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PubMed1997

Morphological and dimensional changes after barrier removal in bone formed beyond the skeletal borders at titanium implants. A kinetic study in the rabbit tibia.

The aim of the present experimental investigation was to study the morphological and dimensional changes of bone, augmented at titanium implants by a membrane technique, taking place after membrane removal. In 12 rabbits, screw-shaped titanium implants were inserted in the tibial metaphyses in such a way that 5 threads became uncovered with bone. Surgery was performed on 2 occasions in order to retrieve specimens with different follow-up times. An e-PTFE barrier and a titanium device were used to provide space for bone formation. In 1 tibia of each rabbit, the membranes and spacers were removed after 8 weeks of healing, and the implants followed for 16 more weeks. Impressions were taken at day 0 and after 8 and 24 weeks of healing and plaster models were produced. In the contralateral tibiae, implants were inserted either 16 or 8 weeks prior to sacrifice. Measurements were made on the plaster models in 3 dimensions at 35 points around each implant in a coordinate measuring machine. Specimens taken 8, 16 and 24 weeks after insertion were analysed by means of light microscopical morphometry. The coordinate measurements showed that, in mean, 1.92 mm of bone had been formed during the first 8 weeks. A statistically significant loss of the height of the newly formed bone (0.70 mm) and thereby reduction of bone volume was found 24 weeks postoperatively. The volume decrease of the newly formed bone was more pronounced beside the implants than over the implant body. The histology showed that woven bone had been formed at the implants after 8 weeks. Further bone formation and remodelling and a net increase of mineralized bone were seen. The degree of bone-implant contact and bone area in the threads increased with time. The present study showed that coordinate measurements on plaster models, obtained from the experimental areas, in combination with histology, form a useful technique to study long-term changes of augmented bone. It was found that bone formed by a barrier membrane technique, decreased in volume during a 16-week follow-up period after barrier removal. Less dimensional changes were observed for the bone formed over the implant body, indicating that a solid surface may have a stabilizing effect on the augmented bone.

Animals↗

PubMed2001

Effects of chair restraint on the strength of the tibia in rhesus monkeys.

To determine the effects of the relative inactivity and unloading on the strength of the tibias of monkeys, Macaca mulatta, we used a non-invasive test to measure bending stiffness, or EI (Nm2), a mechanical property. The technique was validated by comparisons of in vivo measurements with standard measures of EI in the same bones post-mortem (r2 = 0.95, P < 0.0001). Inter-test precision was 4.28+/-1.4%. Normative data in 24 monkeys, 3.0+/-0.7 years and 3.6+/-0.6 kg, revealed EI to be 16% higher in the right than left tibia (4.4+/-1.6 vs. 3.7+/-1.6 Nm2, P < 0.05). Five monkeys, restrained in chairs for 14 days, showed decreases in EI. There were no changes in EI in two chaired monkeys that lost weight during a 2-week space flight. The factors that account for both the decreases in bone mechanical properties after chair restraint at 1 g and lack of change after microgravity remain to be identified. Metabolic factors associated with body weight changes are suggested by our results.

Adaptation, Physiological↗

PubMed2003

Loss of bone mineral of the hip and proximal tibia following rupture of the Achilles tendon.

In a prospective uncontrolled study 12 patients suffering from a rupture of the Achilles tendon treated operatively with surgical repair and post-operative immobilization in a short plaster cast for 6 weeks had bilateral measurements of bone mineral content (BMC) of the proximal tibia and bone mineral density (BMD) of the femoral neck and greater trochanter. The measurements were performed by dual energy X-ray absorptiometry (DEXA) and scans were performed post-operatively within 7 days after the operation and with follow up after 6 weeks, 3, 6, and 12 months. In the operated legs, BMC of the proximal tibia showed a progressive decrease reaching a total bone loss of 6.4% (95%-CL: -10.6%; -2.3%) 1 year after the injury. Bone mineral density at the hip of the operated legs also decreased significantly and 1 year after the injury BMD was 2.5% (95%-CL: -5.5%; 0.5%) and 6.8% (95%-CL: -9.8%; -3.7%) below the initial value in, respectively, the femoral neck and greater trochanter. Patients with a previous Achilles tendon rupture must be considered to be some years ahead in their natural osteoporotic process of the bones of the affected legs, and an increased risk of osteoporotic fractures must be considered not to be only theoretical.

