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PubMed1986

A case of multicentric synchronous osteosarcoma treated with a vascularized tibia graft from an amputated limb.

A 10-year-old girl with synchronous lesions of osteosarcoma in the left proximal tibia and in the right distal radius but with no lung metastasis was treated by an innovative procedure. After an above-knee amputation and a wide excision of the distal halves of the radius and ulna, the skeletal defect of the forearm was replaced by the distal tibia harvested from the amputated leg using the microsurgical technique of revascularization. The result was encouraging up to the point of her death due to other, widespread lesions.

Amputation, Surgical↗

PubMed1986

Bone strength measurements at the proximal tibia. Penetration tests and epiphyseal compressive strength.

Three penetration tests were obtained from corresponding locations at each condyle of 19 proximal tibiae. The patterns of condylar cancellous bone strength varied little between knees. The medial condyle was the strongest with an average medial to lateral strength ratio of 1.9, and in most knees the medial condyle was strongest centrally while the lateral condyle was strongest posteriorly. The penetration strength at 5 successive 2 mm levels beneath the resected subchondral surface also showed a constant pattern of variation. Bone strength decreased significantly at first except at the posterolateral site, then tended to level off. The reduction of strength was most pronounced in the centre of the condyles. The penetration tests were good predictors of the static compressive strength of the proximal tibia. Correlation coefficients of approximately 0.90 were obtained indicating statistically highly significant correlations (p less than or equal to 0.00001). The tests were carried out with equipment developed for in vivo measurements of cancellous bone strength during total knee replacement. The findings confirm the close relationship of these investigations to conventional compression tests.

Aged↗

PubMed1993

Micromelic dwarfism--humerus, femur, tibia type. Report of a case.

A 12.5-year-old girl with severe micromelic dwarfism and characteristic radiographic findings is reported. The most important phenotypic abnormality was dwarfism (stature < 100 cm); the patient had a normal face and intelligence. The diagnostic radiographic findings were those of spondylo-epimetaphyseal dysplasia characterized by severe shortening of humerus, femur and tibia, hypoplastic but normal-shaped fibula, ulna and radius, uniform shortening of the short tubular bones and moderately severe platyspondyly. These radiographic changes were already present at birth, which should make it possible to recognize the disease in the newborn. We propose naming this disorder micromelic dwarfism-humerus, femur, tibia type.

Child↗

PubMed2000

Characterisation of three-dimensional anatomic shapes using principal components: application to the proximal tibia.

The objective of the research is to determine if principal component analysis (PCA) provides an efficient method to characterise the normative shape of the proximal tibia. Bone surface data, converted to analytical surface descriptions, are aligned, and an auto-associative memory matrix is generated. A limited subset of the matrix principal components is used to reconstruct the bone surfaces, and the reconstruction error is assessed. Surface reconstructions based on just six (of 1452) principal components have a mean root-mean-square (RMS) reconstruction error of 1.05% of the mean maximum radial distance at the tibial plateau. Surface reconstruction of bones not included in the auto-associative memory matrix have a mean RMS error of 2.90%. The first principal component represents the average shape of the sample population. Addition of subsequent principal components represents the shape variations most prevalent in the sample and can be visualised in a geometrically meaningful manner. PCA offers an efficient method to characterise the normative shape of the proximal tibia with a high degree of dimensionality reduction.

Adult↗

PubMed1981

Bone loss in the beagle tibia: influence of age, weight, and sex.

In a cross-sectional study, 154 Beagles (79 males, 74 females) ranging in age from 14 to 187 months were measured for bone mineral, bone width, and mineral-to-width ratio on the distal shaft of the right tibia using a photon absorptiometer. The measurements were evaluated with regard to age, sex and body weight. The results indicate that males were heavier than females in body weight, with weight being reduced in the older animals of both sexes. When compared on an age basis, males had more mineral, a wider tibia, and a greater mineral-to-width ratio than females. The males and females reach their peak mineral, and mineral-to-width ratio at about 6 years of age and then decline. On a body weight basis, mineral, width and mineral-to-width ratio all increase with increasing body weight, with bone width being the least affected by changes in body weight. The values for females are less than those for males in all parameters with the greatest differences occurring at the greater weights. The only variance from these observations was the greater mineral-to-width ratio in the lighter females. It is concluded that, when examining cortical bone, the Beagle is a model of age-related osteopenia, and body weight is an important consideration when explaining changes in bone mineral.

