SEARCH · PubMed Health

Results for “Tibia”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 919 records · Page 51Linked to original sources

PubMed2005

[Effects of surface potentials of tooth hard tissue on bone remodeling in rabbit tibiae].

OBJECTIVE: To investigate the influence of surface potentials of tooth hard tissue on bone remodeling. METHODS: After insured the surface potentials of human extracted teeth with electrochemical methods, teeth sections and artificial hydroxyapatite were implanted into 25 rabbits' tibiae. The rabbits were sacrificed at 1, 2, 4, 6 and 8 weeks after implantation, respectively. The bone regeneration was compared between opposite two sides (cathode side and anode side) of tooth sections using hematoxylin-eosin (HE) staining, tartrate-resistant acid phosphatase (TRAP) activity detecting and tetracycline tracing method. RESULTS: Resorption lacunae was seen in the tibiae facing to the enamel anode and new bone density in the implant bed near the cathode of tooth samples was much higher than that near the anode, while the number of TRAP positive cells near the cathode was smaller than that near the anode (P < 0.01). The fluorescent area of tetracycline tracing near the cathode was larger than that near the anode (P < 0.05). CONCLUSIONS: The cathode of tooth hard tissue (cementum) could improve or trigger new bone formation, while the other side, anode (enamel), could improve the bone resorption. This study suggests that tooth hard tissue's electrochemical characteristic might affect the remodeling of alveolar bone, and tooth supraeruption and the alveolar bone loss after tooth extraction might result from the redundant or lack of root electrochemical stimulation to bone.

Alveolar Bone Loss↗

PubMed2005

Age ranges of epiphyseal fusion in the distal tibia and fibula of contemporary males and females.

The range of variation in epiphyseal fusion in North American populations has not been sufficiently established. This significant oversight can lead to exclusion of persons of interest in a forensic investigation. This study evaluates epiphyseal fusion of the distal tibia and fibula in 570 European-, African-, and Mexican-American children and young adults. Radiographs of 270 females aged 9 to 17 and 300 males aged 11 to 20 were analyzed to assess the range of variation of epiphyseal fusion at each age. Results indicate that complete fusion in females occurs as early as 12 years in the distal tibia and fibula. All females demonstrated complete fusion by 16 years with no significant differences between ancestral groups. Complete fusion in males occurs as early as 14 years in both epiphyses. All males demonstrated complete fusion by 19 years. Significant differences in the earliest age of complete fusion showed that African- and Mexican-American males demonstrate complete fusion as early as 14 years in both epiphyses while European-American males do not express complete fusion until 16 years.

Adolescent↗

PubMed2006

CAD method for three-dimensional model of the tibia bone and study of stresses using the finite element method.

In the real life, the leg and its skeleton are exposed at the most diverse stresses. It is known that the human bone is one of the most important natural composite materials. The paper presents a method of study and the steps to obtain the virtual bones of the human body, method applied to tibia bone. For that purpose was used a CAD parametric software which permits to define models with a high level of complexity. To obtain the bone cross sections of the tibia bone a Computer Tomograph was used. The obtained 3D model is studied using the finite element method, taking into consideration the real structure of the bone and the mechanical characteristics of cortical and spongy, and we can obtain the stresses distribution for different solicitation.

Biomechanical Phenomena↗

PubMed1991

The effects of paralysis on skeletal development in the chick embryo. II. Effects on histogenesis of the tibia.

In order to study the effects of paralysis on the development of bone, chick embryos were paralysed at 6 days of incubation and the pattern of histogenesis of the tibia was compared with that of control embryos by histology, scanning electron microscopy and morphometry. Up to 11 days of incubation the histological features of chondrification, initial perichondrial ossification and invasion by the vascular bud showed no differences. After this time the paralysed embryos exhibited a reduction in the formation of bone tissue and a reduced development of the fibular crest. The spread of cartilage resorption was also markedly reduced. In addition, scanning electron microscopy suggested a reduction in resorption of the innermost layers of bone. Blood vessels in the marrow cavity appeared smaller and those within developing osteones appeared larger than in the controls. In the paralysed embryos, morphometry confirmed a significant reduction in total volume of the tibia together with changes in its volumetric composition resulting from reduction in bone formation, cartilage formation and cartilage resorption.

Animals↗

PubMed1991

The orientation of the mineral crystals in the radius and tibia of the sheep, and its variation with age.

