Midfemoral Bone Volume of Walking Subjects with Chronic Hemiparesis Post Stroke.

BACKGROUND AND PURPOSE: Muscle and bone form a functional unit. Residual physical poststroke impairments such as muscle weakness, spasticity, and decrease in function can promote metabolic bone changes. Moreover, muscle strength can influence this process. Thus, the purpose of the present study was to investigate bone volume and mobility performance in subjects with chronic hemiparesis post stroke. METHODS: A cross-sectional study was performed on 14 subjects post stroke who were paired with healthy controls. Bone volume, isometric muscle performance, and mobility levels were measured. Midfemoral bone volumes were determined using magnetic resonance imaging, and muscular performance was measured by dynamometry. Mobility was measured using the Timed Up and Go Test and the 10-Meter Walk Test. RESULTS: Regarding bone volume total, there was no difference in the medullary and cortical groups (P ≥ .05). During torque peak isometric flexion, the paretic group was significantly different compared with the other groups (P = .001). However, the control presented no difference compared with the nonparetic limb (P = .40). With regard to the extension isometric torque peak, the paretic limb was significantly different compared with the nonparetic (P = .033) and the control (P = .001) limbs, and the control was different from the nonparetic limb (P = .045). Bone volume variables correlated with the isometric torque peak. CONCLUSIONS: Chronic hemiparetic subjects maintain bone geometry compared with healthy volunteers matched by age, body mass index, and gender. The correlation between bone volume midfemoral structures and knee isometric torque was possible.

Avaliação da disponibilidade óssea para enxertos, na região de calota craniana, por meio da tomografia computadorizada de feixe cônico / Evaluation of available bone for grafting in the cranial bone region by means of cone beam computed tomography

A reabsorção óssea dos processos alveolares da maxila e mandíbula, após exodontias, é um grande problema para sua reabilitação estético-funcional. Entre as opções de tratamento, os enxertos ósseos são realizados com o objetivo de resolver esta carência de osso, e a escolha das possíveis áreas doadoras de osso para este tipo de reconstrução depende, principalmente, do volume de osso que se necessita e do tipo de defeito ósseo a ser corrigido, podendo ser proveniente de áreas doadoras intrabucais ou extrabucais. Quando a quantidade necessária de osso é pequena, pode-se utilizar áreas doadoras intrabucais. Para reconstruções maiores, as áreas doadoras extrabucais, como a crista do ilíaco, calota craniana, tíbia, fíbula e costelas são os locais de escolha. Entretanto, o volume de osso disponível nas diferentes áreas doadoras ainda é avaliado de forma empírica. Neste estudo foi considerada uma região correspondente à área doadora de formato hexagonal medindo 8cm de comprimento e 6cm de largura e logo em seguida foi calculado a área desse hexágono. Foram também realizadas medidas da espessura de osso cortical, osso medular e osso total, em 9 regiões da calota craniana, em 50 tomografias computadorizadas de feixe cônico (TCFC). Essas medidas foram realizadas com a ferramenta distância do software i-CAT Vision®, utilizado para a visualização dos exames em reformatações sagitais e coronais. O resultado da área do hexágono correspondente a área doadora multiplicado pela média de espessura dos 9 pontos da calota craniana foi de 2.499mm³.(AU)

The bone resorption of the alveolar processes of the maxilla and mandible, after exodontia, is a great problem for its aesthetic-functional rehabilitation. Among the treatment options, bone grafts are performed with the aim of solving this bone deficiency, and the choice of possible bone donor areas for this type of reconstruction depends, mainly, of the volume of bone required and the type of osseous defect to be corrected, which may be from intraoral or extraoral donor areas. When the required amount of bone is small, intraoral donor areas may be used. For larger reconstructions, extraoral donor areas, such as iliac crest, skull cap, tibia, fibula, and ribs are the sites of choice. However, the volume of bone available in the different donor areas is still evaluated empirically. In this study was considered a region corresponding to donor area of hexagonal shape measuring 8cm in lenght and 6cm in widht and then calculated the area of this hexagono. In this study, measurements of the thickness of cortical bone, medullary bone and total bone were performed in 9 regions of the skull cap in 50 conical beam computed tomography (CBCT) scans. These measurements were performed with the distance tool of the i-CAT Vision® software, used to visualize the exams in sagittal and coronal reformations. The result of hexagon area corresponding to donor area multiplies by average of the thickness of 9 points of skull cap was 2.499mm³.(AU)

