skeletal system patho

how many bones does adult have

206bones adult

Appendicular - 126 bones

Axial - bonww

Function of skeletal system

Body support protection movement and blood cell production

Compact bone

The outer portion of bone is composed of ___

cancellous bone

The inner portion, termed the medullary canal, is

made up of ____

trabecullar pattern

This intricate, web-like bony structure is visible on a

properly exposed radiograph of the skeletal system

and is often referred to as the ___

Diploë

Specific to the cancellous bone located within the Skull

Diaphysis

shaft portion, primary site of ossification

Epiphysis

expanded end portion, secondary site of ossification

Methaphysis

▪ growth zone between the diaphysis and epiphysis; area

of greatest metabolic activity in bone

Osteoblasts

• These are bone-forming cells that line the medullary

canal and are interspersed throughout the periosteum.

• They are responsible for bone growth and thickening,

ossification, and regeneration.

Osteoclasts

Specialized cells that break down bone to enlarge the

medullary canal and allow for bone growth

Osteogenesis imperfecta

“brittle-bone” disease

▪ Autosomal dominant

▪ Deficient and imperfect formation of bone

tissue, skin, sclera, inner ear, and teeth

▪ Radiographic evaluation will demonstrate

multiple fractures in various stages of

healing and a general decrease in bone

mass

Osteogenesis imperfecta congenita

present at birth.

▪ Infants with this disease usually have multiple

fractures at birth that heal only to give way to new

fractures.

▪ This results in limb deformities and dwarfism and

may lead to death

osteogenesis imperfecta tarda

Fractures might not appear

for some years after birth

and then generally stop

once adulthood is reached

Achondroplasia

Most common inherited disorder

affecting the skeletal system.

▪ Autosomal dominant.

▪ Disturbance in endochondral

bone formation results in the

inability of cartilage in the

epiphysis to normally convert to

bone, impairing the longitudinal

growth of the bone

Osteopetrosis

“Marble bone” disease

▪ Increase in bone density and defective bone contour.

▪ All bones are affected

▪ Radiographs demonstrate an increase in density and

thickness of the cortex, an increase in the number

and size of trabeculae, and a decrease in marrow

space

Albers-schonberg disease

▪ fairly common form of osteosclerotic

osteopetrosis.

▪ This autosomal dominant, delayed, benign

skeletal anomaly involves increased bone density in conjunction with fairly normal bone contour.

Syndactyly

- Failure of fingers or

toes to separate

- physical appearance

of webbed digits

Polydactyly

Presence of extra digits

Club foot (Talipes)

▪ Inward turning of the foot at the ankle

▪ prevents normal weight bearing.

▪ common in males

▪ may occur bilaterally

▪ Generally corrected by casting or

splinting the foot in the correct

anatomic position

Developmental Dysplasia of the Hip (DDH)

Due to acetabular malformation, causing the head

of the femur to be displaced superiorly and

posteriorly.

▪ DDH may be unilateral or bilateral

▪ More common in females

▪ Radiographic measurements of the AP pelvis are

obtained

Spina bifida

Incomplete closure of the vertebral canal,

commonly in the lumbosacral area

Craniosynostosis

Premature or early closure of any

cranial suture, leading to

overgrowth in the unfused suture

to accommodate brain growth.

▪ Although this defect may be

corrected with surgery, brain

damage may occur

Anencephaly

Non-formation of the brain and cranial

vault

▪ Usually, only facial bones are formed

▪ This abnormality results in death shortly

after birth and may be diagnosed before

birth by ultrasonography.

▪ Anencephaly is a neural tube defect,

and its cause is unknown

Osteomyelitis

Infection of bone and bone marrow caused by a

pathogenic micro-organism

▪ Infection may be via hematogenous route, from

contiguous site, injection, or direct introduction

▪ Imaging Modality: Radiography is not as

sensitive as nuclear scans or MRI in detection

Tuberculosis

▪ Chronic inflammatory disease

caused by Mycobacterium tuberculosis

▪ Hip, knee, and spine (Potts disease)

are most commonly affected

▪ “worm-eaten” appearance in

radiograph

Pott disease

Tuberculosis of the spine

▪ It destroys the spine, causing

softening and eventual collapse

of the vertebrae, which results

in paravertebral abscess

formation and exerts abnormal

pressure on the spinal cord

Arthropathies

Infectious arthritis

▪ Pathogenic micro-organisms

Rheumatoid arthritis

▪ Autoimmune disease

Ankylosing spondylitis (Marie-Strumpell disease)

▪ Progressive, usually involves the spin

Osteoarthritis

Most common type, also known as

Degenerative joint disease

Gouty arthritis

▪ Inherited metabolic disease

▪ Tophi

▪ “Rat bite” erosio

Reiter syndrome

is a variant of rheumatoid arthritis occurring most

commonly in young males

.

