XXI - Musculoskeletal System Flashcards
Known as “brittle bone disease”.
Osteogenesis Imperfecta (TOPNOTCH)Robbins Basic Pathology,8th ed., p802
This is a group of hereditary disorders caused by defective synthesis of type I collagen. Classic finding of a “blue sclerae” is seen in one type of this disorder.
Osteogenesis Imperfecta (TOPNOTCH)Robbins Basic Pathology,8th ed., p802
Characterized by , disproportionate shortening of the proximal extremities, bowing of the legs, and a lordotic (sway-backed) posture.
Achrondroplasia (TOPNOTCH)Robbins Basic Pathology,8th ed., p802
A group of rare genetic disorders characterized by reduced osteoclast-mediated bone resorption and therefore defective bone remodelling. Literally means “stone bone”.
Osteopetrosis(TOPNOTCH)Robbins Basic Pathology,8th ed., p802
The hallmark of this disease is loss of bone which tends to be most conspicuous in trabecular bone. The bony trabeculae are thinner and more widely separated than usual, resulting in an increased susceptibility to fractures.
Osteoporosis (TOPNOTCH)Robbins Basic Pathology,8th ed., p804
Characterized by repetitive episodes of frenzied, regional osteoclastic activity and bone resorption, followed by exuberant bone formation, and finally by an apparent exhaustion of cellular activity. Pathognomonic feature is a “mosaic pattern” of lamellar bone.
Paget Disease (Osteitis Deformans) (TOPNOTCH)Robbins Basic Pathology,8th ed., p806
The hallmark of this disease is increased osteoclastic activity, with bone resorption. This leads to characteristic radiographic changes best seen along the radial aspect of the middle phalanges of the second and third fingers.
Hyperparathyroidism (TOPNOTCH)Robbins Basic Pathology,8th ed., p808
Characterized by dead bone with empty lacunae is interspersed with areas of fat necrosis and insoluble calcium soaps. The cortex is usually not affected because of collateral blood supply.
Osteonecrosis (avascular necrosis)(TOPNOTCH)Robbins Basic Pathology,8th ed., p809
Inflammation of the bone and marrow cavity.
Osteomyelitis(TOPNOTCH)Robbins Basic Pathology,8th ed., p809
What do you call the dead entrapped bone seen in infected sites of bones affected with osteomyelitis?
Sequestrum(TOPNOTCH)Robbins Basic Pathology,8th ed., p809
What do you call the shell of living tissue around a segment of devitalized bone?
Involucrum (TOPNOTCH)Robbins Basic Pathology,8th ed., p809
Benign bone tumor characterized as exophytic growths attached to bone surface of the face and skull, which may histologically resemble normal bone.
Osteoma(TOPNOTCH)Robbins Basic Pathology,8th ed., p811
Benign bone tumor that are cortical tumors, histologically described as interlacing trabeculae of woven bone. Characteristic symptom is pain. Common locations include the metaphyses of the femur and tibia.
Osteoid osteoma(TOPNOTCH)Robbins Basic Pathology,8th ed., p811
These bone-forming lesions arise in vertebral transverse and spinous processes of the vertebral column, which may be histologically similar to osteoid osteoma.
Osteoblastoma(TOPNOTCH)Robbins Basic Pathology,8th ed., p811
A bone-producing malignant mesenchymal tumor, characterized as gritty, gray-white tumors, often exhibiting hemorrhage and cystic degeneration. The production of mineralized or unmineralized bone (osteoid) by malignant cells is essential for diagnosis.
Osteosarcomas(TOPNOTCH)Robbins Basic Pathology,8th ed., p811
These are relatively common benign hyaline cartilage-capped outgrowths attached by a bony stalk to the underlying skeleton.
Osteochondromas (TOPNOTCH)Robbins Basic Pathology,8th ed., p814
These are benign tumors of hyaline cartilage, described as gray-blue, translucent well-circumscribed nodules. May be seen in metaphyseal regions of tubular bones of the hands and feet. On x-ray, the unmineralized nodules of cartilage produce well-circumscribed oval lucencies surrounded by thin rims of radiodense bone (O-ring sign).
Enchondromas (TOPNOTCH)Robbins Basic Pathology,8th ed., p814
Chondromas seen on the bone surface.
Juxtacortical chondromas(TOPNOTCH)Robbins Basic Pathology,8th ed., p814
These lesions arise within the medullary cavity of the bone to form an expansile glistening mass that often erodes the cortex. They exhibit malignant hyaline and myxoid cartilage.
Conventional chondrosarcomas (TOPNOTCH)Robbins Basic Pathology,8th ed., p814
These tumors are characterized as viscous and gelatinous, with the matrix oozing from the cut surface. Spotty calcifications are typically present, with central necrosis creating cystic spaces.
