bone marrow (redirected from Bone marrow diseases)

bone marrow

n.

The soft, fatty, vascular tissue filling the cavities of bones, having a stroma of reticular fibers and cells.

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Bone marrow

A substance found in the cavities of bones, especially the long bones and the sternum (breast bone). The bone marrow contains those cells that are responsible for the production of the blood cells (red blood cells, white blood cells, and platelets).

Mentioned in: Aplastic Anemia, Bone Marrow Transplantation, Cancer Therapy, Supportive, Hairy Cell Leukemia, Immunologic Therapies, Leukemia Stains, Platelet Function Disorders, Porphyrias, Sickle Cell Disease, Thalassemia

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bone marrow

Etymology: AS, ban + ME, marowe

the soft, organic, spongelike material in the cavities of bones; also called medulla ossium. It is a network of blood vessels and special connective tissue fibers that hold together a composite of fat and blood-producing cells. Its chief function is to manufacture erythrocytes, leukocytes, and platelets. These blood cells normally do not enter the bloodstream until they are fully developed, so that the marrow contains cells in all stages of growth. If the body's demand for leukocytes is increased because of infection, the marrow responds immediately by stepping up production. The same is true if more erythrocytes are necessary, as in hemorrhage or anemia. Red marrow is found in many bones of infants and children and in the spongy (cancellous) bone of the proximal epiphyses of the humerus and femur and the sternum, ribs, and vertebral bodies of adults. Fatty yellow marrow is found in the medullary cavity of most adult long bones.

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bone,

n 1. the material of the skeletons of the tissue composing bones.
n 2. dense, hard, and slightly elastic connective tissue in which the fibers are impregnated with a form of calcium phosphate similar to hydroxyapatite.
3. the bones of the human skeleton.
n 4. a single element of the skeleton such as a rib or femur.

bone, alveolar

n the specialized bone structure that contains the alveoli or sockets of the teeth and supports the teeth.

bone, alveolar, architecture,

n the structural pattern of the alveolar bone and its subjacent latticework of supporting bone. The alveolar bone is thin and compact adjacent to the periodontal ligament. The trabecular bone connects and reinforces the individual alveoli. The architecture of a bone is the result of functional stimuli to that bone; the stimuli vary according to type, intensity, and duration.

bone, alveolar, metabolism,

n the metabolic activity occurring within alveolar bone, which is generally slower than that occurring within metaphyseal bone but more rapid than that of diaphyseal bone.

bone apposition,

n See bone deposition.

bone augmentation,

n a procedure used to build or enhance bone. It refers to either bone grafting or bone growing. Bone augmentation materials are classified as osseous, in which bone or bony substitutes are used to form new bone, or osseous conductive, in which these materials provide a platform for regeneration without taking part in actual bone formation.

bone, basal,

n the part of the mandible and maxilla from which the alveolar process develops.

bone, bundle,

n the bone forming the immediate bone attachment of the numerous bundles of collagen fibers of the periodontal ligament that have been incorporated into the bone.

bone bur,

n a drill designed to cut into bone.

bone, cadaver,

n bone that has been donated for medical purposes from one person to another; used especially in bone grafting procedures. See also allogenic and allografts.

bone calcium content,

n the amount of calcium stored in bone tissue. Plasma calcium is in constant exchange with the calcium of the extracellular fluid and bones. The parathyroid gland maintains the constancy of the calcium concentration in the plasma. The bones serve as a reservoir of calcium and phosphate to provide for the other needs of the body and supply minerals for deposition in the skeleton.

bone, cancellous (spongy bone, supporting bone, trabecular bone),

n the bone that forms a trabecular network, surrounds marrow spaces that may contain either fatty or hematopoietic tissue, lies subjacent to the cortical bone, and makes up the main portion of a bone.

bone, cancellous, atrophy of disuse

n the wasting of bone tissue occurring with loss of function of a part (e.g., a tooth). The supporting bone assumes an osteoporotic nature, and the marrow remains fatty or hematopoietic.

bone cells,

n.pl the group includes osteoblasts, osteocytes, osteoclasts, and osteoprogenitor cells.

bone changes, mechanical factors,

n.pl the pressure and tension forces that play an important role in determining bone structure. Improperly controlled appliances can resorb bone faster than deposition can occur, causing mobile teeth and traumatic occlusion. Poor vascularity is a concomitant cause of undue pressure and tension and may inhibit repair and cause necrosis.