Absorptiometry, Photon↗

PubMed1994

A hominid tibia from Middle Pleistocene sediments at Boxgrove, UK.

Fossil hominids from the earlier Middle Pleistocene of Europe are very rare and the Mauer mandible is generally accepted as the most ancient, with an estimated age of 500 kyr. We report here on the discovery of a human tibia, in association with stone tools, from calcareous silts at the Lower Palaeolithic site of Boxgrove, West Sussex, UK (Fig. 1). The silt units are correlated by mammalian biostratigraphy to an, as yet unnamed, major temperate stage or interglacial that immediately pre-dates the Anglian cold stage. Accordingly, the temperate sediments are equated with oxygen isotope stage 13 (ref. 6) and are therefore roughly coeval with the Mauer mandible. The massive tibia is the oldest hominid fragment from the British Isles and provides the first information about the manufacturers of the early Acheulian industries of Europe. It is assigned to Homo cf. heidelbergensis.

Animals↗

PubMed2000

Effect of ovariectomy on bone remodeling adjacent to hydroxyapatite-coated implants in the tibia of mature rats.

PURPOSE: The purpose of this study was to examine the effects of estrogen deficiency on bone remodeling adjacent to implants in the tibia of mature rats. MATERIALS AND METHODS: Hydroxyapatite-coated implants were placed bilaterally in the proximal metaphysis of the tibia of 18 female Wistar rats (48 weeks old), and ovariectomy was performed 168 days later. As a control, sham ovariectomy was performed in a similar group of 18 rats. Six animals from each group were killed at 28, 84, and 168 days after ovariectomy. Undecalcified sections were prepared, and changes in the bone tissue around the implants were evaluated histologically. Histomorphometric measurements were made with a computer-based image analyzer to quantify the unit bone mass around each implant and the amount of implant-bone contact. RESULTS: In the cortical bone area, ovariectomy induced only a slight decrease in bone contact with the implant, compared with that in the sham-operated rats. However, both the bone volume around the implant and implant-bone contact were significantly decreased in the cancellous bone area in ovariectomized rats compared with the sham-operated rats. CONCLUSION: Thinning of the bone trabeculae holding dental implants may occur with estrogen deficiency.

Animals↗

PubMed2002

Anthropometry of the proximal tibia to design a total knee prosthesis for the Japanese population.

Anthropometric data on proximal tibiae of 100 knees in 80 Japanese patients undergoing total knee arthroplasty were obtained. Anterior-posterior (AP) and medial-lateral (ML) lengths of the tibia were measured on computed tomography scans and intraoperatively on tibial resection surfaces. A special small component is unnecessary, and size variation should focus on ML length of 65 to 75 mm because this includes 90% of women's knees. AP-to-ML ratio had a negative correlation with ML length, indicating that small knees were longer in the AP direction. Most prostheses had AP mismatch up to 5 mm for small women's knees. These data could provide the basis for designing the optimal tibial component for most of the Asian-Pacific population.

Aged↗

PubMed2002

One-stage treatment of chronic osteomyelitis of the proximal tibia using a pedicled vascularised double-barrel fibular flap together with a muscle flap.

Although segmental bone loss together with a soft-tissue defect after debridement of a chronic osteomyelitic lesion of the tibia represents a challenging problem for the reconstructive surgeon, bone management has not usually been carried out at the time of soft-tissue coverage. In a one-stage procedure, we treated a patient who had suffered from chronic osteomyelitis of the tibia for 12 years, using a pedicled vascularised double-barrel fibular flap together with a pedicled medial gastrocnemius muscle flap, immediately after radical debridement of the osteomyelitic lesion. Bony union was obtained at 4 months. Full unprotected weight-bearing for normal walking was achieved 10 months after fibular transfer. Follow-up at 2 years showed no recurrence of the osteomyelitis.

Aged↗

PubMed2000

Immunolocalization of stress proteins and extracellular matrix proteins in the rat tibia.