Validação de dois métodos de análise volumétrica e linear óssea em tomografia computadorizada multislice 3D / Validation of two methods of volumetric and linear bone analysis in 3D multislice computed tomography

O objetivo deste trabalho foi avaliar a acurácia e reprodutibilidade de medidas ósseas lineares e volumétricas através do processamento de dados obtidos por tomografia computadorizada multislice por dois softwares Amira6® e CoDiagnostiX®. O material da pesquisa foi composto de uma mandíbula seca. Foi feita uma tomada tomográfica da peça intacta e uma segunda tomada com a mandíbula adicionada de quatro enxertos em bloco de diferentes dimensões, além de quatro desgastes. Os dados obtidos foram então processados através dos dois softwares por 3 examinadores, previamente calibrados, duas vezes cada um. As medidas físicas lineares dos blocos foram obtidas com um paquímetro digital e as de volume dos blocos e desgastes pela técnica do deslocamento em água em um cilíndro milimetrado. O volume dos desgastes foi obtido por preenchimento dos mesmos com resina bisacrílica de uma moldagem feita com a mandíbula intacta sobreposta na mesma com os desgastes, estes dados foram processados apenas pelo software Amira6® que permite a sobreposição de imagens 3D. A acurácia das medidas lineares e de volume foi avaliada pela comparação com o padrão ouro através do teste-T de Student e ANOVA. Os resultados mostraram que não houve diferença estatística significante nas medidas lineares e volumétricas obtidas entre os dois softwares e quando comparados individualmente com o padrão ouro.

The aim of this study was to evaluate the accuracy and reproducibility of linear and volumetric bone measurements through data processing obtained by multislice computed tomography for two softwares: Amira6® and CoDiagnostiX®. The research material was composed of a dry mandible. A first tomography was made and then the jaw was added with four bone block grafts of different sizes and four wears were made in the chin area. The data were then processed twice using the two softwares by 3 examiners previously calibrated. Linear physical measurements of the blocks were obtained with a digital caliper and the volume of the blocks and wears by water displacement in a calibrated cylinder. The volume of each wear was obtained by filling the same with bis-acrylic composite of a matrix made with the jaw intact superimposed on it, these data were processed only by Amira6® software that allows 3D images overlap. The accuracy of linear and volumetric measurements was evaluated by comparison to the gold standard by Student T-test and ANOVA. The results showed no statistically significant difference in linear and volumetric measurements between the two softwares and individually when compared with the gold standard.

Fresh-frozen allografts combined with bovine bone mineral enhance bone formation in sinus augmentation.

We evaluated histologically, histomorphometrically, and tomographically the effects of the association of fresh-frozen bone allograft (FFB) with bovine bone mineral (BBM) in maxillary sinus floor augmentation. In total, 34 maxillary sinuses from 29 patients, with a mean age of 51.32 (±6.44) years, underwent sinus augmentation. Patients were divided into control and test groups (17 sinuses each). The controls were grafted with allograft bone, and the test group received a combination of FFB and BBM at a 2:1 ratio. After 6 months, bone samples were collected for histological and histomorphometric examinations. The implant survival rates were 93.02% (control group) and 100% (test group) at 6 months after functional loading. Median volumetric reductions of 28.32% (17.05-44.05) and 12.62% (5.65-16.87) were observed for the control and test groups, respectively. Statistically significant histomorphometric differences were found between the control and test groups regarding newly formed bone 12.54% (10.50-13.33) vs. 24.42% (17.62-35.92), p < 0.001, total bone 48.34% (39.03-54.42) vs. 61.32% (50.61-64.96), p = 0.007, and connective tissue 51.66% (45.57-60.97) vs. 39.30% (35.03-49.37), p = 0.007. The addition of BBM to allograft bone in maxillary sinus augmentation resulted in higher percentages of new bone formation and total bone, and permitted implant placement with a low rate of osseointegration failure at the 6-month follow-up.