bone chips,

n.pl the small pieces of cancellous bone generally used to fill in bony defects and precipitate recalcification.

bone, compact,

n the hard, dense bone composing the outer cortical layer and consisting of periosteal bone, endosteal bone, and haversian systems.

bone conduction,

n See conduction, bone.

bone crest,

n the most coronal portion of alveolar bone.

bone cyst,

n 1. a vascular cyst eccentrically placed within a bone.
n 2. ostitis fibrosa cystica, a parathyroid disorder characterized by cyst formation and the replacement of bone tissue with fibrous connective tissue.

bone defects, angular,

n.pl the usually localized anomalies that occur in the crestal bone as the result of both periodontal inflammation and occlusive trauma.

bone density,

n the compactness of bone tissue. The demonstration of bone density by means of radiographs directly depends on the quantity of inorganic salts contained in the bone tissue.

bone deposition,

n the apposition or formation of new bone as a normal physiologic process.

bone development,

n B See bone, endochondral, formation; bone formation; and bone, intramembranous, formation.

bone, effect of external radiation to,

n damage to the bones of adults is most often seen after heavy and localized radiation treatment.

bone, endochondral

n a bone that is developed in relation to antecedent cartilages (e.g., long bones, mandible). See also bone, intramembranous.

bone, endochondral, formation,

n a replacement of previously formed embryonic cartilage with an adult bony structure. The actual replacement of cartilage by bone is only part of the process, however; much of the bone is laid down directly external to the embryonic cartilage. See also bone, membrane, formation.

bone formation,

n the deposition of an organic mucopolysaccharide matrix (osteoid) that is subsequently mineralized with calcium salts. See also bone apposition and bone deposition.

bone graft, autogenous

n See graft, autogenous bone.

bone graft, donor site,

n See donor site.

bone graft, onlay,

n See graft, onlay bone.

bone graft, recipient site,

n See recipient site.

bone groove,

n an osteotomy into or near the crest of the alveolar ridge for placement of an endosteal blade type of implant.

bone groove, canted,

n an osteotomy sloped to avoid the mandibular canal or keep the implant infrastructure within the medullary confines.

bone, horizontal loss of,

n a resorption of bone caused by periodontal inflammation in which the bone crest remains even with the cementoenamel junctions of two adjoining teeth. The condition may be localized or generalized.

Horizontal bone loss.

bone, internal reconstruction of,

n the formation of bone on the tensional side of the periodontal ligament with concurrent resorption from the marrow space; contralaterally, resorption of alveolar bone with apposition from the endosteum in the marrow space.

bone, interproximal,

n the bone that forms the septa between the teeth; consists primarily of a spongy supporting bone covered by a layer of cortical bone. See also septum, interdental.

bone, intramembranous,

n a bone developed within a membrane but having no associated cartilage (e.g., parietal, frontal, bones of upper face). See also bone, endochondral.

bone, intramembranous, formation,

n membrane bone forms directly from the mesenchyme, first as a thin, flattened, irregular bony plate or membrane in the dermis and gradually expanding at its margins and becoming thickened by the deposition of successive layers of additional bone on the inner and outer surfaces. See also bone, endochondral, formation.

bone involvement,

n changes in the alveolar and supporting bone occurring as a sequel to or accompanying inflammatory or dystrophic disease; usually of a resorptive nature.

n the small, fragile, paired facial bone that helps form a part of the orbital wall and also a small part of the nasal cavity. The bone has four borders and two surfaces that articulate with four other facial bones.

bone lamella,

n bone having the appearance of layers of thin leaves or plates. This appearance is produced by lines representing periods of inactivity of bone formation.

bone, malar (zygomatic bone), frontal process of,

n a prominence on the zygomatic bone (cheekbone) that forms the anterior lateral orbital wall.

n a prominence on the zygomatic bone (cheekbone) that forms part of the inferior rim of the orbit and a small part of the orbital wall.

n a prominence on the inferior aspect of the zygomatic bone (cheekbone) that articulates with the zygomatic process of temporal bone to form the zygomatic arch.

bone, marble,

n See osteopetrosis.