Stress proteins (heat shock proteins [hsps]) serve a number of protective functions, including protection from apoptosis and acting as chaperones during protein biosynthesis. For example, hsp 27 has been defined as a chaperone for the G3 domain of aggrecan, while hsp 47 is the chaperone for type I collagen. Separate cytoprotective roles for hsp 27 and hsp 70 have been demonstrated. The aim of this study was to define the expression of hsps in osteoblastic and chondrocytic cells of the growing rat long bone in relationship to the immunohistochemical localization of aggrecan, type I collagen and the presence of fragmented DNA that defines apoptotic events. Tibiae were harvested from Fisher 344 rats (n=6) and fixed in 10% buffered formalin. Samples were decalcified in 10% EDTA, bisected, and processed for histologic examination. Sections (5 mm) were immunohistochemically stained using a streptavidin-biotin detection method. Co-localization of hsps with apoptosis was achieved using the TUNEL procedure. In the rat tibia growth plate, aggrecan was generally distributed throughout cartilage and chondrocytes. However, hsp 27 expression was observed only in the lower hypertrophic chondrocytes. hsp27 was present in osteoblasts lining newly formed bone. hsp 47 staining was also prominent within these osteoblasts where collagen type I immunolocalization occurred. The inducible form of hsp 70 was localized to the osteoblastic cells lining new bone in the primary spongiosa. In cartilage, DNA fragmentation was restricted to the hypertrophic, hsp27-positive, chondrocytes. In contrast, DNA fragmentation was not co-localized with hsp27-positive osteoblastic cells of the primary spongiosa, although occasional apoptotic cells were identified. These results indicate that apoptosis is a mechanism by which hypertrophic chondrocytes are eliminated from cartilage prior to calcification, but that other mechanisms are also likely to be involved. They also suggest that hsps have cytoprotective and biosynthetic functions within osteoblasts and chondrocytes, but apoptotic signals may override these effects in some instances, resulting in apoptosis.

Aggrecans↗

PubMed1986

Oestradiol and testosterone binding sites in mice tibiae and their relationship with bone growth.

High affinity oestradiol and testosterone binding sites were found in tibiae cytosol from entire male and female of different ages. Scatchard assay allowed to estimate a Kd of 2.7 X 10(-9) M for oestradiol binding sites indicating that the 3H-oestradiol binding was of high affinity. Oestradiol and testosterone binding sites abundance in mice tibiae are subject to change with age. It is not easy to establish a direct correlation between these changes and the values reported here on bone growth in weight and length, however seems possible to point a negative relationship between bone lengthening and oestradiol binding site levels in female, as well a positive relationship with testosterone in both sexes. The presence of oestradiol and testosterone binding sites in epiphyses and not in the diaphyses reinforces the hypothesis that both are playing some role in bone growth.

Age Factors↗

PubMedDate not supplied

[Corrective osteotomy of the shaft of the femur and tibia with an interlocking nail].

The indication for nailing a femur or tibia fracture has been extended by the method of interlocking up to the meta/diaphyseal zone. For the stabilization of osteotomies in these regions, the nail was used in 16 cases of femur and 21 of tibia corrections between 1982 and 1986 in orthopedic university clinic Berlin. The osteotomies were done with a small skin incision in open way. Although there were three infections bone consolidation was succeeded in all but one patient with the planned axis. The first achieved gain in length could not be hold in five cases after removing the interlocking screws in order to give full weight bearing to the leg for callus formation. In situations of non-unions with wrong position of refracture of biologically troubled bones after plating the method of interlocking nail is stable and enables bone recovery after grafting by drilling. The possibility of early full weight bearing is a great advantage for the rehabilitation of patients, who had been suffering of the delayed healing of their leg. The nail itself preserves the right position of the bone in two dimensions, even if there are not exact fitting osteotomy fragments, and the interlocking screws secure the bone against malrotation.

Adolescent↗

PubMedDate not supplied

[Relation between distribution of roentgen density and tensile strength to pressure and tension in the shaft center of the human tibia].