Myxoid chondrosarcomas(TOPNOTCH)Robbins Basic Pathology,8th ed., p815
Presents as sharply demarcated radiolucencies surrounded by a thin zone of sclerosis. They are gray to yellow-brown, and microscopically are cellular lesions composed of cytologically benign fibroblasts and macrophages. The fibroblasts classically exhibit a “storiform (pinwheel) pattern”.
Fibrous Cortical Defect and Nonossifying Fibroma (TOPNOTCH)Robbins Basic Pathology,8th ed., p815
A benign tumor of the bone wherein all components of normal bone are present, but they fail to differentiate into mature structures. Curved trabeculae of woven bone mimick “Chinese characters” histologically.
Fibrous Dysplasia (TOPNOTCH)Robbins Basic Pathology,8th ed., p816
Primary malignant small round-cell tumor of bone and soft tissue, characterized by Sheets of small round cells with scant, cleared cytoplasm, circled about a central fibrillary space or “Homer-Wright rosettes”.
Ewing sarcoma (TOPNOTCH)Robbins Basic Pathology,8th ed., p817
A relatively uncommon benign tumor usually arising in individuals in their 20s to 40s. These are large and red-brown lesions with frequent cystic degeneration, composed of uniform oval mononuclear cells with frequent mitoses, with scattered osteoclast-type giant cells containing 100 or more nuclei.
Giant-cell tumors (GCTs)/Osteoclastoma(TOPNOTCH)Robbins Basic Pathology, 9th ed., p.1204
These are the most common malignant tumor of bone.
Metastatic tumors (TOPNOTCH)Robbins Basic Pathology,8th ed., p818
Pathways of metastasis to the bone.
1) direct extension, (2) lymphatic or hematogenous dissemination, (3) intraspinal seeding(TOPNOTCH)Robbins Basic Pathology,8th ed., p818
Characterized by fibrillation and cracking of the articular cartilage matrix, bone eburnation, and bony outgrowths/spurs (osteophytes). Full-thickness portions of the cartilage are lost, and the subchondral bone plate is exposed.
Osteoarthritis (TOPNOTCH)Robbins Basic Pathology,8th ed., p819
Characterized by a dense neutrophilic infiltrate permeating the synovium and synovial fluid. Long, slender, needle-shaped monosodium urate crystals are frequently found in the cytoplasm of the neutrophils as well as in small clusters in the synovium.
Acute gouty arthritis(TOPNOTCH)Robbins Basic Pathology,8th ed., p821
Results from repetitive precipitation of urate crystals during acute attacks. The synovium becomes hyperplastic, fibrotic, and thickened by inflammatory cells, forming a pannus that destroys the underlying cartilage.
Chronic tophaceous arthritis (TOPNOTCH)Robbins Basic Pathology,8th ed., p821
Formed by large aggregations of urate crystals surrounded by an intense inflammatory reaction of lymphocytes, macrophages, and foreign-body giant cells, attempting to engulf the masses of crystals. Pathognomonic feature of gout.
Tophi (TOPNOTCH)Robbins Basic Pathology,8th ed., p821
Refers to multiple different renal complications associated with urate deposition, variously forming medullary tophi, intratubular precipitations, or free uric acid crystals and renal calculi.
Gouty nephropathy(TOPNOTCH)Robbins Basic Pathology,8th ed., p821
Also known as chondrocalcinosis or-more formally-calcium pyrophosphate crystal deposition disease. The crystals are weakly birefringent, rhomboid in shape with blunted ends.
Pseudogout (TOPNOTCH)Robbins Basic Pathology,8th ed., p823
Main causative agent of suppurative arthritis in late adolescence and young adulthood.
Neisseria gonorrhea(TOPNOTCH)Robbins Basic Pathology,8th ed., p824
Individuals with sickle cell disease are prone to developing osteomyelitis and suppurative arthritis caused by this agent.
Salmonella(TOPNOTCH)Robbins Basic Pathology,8th ed., p824
Arthritis caused by infection with the spirochete Borrelia burgdorferi, transmitted by deer ticks of the Ixodes ricinus complex.
Lyme arthritis (TOPNOTCH)Robbins Basic Pathology,8th ed., p824
A small (
Ganglion cyst(TOPNOTCH)Robbins Basic Pathology,8th ed., p825
The most severe and the most common form of muscular dystrophy. Characterized by marked variation in muscle fiber size, caused by concomitant myofiber hypertrophy and atrophy. The definitive diagnosis is based on the demonstration of abnormal staining for “dystrophin” in immunohistochemical preparations.
Duchenne muscular dystrophy (DMD) (TOPNOTCH)Robbins Basic Pathology,8th ed., p825
This can present as either acute or chronic proximal muscle weakness, and can precede the onset of other signs of thyroid dysfunction. Findings include myofiber necrosis, regeneration, and interstitial lymphocytes.
