Term
| pain usually indicates what kind of pathology? |
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Definition
| fracture or osteonecrosis |
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Term
| systemic sx usually indicates what kind of path? |
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Definition
| metastatic cancer or metabolic bone disease |
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Term
| localized sx usually indicates what kind of path? |
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Definition
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Term
| elevated alkaline phosphatase activity (increased osteoblast activity) indicates what disease? |
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Definition
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Term
| define compound fracture, comminuted fracture, displaced fracture, pathologic fracture, stress fracture |
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Definition
| compound (site communicates with skin), comminuted (splintered, multiple pieces), displaced (ends of bone not aligned), pathologic (occurs in a bone already altered by a disease process), stress (develops slowly in a bone subjected to repetitive loads as in sports training) |
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Term
| how is achondroplasia acquired? |
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Definition
| hereditary, autosomal dominant.80% due to mutations |
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Term
| what are the pathology and clinical features of achondroplasia? |
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Definition
| premature obliteration of growth plates --> shortened proximal extremities (with normal trunk, enlarged head, bulging forehead) --> dwarfism. (homozygous achondroplasia leads to death at or son after birth d/t respiratory insufficiency secondary to small thorax) |
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Term
| what is the pathogenesis of osteogenesis imperfecta? |
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Definition
| type I collagen abnormaltiy --> increased bone fragility (brittle bone disease) --> skeletal fragility, mult frac & joint laxity, blue sclera, hearing impairment, teeth and skin changes |
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Term
| what is the pathogenesis behind osteomalacia/ricketts? |
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Definition
| defect in hydroxyapatite formation of bone (either lack of Ca or lack of phosphate. low vit D? renal disease? (peeing out phosphate)) |
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Term
| what is a long-term effect of osteogenesis imperfecta? |
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Definition
| multiple microfractures over a prolonged period of time --> bent bones --> dwarfism |
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Term
| whats the pathogenesis behind osteopetrosis? |
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Definition
| abnormal osteoclast activity (d/t carbonic anhydrase type II deficiency) --> increased bone radiodensity, lack of medullary canal (bones get stuck in calcified cartilage bc not capable of absorbing the calcified cart of the growth plate) --> stone-like bone quality, abnormally weak, fractures easily, bulbous ends of long bones, neural foramina narrow and compress exiting nerves (blindness, deafness, paresis) |
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Term
| what are the 3 types of osteopetrosis? |
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Definition
| infantile-malignant (autosomal recessive), intermediate (autosomal recessive), autosomal dominant (bone marrow transplant necessary) |
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Term
| what are the most common organisms causing osteomyelitis? |
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Definition
| staph and strep cause pyogenic osteomyelitis, and TB causes granulomatous inflammation |
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Term
| describe the pathogenesis of osteomyelitis |
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Definition
| infective organisms gain access to bone marrow (via bacteremia, direct expansion from adjacent focus of inf, or compound fracture) -->inflammation spreads within shaft of the bone through haversian system --> reaches periosteum --> subperiosteal abscesses --> segmental bone necrosis --> rupture of periosteum --> new periosteal bone formation |
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Term
| what are the joints most likely to be affected by osteomyelitis? |
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Definition
| big bones - femur, humerus |
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Term
| what part of the bone would we see osteonecrosis in adults? childreN? |
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Definition
| in adults, metaphysis, diaphysis, or subchondral region of epiphysis. in children (idiopathic) epiphysis of growing children |
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Term
| what would we observe in the bone with osteonecrosis? |
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Definition
| cloudy marrow, dont see discrete adipose cells, bone has pallor, devoid of osteocyte nuclei, lots of lacunar space with no osteocyte |
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Term
| whats the peak age and location for osteochondroma? |
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Definition
| 2nd decade, distal femur - metaphyseal location |
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Term
| what is the pathophysiology of osteochondroma? |
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Definition
| perichondrial proliferation of cartilage with transformation into bone (cartilage pushes out and forms its own center of ossification) looks like mature bone with cartilaginous cap. grows in direction of muscle pull, away from the joint. rarely can have malignant transformation into chondrosarcoma. |
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Term
| enchondroma peak age and common site of occurance. |
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Definition
| 2nd decade, small bones of hands/feet, femur, humerus (in medullary cavity, i.e. inside bone) |
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Term
| chondroblastoma (aka giant cell tumor) peak age and common location |
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Definition
| 2nd decade, proximal humerus, distal femur, proximal tibia (in epiphysis or on apophysis) |
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Term
| what is the most common presenting feature of giant cell tumor (chondroblastoma)? |
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Definition
| pain predating the dx by mos or yrs |
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Term
| chondromyxoid fibroma peak age and common location |
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Definition
| 2nd and 3rd decade, around knee in eccentric metaphyseal location w/sharp sclerotic and scalloped margins |
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Term
| histology of osteochondroma |
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Definition
| mimicks normal growth plate |
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Term
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Definition
| hypocellular tumor, blue-gray cartilagenous matrix, small nuclei, rare binucleation |
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Term
| chondroblastoma histology |
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Definition
| pink-blue fibrochondroid islands and multinucleated giant cells scattered randomly in a sea of mononuclear cells |
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Term
| histology of chondromyxoid fibroma |
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Definition
| distinct lobular growth pattern with peripheral hypercellularity and hypocellular spindled and stellate cells in the chondromyxoid central portion of the lesion |
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Term