The direction of preferred orientation of the hydroxyapatite crystals in both the tibia and radius of the sheep is close to the long axis of the bone, notwithstanding the angle of about 30 degrees which, for the tibia, exists between the long axis and the direction of principal dynamic strain during locomotion. For both bones the orientation of the cranial cortex, which is a tension surface during locomotion, is about 40% larger than the caudal. The variation with age of the magnitude of the preferred orientation for the sheep bones is contrasted with what has been reported earlier for the human femur. Notably, for the sheep, both bones show substantial orientation at birth--having increased steadily during gestation--so that the animal is able to stand and walk at the outset.

Aging↗

PubMed1991

Suppression of prostaglandin E2 synthesis in the membrane surrounding particulate polymethylmethacrylate in the rabbit tibia.

Fifteen mature, New Zealand, female rabbits were divided into two groups. Using sterile technique, a 6-mm drill hole was made in the tibia 1 cm distal to the knee joint bilaterally. The marrow was scooped out underneath the hole. The right tibia received Simplex particulate cement polymer and the left leg functioned as a prepared, but nonimplanted, control. All animals were fed a standard diet. Whereas the six animals in Group 1 received regular water, the nine animals in Group 2 drank water in which sodium naproxen was dissolved (1.375 mg per ml). The animals were killed after 16 weeks. The implant area was harvested under sterile conditions and maintained in tissue culture. The cumulative collection of tissue culture supernatants over a three-day period was assayed for Prostaglandin E2 (PGE2) via radioimmunoassay. Specimens from Group 1 produced an average of 106.0 +/- 10.9 ng PGE2 on the right side, and 35.3 +/- 6.0 ng PGE2 on the left side. Specimens from Group 2 produced an average of 31.1 +/- 6.1 ng PGE2 on the right experimental side and 26.0 +/- 5.1 ng PGE2 on the left control side. The ratio of PGE2 values for the right divided by the left side yielded higher values in Group 1, compared to Group 2. Cement polymer particles have been shown to produce a florid foreign body histologic reaction similar to that associated with prosthetic loosening in man. This experiment has demonstrated that the increased PGE2 production by the membrane surrounding particulate cement polymer can be suppressed by the administration of an oral cyclo-oxygenase inhibitor. PGE2 has been previously shown to induce bone resorption in vivo and in vitro. The use of nonsteroidal antiinflammatory drugs may be indicated in retarding the bone loss associated with early prosthetic loosening.

Animals↗

PubMed1991

A comparison of the effects of skin coverage and muscle flap coverage on the early strength of union at the site of osteotomy after devascularization of a segment of canine tibia.

A study was done to compare the effects of coverage with skin and those of coverage with a muscle flap on the early return of strength at the site of an osteotomy after interposition of a devascularized segmental autogenous graft, two centimeters long, from a canine tibia. The bone was fixed with a plate. Thirty-two animals were randomized into two groups, one of which was treated with skin coverage and the other of which was treated with muscle flap coverage. Half of the animals from each group were killed at eight weeks and half, at twelve weeks postoperatively. The tibiae were tested to failure in four-point bending. Failure occurred primarily through the site of the distal osteotomy. Maximum bending load (p = 0.0002) and energy absorbed to failure (p less than 0.02) increased significantly between eight and twelve weeks postoperatively in the group in which a muscle flap had been used for coverage. Bending stiffness was significantly greater at eight weeks in the group in which a muscle flap had been used for coverage than in the group in which skin had been used (p less than 0.03). Maximum bending load was also significantly increased at twelve weeks in the group in which a muscle flap had been used compared with the group in which skin had been used (p less than 0.05).

Animals↗

PubMedDate not supplied

Proximal tibial extension medial rotation osteotomy to correct knee flexion contracture and lateral rotation deformity of tibia after polio.

A proximal tibial extension medial rotation osteotomy was performed on 17 tibias in postpoliomyelitis patients to correct knee flexion contractures simultaneously with the correction of lateral rotation deformity of the tibia through the same osteotomy. Gait improved in 10 patients. Five patients developed recurrence of knee flexion contractures; five more developed greater than 20 degrees genu recurvatum. One patient developed a common peroneal nerve palsy. Because of the high incidence of complications, we recommend that this procedure be abandoned.

Adolescent↗

PubMed1990

[Corrective osteotomy of the head of the tibia in primary and secondary gonarthrosis--a para-articular operation].