bone marrow,

n the soft vascular tissue that fills bone cavities and cancellous bone spaces and consists primarily of fat cells, hematopoietic cells, and osteogenetic reticular cells.

bone marrow transplant,

n the transplantation of bone marrow from healthy donors to stimulate production of formed blood cells. It is used in treatment of hematopoietic or lymphoreticular diseases such as aplastic anemia, leukemia, immune deficiency syndromes, and acute radiation syndrome.

bone membranes,

n.pl the membrane structures associated with the growth, development, and repair of bone. They include the periosteum, a connective tissue layer adjacent to bone surfaces; periodontal ligament, a modified periosteum associated with tooth structure; and endosteum, a thin layer of connective tissue lining the walls of the bone marrow spaces.

bone, microscopic appearance of,

n the composition of bone tissue as viewed under a microscope. Microscopically, bone is composed of osteocytes embedded within lacunae in a calcified intercellular matrix. Extending from the lacunae are small canals called canaliculi, which communicate with canaliculi of adjacent lacunae. Through this system of canals, nutrient material reaches the osteocytes and provides avenues for the removal of waste products of metabolism. It is deposited in incremental layers (lamellae) around haversian canals, the lamellae toward the surface of the bone being more or less parallel to it.

bone mineral content, chemistry of,

n the hardness of bone results from its mineral content in the organic matrix. The minerals (commonly designated as bone salts) and the organic matrix make up the interstitial substance of bone. The bone salts consist essentially of hydroxyapatite (Ca₁₀[PO₄]₆[OH₂]), carbon dioxide, and water, with small amounts of other ions.

bone morphogenetic protein (BMP),

n See protein, bone morphogenetic (BMP).

bone, normal level of,

n the distance from the interdental bone crest to the cementoenamel junction in healthy teeth, usually 1 to 1.5 mm.

n the saucer-shaped cranial bone that forms the most posterior part of the skull; the spinal cord passes through the foramen magnum, an opening at its base.

bone onlay,

n See graft, onlay bone.

bone, perichondrial

n bone that is deposited in concentric layers around the long shaft of the bone in a manner similar to that of the growth of endochondral bone.

bone, physical properties of,

n a compact bone has the following physical characteristics: specific gravity, 1.92 to 1.99; tensile strength, 13,000 to 17,000 psi; compressive strength, 18,000 to 24,000 psi; compressive strength parallel to the long axis, 7150 psi; compressive strength at right angles to the long axis, 10,800 psi. These physical characteristics make bone particularly suitable for carrying out its functions of weight bearing, leverage, and protection of vulnerable viscera.

bone rarefaction

n a decreased density of bone such as a decrease in weight per unit of volume.

bone recession,

n See recession, bone.

bone, resorption and repair of,

n an adaptive physiologic mechanism occurring as long as the individual retains the natural dentition. See also resorption of bone.

bone, resting lines in,

n.pl the regular lines created by alternating periods of bone formation and rest, giving a tierlike appearance to lamellar bone.

bone, reversal lines in,

n.pl the irregular lines containing concavities directed away from the bundle bone and serving as histologic indications that resorption has taken place up to that line from the marrow side.

bone sequestrum,

n See sequestrum.

bone, spongy,

n See bone, cancellous.

bone support,

n the amount of alveolar and trabecular bone adjacent to a tooth that can provide attachment, investment, and support for the tooth.

bone, supporting,

n See bone, cancellous.

bone, supporting, atrophy of disuse,

n See bone, cancellous, atrophy of disuse.

bone surgery,

n See surgery, osseous.

bone, thickened margin of,

n the widening of the crest of the alveolus, primarily on the buccal and lingual aspects, varying from a thick ledge to a “beading” of the bone margin; results in a more or less bulbous contour of the gingival tissue overlying it.

bone, trabecular

n See bone, cancellous.

bone, vertical loss of,

n a resorption of bone caused by periodontal inflammation and occlusal trauma in which the bone crest is below the cementoenamel junctions of two adjoining teeth. It can be localized (mainly) or generalized.

bone, vertical plates of the palatine,

n the thin, oblong-shaped bone with two surfaces and four borders. It helps to form the floor of the orbit, the outer wall of the nasal cavity, and several adjoining structures.

bone volume (mass), age-affecting,

n decreases that occur in human body bone mass after age 40. Diet and exercise may be contributing factors.