▪ It has been associated with bacterial infections of the

GIT and genitourinary systems.

▪ The sacroiliac joints, heels (calcanei), and toes are

generally affected in this syndrome, sometimes

referred to as “lover’s heel.”

▪ Although the radiographic appearance may mimic RA,

Reiter syndrome affects the feet instead of the hands

Paget’s disease (osteitis deformans)

▪ Metabolic disorder of unknown cause.

Cotton wool appearce

▪ Researches indicate a genetic link and the possible

role of viral infectious agents.

▪ Fairly common in the older adult population.

▪ Affecting men twice as frequently

▪ Usually begins in the fifth decade of life

▪ May affect one or more bones (Pelvis, spine, and skull

– MOST common

Two stages of pagets disease

Osteolytic Stage

▪ Bone undergoes continuous destruction

Osteoblastic Stage

▪ Bone is simultaneously replaced by abnormally

soft and poorly mineralized materia

Compression fracture

Most frequent

▪ Damage is limited to the upper portion of the

vertebral body, particularly to the anterior margin

.

▪ Generally occur in the thoracic and lumbar

vertebrae, with the most common site being T11-

T12 in the thoracic spine and T12-L1 at the

thoracolumbar juncture

Hangmans fracture

Fracture of the arch of the second cervical

vertebra.

▪ Usually accompanied by anterior subluxation of

the second vertebra to the third cervical vertebra

.

▪ Sometimes referred to as “Traumatic spondylosis”

results from acute hyperextension of the head

Jefferson fracture

▪ “Burst fracture” of the first cervical vertebra (atlas)

.

▪ Generally occurs as a result of a severe axial force

that causes compression, as in a diving accident.

▪ The vertebral arch literally bursts.

▪ MRI – preferred imaging modality to best examine

the transverse longitudinal ligament

Fracture

▪ Discontinuity of bone caused by

mechanical forces either applied

to the bone or transmitted

directly along the line of a bon

Open fracture

one in which the

bone has penetrated the skin.

▪ This type of fracture leaves

an open route for bacteria to

enter from outside the body,

which may lead to infection

Closed fracture

A closed fracture

(formerly referred to as a

simple fracture)

▪ is one in which the skin is

not penetrated, which

reduces the chances of

infection

Impacted fracture

▪ When one of the fractured bone ends is jammed

into the cancellous tissue of another fragment.

Closed reduction

▪ Requires that a local or general anesthetic be given to the

patient for pain management.

▪ A splint or cast is then applied.

▪ Is required when orthopedic hardware is needed to maintain

fracture reduction or when an open fracture needs to be

irrigated.

▪ Generally, this is referred to as open reduction internal

fixation (ORIF)

Comminuted fracture

▪ Sometimes, one or more

fragments separate along the

edges of the major fragment in

addition to the major line of the

fracture.

▪ This is different from multiple

fractures.

Types: Butterfly fracture and

splintered fracture

Butterfly fracture

▪ A comminuted fracture in

which one or two butterfly

wing–shaped or wedge-

shaped fragments split off

from the main fragments

Splintered fracture

▪ A comminuted fracture

with long, sharp-pointed

fragments

Complete noncumminuted fracture

▪ One in which the bone has

separated into two

fragments.

▪ The fracture may be

recognized according to the

direction of the fracture line

Spiral or oblique fracture

▪ Such a fracture usually

results from a rotary type of

injury that twists the bone

apart and is particularly

common in the shafts of

long bones

Transverse fracture

is another type of complete,

Non comminuted fracture.

▪ Demonstrated

radiographically, such a

fracture through normal bone

is invariably ragged along the

fracture line

Pathologic fracture

▪ Commonly a transverse

fracture occurring in abnormal

bone that is weakened by

various diseases, such as a

bone cyst or metastatic bone

neoplasm.