Aging↗

PubMed1975

Effects of ethanol on chicks in vivo and on chick embryo tibiae in organ culture.

Hypocalcemia previously reported in rats and dogs following oral administration of ethanol may have been caused by a movement of calcium from blood to bone. This present study was undertaken to determine whether ethanol also causes hypocalcemia in chicks and to investigate the direct effects of ethanol on mineral accretion, glucose metabolism and growth of embryonic chick tibiae in an organ culture system. A high dose of ethanol (6 g/kg body wt) produced hypocalcemia, hypermagnesemia and an elevated hematocrit in chicks. Results in vitro were as follows: 1) 5 to 30 mul ethanol/ml medium produced dose-related increases in bone mineral from 58-440%; 2) lactate production was inhibited at all ethanol levels; 3) increased mineral accretion did not occur in ethanol-treated tibiae when iodoacetate was in the medium, but did occur in mechanically disrupted bones exposed to ethanol; and 4) the ethanol response in bone was directly related to the medium phosphate concentration. The results lead to the following conclusions: 1) ethanol has a direct stimulatory effect on bone mineral accretion and an inhibitory effect on bone glucose metabolism in vitro; 2) viable bone cells and an adequate phosphate supply are necessary for the ethanol response, but tissue integrity is not; and 3) the hypocalcemic effect of ethanol in vivo may at least partially result from ethanol-stimulated bone mineral deposition.

Animals↗

PubMed1991

Immunohistochemical localization of a approximately 66 kD glycosylated phosphoprotein during development of the embryonic chick tibia.

Localization of a approximately 66 kD glycosylated phosphoprotein during morphogenesis of the embryonic chick tibia has been accomplished using immunohistochemistry. Although initial expression of the tibial osteoblast phenotype is detected as early as stage 28.5, with the deposition of osteoid matrix beginning at stage 30, little or no immunoreactivity against the approximately 66 kD glycosylated phosphoprotein is observed in pre-osteoblasts, osteoblasts, osteocytes, or in the uncalcified osteoid matrix during the early events of tibia development. Immunoreactivity was first observed at stage 32 when mineralization of the osteoid matrix is initiated. At this and all later stages, the phosphoprotein is located almost exclusively in the extracellular matrix at the mineralization front with essentially no detectable staining in the adjacent unmineralized osteoid matrix. Similarly, no cellular staining is observed when even the lightly mineralized extracellular matrix is strongly immunoreactive. Only scant immunostaining is present over the heavily mineralized regions, although demineralization of these areas with EDTA exposes a low intensity, punctate staining pattern. Additionally, cryosections of developing calvaria stained with this antiserum only display reactivity in regions of bone matrix undergoing mineralization. These localization studies support the hypothesis that this phosphoprotein is intimately associated with the process of bone matrix mineralization in the developing chick long bone.

Animals↗

PubMed1989

Microdamage in response to repetitive torsional loading in the rat tibia.

Tibiae from 60 male Wistar rats, aged 13 +/- 1 weeks, were divided into six groups for mechanical and histological testing. Bones were loaded repetitively in torsion at 90 deg.s-1. Group 1 was subjected to 5,000 loading cycles at a twist angle of 3.6 degrees, groups 2-5 to 10,000 cycles at 3.6, 5.4, 7.2, and 9.0 degrees, respectively, and group 6 was tested to failure. Six transverse sections from the middiaphysis were then cut, bulk-stained in basic fuchsin, and hand ground to 30-50 microns to examine the presence of microcracks. Cracks were classified as running parallel to lamellae, crossing lamellae, crossing the full thickness of the cortex, or invading vascular canals. Results for fatigue testing showed that the tibiae exhibited a gradual decrease in torque (P less than 0.05), average stress (P less than 0.01), stiffness (P less than 0.01) and energy absorbed (P less than 0.01) from the initial loading cycle. Analysis of microdamage showed an increase in the variety of cracks from groups 1-5. Analysis of deviance demonstrated a strong dependence of crack probability on the level of loading for all crack types (P less than 0.05) except those crossing lamellae. This study reinforces the evidence that yielding of bone observed during repetitive loading is caused by diffuse structural damage such as microcracking or debonding.

