Mcphs Mmd Ii Final Exam Bone Cancers

Front 1

The most common site of origin is in the metaphyseal areas of long bone. Distal femur is the most common location for this.

Back 1

Osteosarcoma

Front 2

Growth of tumor occurs in radial manner creating a ball-like mass.

When it penetrates the bone, it compresses surrounding muscles forming a pseudocapsular layer called the "reactive zone".

Tumor nodules "satellites" invade the reactive zone

Tumors growing outside of the reactive zone but within the same bone or across a neighboring joint are called "skip lesions".

Back 2

Osteosarcoma

Front 3

Where is the most common place for metasttases with osteosarcoma?

Back 3

The lungs are the most common systemic location of metastases followed by distant bone.

Front 4

What are the manifestations of osteosarcoma?

Back 4

Bone pain is the most common symptom

Referred pain especially in children

Fever, night sweats, weight loss

Front 5

On radiographic studies, this manifests as mixed sclerotic and lytic lesions.

Pulmonary metastases appears as chest nodules or "cannonball" lesions.

Back 5

Osteosarcoma

Front 6

Disappearance of tumor vascularity after preoperative chemotherapy is associated with a better prognosis with this disease?

Back 6

Osteosarcoma

Front 7

What is required to diagnose and stage osteosarcoma?

Back 7

Biopsy is required for diagnosis

Conventional osteosarcomas are composed of spindle cells that produce osteoid

Front 8

What is involved with the management of osteosarcoma?

Back 8

Chemotherapy - Most regimens include Doxorubicin (Adriamycin) and Cisplatin (Platinol), with or without high dose methotrexate.

Surgery - Limb salvage = resection of the tumor with reconstruction of a functional extremity.

If adequate limb sparing resection can't be performed then amputation should be considered.

Front 9

Tumors consisting of cartilage based histology with absence of osteoid formation.

Usually presents in adults between the ages of 30-60 years old.

Metaphysis is the most common location.

The pelvis and the femur are the most common sites followed by ribs, proximal humerus, scapula and upper tibia.

Back 9

Primary Chondrosarcoma

Front 10

This typically presents a chronic aching pain over period of years.

Matrix calcification described as flocculated.

Back 10

Primary Chondrosarcoma

Front 11

What is the primary treatment for primary chondrosarcoma?

Back 11

Surgical resection

Front 12

This usually shows up between the ages of 5-25

More common in boys/men

Whites more frequently affected

Back 12

Ewing Sarcoma

Front 13

This is associated with a reciprocal translocation between chromosomes 11 and 22 in > 90% of cases

Tends to occur in the diaphysis of long bones and in the flat bones of the body

Lower extremity is the most common location followed by the pelvis, upper extremity, axial skeleton, ribs and face

Back 13

Ewing Sarcoma

Front 14

What are the manifestations with Ewing Sarcoma?

Back 14

Bone pain - Usually weeks to months, and may be accompanied by paresthesias.

Tenderness

Palpable Mass

Fever, night sweats, weight loss

Front 15

This shows up on plain film radiograph with what?

Radiolucent and lytic, layered periosteal calcification "onion skinning"

"Hair on End" appearance due to bone forming along periosteal vessels that run perpendicular between the cortex and elevated periosteum

Back 15

Ewing Sarcoma

Front 16

What has to be done in order to confirm the diagnosis of Ewing Sarcoma?

Back 16

Biopsy

Labs:
Elevated WBC
Elevated ESR
Elevated Lactate Dehydrogenase = with severity of tumor

Front 17

What is the TX for Ewing Sarcoma?

Back 17

Treatment includes surgical resection, radiation, chemotherapy

Front 18

The following are systemic factors contributing to what?

DM, Immunosuppression, including people receiving chronic steroids, immune disease, malnutrition, renal/hepatic failure, chronic hypoxia

Back 18

Osteomyelitis

Front 19

The following are local factors contributing to what?

PVD, Venous Stasis Disease, Chronic Lymphedema, Radiation Fibrosis, Arteritis, Neuropathy, Tobacco Use

Back 19

Osteomyelitis

Front 20

This is identified within 7-14 days of onset.

Most often associated with hematogenous seeding of the metaphysis in the long bones of children.

Adults may develop acute hematogenous infections around implanted prosthesis.

Back 20

Acute Osteomyelitis

Front 21

Infants less than one year old often have acute osteomyelitis from what pathogens?

Back 21

Group B Strep

Staph aureus

E. Coli

Front 22

Children 1-6 years old often have acute osteomyelitis from what pathogens?

Back 22

Staph aureus

Staph pyogenes

H. Influenza

Front 23

Adults over 16 years of age often have acute osteomyelitis from what pathogens?

Back 23

Staph epidermis

Staph aureus

P. aeruginosa

E. coli

Front 24

How does acute osteomyelitis usually manifest?

