Medical Dictionary

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

ossiculum, pl .ossicula (o-sik′u-lum, -la) [TA]
SYN: ossicle. [L. dim. of os, bone] ossicula auditus [TA] SYN: auditory ossicles, under ossicle. ossicula mentalia small nodules of bone that appear at the symphysis menti shortly before birth and fuse with the mandible after birth.

ossiferous (o-sif′er-us)
Containing or producing bone. [ossi- + L. fero, to bear]

ossific (o-sif′ik)
Relating to a change into, or formation of, bone.

ossification (os′i-fi-ka′shun)
1. The formation of bone. 2. A change into bone. [L. ossificatio, fr. os, bone, + facio, to make] endochondral o. formation of osseous tissue by the replacement of calcified cartilage; long bones grow in length by endochondral o. at the epiphysial cartilage plate where osteoblasts form bone trabeculae on a framework of calcified cartilage. intramembranous o. SYN: membranous o.. membranous o. development of osseous tissue within mesenchymal tissue without prior cartilage formation, such as occurs in the frontal and parietal bones. SYN: intramembranous o.. metaplastic o. the formation of irregular foci of bone (sometimes including bone marrow) in various soft structures, such as the muscles, lungs, brain, and other sites where osseous tissue is abnormal.

ossiform (os′i-form)
SYN: osteoid (1) . [ossi- + L. forma, form]

ossify (os′i-fi)
To form bone or convert into bone. [ossi- + L. facio, to make]

ost-
See osteo-.

osteal (os′te-al)
SYN: osseous. [G. osteon, bone]

ostealgia (os-te-al′je-a)
Pain in a bone. SYN: osteodynia. [osteo- + G. algos, pain]

osteanagenesis (os′te-an-a-jen′e-sis)
SYN: osteoanagenesis.

osteanaphysis (os′te-a-naf′i-sis)
SYN: osteoanagenesis. [osteo- + G. anaphysis, a growing again]

ostectomy (os-tek′to-me)
1. Surgical removal of bone. 2. In dentistry, resection of supporting osseous structure to eliminate periodontal pockets. SYN: osteoectomy. [osteo- + G. ektome, excision]

ostein, osteine (os′te-in)
SYN: collagen. [G. osteon, bone]

osteitic (os-te-it′ik)
Relating to or affected by osteitis. SYN: ostitic.

osteitis (os-te-i′tis)
Inflammation of bone. SYN: ostitis. [osteo- + G. -itis, inflammation] alveolar o. SYN: alveoalgia. caseous o. tuberculous caries in bone. central o. 1. SYN: osteomyelitis. 2. SYN: endosteitis. o. condensans ilii (con-den′sanz il′e-i) symmetric benign osteosclerosis of the portion of the iliac bones adjacent to the sacroiliac joints. condensing o. SYN: sclerosing o.. cortical o. periostitis with involvement of the superficial layer of bone. o. deformans SYN: Paget disease (1) . o. fibrosa circumscripta SYN: monostotic fibrous dysplasia. o. fibrosa cystica increased osteoclastic resorption of calcified bone with replacement by fibrous tissue, caused by primary hyperparathyroidism or other causes of the rapid mobilization of mineral salts. SYN: parathyroid osteosis, Recklinghausen disease of bone. o. fibrosa disseminata SYN: polyostotic fibrous dysplasia. focal condensing o. SYN: chronic focal sclerosing osteomyelitis. hematogenous o. any o. caused by infection carried in the bloodstream. localized o. fibrosa SYN: monostotic fibrous dysplasia. multifocal o. fibrosa SYN: polyostotic fibrous dysplasia. o. pubis osteosclerosis of the pubic bone next to the symphysis, caused by trauma to that region, from pregnancy or instrumentation. renal o. fibrosa SYN: renal rickets. sclerosing o. fusiform thickening or increased density of bones, of unknown cause; it has been considered a form of chronic nonsuppurative osteomyelitis. SYN: condensing o., Garré disease. o. tuberculosa multiplex cystica an o. of tuberculous origin, marked by numerous small cavities in the osseous substance. SYN: Jüngling disease.