Animals↗

PubMed2001

[Correction of the leg axis after epiphyseal fracture and progressive abnormal growth of the proximal tibia].

Development of an angular deformity around the knee joint, following a posttraumatic premature epiphyseal closure is a rare but serious complication. We present a case report of this complication following a proximal tibial epiphyseal injury in a 9 year old child initially treated conservatively with plaster immobilization. Subsequently, partial closure of epiphysis on medial side resulted in genu varum of 20 degrees, which was treated with medial open wedge osteotomy of the proximal tibia combined with resection of a segment from the proximal fibula, and a percutaneous epiphysiodesis of the proximal tibia and fibula. At three years follow up, the child had shortening of the leg by 1 cm, but no angular deformity. Significance of regular follow-up after an epiphyseal injury to detect the condition and role of operative management with various modalities is discussed.

Casts, Surgical↗

PubMed2005

[Frequency and severity of callus defects. Dorsomedial vs ventrolateral approach for corticotomy in performing callus distraction of the tibia].

BACKGROUND: The purpose of this study was to compare a dorsomedial to the ventrolateral approach for corticotomy in performing callus distraction of the proximal metaphyseal tibia. PATIENTS AND METHODS: A total of 31 callus distractions were performed in 28 humans. The ventrolateral approach was used for 18 and the dorsomedial approach for 13 corticotomies. A scale of four severity grades was used to classify callus defect zones based on their extent as evidenced on serial X-rays. Biopsies were taken from higher-grade defects (grades 3-4). RESULTS: A total of 13 radiological evaluations revealed 12 defects using the ventrolateral approach. Seven defects (grades 1-2) healed spontaneously, whereas six defects (grades 3-4) required operative intervention as histological tissue examination showed no osteogenic potential. CONCLUSION: To prevent callus defects of the proximal tibia in the future and to ensure maximal osteogenic potential in the distraction zone, a minimally invasive dorsomedial approach appears to achieve favorable results.

Adolescent↗

PubMed1999

Quantitative ultrasound measurements of the tibia and calcaneus in comparison with DXA measurements at various skeletal sites.

The performance of quantitative ultrasound (QUS) measurements of the tibia and calcaneus was studied in 109 elderly people (age range 65-87 years). Broadband ultrasound attenuation (BUA) and speed of sound (SOS) were measured at the calcaneus and SOS was assessed at the tibia. Short-term precision of tibial QUS was studied in 16 volunteers. The coefficient of variation (CV) was 0.4% and the standardized CV (sCV) was 4.4%. We compared the calcaneal and tibial QUS measurements with bone mineral density (BMD) measurements of the lumbar spine, femoral neck, trochanter and total body assessed by dual-energy X-ray absorptiometry (DXA). Calcaneal QUS correlated better with BMD at various skeletal sites than tibial QUS. Calcaneal BUA showed higher correlations with BMD values of the lumbar spine, femoral neck, trochanter and total body than calcaneal and tibial SOS (r = 0.48-0.64, r = 0.30-0.47, r = 0.35-0.47, respectively; p < 0.001). Body weight modified the relationships between calcaneal and tibial QUS and BMD measurements of the hip. Higher body weight was associated with higher BMD values at the femoral neck and trochanter for the same calcaneal and tibial QUS values. After adjustments for body weight correlations of tibial and calcaneal QUS with BMD improved and were very similar. This suggests that correction for body weight is important and could add to the predictive value of QUS measurements.

Aged↗

PubMed2001

Quantitative ultrasound of the tibia depends on both cortical density and thickness.

