Term
| Reading Assignments: Chapter 26: Bones, Joints, and Soft Tissue Tumors |
|
Definition
|
|
Term
| Disorders associated with Osteonecrosis: Study Table 26-5 |
|
Definition
|
|
Term
| Histology and Immunopathogenesis of rheumatoid arthritis: Study Figures 26-42 and 26-44 |
|
Definition
|
|
Term
| Review the major pathogenetic pathways leading to primary and secondary hyperparathyroidism and the clinical features from the endocrinology lecture. |
|
Definition
|
|
Term
Fracture Healing:
Definition |
|
Definition
| The most common bone lesion is a fracture, which is defined as a discontinuity of bone. In the repair of a bone fracture, anything other than the formation of bone tissue at the fracture site represents incomplete healing. |
|
|
Term
| Three phases in the healing of a fracture: |
|
Definition
| Inflammatory, Reparative, Remodeling. |
|
|
Term
| Osteoblasts deposti Type 1 collagen in either: |
|
Definition
| in a random weave known as woven bone(?), or in an orderly layered manner, designated as lamellar bone. |
|
|
Term
|
Definition
| Normally, woven bone is seen in the fetal skeleton and is formed at growth plates. Its advantages are that it is produced quickly and resists forces equally from all directions. |
|
|
Term
| When is woven bone seen in an adult? |
|
Definition
| The presence of woven bone in the adult is always indicative of a pathologic state; however, it is not diagnostic of a particular disease. Woven bone is seen in pathologic states such as fracture, sites of infection (involucrum), and in the matrix of bone-forming tumors. |
|
|
Term
|
Definition
| Lamellar bone, which gradually replaces woven bone during growth, is deposited much more slowly and is stronger than woven bone. |
|
|
Term
|
Definition
| : Forces that are not excessive but fracture bone; bone is usually compromised by disease (e.g., tumors, hyperparathyroidism, osteoporosis, and Paget disease of bone) |
|
|
Term
|
Definition
| An inflammation of bone caused by bacterial infection |
|
|
Term
| Osteomyelitis: Most common cause: |
|
Definition
| The most common pathogens are Staphylococcus species. The most common cause is infection by direct penetration or extension of bacteria. |
|
|
Term
| Hematogenous osteomyelitis: def and most common site affected by this? |
|
Definition
| occurs when infectious organisms may reach the bone from a focus elsewhere in the body through the bloodstream. The most common sites affected by this mode of spread are the ends of the long bones, such as the knee, ankle, and hip. |
|
|
Term
|
Definition
| a fragment of necrotic bone that is embedded in pus |
|
|
Term
|
Definition
| refers to a lesion in which periosteal new bone formation forms a sheath around the necrotic sequestrum. |
|
|
Term
| Tuberculosis-Osteomyelitis of the vertebral body |
|
Definition
POTT DISEASE
In tuberculous osteomyelitis, the bone is destroyed by resorption of bony trabeculae, which results in mechanical collapse of the vertebrae and extrusion of the intervertebal disc. Tuberculous organisms cannot penetrate the intervertebral disc directly; rather, they extend from one vertebra to the next after mechanical forces destroy and extrude the intervertebral disc. |
|
|
Term
|
Definition
Degenerative Joint disease
Is a slowly progressive destruction of the articular cartilage that is manifested in the weight-bearing joints and fingers of older persons or the joints of younger persons subjected to trauma. |
|
|
Term
| Joints most commonly affected due to osteoarthritis? |
|
Definition
| the proximal and distal interphalangeal joints (PIP and DIP) of the upper extremity (hand), knees, hip, and the cervical and lumbar segments of the spine |
|
|
Term
|
Definition
| Large peripheral growths of bone and cartilage are called osteophytes which represent the bone's attempt to grow a new articular surface. |
|
|
Term
|
Definition
| In the fingers, osteophytes at the DIP are termed Heberden's nodes and Bouchard's nodes of the PIP. |
|
|
Term
| Denuded bone is described as |
|
Definition
|
|
Term
|
Definition
| Small fractures through the articulating bone are common, and the dislodged pieces of cartilage and subchondral bone tumble into the joint, forming loose bodies known as joint mice. |
|
|
Term
| Rheumatoid arthritis (RA) |
|
Definition
| A systemic, chronic, inflammatory disease with multiple, symmetric joint involvement. Systemic involvement with swelling of PIP and MCP (metacarpophalangeal) joints. Some 80% of patients with classic RA are positive for rheumatoid factor. |
|
|
Term
|
Definition
| a synovial lining thrown into numerous villi and frond-like folds that fill the peripheral recesses of the joint. The pannus erodes the articular cartilage and the adjacent bone, probably through the action of collagenase produced by the pannus. |
|
|
Term
|
Definition