▪ It may result from the disease

process itself or from a

relatively minor trauma

Avulsion fracture

Occur when a fragment of

bone is pulled away from

the shaft.

▪ Such fractures usually

occur around joints

because of ligament,

tendon, and muscle tearing,

as associated with a sprain

or dislocation

Chip fracture

Avulsion fx of a small

fragment or chip of bone

from the corner of a phalanx

or other long bone.

▪ These are very common in

the fingers and are often

tiny.

A mallet finger is an

example of this

Incomplete fracture

Only part of the bony structure

gives way, with little or no

displacement.

Greenstick fracture - The

cortex breaks on one side

without separation or

breaking of the opposing

cortex.

▪ The effect is similar to that of

trying to break a green twig,

hence its name

Torus fracture

▪ Commonly referred to as a buckle fracture, it is a greenstick

fracture in which the cortex bulges outward, usually in the

metaphysis, producing only a slight irregularity.

▪ Commonly found in the distal forearm or tibia-fibula after a fall

Penetrating fracture

A type of incomplete fracture resulting from penetration

by a sharp object such as a bullet or a knife

Stress fracture

▪ Usually occurs as a result of an abnormal degree of

repetitive trauma.

Fatigue fractures

Occur at sites of maximal strain on a bone, usually in

connection with unaccustomed activity.

▪ Found in the metatarsals, particularly the second

metatarsal—the classic “march” fracture

Colles fracture

A fracture through the

distal inch of the radius. The distal

fragment is usually angled backward

on the shaft, with impaction along

the dorsal aspect.

▪ Most common wrist fracture.

▪ Usually results from falling on an

outstretched hand.

▪ The external skin contour in a Colles

fracture displays a “dinner fork”

deformity

Smiths fracture

▪ Opposite of Colle’s fracture, with displacement of

the distal fragment toward the palmar aspect of

the hand.

▪ A direct blow or fall with the wrist in hyperflexion is

the usual mechanism of injury

Boxers fracture

Occurs when the fifth metacarpal (and occasionally the

fourth metacarpal) fractures as a result of a blow to or

with the hand

Bennet fracture

Fracture and dislocation of the first carpometacarpal joint

.

▪ The injury occurs when the thumb is forced backward

while in partial flexion and is commonly seen in basketball

players and skiers

Monteggia fracture

Fracture of the proximal third of the ulnar shaft, with

anterior dislocation of the radial head.

Galeazzi fracture

▪ Occurs at the proximal radius, with a dislocation of the

distal radial-ulnar joint

Dislocation/luxation

Results when a bone is out of its joint and not in

contact with its normal articulation

Subluxation

▪ A partial dislocation, often occurring with a fracture.

▪ The ankle and vertebral column, especially the

cervical spine, are common sites of subluxations

Battered child syndrome

Associated with a physical form of child abuse.

❑ No accidental trauma (NAT).

❑ bruises, burns, abrasions, and fractures in various stages of healing

❑ Radiographic skeletal surveys to include bones of the upper extremities, lower

extremities, skull, spine, and ribs

❑ Shaken baby syndrome – a severe type of abuse

Osteochondroma (Exostosis)

▪ Most common benign tumor:

femur or tibia.

▪ “Cauliflower”/ “Mushroom”

stalk appearance

Osteoma

Dense, well-

circumscribed; skull

- Hyperostosis

frontalis intern

Enchondroma

- Slow-growing

tumors; small bones

of the hands and feet

- “bubbly” lesiOn

Bone cyst

Wall of fibrous tissue filled with fluid

Osteoclastoma

Giant cell tumor

- “Soap bubble” appearancE

Osteosarcoma

▪ Highly aggressive

bone-forming neoplasm

▪ “Sunburst”/ “Sunray apperance

Ewing sarcoma

arises from the

medullary canal

▪ Gives rise to uniform

thickening of the bone

▪ “Onion peel/skin” sign

Chondrosarcoma

▪ Rare primary bone

cancer

▪ Cartilaginous origin

▪ Usually forms in the

pelvis, femur (thigh

bone), humerus

(upper arm bone),

and ribs.

W32767 : L 1

Osteolytic

loss of bone (destruction)

▪ Lucent, radiolucent, "punched-out" lesions

Osteoblastic

Osteoblastic

▪ -blastic = building bone (formation)

▪ Dense, sclerotic, radiopaque lesion