum)

Appendicular:

• Limbs

• Girdles (shoulder & pelvis)

What are the different classification of bone shapes

• Long

• Short

• Flat

• Irregular

• Sesamoid

Examples of long bone

• Femur

• Tibia

• Fibula

• Humerus

• Radius

• Ulna

What makes up the macrostructure of long bones (the regions)

• Epiphysis - proximal & distal parts

• Metaphysis

• Diaphysis - long shaft of bone

What makes up the macrostructure of long bones and where is it

• Periosteum: outer covering & highly innervated

• Endosteum: inside (surrounds medullary canal)

• Medullary Canal: most inner part

• Articular (hyaline) cartilage: at the ends of the bone

Example of short bones

Carpal bones

Example of flat bone

Parietal bone ( flat bones are typically in the skull)

Example of irregular bone

Vertebra

Example of sesamoid bone and what differentiates it

Patella - held in place by tendinous structures

What are the two types of bone on the structural level

• Cortical (compact)

• Trabecular (spongy)

Characteristics of cortical bone

• 80% of the skeleton

• Haversian Systems

• Slow turnover rates

Characteristics of trabecular bone

• Higher turnover rate

• Elastic

Structural Differences in Cortical vs. Trabecular Bone

Cortical

• Solid structure with few spaces

• Medullary Cavity

Trabecular

• Porous space

• Trabeculae

• Honeycomb

• Red Marrow

Functional Differences in Cortical vs. Trabecular Bone

Cortical

• Strength for weight-bearing/attachments

• Max strength is diaphysis

Trabecular

• Grows along lines of stress

• Lightweight scaffolding

Types of Bone - Tissue Level, and which is more mature

• Woven bone

• Lamellar — more mature

Types of Bone Cells and their Function

• Osteocytes

  • Ion exchange

  • Maintain bone tissue

  • Mechanosensory (respond to stresses)

• OsteoBLASTS

  • Bone FORMATION

  • Are stimulated by stress

• OsteoCLASTS

  • BREAKDOWN of bone

• Osteogenic cells

  • Undifferentiated cells in which osteoblasts are derived

What stimulates more production of osteoblasts

Stress

What is the best treatment for osteopenia and osteoporosis

Training/Lifting weights (more stress on bones)

Microstructures of compact bone

• Osteon: functional unit of compact bone

• Haversion Canal: contains blood vessels and nerves that serve cortical bone (aka central canal) - vertical

• Volkmann’s Canals: similar to haversion canals, BUT horizontal

• Lamella: concentric rings of tissue

• Lacuna: small cavity containing an osteocyte

• Canaliculi: microscopic canals between adjacent lacunae

Microstructures of Trabecular Bone

• Spicules (mineralized tissue)

  • Basic unit of structure

    • Trabecular - reference name in bone

      • Lattice work for marrow spaces

      • Scaffolding for maximum support in places of high stress

    • Contain osteocytes

• Red Marrow: RBC/WBC/platelet production

  • Often found in flat bones and end of long bones

Yellow Bone Marrow Characteristics

• Typically inside the medullary canal of long bones

• High fat content

• WBC production

Characteristics of the Nutrient Artery System

• Nutrient Artery: Branches from major arteries and enters through periosteum

  • Poor arterial supply → poor bone growth/healing

• Nutrient Foramina: path through the diaphysis to medullary cavity

  • Supplies bone marrow, cancellous bone, and deep compact tissue

Function of the metaphyseal-epiphyseal system

• Arteries supplying the joints

• Supplies the end of long bones

Where is the nerve supply in bones

Periosteum — very rich with sensory nerve endings

Characteristics of Intramembranous Ossification

• Occurs as fetus

• Undifferentiated mesenchymal cells differentiate into osteoblasts

• Deposit organic matrix

• Occurs in flat bones

Characteristics of Endochondral Ossification

• As fetus, cartilage make mold of bone

• Osteoblasts build around center of diaphysis in utero

• Bone replaces cartilage from birth to adult

• Primary & secondary ossification centers

• Bone healing after fracture

Two types of bone growth and development

• Intramembranous

• Endochondral

How does length and diameter increase during Endochondral Ossification and what are bone growth factors controlled by

