Could irrigation, debridement and antibiotic therapy cure an infection of a total hip arthroplasty?

Seven patients suffering from an acute (less than two weeks) infection of a total hip arthroplasty were treated by irrigation and debridement, with appropriate antibiotic therapy and retention of the prosthesis. They were followed for an average of 30 months. Infection did not recur in five (71%) patients, but the other two required further surgery. We conclude that a cure can be obtained by this method, although the results are inferior to re-implantation. A minimal procedure spares a patient the morbidity and cost of a more extensive operation. Higher success rates might have been achieved by selecting patients infected with organisms of low virulence, but there are insufficient data to predict whether this treatment would decrease the success of subsequent re-implantation.

Ankle arthrodesis using the Ilizarov apparatus: good results in 6 patients.

We report our experience with the Ilizarov apparatus in performing ankle arthrodesis in 6 patients. The average age of the patients was 52 (42-60) years. 3 patients had posttraumatic arthrosis and active infection of the ankle or distal tibia and the other 3 had posttraumatic arthrosis of the ankle without infection. Solid and painless arthrodesis was achieved in all patients in 7-15 weeks, including those with an active infection or failed multiple previous operations. While the method is useful for primary treatment of ankle arthrosis, we think it is better for treatment of certain complicated cases.

Genetic variation and covariation of parathyroid hormone levels and bone density in the human population.

The present study was an attempt to evaluate the relative importance of familial/genetic factors in interindividual variation of plasma concentrations of parathyroid hormone (PTH) and bone mineral density (BMD). We also examined to what extent common genetic and environmental factors may be involved in covariation between the hormone concentrations and BMD levels. Ninety-five nuclear pedigrees (consisting of 187 males and 168 females, aged 18-91 and 18-86 years old, respectively), from several small villages in the Chuvasha Autonomy, Russia, were assessed for PTH, sex hormones, and BMD. PTH plasma levels were measured in duplicate by immunoradiometric assay using an N-tact PTH SP kit. Standard roentgenography was done from the second and third phalanges of the middle finger on both hands for assessment of compact and cancellous bone BMD separately. The present study clearly confirmed the results of the previous genetic analyses of BMD which indicated that between 47% and 60% of the total variance of BMD, adjusted for sex and age effects, were attributable to genetic factors. Genetic factors also contributed significantly to interindividual variation of PTH. Constraining these additive genetic effects to zero dramatically increased the likelihood ratio (P < 0.001), indicating that at least 30% of the hormone plasma variation was attributable to genetic sources. The results of bivariate decomposition analysis were not clear cut. Two types of bivariate analyses showed that PTH-BMD genetic correlations according to sex and between the opposite sexes were consistently negative, but only marginally significant.

Reduced NO accumulation in arthrotic cartilage by exposure to methylene blue.

Nitric oxide (NO) appears to be a final common inflammation mediator of cartilage degradation. Halting the pathological formation of excessive NO, by suppressing the inducible NO synthase (iNOS) activity, may help to preserve cartilage integrity. We used fresh ex-vivo human articular cartilage explants from normal and arthrotic joints for assessment of NO levels, as determined by its nitrite degradation products and nitric oxide synthase expression. We measured matrix proteoglycan content, assessed by image analysis of alcian blue staining, and proteoglycan synthesis, assessed by sulfate incorporation into proteoglycans. The effect of methylene blue, a nitric oxide synthase inhibitor, on matrix preservation was evaluated. Cartilage discs in vitro, derived from normal appearing joints, secreted about one tenth as much NO compared to discs derived from arthrotic cartilage. Cartilage explants showed a time-dependent reduction in the amount of aggrecan within the cartilaginous matrix. Addition of methylene blue to the growth medium lowered nitric oxide accumulation and prevented matrix degradation in the cultured cartilage discs. The cartilage matrix preservation effect was mediated through downregulation of all three isoforms of NOS, i.e., the neuronal NOS, endothelial NOS and inducible NOS and upregulation of TGF beta receptor in the chondrocytes. Our findings indicate that inhibition of NOS activity preserves cartilage matrix in vitro.