| chondrosarcoma peak age and common locations |
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Definition
| adulthood (3-6 decade), acetabular region, central skeleton, vertebrae, proximal femur, proximal humerus, intermedullary in metaphysis or diaphysis |
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Term
| histology of chondrosarcoma |
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Definition
| homogenous blue-gray tumor with lobules of myxoid and hyaline cartilage, hypercellular with pleomorphism, hyperchromatism and frequent binucleation of cells (mitotic, bizarre cells, disorganization) |
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Term
| describe where you'd normally find an osteoma and what it'd look like on an xray |
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Definition
| radiodense mass projecting from subperiosteal or endosteal surfaces of cortex. nearly always in skull or nasal sinuses --> impinge on brain or eye |
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Term
| osteoid osteoma peak age and common location |
|
Definition
| 2nd decade, proximal femur and femoral neck in cortex of diaphysis |
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Term
| clinical presentation of osteoid osteoma |
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Definition
| pain of increasing severity, worse at night and relieved with aspirin |
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Term
| osteoblastoma peak age and common location |
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Definition
| 2nd decade, vertebrae (central lesion vs. appendicular skeleton involvement in osteoid osteoma) |
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Term
| clinical presentation of osteoblastoma |
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Definition
| pain of long duration, not relieved with aspirin; possible neurological defecit d/t vertebral tumor compressing the cord or nerve roots. |
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Term
| histology of osteoid osteoma vs osteoblastoma |
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Definition
| common features: interlacing network of thin osteoid trabeculae, haphazardly arranged, interspersed loose fibrovascular CT rimmed by oblasts. difference: osteoid osteoma <2cm; osteoblastoma >2cm |
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Term
| how does an osteoid osteoma look on xray |
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Definition
| small round lucency with surrounding sclerosis |
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Term
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Definition
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Term
| osteosarcoma peak age and common location |
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Definition
| bimodal distribution (2nd decade - 75%; in elderly secondary to paget's, bone infarcts or radiation); distal femur, proximal tibia, metaphysis of long bones |
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Term
| radiographic hallmark of osteosarcoma |
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Definition
| tumors frequently break through cortex and lift the periosteum (codman's triangle" |
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Term
|
Definition
| surgical resection and chemotherapy |
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Term
| describe simple bone cysts, where they occur and how they resolve |
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Definition
| first 2 decades of life, common dev abn, occur at end of long bones (diaphysis of prox humerus, prox femur and prox tibia), can be left alone bc theyre small and go away on their own, can tx with curettage and bone grafting |
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Term
| describe aneurysmal bone cysts, where they occur and how they resolve |
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Definition
| 2nd decade, vertebrae femur tibia (any bone though), rapidly growing blood-filled cystic mass in metaphysis of long bones, tx is surgical removal |
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Term
| what is thought to cause non-ossifying fibromas and where are they located |
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Definition
| related to insertion of a tendon/lig into the perichondrium of the epiphyseal growth plate. located on circumference of metaphysis of long tubular bones (distal femur, prox tibia) |
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Term
| what is the etiology of fibrous dysplasia? |
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Definition
| developmental disorder causing delayed development of normal bone. can be monostotic or polyostotic, when its polyostotic it may be assoc with endocrine dysfunction (sexual precocity, hyperthyroidism, pituitary adenomas, primary adrenal hyperplasia), also possibly d/t abnormalities in the G protein pathway that stimulates cyclic AMP |
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Term
| polyostotic fibrous dysplasia is typically associated with? |
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Definition
| endocrinopathy and cafe-au-lait skin pigmentation, involves shoulder and pelvic girdles and can result in crippling deformities (shepherd's crook deformity aka angular defect in proximal femur d/t femur sustaining mult fractures). mccune-albright syndrome if assoc with cafe-au-lait |
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Term
| what are 2 common clinical problems with fibrous dysplasia? |
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Definition
| bulging (d/t bone expansion) and resulting pathologic fracture |
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Term
| fibrosarcoma peak age and common location |
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Definition
| broad range 2-8 decade, metaphyseal or diaphyseal distal femur and proximal tibia. cortical destruction with extension in to adjacent soft tissue |
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Term
| histology of fibrosarcoma |
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Definition
| malignant fibroblasts arranged in herringbone pattern |
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Term
| ewings sarcoma peak age and location |
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Definition
| 2nd decade, medullary cavity of pelvic girdle and diaphysis of long tubular bones of lower extremities |
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Term
| classic presentation of ewings sarcoma on xray |
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Definition
|
|
Term
| etiology of ewings sarcoma |
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Definition
| chromosomal translocation t(11:22) |
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Term
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Definition
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Term
| giant cell tumor peak age and common location |
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Definition
| 3rd decade, distal femur prox tibia dist radius and sacrum |
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Term
| pigmented villonodular synovitis peak age/sex/location |
|
Definition
| 3-4 decade, women, knee (80%) hip (15%) |
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Term
| describe the pathophysiology and sx of pigmented villonodular synovitis |
|
Definition
| locally destructive fibrohistiocytic proliferation --> innumerable villous and nodular synovial protrusions (may have hemosiderin which gives it a pigment) --> pain, progressive swelling, bloody effusions worsening further the increasing limitation of range of motion |
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Term
| tx for pigmented villonodular synovitis |
|
Definition
| surgical excision, but high recurrence rate |
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Term
| common locations for synovial sarcoma |
|
Definition
| extremities (knee most common) arising in vicinity of joints, bursae, and tendon sheaths, metastasizes to lungs, lymph nodes, skin, abdomen, bone, brain |
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