Investigations on 12 tibiae of 6 male corpses (68-81 years). In radiographs of cross-sectional slices from the middle of the shaft, the distribution of the density has been investigated by the method of Konermann (1971) and calibrated by a staircase of aluminium. In samples, taken from the positions anterior, medial, posterior and lateral, proximally and distally of the cross-section, tensile and compressive strength has been determined. From the results is concluded, that there exists functional adaptation of mechanical stress in the central part of the tibia with the following pattern: adaptation to tension at the locations anterior and medial, and adaptation to compression at the locations posterior and lateral. At the compression-side there is an additional adaptation by increased density.

Absorptiometry, Photon↗

PubMed2001

Flexion of the knee increases the distance between the popliteal artery and the proximal tibia: MRI measurements in 15 volunteers.

We determined which angle of flexion best prevents popliteal artery injury during knee surgery. We took MRIs of the knee in the lateral position with the knee in 0 degrees, 45 degrees, 90 degrees, and 120 degrees of flexion in 15 volunteers. The shortest distance between the posterior cortex of the tibia and the popliteal artery was measured at various levels from the knee joint to 60 mm distally. At the level of the joint and 15 mm distally, the distance between the tibia and artery increased with increasing knee flexion. More distally, no significant difference was noted with increasing flexion. Flexion of the knee may minimize injury to the popliteal artery in procedures between the level of the joint and 15 mm distal to the joint.

Adult↗

PubMed2005

Gross osteolytic tibia tunnel widening with the use of Gore-Tex anterior cruciate ligament prosthesis: a radiological, arthrometric and clinical evaluation of 17 patients 13-15 years after surgery.

BACKGROUND: Postoperative widening of the bone tunnels have been found after anterior cruciate ligament reconstruction using autologus bone-patellar tendon-bone or hamstring tendon grafts. These changes seem to be of no clinical significance in a short to midterm follow-up. We investigated if a synthetic graft evokes the same bone tunnel widening and if it is of clinical significance in a longterm follow-up. METHODS: We examined 17 patients, 13-15 years after their anterior cruciate ligament reconstruction using a Gore-Tex ligament prosthesis. The follow-up consisted of clinical examination, K-1000 arthrometric measurement, Tegner, Lysholm and IKDC scores, and CT examination of their tibia bone tunnels. 6 patients had been reoperated before follow-up, 3 because of graft rupture and 3 because of effusion and/or pain. RESULTS: 5 patients were graded as normal (n = 2) or nearly normal according to the IKDC score, and 4 of these patients still had their Gore-Tex prosthesis intact. 15 of the patients had a tibia bone tunnel wider than the drilled 7.9 mm diameter, ranging from 9.6 to 26 mm. These changes in the bone tunnels were in some cases without symptoms and could not be detected with arthroscopy, clinical examination, arthrometry or evaluation scores. We do not know whether they are progressive. INTERPRETATION: Based on our findings, we recommend that patients who have had a Gore-Tex anterior cruciate ligament reconstruction should be examined not only clinically or by questionnaire, but also with CT.

Adolescent↗

PubMed2005

Experimental renal failure and iron overload: a histomorphometric study in rat tibia.

Renal failure (RF) is a serious disease of relatively high incidence, known to cause bone alterations. RF patients frequently suffer anemia, which is usually treated with iron. Given that iron overload inhibits bone formation, the aim of the present study was to evaluate the effect of iron on the subchondral bone of rat tibiae, using a model of renal failure. Male Wistar rats were subjected to experimental nephrectomy in order to induce renal failure and to iron overload by daily intraperitoneal injections of 88 mg/kg body weight of iron-dextran for 16 days. Tetracyclines were injected intraperitoneally to evaluate dynamic parameters of bone. Undecalcified histological sections of the tibiae were obtained. Serum urea, creatinine, and paratohormone (PTH) levels were evaluated 30 days after the onset of the experiment. Static and dynamic histomorphometric measurements were performed. Iron overload modified the response of the animals with renal failure: a reduction in bone forming activity compatible with adynamic bone disease and a decrease in peritrabecular fibrosis were observed. Our results suggest that iron is yet one more factor involved in the imbalance in bone metabolism typically found in renal failure patients treated with iron, rendering diagnosis and treatment of bone disease in these patients more complex.

Animals↗

PubMed2004

The effect of tibial curvature and fibular loading on the tibia index.