Mennen paraskeletal plate fixation for fracture of the femoral shaft in association with ipsilateral hip arthroplasty.

We reviewed the results of Mennen paraskeletal plate fixation in 14 patients with fracture of the femoral shaft in association with a previously successful ipsilateral hip arthroplasty. Overall good results were obtained with undisplaced fractures but some of the results in those individuals with widely displaced and unstable fractures were disappointing leading to some serious complications including amputation. The paraskeletal plate appears then to be no more than an internal splint and caution needs to be exercised when this device is used in this situation.

Femoral bone reconstruction in revision total hip replacement.

Twelve patients who had undergone total hip replacement complicated by aseptic loosening with severe bone loss were included in this study. Eight of these patients had aseptic loosening of more than the second revision and the remaining four patients of the fourth revision total hip replacement. In all patients, the radiographs revealed an extremely thin cortex around the stem of the prosthesis and almost disappearance of one cortex. All patients were treated by revision total hip replacement in conjunction with Mennen plate fixation and bone graft support. The results were satisfactory in ten patients in respect to functional activity, pain, and radiographic evaluation. In two patients who underwent their fifth revision, the results were unsatisfactory but better than that before the operation. Our conclusion is that Mennen plate fixation provides a sufficient and easy operative technique for the correction of aseptic loosening of total hip prostheses accompanied by severe bone loss.

Aging bone score and climatic factors.

Hand radiograms for osseographic assessment of bone aging status were taken from more than 7,500 individuals residing in 31 different localities and belonging to 20 ethnic groups. Multiple regression analysis was used to evaluate possible associations between bone aging parameters and several climatic factors, to wit: hours of daylight in January and July, average monthly humidity and partial vapor pressure in January and July, and one climatic index pertaining to comfort conditions in life, namely, the Bioclimatic Index of Severity of Climatic Regime. Multiple regression analysis clearly pointed to significant correlations between climatic characteristics and indices defining the relative rate of bone aging in humans; it also evinced an independent contribution of July's humidity and January's mean temperature to earliest age at which first signs of bone aging can be found. In sum, there are grounds for concluding that temperature and humidity are key factors in triggering initial bone changes in individuals within the human populations prone to environmental effects. The combination of humidity and temperature with other factors which reflect the sharpness of the interseasonal differences in climatic conditions predispose the populations to early onset of bone changes.

The metabolism of vitamin D3 in response to testosterone.

Sex steroids were suggested as regulators of vitamin D metabolism. While considerable data is available regarding interaction between estradiol and vitamin D, very little is known about interactions between testosterone and vitamin D. A similar gap exists with regard to the involvement of the vitamin D endocrine system in the pathogenesis of the female versus the male osteoporosis syndrome. In the present study we studied the effect of long-term treatment with testosterone on the metabolism of vitamin D in vitamin D3 replete sexually immature male chicks. We were able to show under this treatment, circulating levels of 1,25-dihydroxy vitamin D3 (1,25(OH)2D3) are significantly reduced, but intestine and bone concentrations are significantly increased. The increased concentration of 1,25(OH)2D3 in bone was accompanied by an increase in the ash content of this tissue. The reduction in serum 1,25(OH)2D3 was not dependent on reduced activity of the renal 25-hydroxy vitamin D3 - alpha - hydroxylase. Based on these findings it is proposed that testosterone is involved in the stimulation of the biological response to vitamin D in the classical target-organs, such as intestine and bone, and this observation may provide partial explanation to the pathogenesis of osteoporosis in hypogonadal men.

Geographic variation in vascular mortality in Eurasia: spatial autocorrelation analysis of mortality variables and risk factors.