• Length: grow from center toward the end

• Diameter: bone is added to outside, osteoclasts remodel from inside

Bone growth controlled by hormones

Where do the centers form in primary vs secondary ossification

Primary: diaphysis

Secondary: epiphysis

When the epiphyseal plates are closed, what does that mean

The bones are fully grown

How does the bone maintain and repair itself

• Constant remodeling of bone through osteoclast and osteoblast activity (10%/yr)

  • Maintains normal bone mass

  • Repair of daily wear and tear

• Wolff’s Law

  • SAID principle

    • Specific Adaptation to Imposed Demands

      • Tissue remodels along the lines of greatest stress

Mechanisms of remodeling bone

• Activation

  • Osteocytes

• Resorption

  • Osteoclasts

• Formation

  • Osteoblasts

Characteristics of the skeletal system during aging

• 90% peak bone density: F=18yrs, M=20yrs

• Peak bone density ~ 30yrs

• >30yrs: Resorption > Formation

  • Can offset with exercise

• Menopause: significant increase in resorption due to hormonal changes

  • Low estrogen levels

  • Also happens in younger women with amenorrhea or oligomenorrhea

Osteopenia vs. Osteoporosis

• Osteopenia: bone mineral density 1.0-2.5 SD below normal healthy 30yr

• Osteoporosis: bone mineral density >2.5 SD below normal healthy 30yr

Mechanism of Stress Fracture

• Osteoclast activity > Osteoblast activity

  • rate of increase in the volume of stresses

  • rate of increase in the intensity of stresses

What are Salter-harris Fractures and describe the different levels

Fractures through open epiphyseal plates (often in younger athletes)

• Type 1: Through growth plate

• Type 2: Through growth plate and metaphysis (most common)

• Type 3: Through growth plate and epiphysis

• Type 4: Through all 3 elements

• Type 5: Crush injury of growth plate (compression fracture)

Major Regions of the Skull

• Frontal

• Parietal

• Occipital

• Temporal

• Mandible

• Maxilla

• Nasal

• Zygomatic

• Sphenoid

The Spine (Vertebrae): # and type of vertebrae

• 7 - Cervical

• 12 - Thoracic

• 5 - Lumbar

• 5 - Sacral

• 4 - Coccygeal

Which vertebrae is the biggest and has the largest body

Lumbar vertebrae

How many ribs are there

24

Which ribs are true, false, and floating

True: 1-7

False: 8-10

Floating: 11-12

Which vertebrae are the ribs attached to

Thoracic

What attaches the ribs to the sternum

Cartilage

What make up the shoulder complex

• Clavicle

• Scapula

• Glenoid

Bones that make up the arm

• Humerus

• Ulna

• Radius

Radius vs. Ulna

Radius:

• thumb side

• Moves during pronation

Ulna:

• pinky side

• Doesn’t move during pronation

Names and order of carpal bones

Some Lovers Try Positions That They Can’t Handle

• Scaphid

• Lunate

• Triquetrum

• Pisiform

• Trapesium

• Trapezoid

• Capitate

• Hamate

How many metacarpals, phalanges, and phalanx

• Metacarpals: 5 (numbered I to V)

• Phalanges: 5

• Phalanx: 14

  • 2 in digit I (thumb) — proximal and distal

  • 3 in digits 11 to V — proximal, middle, and distal

Parts of the pelvis what do they form when put together

• Illium

• Ischium

• Pubis

Acetabulum

Bones in the leg

• Femur

• Tibia: big toe side

• Fibula: pinky side

Name and order of the tarsals

• Talus

• Calcaneus

• Navicular

• Cuboid

• Cuneiforms

  • Lateral

  • Intermediate

  • Medial

How many metatarsals, phalanges, and phalanx

• Metatarsals: 5

• Phalanges: 5

• Phalanx: 14

  • 2 on 1st phalange (big toe) — proximal and distal

  • 3 on 2-5 Phalanges — proximal, middle, and distal

What does arthrology mean and what is a joint

• The study of joints

• Where two or more bones articulate with one another

What is the function of joints

• Allow efficient movement patterns

• Provide stability to the bony skeleton

What is the Structural Classification of Joints

• Synovial

• Fibrous

• Cartilaginous

What is the Functional Classification of Joints

1. Synarthrosis

2. Amphiarthrosis

   1. Syndesmosis

   2. Synchondrosis

   3. Symphysis

3. Diarthrosis

   1. Hinge

   2. Pivot

   3. Condyloid

   4. Ellipsoid

   5. Saddle

   6. Ball and Socket

   7. Plane (gliding)

What are the two types of synarthroidal joints

• Sutures

• Gomphoses

Characteristics sutures (joint def.)