The corrective osteotomy at the head of the tibia with degenerative or posttraumatic medial or lateral gonarthrosis and misalignment of the axis is until today a procedure to be recommended prior to a total or partial implantation of an endoprosthesis. The main advantage in comparison with a mono-condylar prosthesis is the removal of the causal damage of the misalignment. Old age and general relative risks are no contraindications to this procedure. The method used most in the operative technique is the correction of valgus deviation at the head of the tibia after osteotomy of the fibula with stabilization with a fixateur externe. On the whole, the risk of the operation is very low, the main complication is the lesion of the nervus peronaeus. With regard to the subjective result from the patients point of view the most important aspect is the relief or disappearance of pain, which is reached in comparison with a partial prosthesis of the knee joint with similar security. About two thirds of the patients are subjectively contempt with the results of the operation within a time of three to five years.

Adult↗

PubMed1991

A precision guide-pin technique for wedge and rotatory osteotomy of the femur and tibia.

Intraoperative guide-pin placement for the performance of wedge-type and rotatory osteotomy of the femur and tibia provides the desired angle of correction from single-leg, weight-bearing roentgenograms. A template is used as a guide for pin placement. The accuracy of this technique was evaluated by comparing the preoperative goal with the correction achieved immediately after surgery and after bone healing one year postoperatively. Forty-seven osteotomies, 37 in the tibia and ten in the femur, were reviewed. Eighty-five percent of the cases were within +/- 3 degrees of the operative goal immediately after surgery, and 81% one year postoperatively. Four osteotomies (9%) were considered failures, two because of technique and two because of errors in postoperative patient activity level. With appropriate preoperative planning, the technique makes accurate osteotomy possible in a standard operating room equipped with a C-arm fluoroscope.

Bone Nails↗

PubMed1991

Architecture of the lower end of the human tibia.

The cancellous bone in the lower end of the human tibia is divisible into 3 broad categories, according to the density and disposition of its lamellae. Parallel fenestrated tubes of cancellous bone arise perpendicular to the inferior articular facet of the tibia and meet the shaft obliquely. They diverge from the neutral axis which inclines posterolaterally from the centre of the inferior articular facet. Horizontal lamellae course the medial malleolus, at right angle to its articular facet. The density of the cancellous bone decreases from the periphery to the neutral axis. Spicules of thin bone can be traced from the attachment of ligaments into cancellous bone lying perpendicular to the articular facets.

Humans↗

PubMed1990

[Arthrodesis of the tarsal tibia for the outcomes in fractures of the collum tali. A review of cases and long-term follow-up].

In the wards of the CTO Hospital in Florence, isolated arthrodeses of the tarsal tibia for ankle fractures, or their effects or complications, have been performed on 29 patients in the past 13 years. Of these 29 patients we were able to personally check up on 23, with a follow-up time ranging from one to thirteen years. The patients we followed-up on had been operated on using the Scaglietti technique or its variations in 15 cases, the Charnley technique in 7 cases, and the fixation according to Ilizarov in one case. We examined the pre-operatory clinical-radiographic conditions and the surgical techniques utilized with all of their advantages, disadvantages, limits, and pre and post-operatory complications. In the follow-up studies, for instance, in addition to the subjectivity of the patient we clinically evaluated the commemorative signs and post-ambulatory adaptation phenomena as a function of the residual degree of equinism and, radiologically, the condition of the arthrodesis and the articulation proximal to the tarsal tibia. Tibio-tarsal arthrodesis, notwithstanding the inconveniences common to all types of arthrodesis, has in essence retained its validity regarding the seriously crippling effects of ankle fractures.

Adult↗

PubMed1990

[Congenital bowing and pseudoarthrosis of the tibia in children].

Congenital pseudarthrosis of the tibia is nearly always the result of a congenital bowing of the tibia when it is unilateral and with an antero-external angle. There is no possible spontaneous consolidation and there may be several associated sequellae (shortening and trophic disorders of the limb). The etiological and therapeutic aspects of the affection are reviewed.

Bone Diseases↗

PubMed1990

Prostaglandin E2 levels in the membrane surrounding bulk and particulate polymethylmethacrylate in the rabbit tibia. A preliminary study.