| Hypercalcemia and hypophosphatemia are the characteristic biochemical abnormalities. Excessive PTH leads to excessive loss of calcium from the bones and enhanced calcium reabsorption by the renal tubules. The action of PTH on the kidney, together with the hypercalcemia, leads to hypophosphatemia. The classic bone lesions are known as osteitis fibrosa cystica. |
|
|
Term
| Primary hyperparathyroidism (HPTH) |
|
Definition
| An individual has persistent hypercalcemia and hypophosphatemia in primary HPTH. |
|
|
Term
| Secondary hyperparathyroidism |
|
Definition
| encountered principally in patients with chronic renal failure. Chronic hypocalcemia owing to the retention of phosphate (because of the inability of the kidney to secrete it) leads to a compensatory hypersecretion of PTH with bone lesions (osteitis fibrosa cystica). Thus, serum phosphate is elevated (hyperphosphatemia) and serum calcium is low (hypocalcemia). As a result, secondary hyperplasia of all four parathyroid glands occurs. There is osteoporosis. The serum calcium levels rise to balance the hyperphosphatemia. The elevated serum phosphate levels remain and then drive the elevated serum calcium back into the bone. There is now osteosclerosis of the bone. Additionally, in kidney failure, there is a reduction in vitamin D synthesis by the kidney. So, less vitamin D means less serum calcium. So, the bone is also undermineralized (osteomalacia). Many of these bone abnormalities continue to cycle back and forth until renal dialysis is instituted. This complex mixture of bone disease is known as renal osteodystrophy. With subsequent renal dialysis, the levels of serum calcium and phosphate are stabilized but the described abnormalities in the bone (renal osteodystrophy) remain and increase the risk of pathologic fracture. |
|
|
Term
|
Definition
| Is a metabolic bone disease characterized by diffuse skeletal lesions in which normally mineralized bone is decreased in mass to the point that it no longer provides adequate mechanical support. Regardless of the cause of osteoporosis, it always reflects enhanced bone resorption relative to formation |
|
|
Term
| Type 1 primary osteoporosis |
|
Definition
| due to an absolute increase in osteoclastic activity. The increased number of osteoclasts that appears in the early postmenopausal skeleton is the direct result of estrogen withdrawal. Linked to a number of factors that include genetics, calcium intake, calcium absorption and vitamin D, exercise, and environmental factors (cigarette smoking in women). African-American women are at lesser risk for osteoporosis than Caucasian or Asian women. |
|
|
Term
| Type 2 primary osteoporosis |
|
Definition
| (Senile osteoporosis in men and women) associated with aging and generally appears after age 70 and reflects attenuated osteoblast function. Thus, although osteoclast activity is no longer increased, any bone that is removed by osteoclasts is not replaced by osteoblasts. There is a relative resorption of bone, and thus, a net loss of bone. |
|
|
Term
| The most common sites for fractures occur in the weight-bearing bones such as |
|
Definition
| the hip, the vertebral bodies (compression fracture), and the distal radius (Colles fracture). |
|
|
Term
|
Definition
| exogenous corticosteroids, Cushing Disease, hyperthyroidism, hematologic malignancies, malabsorption, alcoholism. |
|
|
Term
|
Definition
(soft bones)
Is a disorder of adults characterized by inadequate mineralization of newly formed bone matrix. Rickets refers to a similar disorder in children, in whom the growth plates are open. The principal determinant of the formation of 1,25 (OH)2 vitamin D is the serum calcium concentration. A decrease in the level of blood calcium stimulates the release of PTH, which acts to augment the synthesis of this active form of vitamin D by the kidney. Hence, this active vitamin D regulates bone remodeling, and calcium uptake by the intestine to maintain calcium homeostasis in the blood. |
|
|
Term
| Freq causes of osteomalacia in the US? |
|
Definition
| Diseases of the small intestine (e.g., Crohn disease), cholestatic disorders of the liver, biliary tract obstruction, and chronic pancreatic insufficiency (How might these diseases be causative for osteomalacia |
|
|
Term
|
Definition
| a peculiar developmental abnormality of the skeleton characterized by a disorganized mixture of fibrous and osseous elements in the interior of affected bones with expansion of the cortical bone. It occurs in children or adults and may involve a single bone (monostotic) or many bones (polyostotic). In children, the expansion of bone usually stops after puberty. In 5% of cases, fibrous dysplasia is associated with endocrine dysfunction (e.g., acromegaly, Cushing syndrome) in which case the term McCune-Albright syndrome is applied. |
|
|
Term
| Common form of: fibrous dysplasia? |
|
Definition