• Immovable fibrous joints

• Fibrous periosteum forms between bones

• Joints of the skull

Characteristics of gomphoses

• Attachment of a tooth in its socket

• Tooth held in place by fibrous periodontal ligament

• Allows tooth to move slightly while chewing

What are two types of amphiarthroidal joints

• Ligamentous

• Cartilaginous

Characteristics of ligamentous joints

• Slightly moveable

• Syndesmosis (fibrous joint where two adjacent bones are strongly united by ligaments or a broad sheet of connective tissue)

• Ligamentous interosseous membrane provides stablility

Characteristics of cartilaginous joints

• Slightly moveable

• Bones separated by fibrocartilaginous disk

• Joints reinforced by ligaments

• Intervertebral discs

• Pubic symphysis

Characteristics of Diarthroidal joints

• Synovial joints (has synovial fluid to lubricate joint)

• Very mobile

• Ligamentous joint capsule

• Synovial membrane

• Synovial fluid

• Articular cartilage

  • Need all points in blue to be considered a true diarthroidal joint

Characteristics of gliding joints and examples

• aka “plane” joint

• Nonaxial

  • can move superior/inferior, anterior/posterior, or rotate

• Examples:

  • Acromioclavicular joint

  • Intercarpal and intertarsal joints

Characteristics of hinge joints and examples

• aka “ginglymus”

• Uniaxial

  • Motions of flexion and extension are allowed (just sagittal)

Example:

• Ulnohumeral joint

Characteristics of pivot joints and examples

• aka “trochoid”

• Uniaxial

  • only rotation

Example:

• Atlandtoaxial joint (between C1 & C2 vertebrae)

Characteristics of ellipsoid joints and examples

• biaxial

  • flexion/extension

  • abduction/adduction

  • circumduction

  • rotation not possible

• convex:concave surfaces

  • ex: glenoid (convex) & humerus (concave)

Example:

• Radiocarpal joint

Characteristics of condyloid joints and examples

• Biaxial

  • Flexion/extension

  • Rotation

• Convex:concave surfaces

Example:

• Metacarpophalangeal joint

• Tibiofemoral joint

Characteristics of saddle joints and examples

• Biaxial

  • flexion/extension

  • abduction/adduction

  • rotation

  • circumduction

• Both bones have saddle shapes

  • saddles fit together

Example:

• Carpometacarpal joint of thumb

Characteristics of ball and socket joints and examples

• Triaxial

  • flextion/extension

  • abduction/adduction

  • rotation

  • circumduction

Example:

• Hip

• Glenohumeral

What do ligaments do

Connect bone to bone

Two functions of ligaments

• Mechanical function

  • hold adjacent bones together

• Sensory function

  • provide feedback to nervous system regarding joint motion and joint position (proprioception)

What is the difference between an extrinsic and intrinsic ligament

• Extrinsic:

  • outside joint capsule

• Intrinsic:

  • inside joint capsule

What is the ligament structure

• Primary cells are fibroblasts

• Most prevalent fibrous component is collagen

  • Type I is most prevalent

  • Proteoglycans also present

  • Similar to structure to tendon, but more elastic

• 2/3 of extracellular matrix is water

• Bundles of collagen fibers comprise ligaments

  • Bundles can be arranged:

    • In parallel

    • Obliquely

    • Spiral arrangement

• Arrangement of fibers is dictated by ligament function

What is collagen and the characteristics of the 3 types

The primary structural protein of the body — different types depend on structure and function

Type I

• Dense fibrils

• High tensile strength

• ex: tendon & ligaments

Type II

• >50% dry wt of hyaline cartilage

• Less dense fibrils

• ex: articular cartilage and nucleus of disc

Type III

• Immature collagen

• least tensile strength

• associated with Type I

• ex: vessels, skin

What is the structure of ligament attachment to bone

4 Zones: (gets more stiff when closer to bone)

• Ligament (collagen)

• Fibrocartilage

• Calcified fibrocartilage

• Cortical bone

Sharpey’s Fibers

• Ligamentous fibers which penetrate fibrocartilage

• Some ligamentous fibers also blend with periosteum