The geographic variation patterns of vascular mortality and their major risk factors from 68 samples in Eurasia are described in this work. The goodness-of-fit tests and analysis of variance indicate significant differences in incidence of mortality from the studied diseases, as well as in risk factors among the various geographic regions in four age groups. Correlation analysis points out the two general tendencies for the majority of studied traits: (a) significant positive association with latitude and (b) significant negative correlation with longitude. In turn, one-dimensional correlograms showed no specific geographic pattern at least up to 3000 km for all studied variables. However, at the large geographic scale a long-distance differentiation pattern was indicated for total serum cholesterol and body mass index; regional patches--for total death rate, mortality rate from cardiovascular and ischaemic heart diseases, systolic and diastolic blood pressure; and a local patches pattern was detected for mortality rate from stroke. Two-dimensional correlograms uncovered three distinct and significant patterns of variation: (a) a north-south trend for total mortality rate, for death rate from cardiovascular and ischaemic heart diseases, for diastolic and systolic blood pressure and for body mass index; (b) a northwest-southeast pattern for mortality rate from cerebrovascular disease; and (c) local patches for total serum cholesterol.

Amniotic fluid and plasma levels of parathyroid hormone-related protein and hormonal modulation of its secretion by amniotic fluid cells.

Parathyroid hormone-related (PTHrP), the major mediator of humoral hypercalcemia of malignancy, may also regulate placental calcium flux, uterine contraction and fetal tissue development. In the present study, we demonstrated that the mean immunoreactive PTHrP concentrations in amniotic fluid at mid-gestation (21.2 +/- 3.7 pmol/l) and at term (19.0 +/- 2.7 pmol/l) were 13-16-fold higher than levels measured in either fetal (1.6 +/- 0.1 pmol/l) or maternal plasma (1.4 +/- 0.3 pmol/l) at term and equal to levels found in plasma of patients with humoral hypercalcemia of malignancy. In vitro studies pointed to three possible sources of PTHrP in amniotic fluid: cultured amniotic fluid cells, cells derived from the amniotic membrane overlying the placenta and placental villous core mesenchymal cells. Treatment of cultured amniotic fluid cells with human prolactin, human placental lactogen (hPL) or human growth hormone (100 micrograms/l) increased PTHrP secretion after 24 h by 43%, 109% and 90%, respectively. Insulin-like growth factors I and II (100 micrograms/l), insulin (100 micrograms/l) and epidermal growth factor (EGF) (10 micrograms/l) increased PTHrP secretion by 53%, 46%, 68% and 118%, respectively. The stimulation of PTHrP secretion by EGF or by hPL was both time- and dose-dependent. In contrast, calcitriol and dexamethasone (10 nmol/l) decreased PTHrP secretion by 32% and 75%, respectively. Estradiol, progesterone, dihydrotestosterone and human chorionic gonadotropin had no effect on PTHrP secretion. These findings support the notion that PTHrP may play a physiological role in the uteroplacental unit and demonstrate that human amniotic fluid cells could be a useful model for studying the regulation of PTHrP production and secretion by hormones and growth factors.

Genetics of human body size and shape: complex segregation analysis.

The genetic component in a mixed heritability model, including major gene, multifactorial and sibling environment transmissible components, was studied for some 20 anthropometric traits in two ethnically different samples. The first sample comprised 305 Mexican nuclear families, and the second comprised 83 Ashkenazi Jewish nuclear families living in Israel. All variables, after adjustment for age and sex, were subjected to principal-components analysis (PCA) in each sample separately. The mixed model of inheritance as implemented in the computer program POINTER was used in the present study. An attempt was made to evaluate genetic effects in the variation of the first principal components (PCs). PCA showed a clear separation of variables and was easily interpretable. The PC1 was a credibly general size factor. This factor alone accounted for about 30% of the total variance. Other components are rather shape factors for various combinations of traits. The testing of several genetic hypothesis showed the following: (1) For all factor scores the genetic component was high and statistically significant. (2) In a Mexican sample, for PC1 and PC2, both major gene and polygenes contributed significantly to the total variation of these variables; in the major locus the alleles were most probably codominant. (3) For all other PCs the major gene effect hypothesis was rejected, with more than 50% of the variation attributable to the polygenes contribution. (4) No evidence was found for sibling environmental resemblance in either sample.

