Male Femur Research Articles

Sex determination from the head of the femur of South African whites and blacks

The current practice whereby criminals dismember the remains of their victims in an attempt to make their identification difficult requires that simple methods of sex determination from fragmented skeletal remains are available to forensic anthropologists and skeletal biologists. The head of the femur is an example of such bone fragments. Identification and demarking points have been derived from the diameters of the head of the femur and used to determine the sex of individuals. It has been shown, however, that the numerical values of these parameters that permit sex identification vary between races. The objectives of the present study were therefore to establish the standard numerical values of the identification and demarking points for sex determination in South African whites and blacks and to see if these standards are different in the two races. A total of 520 femurs of white (160 males and 100 females) and black (160 males and 100 females) South Africans were obtained from the Raymond Dart Skeletal Collection in the Department of Anatomical Sciences of the University of the Witwatersrand, Johannesburg, South Africa. The vertical and transverse diameters of the heads of the femurs were measured by means of a stainless steel vernier caliper. Identification and demarking points were derived from the values of these diameters. The head diameter identification point and demarking point were found to be sexually dimorphic in both white and black South Africans. The mean head diameter of the male femur was significantly greater than the mean head diameter of the female femur in both population groups (significant at P<0.001). These values were correspondingly greater in the white than the black population. The numerical values of the male identification and demarking points were higher than the corresponding female values in the two population. In both sexes, these values were greater in the whites than the blacks South Africans. It is concluded that the diameters of the head of the femur and the identification and demarking points that are derived from them are sexually dimorphic in South African white and black populations. However, the numerical values of these sex-determining bone parameters defer between the two population groups. Therefore, it is necessary to determine race-specific standards of these parameters.

A Comparative Study of Femoral Head Diameters and Sex Differentiation in Nigerians

The vertical and transverse diameters of the head of 504 paired human femurs (257 males and 247 females) from Maiduguri in the northeastern arid zone of Nigeria were measured. Identification points and demarking points were determined. The mean diameter of the head of the male femur was significantly greater than that of the female (p <0.001). The identification points that were derived from the vertical and transverse diameters of the head of the femur were higher in males than in females. Those that were derived from the vertical diameters of the head of the male femurs were comparable to the values from the southeastern part of Nigeria. Those that were derived from transverse diameters were lower than the corresponding values from southeastern Nigeria. By means of identification points, more male bones were identified. This was due to the fact that the mean head diameter of female femurs fell within the range of diameters that did not permit positive identification of sex. The male demarking points were also higher than the corresponding female values. Similarly, the demarking point identified the sex of a higher percentage of male femurs. The demarking point, in comparison to the identification point, identified the sex of a smaller percentage of femurs. The results showed that diameters of the femoral head as well as the identification and demarking points that are derived from them are of use in sex and regional identification.

Stress shielding after total knee replacement may cause bone resorption in the distal femur.

Inadequate bone stock is often found in revision surgery of femoral components of total knee replacements. Our aim was to test the hypothesis that these remodelling patterns can be explained by stress shielding, and that prosthetic bonding characteristics affect maintenance of bone mass. We made a three-dimensional finite-element model of an average male femur with a cemented femoral knee component. This model was integrated with iterative remodelling procedures. Two extreme prosthetic bonding conditions were analysed and gradual changes in bone density were calculated. The long-term bone loss under the femoral knee component resembled clinical findings which confirms the hypothesis that stress shielding can cause distal femoral bone loss. Our study predicts, contrary to clinical findings, that an equilibrium situation is not reached after two years, but that bone resorption may continue. This hidden bone loss may be so drastic that large reconstructions are needed at the time of revision.

STRESS SHIELDING AFTER TOTAL KNEE REPLACEMENT MAY CAUSE BONE RESORPTION IN THE DISTAL FEMUR

Inadequate bone stock is often found in revision surgery of femoral components of total knee replacements. Our aim was to test the hypothesis that these remodelling patterns can be explained by stress shielding, and that prosthetic bonding characteristics affect maintenance of bone mass. We made a three-dimensional finite-element model of an average male femur with a cemented femoral knee component. This model was integrated with iterative remodelling procedures. Two extreme prosthetic bonding conditions were analysed and gradual changes in bone density were calculated. The long-term bone loss under the femoral knee component resembled clinical findings which confirms the hypothesis that stress shielding can cause distal femoral bone loss. Our study predicts, contrary to clinical findings, that an equilibrium situation is not reached after two years, but that bone resorption may continue. This hidden bone loss may be so drastic that large reconstructions are needed at the time of revision.

Measurement and relationship of the inclination angle, Alsberg angle and the angle between the anatomical and mechanical axes of the femur in males.