Fourteen mature New Zealand white female rabbits were allocated into two groups. Group 1 received a bolus doughy Simplex polymethylmethacrylate (PMMA) cement injected into the proximal tibia through a drill hole. Group 2 received an equal volume of particulate PMMA cement powder. The operated but nonimplanted left tibiae served as controls. The animals were killed after four months. The membrane surrounding the implant area was harvested aseptically and grown in tissue culture. The supernatants were assayed for prostaglandin E2 (PGE2) via radioimmunoassay. Bulk cement specimens produced on average 12.39 +/- 4.11 ng PGE2 on the right experimental side and 12.29 +/- 3.56 ng PGE2 on the left control side (not statistically different). Cement powder specimens produced 8.82 +/- 1.64 ng PGE2 on the right experimental side, which was statistically different from 4.21 +/- 0.88 ng PGE2 produced on the left control side. The ratio of PGE2 values for the right divided by the left side and the arithmetic difference between right and left sides were significantly higher in the particle group compared with the bulk group. Small, undigestable cement particles may be phagocytosed by foreign-body giant cells and histiocytes and then extruded into the extracellular compartment, along with substances such as PGE2. PGE2 has been implicated as the biologic mechanism for stimulating the bone lysis associated with prosthetic loosening.

Animals↗

PubMed1990

Deficit (14 cm) of the tibia solved by a double sliding graft using the Ilizarov apparatus.

A 14 cm deficit of the tibia with a soft tissue deficit was resolved using the apparatus of Ilizarov. The apparatus was applied using a double corticotomy of the proximal and distal remainder of the tibia. The fragments were moved until they met each other in the central part of the deficit. Afterwards, a part of the apparatus was changed (the constructions for sliding grafts were replaced with two new circles). This enabled the compression between the "kissed" fragments, and the space between those fragments and distal and proximal tibial adjacent to the remaining joints was filled by the newly formed bone formation.

Adult↗

PubMed1990

Changes in geometrical and biomechanical properties of immature male and female rat tibia.

Tibial geometry and mechanical properties in male and female rapidly growing rats were measured to provide comparative data for spaceflight, exercise, or disease experiments that use immature rats as an animal model. A total of 68 immature Sprague-Dawley rats (43-58 d of age) were divided into 8 groups according to age and sex. Tibial length and middiaphysial cross-sectional data were analyzed, and tibial mechanical properties were obtained via three-point bending tests to failure. Results indicated that tibial geometry and mechanical properties were changed significantly during this 15-d period of rapid growth, with male rats having greater increases than female rats. Both male and female tibial lengths nevertheless increased significantly during this growth period, as did middiaphysical cross-sectional area. Tibial flexural rigidity increased significantly for both sexes during this growth period. The male tibiae changed primarily in structural characteristics, but some material properties also changed with age. In the female rats, however, the major changes in mechanical properties of the tibia were attributable only to structural changes in the bone.

Age Factors↗

PubMedDate not supplied

[Value and technique of measuring the tibia length in pathological conditions of the newborn (author's transl)].

Together with determining the bone age of the immature and/or small-for date neonate, it is possible to work out the length of the tibia on the profile X ray of the leg. Authors have drafted up a scale of growth, featuring the 10 th, 50 th and 90 th percentiles common for boys and girls ranging from 28 to 42 weeks of gestation and they propose this new criterion for the study of pathological neonates, particularly the small-for-date. The method has a second advantage: it is possible to follow the increment of the tibia length by X rays taken at regular intervals and thus to estimate the various factors that can interfere with the child's growth, and in the first place, the quality of the food given to the child.

Female↗

PubMed1990

[Circulatory changes in the rat tibia in dietary calcium and vitamin D deficiency. Effects of age and sex].

In previous experiments (4) we observed in laboratory rats after a low Ca content diet with no vitamin D a decrease of blood flow through bones. In this study we follow whether the effect of the deficit diet is influenced by age or sex of experimental animals. Tibia blood flow in rats is established by 85Sr-microparticles, bone density is estimated by weighing the bone under water. After 10 days of feeding by the deficit diet 85Sr-microparticles catchment in young males is decreased to 74% of that of controls, in young females to 61%, blood flow is decreased to 46% and 51% respectively. In older males after the diet the microparticles catchment is significantly decreased to 63%, blood flow is non-significantly decreased to 82% (as a result of higher cardiac output). In the category of older females the effect of deficient diet is not demonstrable as regards both microparticles catchment and blood flow. Bone density in preliminary experiment after 40 days of diet is significantly decreased in males of both age categories and in young females, in the main experiment after 10 days of diet it is decreased only in the categories of young males and females. From the results obtained in following the effect of diet deficient in Ca and vitamin D on density and local blood flow in tibia of rats can be concluded 1) that in this respect younger rats are more susceptible, 2) in the category of older males the effect is partly demonstrable in males, but not in females.

Age Factors↗