This study investigated whether tibial speed of sound (SOS; SoundScan 2000, Myriad Ultrasound Systems, Israel) reflects not only bone mineral density (BMD) but also tibial cortical thickness, as assessed by dual-energy X-ray absorptiometry (DXA) and Quantitative CT (QCT) at a site-matched location. The secondary focus of the study was how tibial SOS compares with BMD at the spine and the hip, the most widely used locations for densitometry. Twenty-two young normal (N) and 23 postmenopausal women with spinal fractures (Fx) (mean (SD) age 35 (8) and 70 (5) years) underwent quantitative ultrasound (QUS) SOS measurement at the left tibial midshaft. From site-matched QCT scans (three 3-mm slices spaced along the QUS measurement region), BMD and cortical thickness were computed (QCT-cBMD, QCT-cTh). The cortex in the CT images was then subdivided into three concentric and equally spaced bands, and QCT-cBMD was computed separately for each band. DXA was performed at the mid-tibia (TIB BMD), at the spine (SPINE BMD) and the hip (total hip, HIP BMD). Correlation coefficients between parameters were determined with least-square linear fits. Intergroup differences were assessed by analysis of covariance, whose r2 value reflects the percentage variation in the data explained by group assignment. SOS correlated significantly with site-matched parameters (QCT-cBMD, OCT-cTh and TIB BMD, all r = 0.6, p < 0.001), SPINE BMD and HIP BMD (both r = 0.5, p < 0.001). Multiple regression with both QCT-cBMD and QCT-cTh against SOS yielded r = 0.7 with both parameters contributing significantly. For the cortex band subdivision, SOS correlated better with QCT-cBMD in the outermost band of the cortex (r = 0.67) than with the more central bands (r = 0.59 and r = 0.53). Group assignment could best explain SPINE BMD (r2 = 0.62) and HIP BMD (r2 = 0.51). SOS was comparable to TIB BMD (r2 = 0.3 vs. r2 = 0.35).: Our findings suggest that the tibial SOS measurement depends on both the thickness and density of the tibia, but is more strongly influenced by the density of the cortex near the surface than by its interior parts. The power of tibial ultrasound to discriminate between normal and fracture patients was less than that of spinal and femoral DXA BMD and comparable to site-matched DXA BMD.

Absorptiometry, Photon↗

PubMed2004

Growth of C57BL/6 mice and the material and mechanical properties of cortical bone from the tibia.

Murine models are becoming increasingly important for studying skeletal growth and regulation because of the relative ease with which their genomes can be manipulated. This study measured the changes in cortical bone of tibiae from one of the more common models, the C57Bl/6, as a function of aging. A total of 97 mice, male and female, were studied at the ages of 1, 2, 3, 6, 9, and 12 months. The body weight of the animals, the length of the tibiae, the composition (in terms of mineral and organic mass fractions), and the density and modulus of the bone were measured. Peripheral quantitative computed tomography was also used to measure bone mineral density (BMD), total and cortical areas, and the cross-sectional moment of inertia. Most parameters measured followed a growth-like curve, which leveled off some time before 6 months of age. Bone composition and modulus were the same at maturity in both sexes, but there were sex-related differences in the modulus with aging. Dimensional measurements and the density of the bone showed significant differences between male and female animals at all ages, with the male mice having larger values. Skeletal maturity for most factors in C57Bl/6 mice has been reached before the age of 6 months.

Aging↗

PubMed2006

Disruption of four-and-a-half LIM 2 decreases bone mineral content and bone mineral density in femur and tibia bones of female mice.

Four-and-a-half LIM 2 (FHL2) is a member of a family of LIM domain proteins which mediate protein-protein interactions. FHL2 acts as a coactivator and binds to important regulators of bone formation such as insulin-like growth factor binding protein (IGFBP)-5, androgen receptor, and beta-catenin. We hypothesized that FHL2 is an important regulator of bone formation. We evaluated growth and skeletal parameters in FHL2 knockout (KO) and wild-type (WT) mice at 4, 8, and 12 weeks of age. At 4 weeks of age, lack of FHL2 reduced femur, tibia, and total bone mineral content (BMC) and body weight in all mice. A gender-by-treatment interaction (P <or= 0.05) was observed for several parameters due to a greater reduction in females. Specifically, femur BMC was reduced 11-27% at 8 and 12 weeks of age and BMD was reduced 7-13% at all ages in female KO mice (P < 0.05). A similar reduction was observed in the tibias at 8 weeks of age. A 6% reduction (P = 0.07) in femur cortical thickness was observed at 12 weeks of age in female KO mice. Interestingly, a gender-specific reduction in IGFBP-5 expression was observed in the femurs of female KO mice. During differentiation of bone marrow stromal cells into osteoblasts, expression of osteocalcin, alkaline phosphatase, and bone sialoprotein was reduced 47-96% in FHL2 KO cells (P < 0.001). In conclusion, FHL2 is an important regulator of peak bone mass, lack of FHL2 produces gender- and site-specific effects on bone accretion and IGFBP-5 expression, and FHL2 is important for optimal osteoblast differentiation in vitro.