ostemia (os-te′me-a)
Congestion or hyperemia of a bone. [osteo- + G. haima, blood]

ostempyesis (os′tem-pi-e′sis)
Suppuration in bone. [osteo- + G. empyesis, suppuration]

osteo-, ost-, oste-
Bone. SEE ALSO: osseo-, ossi-. [G. osteon]

osteoanagenesis (os′te-o-an-a-jen′e-sis)
Regeneration of bone. SYN: osteanagenesis, osteanaphysis. [osteo- + G. ana, again, + genesis, generation]

osteoarthritis (os′te-o-ar-thri′tis)
Arthritis characterized by erosion of articular cartilage, either primary or secondary to trauma or other conditions, which becomes soft, frayed, and thinned with eburnation of subchondral bone and outgrowths of marginal osteophytes; pain and loss of function result; mainly affects weight-bearing joints, is more common in older persons. SYN: arthrosis (2) , degenerative arthritis, degenerative joint disease, osteoarthrosis. hyperplastic o. SYN: hypertrophic pulmonary osteoarthropathy.

osteoarthropathy (os′te-o-ar-throp′a-the)
A disorder affecting bones and joints. [osteo- + G. arthron, joint, + pathos, suffering] hypertrophic pulmonary o. expansion of the distal ends, or the entire shafts, of the long bones, sometimes with erosions of the articular cartilages and thickening and villous proliferation of the synovial membranes, and frequently clubbing of fingers; the disorder occurs in some chronic pulmonary diseases, in heart disease (most often congenital), and occasionally in other acute and chronic disorders. SYN: Bamberger-Marie disease, Bamberger-Marie syndrome, hyperplastic osteoarthritis, pneumogenic o., pulmonary o.. idiopathic hypertrophic o. o. not secondary to pulmonary or other progressive lesions, which may occur alone (acropathy) or as part of the syndrome of pachydermoperiostosis. pneumogenic o. SYN: hypertrophic pulmonary o.. pulmonary o. SYN: hypertrophic pulmonary o..

osteoarthrosis (os′te-o-ar-thro′sis)
SYN: osteoarthritis. [osteo- + G. arthron, joint, + -osis, condition]

osteoblast (os′te-o-blast)
A bone-forming cell that is derived from mesenchymal osteoprognitor cells and forms an osseous matrix in which it becomes enclosed as an osteocyte. SYN: osteoplast. [osteo- + G. blastos, germ]

osteoblastic (os′te-o-blas′tik)
Relating to the osteoblasts; describes any region of increased radiographic bone density, in particular, metastases that stimulate o. activity.

osteoblastoma (os′te-o-blas-to′ma)
An uncommon benign tumor of osteoblasts with areas of osteoid and calcified tissue, occurring most frequently in the spine of a young person. SYN: giant osteoid osteoma.

osteocalcin
A protein found in osteoblasts and dentin; contains γ-carboxyglutamyl residues; has a role in mineralization and calcium ion homeostasis. SYN: bone Gla protein.

osteocartilaginous (os′te-o-kar-ti-laj′i-nus)
SYN: osseocartilaginous.

osteochondritis (os′te-o-kon-dri′tis)
Inflammation of a bone and its overlying articular cartilage. [osteo- + G. chondros, cartilage, + -itis, inflammation] o. deformans juvenilis SYN: Legg-Calvé-Perthes disease. o. deformans juvenilis dorsi SYN: Scheuermann disease. o. dissecans complete or incomplete separation of a portion of joint cartilage and underlying bone, usually involving the knee, associated with epiphyseal aseptic necrosis. syphilitic o. inflammation of the epiphysial line associated with congenital syphilis. SYN: Wegner disease.

osteochondrodysplasia
SYN: camptomelic syndrome.

osteochondrodystrophia deformans (os′te-o-kon′dro-dis-tro′fe-a de-for′manz)
SYN: chondro-osteodystrophy.

osteochondrodystrophy (os′te-o-kon′dro-dis′tro-fe)
SYN: chondro-osteodystrophy.

osteochondroma (os′te-o-kon-dro′ma)
A benign cartilaginous neoplasm that consists of a pedicle of normal bone (protruding from the cortex) covered with a rim of proliferating cartilage cells; may originate from any bone that is preformed in cartilage, but is most frequent near the ends of long bones, usually in patients 10–25 years of age; the lesion is frequently not noticed, unless it is traumatized or of large size; multiple osteochondromas are inherited and referred to as hereditary multiple exostoses. SYN: solitary osteocartilaginous exostosis. [osteo- + G. chondros, cartilage, + -oma, tumor]

osteochondromatosis (os′te-o-kon-dro-ma-to′-sis)
SYN: hereditary multiple exostoses, under exostosis. synovial o. SYN: synovial chondromatosis.