Back 24

Acute inflammation usually present

Localized pain but may radiate to adjacent areas

Localized tenderness

Systemic signs: Fever/Chills, Irritability, Lethargy

Front 25

What is involved with the work up of acute osteomyelitis?

Back 25

Labs - WBC, ESR, CRP

Cultures - Wound Culture, pus on aspiration, Blood Culture

Front 26

These may be normal in the early stages of acute osteomyelitis?

Back 26

X-Rays

Approximately 1-2 weeks X-Rays may reveal radiolucent lesions, (osteolysis) periosteal elevation and sequestra (separated segments of necrotic bone)

Front 27

What is the gold standard for diagnosing acute osteomyelitis?

Back 27

Bone Biopsy

Front 28

What are three things involved with the TX of acute osteomyelitis?

Back 28

ABX

Debridement

Bone Stabilization

Front 29

What is the empirical TX you start a patient on after collecting cultures on acute osteomyelitis?

Back 29

Nafcillin plus either Ceftriaxone or Cefotaxime

Front 30

This is more common in pediatric patients.

X-Rays may show mix of areas of osteolysis and periostial elevation (acute) and reactive sclerotic bone (chronic)

Treatment follows the same as acute osteomyelitis

Back 30

Subacute Osteomyelitis

Front 31

This may be categorized into gonococcal and nongonococcal bacterial infections.

Back 31

Septic Arthritis

Front 32

The following are risk factors for what?
Age > 80 years
Diabetes Mellitus
Pre-existing RA
Presence of a Prosthetic Joint
Recent Joint Surgery
Skin Infection
Impaired Immune System
Patients on Dialysis
IVDA

Back 32

Septic Arthritis

Front 33

What is the most common cause of a septic joint?

Back 33

It is by hematogenous seeding of a joint from an extra-articular infection.

Pneumonia, Pyelonephritis, Skin Infection

Front 34

Direct inoculation of a pathogen into a joint is a less common presentation of septic arthritis. What can cause this?

Back 34

Cat bites: Pasteurella

Puncture Wound through shoes: Pseudomonas

Front 35

Majority of nongonococcal septic arthritis cases are caused by what two things?

Back 35

Gram Positive Cocci

Gram Negative Bacilli (more common in the elderly)

Front 36

This is the most common organism in native and prosthetic joint infections associated with septic arthritis?

Back 36

Staph aureus

Front 37

This causes septic arthritis in prosthetic joints but not in native joints?

Back 37

Staph epidermidis

Front 38

What is the gold standard for diagnosing septic arthritis?

Back 38

Arthrocentesis with synovial fluid analysis is gold standard

Front 39

What is required when testing the synovial fluid for septic arthritis?

Back 39

Cell count, gram stain, wet prep examination for crystals under polarized microscopy and culture

Front 40

When you have septic arthritis what does the synovial fluid from arthrocentesis look like?

Back 40

Fluid is usually purulent

High WBC count with increased polymorphonuclear cells

Front 41

What is the empirical TX for septic arthritis?

Back 41

Nafcillin or Oxacillin with Ceftriaxone, Ceftizoxime, or Cefotaxime

Front 42

Apart from regular empirical TX for septic arthritis, what should be added to a pt who is an IV drug user?

Back 42

Aminoglycoside

Front 43

If a patient has MRSA septic arthritis, what should nafcillin/oxacillin be substituted with?

Back 43

Vancomycin

Front 44

How do you TX Gram-Positive Cocci in Clusters in septic arthritis

Back 44

Nafcillin or Oxacillin
Add Aminoglycoside if patient is IVDA

Front 45

Gram-Positive Cocci in Chains in septic arthritis

Back 45

Nafcillin or Oxacillin

Front 46

How do you TX Gram-Negative Bacilli in septic arthritis

Back 46

Nafcillin or Oxacillin/Aminoglycoside

Front 47

How do you TX Gram-Negative Diplococci in septic arthritis

Back 47

Ceftriaxone or Cefotaxime

Front 48

Presents as a Monoarticular joint infection in >90% of cases
The knee and hip joints are most commonly affected
Most likely pathogens include S. aureus, Group B streptococcus and gram negative organisms
Gonorrhea needs to be considered in any sexually active adolescent
Higher risk of avascular necrosis in septic arthritis of the femoral head

Back 48

Septic Arthritis in Children

Front 49

Caused by Neisseria gonorrhoeae
Should be considered in any sexually active person and represents Disseminated Gonococcal Infection
Women are more susceptible than men
Positive GC cultures at extra-articular sites (throat, GU, rectum) helps to confirm the diagnosis
Treatment is usually with a third generation Cephalosporin (Ceftriaxone)
Residual joint sequelae is rare

Back 49

Gonococcal Joint Infections