Musculoskeletal disorders Pt. III Flashcards
How much of lyme arthritis cases go untreated in the US?
60-80%
What organs are affected by lyme arthritis and what are the general symptoms?
Multiple organs. Fever, lymphadenopathy.
What kind of lesion is associated with lyme arthritis?
Erythema chronicum migrans
What is the Dx for lyme arthritis?
IgG and IgM in serum
What happens in later stages of lyme arthritis?
Joint destruction, migratory joint pain
What are the 3 stages of lyme arthritis?
Spirochete multiplication
Early dissemination
Late dissemination (2-3 years after infxn)
What are two phenomenon associated with the late dissemination phase of lyme arthritis?
A. Chronic polyarthritis: knee, shoulder, elbow, ankle
B. Encephalitis: mild-to-severe
What are examples of SOLs (4)
Blood, pus, tumor, edema
T/F
With SOLs primary joint neoplasms are rare
True
What is the definition of cyst?
epithelium-lined cavity in the body, containing
liquid or semisolid material*
What are some SOL tumor-like lesions?
Ganglion
Synovial cyst
What kind of cyst is a ganglion cyst?
Small myxoid cyst. Degenerative connective tissue
Where are ganglion cysts found?
Wrist: joint capsule/tendon space`
What is the tx for ganglion cysts?
compression, aspiration, “Bible therapy”
What is a synovial cyst?
Benign, synovial herniation through joint capsule
What are Baker’s cysts?
Popliteal cysts
What are tenosynovial giant cell tumors (TGCT)
A group of benign synovial tumors (previously thought ot be reactive lesions)
What is a diffuse TGCT?
(pigmented villonodular synovitis) Large, nodular mass in the joint synovium. Pain, ↓ ROM, joint locking, edema. Possible erosion of surrounding soft or bony tissues
What is a localized TGCT?
(GCT of tendon sheath)
• Small, solitary, tendon sheath nodule (hand: wrist, fingers)
• Well-circumscribed/localized, painless mass
Where are diffuse TGCTs found?
Knee MC (80%), hip, ankle
What is considered “soft tissue”
Any non-epithelial tissue, excluding: bone,
cartilage, CNS, hematopoietic, lymphoid tissue, adipose, fibrous, muscle, vessels, PNS
Soft tissue tumors are MC benign except when they are found where?
In skeletal muscle
What is the MC location for a soft tissue tumor?
Thigh
When do soft tissue tumors have a worse diagnosis?
When they are deeper/larger
What are lipomas?
Benign tumor of adipocytes. MC soft tissue tumor of adults.
• Solitary, painless, mobile, slow growing
What is a liposarcoma?
Malignant tumor of adipocytes. • Deep soft tissues: retroperitoneum, thigh
• Variable aggressiveness, possible mets (lungs)
What is nodular faciitis
Nodular fasciitis: reactive fibroblastic mass
• Non-neoplastic, self-limited
What locations is nodular faciitis found and what are some features noted? What is the Dx?
Possibly painful, solitary, rapid growth, 10-15% trauma
• Adults, volar (palm-side) arm, chest, back
Excision is necessary if painful
What is myocitis ossificans
Reactive, metaplastic bone
• Hard/painless mass, distinct borders
Among whom is myocitis ossificans found and in what locations?
- Proximal extremity muscles (MC)
* Adolescent athletes, 2° to trauma
What is the primary differential Dx for myocitis ossificans?
Osteosarcoma (age, osteoblastic)
What is fibromatosis?
Benign, but locally invasive fibroblastic proliferation
What are the features of a fibromatosis?
Disfiguring, painful, commonly recur
Where are superficial fibromatoses found and what are some conditions identified with it?
superficial fascia, deformation
• Dupuytren contracture, Peyronie disease - (MC: 40-70 yrs.)
What are and where are deep fibromatoses found?
(desmoid tumors): MC abdominal
• Rarely outside abdomen
What are some features of deep fibromatoses and what conditions are identified with it?
- Aggressive, locally destructive, recur
* Gardner syndrome: multiple deep fibromatoses intestinal polyposis, osteomas
What is the Tx for fibromatoses?
Watchful waiting, excision, chemo., irradiation
What are fibrosarcomas?
- Malignant, slow growing, but destructive
* Present for years prior to diagnosis
Where are fibrosarcomas found and among which age group?
Deep tissues • Thigh, retroperitoneum, knee Originates in fibrous tissue → invades bone • Femur, tibia, mandible • Adults: 35-55 years old
What are some features of fibrosarcomas?
Fibroblasts & anaplastic spindle cells
• Unencapsulated, infiltrative
What cytological finding is indicative of fibrosarcomas?
Herringbone pattern
What percent of fibrosarcomas have mets? What metastatic pathway does it prefer and where does it MC spread to?
25% have hematogenous mets: MC lungs
T/F
Fibrosarcomas generally do not occur again after excision?
False
50% recur after excision
T/F
Virtually all skeletal muscle tumors are malignant
True
What areas are most prone to rhabdomyosarcomas?
Areas with little skeletal muscle
• Head/neck (40%), genitourinary (25%),
extremities (20%), trunk (7%)*
What is the MC pediatric soft tissue sarcoma
Rhabdomyosarcoma
T/F
Rhabdomyosarcomas have a highly regular/identifiable appearance?
False,
Highly variable appearance
What kind of prognosis is generally found with cases of rhabdomyosarcomas?
2/3 are cured (adults: poor prognosis)
Where is a leimyoma found and what are some features?
benign
• Common, well-circumscribed
• Anywhere with smooth muscle cells: Uterus (MC, “fibroids”), small bowel, esophagus
What are leiomyosarcomas?
Malignant
• Adults females (MC), firm painless mass
Where are leiomyosarcomas found?
Deep: extremities, retroperitoneum (IVC)
What are some telling cytological characteristics with leiomyosarcomas?
Spindle cells, cigar-shaped nuclei
• Superficial/smaller = better prognosis
What are synovial sarcomas and what age group is most susceptible?
Aggressive/invasive, painless mass
• Any age, MC between 20-40 years
T/F
Synovial sarcomas MC are found in joints
False
The name is misleading. <10% are intra-articular
Where are synovial sarcomas found?
Deep soft tissues, near larger extremity joints
• MC Knee: 60-70% of cases
Where do synovial sarcomas tend to have mets to?
Lung, bone, lymph nodes
What is the tx for synovial sarcomas?
Limb sparing surgery (like osetosarcomas) and chemo
What is the MC congenital disorder of the limbs?
Syndactyly
What kind of bone is most affected by osteoporosis
Spongy, trabecular bone
What kind of appearance is Paget’s disease said to have?
“shaggy appearance”
What 3 pathologies can present an ivory vertebra sign on imaging?
Prostate Cancer (metastatic)
Paget’s disease
Lymphoma
What are some common features of hyperparathyroidism?
Renal stones (MC), peptic ulcers, pathologic, Fx, bowing of long bones
Multiple hereditary osteochondromas increase the risk for what condition?
Increase sarcoma risk (<1%)
What two conditions present with a ring of sclerosis “O ring sign”?
OO and chondroma
Who is most at risk for developing a chondrosarcoma?
40-60 yr old male
If a chondrosarcoma has an increased translucency on x-ray, what does this mean?
Increase risk of a high grade
NOFs increase risk for what?
Fracture
What mutations do all forms of Fibrodyslasia come from?
Spontaneous GNAS mutations
What condition has upon histological examination will look like chinese writing?
Polyostotic fibrodysplasia