The tibia index (TI) is commonly used to predict leg injury based on measurements taken by an anthropomorphic test device (ATD). The TI consists of an interaction formula that combines axial loading and bending plus a supplemental compressive force criterion. Current ATD lower limbs lack geometric biofidelity with regard to tibial curvature and fibular load-sharing. Due to differences in tibial curvature, the midshaft moments induced by axial loading are different in humans and ATDs. Midshaft tibial loading in the human is also reduced by load-sharing through the fibula, which is not replicated in current ATDs. In this study, tibial curvature and fibular load-sharing are quantified through CT imaging and biomechanical testing, and equations are presented to correct ATD measurements to reflect the loading that would be experienced by a human tibia.

Adult↗

PubMed1990

Pulmonary metastases of a tibia adamantinoma. Case report and review of the literature.

An adamantinoma is a rare primary tumour of bone. It is usually seen by stomatologists as a tumour of the jaws, although several cases of the long bones, especially the tibia, have been described. The tumour is considered as a low grade malignancy with unknown histogenesis. It has a high rate of local recurrence after resection and metastasizes in part of the cases. This report describes a 41-year-old woman with multiple pulmonary metastases occurring 27 years after the diagnosis of a tibia adamantinoma. The clinical, radiographic and fiber-bronchoscopic findings are presented. The literature of adamantinoma metastasis is reviewed. The need for an early locally aggressive treatment is stressed as the treatment of metastatic disease seems very disappointing.

Adult↗

PubMed2005

XeCl excimer laser ablation of rabbit tibia bone: morphology of the irradiated site and self-limiting effect.

OBJECTIVE: The purpose of this work is to investigate the morphological changes of the rabbit tibia bone submitted to osteotomy with XeCl excimer laser. BACKGROUND DATA: Laser ablation of tissue is a relevant clinical application of high-power lasers. Due to the variety of laser wavelengths and properties of biological targets, the subject has not yet been completely explored. METHODS: In this study, four tibias were irradiated with six different durations. The applied energy density was 6.7 J/cm(2) per pulse at a 4-Hz repetition rate. RESULTS: The 24 samples had similar and well-defined craters that were free of carbonization. The ablation rates per pulse, at 60-120 seconds, were 3.8 and 1.9 microm at the compact bone and the marrow tissue, respectively. The ablation process ceased after 120 sec, with a 1.6-mm crater depth. CONCLUSIONS: In the present study, the laser used showed a self-limiting characteristic, which is a phenomenon that can be of great value in preserving important structures close to the working area, giving a margin of safety to the surgeon, in case of over-irradiation. This self-limiting effect is attributed to liquid filling the cavity by the bleeding and irrigation process.

Animals↗

PubMedDate not supplied

Osteopenia in alcoholics after tibia shaft fractures.

A marked reduction of 40-70% in regional bone mineral density (BMD) has been reported after fractures of long bones, and this post-traumatic osteopenia may to some extent persist for several years, perhaps lifelong. In this cross-sectional study, we investigated whether prolonged alcohol abuse had any effect on the degree of post-traumatic osteopenia after isolated tibia shaft fractures, the rationale for such a suspicion being the deranged bone metabolism found in alcoholics. We also wanted to investigate whether dual energy X-ray absorptiometry (DEXA) or quantitative ultrasound technique could detect differences between abusers and non-abusers in post-traumatic bone loss. We measured the BMD in 61 male patients with isolated tibia shaft fractures (1984-94) with the Lunar DPX-L and the Lunar Achilles. Twenty-four of the patients were verified to be high consumers of alcohol. After correction for differences in age and the time elapsed since the fracture event, we found significantly lower (11%; P = 0.017) BMD in the femoral neck of the fractured leg in abusers when utilizing the DEXA technique. No differences between abusers and non-abusers in BMD were detectable when using the ultrasound technique. We found a fair correlation (r = 0.63-0.81) between the DEXA and the ultrasound techniques in regions with spongious bone. Our findings suggest that alcohol abuse has some, albeit a limited, effect on the degree of post-traumatic osteopenia and that ultrasound measurements in the calcaneus are of little use in detecting an increased post-traumatic osteopenia in this patient group.

Adult↗