| Monostotic is the more common form. Second and third decades without any predilection for either sex. Commonly involved bones include the proximal femur, tibia, ribs and facial bones. The disease may be asymptomatic or lead to pathologic fracture. |
|
|
Term
| Pathology of the bone due to fibrous dysplasia |
|
Definition
| . Lucent, ground glass appearance that is focal or diffuse. Benign fibroblastic tissue arranged in a whorled pattern with purposeless bone spicules (C-characters) that are not covered with a usual layer of osteoblasts. |
|
|
Term
|
Definition
(Osteitis deformans)
A chronic and common condition characterized by enlargement and lytic lesions of bone caused by disordered bone remodeling, in which excessive bone resorption initially results in lytic lesions, to be followed by disorganized and excessive bone formation. It generally affects men and women older than 60 years of age. Slow viral infection of osteoclasts may be involved in the pathogenesis. |
|
|
Term
| Paget Disease of Bone : bone involvement |
|
Definition
| : the bones of the axial skeleton, namely the spine, skull, and pelvis. The jaws may be grossly misshapen, and the teeth may be lost. Often, the facial bones increase in size, producing so-called leontiasis ossea (lion-like face). Complications include pagetic steal (shunting of blood from the internal carotid system to the bones rather than the brain), fractures, high output cardiac failure, and osteosarcoma. |
|
|
Term
|
Definition
| The most common primary malignant bone tumor, representing one-fifth of all bone cancers. It is most frequent in adolescents between the ages of 10 and 20 years, affecting boys more than girls (2:1). |
|
|
Term
| Osteosarcoma arises primarily in: |
|
Definition
vicinity of the knee, the lower femur, upper tibia, or fibula. Forms bone and is osteoblastic ("sun-burst" appearance on x-ray). Metastases through the blood stream to the lungs. Almost all patients (98%) who die of this disease have lung metastases.
NB. The most common malignant tumor of bone is metastatic cancer. Carcinomas compose the large majority of metastatic lesions to bone, specifically tumors of the breast, prostate, lung, thyroid, and kidney through hematogenous routes. |
|
|
Term
|
Definition
| Malignant tumors of plasma cells, occurring more in men than women (2:1). Lesions are almost exclusively lytic. The bones most frequently involved are the skull ("punched-out" lesions), spine, ribs, pelvis, and femur. Pathologic fractures are common. Review seminars and lectures pertaining to multiple myeloma from hematopathology. |
|
|
Term
|
Definition
| Endemic in tropical equatorial Africa and in parts of New Guinea. EBV is identified in the neoplastic cells in 95% of cases. Translocation of a portion of chromosome 8 to chromosome 14 is regularly observed; the C-myc gene is involved. The median age at onset is 7 years. Common sites of involvement include the jaw bones (maxilla and mandible) where the tumor is in the soft tissue, and abdominal sites such as the small bowel, kidneys, and ovaries. In the mandible or maxilla, the tumor mass is firm and the oral mucosa overlying the soft-tissue tumor mass is often hemorrhagic or ulcerated. Usually these masses are painless. Radiographs disclose massive lesions whereby the adjacent bone undergoes resorption with irregular margins and reactive bone occurring in the molar and premolar regions. Tooth displacement and root resorption are common. |
|
|
Term
| Histopathology of Burkitt Lymphoma |
|
Definition
| Lymph node shows a uniform infiltrate of medium-sized lymphoid cells, with scattered, benign macrophages, which impart a “starry-sky pattern”. |
|
|
Term
| Pathognomonic for Hyperparathyroidism |
|
Definition
|
|
Term
| Pathognomonic for Rickets |
|
Definition
| Bowing of Legs - indicator |
|
|
Term
| Pathognomonic for Paget’s Disease (viral infection of osteoclasts) |
|
Definition
Leonine facies; “Coot Wool”; Bowing of Legs (indicators);
Hallmark is a Mosaic Pattern of Lamellar Bones |
|
|
Term
| Pathognomonic for Osteosarcoma – Most Common PRIMARY malignant bone tumor; Paget Dz increases risk |
|
Definition
|
|
Term
| Pathognomonic for Osteogenesis Imperfecta / Dentinogenesis Imperfecta (Abnormal Dentin and Normal Enamel – Mesenchymal related disease) |
|
Definition
|
|
Term
| Pathognomonic for Osteoarthritis |
|
Definition
| Bouchard’s Nodes (Proximal Interphalangeal); Heberden’s Nodes (Distal Interphalangeal Joint) |
|
|
Term
| Pathognomonic for Rheumatoid Arthritis |
|
Definition
| Rheumatoid Factor (80% of time) - indicator |
|
|
Term
| Pathognomonic for Fibrous Dysplasia (developmental – disorganized mixture of fibrous and osseous elements in interior of bone with expansion of cortical) |
|
Definition
| Lucent, “Ground Glass” appearance – also seen with Hyperparathyroidism |
|
|
Term
|
Definition
| a discontinuity in bone structure due to a break in the cortical plates |
|
|
Term
|
Definition
| fractures are the most common lesions of bone |
|
|