How do different sporting activities affect bone patella volume? a descriptive pilot study / ¿Como afectan las diferentes actividades deportivas el volumen de la patela? un estudio piloto descriptivo

The aim of this study was to compare the patella bone volume of sedentary men with that of elite male sportspeople, including judoka, cyclists, weightlifters, and taekwondo athletes who were members of Turkish National Professional Teams. All subjects had no history or clinical signs of an orthopaedic disorder such as osteoarthritis or acromegaly. The right and left knees of all groups were placed side by side in a supine position and were scanned by high resolution imaging with multidetector computed tomography. The differences between the volume of right and left patellae of sedentary men, judoka, cyclists, weightlifters, and taekwondo athletes were statistically significant. The average left patella of a professional cyclist and the average right patella volume of a sedentary man were maximum and minimum, respectively. The results demonstrated that the patella volume of cyclists was significantly larger. According to the literature, patella bone volume was associated with a reduced rate of annual patella cartilage volume loss, so cycling early in life may prevent patella cartilage loss in the future.

El objetivo de este estudio fue comparar el volumen de la patela en hombres sedentarios con la patela de deportistas de elite, incluyendo judokas, ciclistas, levantadores de pesas y atletas de taekwondo, miembros de equipos profesionales nacionales turcos. Los sujetos del estudio no tenían antecedentes o signos clínicos de una enfermedad ortopédica como la osteoartritis. Las rodillas derecha e izquierda de los individuos de todos los grupos se colocaron una al lado de otra, en posición supina y fueron escaneadas por tomografía computarizada multidetector de alta resolución. Las diferencias entre el volumen de la patela derecha e izquierda de los hombres sedentarios, atletas judokas, ciclistas, levantadores de pesas y atletas de taekwondo fueron estadísticamente significativas. El volumen promedio de la patela izquierda de un ciclista profesional y el volumen promedio de la patela derecha de un hombre sedentario fueron de máximo y mínimo, respectivamente. Los resultados demostraron que el volumen de la patela de ciclistas fue significativamente mayor. De acuerdo a la literatura, el volumen del hueso de la patela fue asociado con una pérdida anual de volumen del cartílago, razón por la cual el ciclismo en una edad temprana puede prevenir la pérdida de cartílago de la patela en el futuro.

Impairment of rat tooth eruption in pups born to mothers exposed to chronic stress during pregnancy.

OBJECTIVE: Tooth eruption is a multifactorial process in which bone tissue plays a prevailing role. In this study we evaluated the bone overlying the developing tooth germ and the degree of tooth eruption of the first mandibular molar in pups born to mothers subjected to constant light during pregnancy. DESIGN: Pregnant rats were divided into two groups: mothers chronically exposed to a 12:12 light/light cycle (LL) from day 10 to 20 of pregnancy and controls (C) maintained on a 12:12 h light/dark cycle. Pups from each group were euthanized at the age 3 or 15 days. Buccolingually oriented sections of mandibles were stained with haematoxylin-eosin or for histochemical detection of tartrate resistant acid phosphatase (TRAP). The histomorphometric parameters evaluated were bone volume, number of osteoclasts, TRAP+ bone surface, number of TRAP+ and TRAP- osteoclasts per mm(2) and degree of tooth eruption (mm). RESULTS: It was found an increase in bone volume (LL: 58.14±4.24 vs. C: 32.31±2.16; p<0.01) and a decrease in the number of osteoclasts (LL: 3.5±0.65 vs. C: 8.03±1.31; p<0.01) and TRAP+ cells (LL: 0.84±0.53 vs. C: 8.59±1.26; p<0.01) in 3-day-old pups born to LL-exposed mothers. These observations are consistent with the decrease in the degree of tooth eruption observed in 15-day-old experimental pups (LL: -0.605±0.05 vs. C: -0.342±0.02; p<0.0001). CONCLUSION: Our results suggest that chronic constant light applied as a pre-natal stressor impairs the resorptive capacity of osteoclasts involved in the formation of the eruption pathway and consequently the degree of tooth eruption.