osteochondrosarcoma (os′te-o-kon′dro-sar-ko′-ma)
Chondrosarcoma arising in bone. Sarcomas in bone containing foci of neoplastic cartilage as well as bone are classified as osteogenic sarcomas. [osteo- + G. chondros, cartilage, + sarx, flesh, + -oma, tumor]

osteochondrosis (os′te-o-kon-dro′sis)
Any of a group of disorders of one or more ossification centers in children, characterized by degeneration or aseptic necrosis followed by reossification; includes the various forms of epiphysial aseptic necrosis. [osteo- + G. chondros, cartilage, + -osis, condition]

osteochondrous (os′te-o-kon′drus)
SYN: osseocartilaginous. [osteo- + G. chondros, cartilage]

osteoclasis, osteoclasia (os′te-ok′la-sis, os′te-o-kla′ze-a)
Intentional fracture of a bone to correct deformity. SYN: diaclasis, diaclasia. [osteo- + G. klasis, fracture]

osteoclast (os′te-o-klast)
1. A large multinucleated cell, possibly of monocytic origin, with abundant acidophilic cytoplasm, functioning in the absorption and removal of osseous tissue. SYN: osteophage. 2. An instrument used to fracture a bone to correct a deformity. [osteo- + G. klastos, broken]

osteoclastic (os′te-o-klas′tik)
Pertaining to osteoclasts, especially with reference to their activity in the absorption and removal of osseous tissue.

osteoclastoma (os′te-o-klas-to′ma)
SYN: giant cell tumor of bone.

osteocranium (os′te-o-kra′ne-um)
The cranium of the fetus after ossification of the membranous cranium has made it firm. [osteo- + G. kranion, skull]

osteocystoma (os′te-o-sis-to′ma)
SYN: solitary bone cyst.

osteocyte (os′te-o-sit)
A cell of osseous tissue that occupies a lacuna and has cytoplasmic processes that extend into canaliculi and make contact by means of gap junctions with the processes of other osteocytes. SYN: bone cell, bone corpuscle, osseous cell. [osteo- + G. kytos, cell]

osteodentin (os′te-o-den′tin)
Rapidly formed tertiary dentin that contains entrapped odontoblasts and few dentinal tubules, thereby superficially resembling bone. [osteo- + L. dens, tooth]

osteodermatopoikilosis (os′te-o-der′ma-to-poy-ki-lo′sis) [MIM*166700]
Osteopoikilosis with skin lesions, most commonly small elastic fibrous nodules on the posterior aspects of the thighs and buttocks; irregular autosomal dominant inheritance. SYN: Buschke-Ollendorf syndrome. [osteo- + G. derma, skin, + poikilos, dappled, + -osis, condition]

osteodesmosis (os′te-o-dez-mo′sis)
Transformation of tendon into bony tissue. [osteo- + G. desmos, a band (tendon), + -osis, condition]

osteodiastasis (os′te-o-di-as′ta-sis)
Separation of two adjacent bones, as of the cranium. [osteo- + G. diastasis, a separation]

osteodynia (os-te-o-din′e-a)
SYN: ostealgia. [osteo- + G. odyne, pain]

osteodysplasty (os′te-o-dis′plas-te)
SYN: Melnick-Needles o.. SYN: Melnick-Needles syndrome. [osteo- + G. dys-, bad, + plastos, formed] Melnick-Needles o. a generalized skeletal dysplasia with prominent forehead and small mandible; radiographically, there are irregular ribbonlike constrictions of the ribs and tubular bones; probably X-linked [MIM*309350]. Autosomal dominant and recessive inheritance [MIM*249420] have also been suggested. SYN: o..

osteodystrophia (os′te-o-dis-tro′fe-a)
SYN: osteodystrophy.

osteodystrophy (os′te-o-dis′tro-fe)
Defective formation of bone. SYN: osteodystrophia. [osteo- + G. dys, difficult, imperfect, + trophe, nourishment] Albright hereditary o. an inherited form of hyperparathyroidism associated with ectopic calcification and ossification and skeletal defects, notably the small fourth metacarpals; intelligence may be normal or subnormal. Inheritance is heterogeneous; the autosomal form [MIM*103580] is caused by mutation in the guanine nucleotide-binding protein gene (GNAS1) on 20q. There are also the recessive [MIM*203330] and X-linked [MIM*300800] forms. SEE ALSO: pseudohypoparathyroidism. SYN: Albright syndrome (2) . renal o. generalized bone changes resembling osteomalacia and rickets or osteitis fibrosa, occurring in children or adults with chronic renal failure.

