Tumors and Infections Flashcards
What are the 5 most common primary sites of cancer that metastasize to bone?
Breast
Lung
Kidney
Thyroid
Prostate
Most Common Malignancy of Bone
Metastases
Most common Primary Malignancy of Bone
Myeloma
Most Common Primary Sarcoma of Bone
Osteosarcoma
Benign tumor that involves the cortex and expands into the medullary cavity. Lytic with well-defined and lobulated margins.
Nonossyfying Fibroma
Where are Nonossyfying Fibromas most commonly found?
Femur
Tibia
Benign tumor that is sclerotic and presents with a small < 1cm Lucent nidus
- best seen on CT
Osteoid Osteoma
Signs and Symptoms of Osteoid Osteoma
Night Pain
- responsive to NSAIDs
Where are Osteoid Osteomas most commonly found?
Long Bones
Posterior Spine
Treatment for Osteoid Osteoma
Self-limited
Non-surgical
Benign and progressive tumor that may be lytic, sclerotic, or mixed.
Radiolucent nidus > 2cm
Big Brother to Osteoid Osteoma
Osteoblastoma
Osteoblastoma Signs and Symptoms
Dull ache
- not relieved by NSAIDs
Osteoblastoma Treatment
Surgery
Bone arising from stalk (pedunculated) or “bump” on bone that is benign. Occurs on the metaphysis of long bones usually in childhood and young adults.
Osteochondroma
Benign lytic bone expansion. Can occur on any bone and has a ground glass appearance on X-Ray.
Fibrous Dysplasia
Radiolucent, well-defined, confined to the cortex with a sclerotic border. Benign.
Fibrous Cortical Defect
Where are Fibrous Cortical Defects most commonly found?
Distal Femur
Tibia
Benign lytic lesion that may erode beyond the cortex. Can metastasize to the lungs, even though it is benign.
Giant Cell Tumor
Where are Giant Cell Tumors most commonly found?
Distal Femur
Proximal Tibia
Distal Radius
Proximal Humerus
Pelvis
Sacrum
A benign vascular tumor of bone.
Honey-comb appearance
Jail Bar Appearance
Hemangioma
Most common primary bone malignancy. Usually has localized bone pain (ribs or spine) or pathologic fractures.
X-Rays show “Punched Out” Lesions
Multiple Myeloma
Who does Multiple Myeloma most Commonly Effect?
Males > 40
African Americans
What are 2 significant findings of Multiple Myeloma?
Bence Jones Proteins
- proteinuria
Hypercalcemia
- due to bone destruction
Malignancy that causes callous formations.
Osteosarcoma
What is the most common site of Metastasis of Osteosarcoma?
Lungs
How is osteosarcoma treated?
Multi-Agent Chemotherapy
+
Limb Salvage Resection
What pathogen is the primary cause of Osteomyelitis?
Staph. aureus
- 60% of cases
What are common causes that allow for Osteomyelitis?
Open Fracture
Surgery
Open Wound
Hematogenous Spread
Signs of an Epidural Abscess with Vertebral Osteomyelitis
Fever
Severe Back or Neck Pain
Radicular Symptoms
Incontinence
What are the most common locations of Osteomyelitis?
Long Bones
Vertebrae
If a patient is an IV drug abuser, what are the most likely sites of Osteomyelitis?
- SPINE
But also:
2. Sternoclavicular Joint
3. Sacroiliac Joint
Signs and Symptoms of Hematogenous Osteomyelitis
Sudden Onset of Fever
Chills
Pain
Tenderness
Causes of Contiguous Osteomyelitis
Prosthetic Joint
Orthopedic Surgery
Causes of Vascular Insufficiency Osteomyelitis
Diabetes
- foot and ankle are most common
What are 2 clues of Osteomyelitis in Ulcers?
Easily able to advance probe to the Bone
Ulcer area > 2cm
If testing for Osteomyelitis, why should you get the cultures from the bone or blood and not from the overlying wounds or ulcers?
Wounds or ulcers are unreliable due to contamination with skin flora.
Osteomyelitis Treatment
IV ABX (4 - 6 weeks)
- MRSA → Vancomycin
- MSSA → Cefazolin. Oxacillin. Nafcillin.
When does Osteomyelitis require Surgery?
- Epidural Abscess
- Extensive Disease
- Recurrent or Persistent Infection
Acute onset of inflammatory monoarticular arthritis, most often in large weight-bearing joints and wrists.
Septic Arthritis
(Non-gonococcal acute bacterial arthritis)
What is the most common pathogen to cause of Septic Arthritis?
Staph. aureus
What are the most common causes of Septic Arthritis in IV Drug Abusers?
E. coli
Pseudomonas
Joints are usually in what position with Septic Arthritis due to effusion?
Flexion
Abduction
What are the hallmarks of Septic Arthritis?
Joint Tenderness
Effusion
Erythema
Marked Limitation of Passive Motion
What tests should be performed on a patient with Septic Arthritis?
Labs
Ultrasound
Joint Fluid Aspiration
Cultures
Gonococcal → Throat, Cervical, and Urethral Cultures
What might a AP/Lateral X-Ray show in a patient with Septic Arthritis?
Usually Normal
- maybe soft tissue swelling with widened joint space
What would an Ultrasound show in a patient with Septic Arthritis?
Joint Effusion
Why should you perform an MRI with Septic Arthritis?
Rule Out Osteomyelitis
Septic Arthritis Treatment
Vancomycin + Ceftriaxone until cultures return
Emergent Surgical Decompression and Lavage
- Cornerstone of Treatment
Arthritis that is common is MSM → higher incidence of asymptomatic gonococcal pharyngitis and proctitis predisposes them to disseminated infection.
Women 2-3x > men
- especially during menses and pregnancy
Typically occurs in healthy persons.
Gonococcal Arthritis
Signs and Symptoms of Gonococcal Arthritis
1 - 4 days of migratory polyarthralgias
- Tenosynovitis (60%)
- Purulent Monoarthritis (40%)
Most have asymptomatic skin lesions
Best Test for Gonococcal Arthritis
Urinary NAAT
Gonococcal Arthritis Treatment
Ceftriaxone (1g IV or IM)
- change to oral agent with 7 day course
- Responds DRAMATICALLY to ABX