bone wax,

n See wax, bone.

bone, woven,

n a character and pattern of bone resulting from the interweaving of broad bands of bone.

bone(s), cranial,

n the eight bones that make up the skull and protect the brain and include the ethmoid, frontal, occipital, sphenoid, two parietal, and two temporal bones.

bone(s), facial,

n the 14 bones that include the mandible, maxilla, frontal bones, nasal bones, and zygoma. With the exception of the mandible, maxilla, and vomer bones, the bones of the face occur in pairs, thus accounting for facial symmetry. They provide the framework for the face, serve as entry points for the digestive and respiratory systems, and provide the attachments for the muscles controlling facial expression.

bone(s), horizontal plates of palatine,

n the bones that form the posterior part of the hard palate and consist of four borders and two surfaces.

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bone marrow

the soft, organic material in the cavities of bones, a network of blood vessels and special connective tissue fibers that hold together a composite of fat and blood-producing cells.

The chief function of bone marrow is to manufacture erythrocytes, leukocytes and platelets. These blood cells normally do not enter the bloodstream until they are fully developed, so that the bone marrow contains cells in all stages of development. If the body's demand for white cells is increased because of infection, the bone marrow responds immediately by increasing production. The same is true if more red blood cells are needed, as in hemorrhage or anemia.

There are two types of bone marrow, red and yellow. The former produces the blood cells; the latter, which is mainly formed of fatty tissue, normally has no blood cell-producing function.

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bone marrow aplasia

any of the three cell lines may be singularly aplastic but a pancytopenic abnormality is most common. See also aplastic anemia.

bone marrow aspiration

see bone marrow biopsy.

congenital bone marrow hypoplasia

see osteopetrosis.

bone marrow-derived cells

see B lymphocyte.

bone marrow displacement

see myelophthisis.

bone marrow dyscrasia

abnormal cell production by the bone marrow. Occurs in some dog breeds, especially Poodles, in which there are maturation abnormalities of erythrocytes with macrocytosis and hypersegmented neutrophils.

bone marrow spaces

the cavities in cancellous bone that are usually filled with bone marrow.

bone marrow suppression

some drugs and infectious agents can cause reduced erythropoiesis, myelopoiesis and megakaryocytopoiesis. See also anemia, pancytopenia.

toxic bone marrow arrest

see resurgence granulopoiesis.

bone marrow transplantation

the transfer of bone marrow from a normal, antigenically matched individual to another, usually for treatment of aplastic anemia, immunodeficiency or metabolic disorders.

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Patient discussion about Bone marrow diseases.

Q. What is Leukemia? My brother's best friend has been diagnosed with Leukemia. What is it? Is it dangerous? Can you recover from it?

A. Leukemia is the general name for four different types of blood cancers. In people with leukemia, the bone marrow produces abnormal white blood cells. The abnormal cells are leukemia cells. At first, leukemia cells function almost normally. In time, they may crowd out normal white blood cells, red blood cells, and platelets. This makes it hard for blood to do its work. After diagnosis, many people with leukemia do survive and live many good, quality years. The relative five-year survival rate has more than tripled in the past 47 years for patients with leukemia. In 1960-63, when compared to a person without leukemia, a patient had a 14 percent chance of living five years. By 1975-77, the five year relative survival rate had jumped to 35 percent, and in 1996-2003 the overall relative survival rate was nearly 50 percent.

Q. What is a bone marrow transplant? I wanted to enter myself as a potential bone marrow donor and wanted to know first of all what bone marrow is? What does a bone marrow transplant mean and how is it done?

A. Bone marrow is a soft, fatty tissue inside the bones. This is where blood cells are produced, and where they develop. Transplanted bone marrow will restore production of white blood cells, red blood cells, and platelets. Donated bone marrow must match the patient's tissue type. It can be taken from the patient, a living relative (usually a brother or a sister), or from an unrelated donor. Donors are matched through special blood tests called HLA tissue typing. Bone marrow is taken from the donor in the operating room while the donor is unconscious and pain-free (under general anesthesia). Some of the donor's bone marrow is removed from the top of the hip bone. The bone marrow is filtered, treated, and transplanted immediately or frozen and stored for later use. Transplant marrow is transfused into the patient through a vein (IV) and is naturally carried into the bone cavities where it grows to replace the old bone marrow.