osteoectomy (os-te-o-ek′to-me)
SYN: ostectomy.

osteoepiphysis (os′te-o-e-pif′i-sis)
An epiphysis of a bone.

osteofibroma (os′te-o-fi-bro′ma)
A benign lesion of bone, probably not a true neoplasm, consisting chiefly of fairly dense, moderately cellular, fibrous connective tissue in which there are small foci of osteogenesis. Most examples of this condition, especially in the maxilla and mandible, probably represent foci of fibrous dysplasia; a few examples of fibrous lesions with foci of osteogenesis, especially in vertebral bodies, may be neoplasms.

osteofibrosis (os′te-o-fi-bro′sis)
Fibrosis of bone, mainly involving red bone marrow. periapical o. SYN: periapical cemental dysplasia.

osteogen (os′te-o-jen)
A bone matrix–producing tissue or layer. [osteo- + G. -gen, producing]

osteogenesis (os′te-o-jen′e-sis)
The formation of bone. SYN: osteogeny, osteosis (2) , ostosis (2) . [osteo- + G. genesis, production] distraction o. a technique of inducing new bone formation by dividing a bone and applying tension through an external fixation device to lengthen the bone. o. imperfecta (OI) a group of connective tissue disorders of type I collagen, characterized by bone fragility, fractures on trivial trauma, skeletal deformity, blue sclerae, ligament laxity, and hearing loss. The Sillence system, which is a clinical, radiographic, and genetic classification, shows four types; inherited as autosomal dominant, caused by mutation in either the collagen type I alpha-1 gene (COL1A1) on chromosome 17q or the alpha-2 gene (COL1A2) on 7q. SYN: brittle bones. o. imperfecta congenita a severe form [MIM 166230], with fractures occurring before or at birth. o. imperfecta tarda a less severe form, with fractures occurring later in childhood. Type I o. imperfecta [MIM*166200] a mild form characterized by blue sclerae, hearing loss, easy bruising, prepubertal bone fragility, and short stature. Type II o. imperfecta [MIM*166210] a perinatal lethal form associated with stillbirth or lifespan less than 1 year; very fragile connective tissue, and radiographic findings of in utero fractures, large soft cranium, micromelia, tubular long bones, and beaded ribs. Type III o. imperfecta [MIM*259420] a progressive deforming form with severe bone fragility, easy fractures, triangular facies with relative macrocephaly, skeletal deformities with scoliosis, pectus and bowing of limbs, dwarfism, and radiographic findings of metaphyseal flaring of long bones with sutural bone formation. Most cases are autosomal dominant disorders, but autosomal recessive inheritance has also been described. Type IV o. imperfecta [MIM*166220] a moderately severe form, characterized by short stature, bone fragility, preambulatory fractures, and bowing of long bones.

osteogenic, osteogenetic (os′te-o-jen′ik, -je-net′ik)
Relating to osteogenesis. SYN: osteogenous, osteoplastic (1) .

osteogenous (os-te-oj′e-nus)
SYN: osteogenic.

osteogeny (os-te-oj′e-ne)
SYN: osteogenesis.

osteography (os′te-og′ra-fe)
A treatise on or description of the bones. [osteo- + G. graphe, a writing]

osteohalisteresis (os′te-o-hal′is-ter-e′sis)
Softening of the bones through absorption or insufficient supply of the mineral portion. [osteo- + G. hals, salt, + steresis, privation]

osteohypertrophy (os′te-o-hi-per′tro-fe)
Condition characterized by overgrowth of bones. [osteo- + G. hyper- over, + trophe, nourishment]

osteoid (os′te-oyd)
1. Relating to or resembling bone. SYN: ossiform. 2. Newly formed organic bone matrix prior to calcification. [osteo- + G. eidos, resemblance]

osteolipochondroma (os′te-o-lip′o-kon-dro′ma)
A benign neoplasm of cartilaginous tissue, in which metaplasia occurs and foci of adipose cells and osseous tissue are formed. [osteo- + G. lipos, fat, + chondros, cartilage, + -oma, tumor]

osteologia (os-te-o-lo′je-a)
SYN: osteology, osteology. [L.]

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

. . . Feedback