Thyrotoxic myopathy (TOPNOTCH)Robbins Basic Pathology,8th ed., p830
This can occur with binge drinking, where there is an acute toxic rhabdomyolysis with accompanying myoglobinuria that can cause renal failure. On histology, there is myocyte swelling and necrosis, myophagocytosis, and regeneration.
Ethanol myopathy (TOPNOTCH)Robbins Basic Pathology,8th ed., p830
An autoimmune disorder of the neuromuscular junction characterized by muscle weakness which first manifests in the extraocular muscles. Caused by circulating antibodies to the skeletal muscle acetylcholine receptors (AChRs).
Myasthenia gravis (TOPNOTCH)Robbins Basic Pathology,8th ed., p830
This syndrome characteristically develops as a paraneoplastic process most commonly in the setting of small-cell lung carcinoma. Presents with muscle weakness secondary to decreased vesicle release in response to presynaptic action potential.
Lambert-Eaton Myasthenic Syndrome (TOPNOTCH)Robbins Basic Pathology,8th ed., p830
Soft tissue tumor which presents as soft, gelatinous, grapelike masses on the surfaces of the bladder or vagina.
Sarcoma botryoides(TOPNOTCH)Robbins Basic Pathology,8th ed., p830
It is the most common soft tissue sarcoma of childhood and adolescence, usually appearing before age 20.
Rhabdomyosarcoma (TOPNOTCH)Robbins Basic Pathology,8th ed., p831
Diagnostic cell in rhabdomyosarcoma, characterized as round or elongated cells that may contain cross-striations visible by light microscopy.
Tadpole or strap cells(TOPNOTCH)Robbins Basic Pathology,8th ed., p831
Soft, yellow, well-encapsulated masses of mature adipocytes; they can vary considerably in size. Histologically, they consist of mature white fat cells with no pleomorphism
Lipoma (TOPNOTCH)Robbins Basic Pathology,8th ed., p832
Malignant neoplasms of adipocytes, which usually present as relatively well-circumscribed lesions. Diagnostic feature are lipoblasta, similar to fetal fat cells, with cytoplasmic lipid vacuoles that scallop the nucleus.
Liposarcomas (TOPNOTCH)Robbins Basic Pathology,8th ed., p833
A self-limited, reactive fibroblastic proliferation that typically occurs in adults on the volar aspect of the forearm. Consists of plump, randomly arranged, immature-appearing fibroblasts in an abundant myxoid stroma. Not a true tumor.
Nodular Fasciitis(TOPNOTCH)Robbins Basic Pathology,8th ed., p833
This develops in the proximal muscles of the extremities in athletic adolescents and young adults after trauma. Distinguished from other fibroblastic proliferations by the presence of metaplastic bone. Excision is curative.
Myositis Ossificans (TOPNOTCH)Robbins Basic Pathology,8th ed., p833
Malignant neoplasms composed of fibroblasts. These are soft unencapsulated, infiltrative masses frequently with areas of hemorrhage and necrosis. Malignant spindle cells are arranged in a “herringbone pattern”.
Fibrosarcoma (TOPNOTCH)Robbins Basic Pathology,8th ed., p834
These are relatively common benign lesions in adults presenting as circumscribed, small (
Benign Fibrous Histiocytoma (Dermatofibroma) (TOPNOTCH)Robbins Basic Pathology,8th ed., p834
A variety of soft tissue sarcomas Characterized by considerable cytologic pleomorphism, the presence of bizarre multinucleate cells, and “storiform” architecture .
Malignant fibrous histiocytoma (MFH) (TOPNOTCH)Robbins Basic Pathology,8th ed., p834
Benign smooth muscle tumors described as well-circumscribed neoplasms that can arise from smooth muscle cells anywhere in the body, but are encountered most commonly in the uterus.
Leiomyoma (TOPNOTCH)Robbins Basic Pathology,8th ed., p835
These commonly present as firm, painless masses of the skin, deep soft tissues of the extermities and retroperitoneum. Histologically, they show spindle cells with cigar-shaped nuclei arranged in interweaving fascicles.
Leiomyosarcoma (TOPNOTCH)Robbins Basic Pathology,8th ed., p835
What is the mineral that gives bone strength and hardness and is the storehouse for 99% of the body’s calcium, 85% of the body’s phosphorous, and 65% of the body’s sodium and magnesium?
Calcium Hydroxyapatite (TOPNOTCH)
Of all the proteins in the bone matrix, which one is unique to the bone?
Osteocalcin (TOPNOTCH)
Identify the bone cell: responsible for bone resorption
Osteoclast (TOPNOTCH)