Calcium cells from snails: response to vitamin D metabolites.

Calcium is one of the most important substances affecting the life of molluscs, and vitamin D was shown to be an essential nutrient for land snails. In an attempt to elucidate the role that vitamin D plays in calcium metabolism of land snails, we have developed a procedure for the isolation of specialized calcium cells from digestive gland of land snails, and were able to culture these cells. The effect of vitamin D metabolites on the intracellular exchangeable calcium and alkaline phosphatase activity was studied. The metabolites tested were 25-hydroxycholecalciferol (25(OH)D3), 24,25-dihydroxycholecalciferol (24,25(OH)2D3), 1,25-dihydroxycholecalciferol (1,25(OH)2D3), and the molluscan metabolite E. 25(OH)D3 was found to be the most active sterol in elevating intracellular exchangeable calcium and the activity of alkaline phosphatase, and the molluscan metabolite E was found to be the most potent sterol in the suppression of alkaline phosphatase activity. 1,25(OH)2D3 was shown to suppress both activities at high concentrations, and 24,25(OH)2D3 increased the intracellular exchangeable calcium only at high concentrations. Thus, 25(OH)D3 which is regarded as a storage form of vitamin D and devoid of biological activity, seems to be biologically active in invertebrates.

The effect of hyperthermia (42.5 degrees C) on zymosan-induced synovitis of the knee.

Though heat has been used for many years for the treatment of painful joints such therapy rarely increases the intra-articular temperature significantly. This pilot study investigated the effect of intra-articular hyperthermia induced by microwaves from a combined heating/cooling instrument on zymosan-induced synovitis in the rabbit. There was histological evidence not only of a reduction in the intensity of the inflammatory response but also in its type with the absence of giant cell formation. However, hyperthermia was not totally without effect on the synovium of control joints and further studies are required to investigate the relevance of this effect.

Biology of aging in an Israeli population. 2. Polymorphic blood markers and fluctuating asymmetry.

The major objectives of the present study were to detect whether there are any differences in genetic blood markers distribution between the young and old Israeli population. We also investigated the question about the relationship between the genetic heterozygosity (H) and fluctuating asymmetry (FA) of an individual. The study sample consisted of 208 elderly people aged between 75 and 94 years old. Each individual was assessed for the same 18 anthropological traits, 8 of which were paired bilateral structures and 10 were size and mass measurements. Thirteen polymorphic gene markers were also taken from each individual. Most of the studied gene systems showed no inter-group (old sample vs 207 young individuals) differences. Significant differences were detected at ADA, ESD, GTP1 and FY loci. These differences were mainly due for the considerably lower frequency of the heterozygous individuals in elderly samples. Our working hypothesis at the next stage of the analysis were as follows: 1. Morphologically central phenotypes are more symmetric (processes lower FA) than morphologically extreme individuals. 2. There is a detectable negative correlation between the FA and individuals H. To study these questions we developed a multivariate measure of FA and morphological deviation of the individual from the population centroid. Yet, no reliable evidence in support of either of the two hypotheses were obtained.

Biology of aging in an Israeli population. 1. Review of literature and morphological variation analysis.

This article reports the results of a comparative morphological assessment carried out on five age segments of an Israeli population: 1. neonates, 2. early school age children (6.5-7.5 years old), 3. young adults (18-29), 4. mature adults (30-45) and 5. elderly people (75-94). The aim of the investigation was to analyze the relationship between developmental homeostasis phenomena and the aging process. Developmental homeostasis was assessed via group coefficient of variation (CV) for 21 morphological traits and fluctuating asymmetry (FA) for 8 bilateral traits. The majority of traits was found to show significantly increased CV and FA in the elderly group. This finding is consistent with the hypothesis that the aging process is accompanied by the total breakdown of the individual's developmental stability.