Animals↗

PubMed1996

Leukemia inhibitory factor produces hypercalcemia in rats without altering bone histomorphometry of the tibia.

Leukemia inhibitory factor (LIF) is a single-chain polypeptide that previously was shown in mice to produce hypercalcemia and influence skeletal growth and turnover. We performed dose-response studies to determine if LIF alters the serum calcium or histomorphometry of the tibia in growing male rats. Forty animals were divided into five groups of eight animals each. Recombinant human LIF, 0.01, 0.1, 1, or 10 microg/100 g body wt, or vehicle was administered daily S.C. for 3 weeks. Compared with controls it was found that LIF increased mean serum calcium at the two highest doses (11.4 +/- 0.1 versus 10. 8 +/- 0.1 mg/dl, P = 0.0005 by one-way analysis of variance (ANOVA) but did not alter static or dynamic measurements of histomorphometry or length of the tibia. We conclude that in growing rats, high systemic concentrations of LIF result in hypercalcemia with no changes in bone turnover.

Animals↗

PubMed1996

The relation between trabecular bone strength and bone mineral density assessed by dual photon and dual energy X-ray absorptiometry in the proximal tibia.

The feasibility of two noninvasive methods [dual photon absorptiometry (DPA) and dual energy X-ray absorptiometry (DXA)] for prediction in vivo of local variations of trabecular bone strength within the proximal tibia was evaluated in 14 cadaveric knees. Trabecular bone strength was measured using an osteopenetrometer and from destructive compression tests performed on bone cylinders, thus measuring the penetration strength and ultimate strength in the medial, lateral, and central part of the tibial bone specimens. Linear regression analysis showed significant relations between BMD measured by DPA (r2 = 72%) or DXA (r2 = 73%) and ultimate strength. Even closer relations between BMD (DPA: r2 = 80%, DXA r2 = 81%) and penetration strength of trabecular bone were found. We conclude that DPA and DXA are suitable methods for evaluation in vivo of local variations in trabecular bone strength within the proximal tibia, and could easily be performed preoperatively before insertion of total knee arthroplasty.

Adult↗

PubMed2003

An unusual form of congenital anterolateral tibial angulation-the delta tibia.

We report three infants with a poorly known form of congenital anterolateral angulation of the tibia with distinctive features seen on lateral roentgenograms. In these films the affected tibia appears to be divided into two segments, one proximal and the other distal, which taper as they approach each other at the site of the angulation, and end separately at the apex of the curve with an intervening radiolucent gap in the anterior tibial cortex. The two tibial segments are originally bridged and held firmly in that position by a well-defined triangular osseous structure located in the concavity of the tibial bow. It appears from the three cases reported in this paper and a few comparable cases in the literature that this form of tibial bowing is not prone to fracture followed by pseudoarthrosis and that it tends to improve (and resolve) spontaneously, with a resorption of the intramedullary bony structures at the apex of the curve resulting in the formation of a normal medullary cavity. A limb length discrepancy of varying degree is the main residual change of the anomaly.

Humans↗

PubMed2002

Osteoblastoma-like osteosarcoma of the distal tibia.

We report a case of a 14-year-old boy with an intracompartmental lytic lesion with poorly defined margins in the right distal tibia that was originally treated with curettage and bone grafting. Histologic examination showed an osteoblastic tumor with unusual features, which was found on consultation to be an osteoblastoma-like osteosarcoma, a rare, low-grade variant of osteosarcoma. Subsequently, the patient underwent en bloc resection of the distal tibia, which was replaced with vascularized bone graft and followed by chemotherapy. Two years later, he is alive with lung metastases.

Adolescent↗