The present study was undertaken to determine whether there is a constant difference between the angle of inclination and the Alsberg angle and to evaluate statistical relationships between the inclination angle, Alsberg angle and the angle between the anatomical and mechanical axes of the femur. Measurements were taken from 50 male femurs (25 right and 25 left, aged 30-40 years) from the Anatomy Department, Cukurova University: inclination angle was determined between the neck and the shaft of the femur; Alsberg angle, between a line drawn through the base of the epiphyseal plate and shaft of the femur, and the angle between the anatomical and mechanical axes. The results showed that, for the right and left femurs respectively, the average inclination angle was 123.72 degrees and 125.96 degrees; the angle between the anatomical and mechanical axes was 6.24 degrees and 5.96 degrees; and the average Alsberg angle was 39.92 degrees and 40.61 degrees. The difference between the angle of inclination and the Alsberg angle in this study was 83.80 degrees and 85.36 degrees for the right and left femurs respectively. The correlation, coefficient between the angle of inclination and Alsberg angle was 0.96 and 0.93 for the right and left femurs respectively, while those between the angle between the anatomical and mechanical axes and inclination angle were -0.89 and -0.91 for the right and left femurs respectively. Furthermore, the correlation coefficient between the angle between the anatomical and mechanical axes and Alsberg angle were -0.88 and -0.90 for the right and left femurs respectively.

Analyses of measurements taken from adult femurs of a British population

AbstractThe femur remains an important bone in palaeoanthropology and this paper reports various analyses of measurements taken from long‐cassette radiographs of adult femurs of a reference population from the south of England (n=81, males 33, females 48). Discriminant analysis confirmed that the male femur is usually larger than the female femur, and that a femur may be sexed with some confidence. Discriminant scores have been derived to permit estimates to be made, from the whole or a part of a femur, of the probability of the male gender. Outcomes from a principal component analysis suggest: that the female proximal femur is a morphological unit; that neck length and shaft length are dissociated and there is no common factor representing linearity; and that the male bicondylar width is anomalous, a finding that is confirmed by other analyses. An estimate of the robusticity of the complete female, but not male, bone may sometimes be made from a proximal fragment. The robusticity of the complete bone may be made confidently from the shaft for both genders. The two width variables relating to a distal fragment cannot be used to predict the robusticity of the complete bone for either gender. A method of defining the position of the waist in terms of displacement in deciles down the shaft is described. The position of the waist seems to have a bimodal distribution. The positive association between age and distal displacement may be due to remoulding of the shaft with age or to a cohort (generational) effect. There is a weak correlation between a small neck–shaft angle and the distal displacement of the waist, two archaic phenotypic traits. Ten statements in the literature relating to the femur have been examined and tested; six are confirmed and four are unconfirmed, and it is suggested that there is a need for further studies relating to the morphology of the femur.

The Effect of Aging on the Shape of the Proximal Femur

The design of cementless femoral prostheses is based on the assumption that age and gender do not affect the shape of the proximal femur. To test this hypothesis, standard anteroposterior and lateral radiographs were prepared of 4 sets of 20 femora, obtained from young (range, 40-60 years) and elderly (range, 60-90 years) donors of both genders. The intracortical and extracortical borders of each femur were digitized electronically, and key parameters were measured to define the shape and dimensions of the medullary canal and the position of the femoral head. Systematic differences were observed between the size and shape of male and female femora. Extracortical dimensions were larger in the male femora by 14% to 19%, and endosteal dimensions by 11% to 24%. However, there were no significant differences between the canal shape of young male and young female femora in the coronal, sagittal, or transverse planes. The male femora displayed no significant differences in canal shape or endosteal width as a function of age. Profound differences were observed in the endosteal shape and diaphyseal dimensions of the young and old female femora. The older female femora had wider canals at the level of the isthmus, with a significant reduction in the canal flare index (the ratio between the canal width proximal to the lesser trochanter and at the isthmus). This study demonstrates that cementless femoral prostheses of 1 standard shape cannot provide a close fit to the endosteal contours of young and elderly women.

Determination of femur structural properties by geometric and material variables as a function of body weight in rats. Evidence of a sexual dimorphism

Femur diaphyses of male and female Wistar rats were densitometrically and biomechanically assayed. The BMD-dependent material properties were better in female than in male bones, but cross-section geometric properties were better in male femurs. As a result, mechanical properties of the integrated diaphyses were better in males, but differences disappeared after statistical adjustment of data to a common body weight. Results evidence a feed-back mechanism locally controlling the strain-dependent bone modelling and the corresponding cross-sectional design as related to bone stiffness, with a set-point adjusted to animal biomass. A sexual dimorphism of bone biomechanics is also described for the species.

Redefinition of Agria Robineau-Desvoidy, Angiometopa Brauer &amp; Bergenstamm and Toxonagria Shewell, with the description of a new species (Diptera: Sarcophagidae)

AbstractThe genera Agria Robineau-Desvoidy, 1830, Angiometopa Brauer &amp; Bergenstamm, 1889, and Toxonagria Shewell, 1987 are diagnosed and their monophyly discussed. Diagnostic character states for the three genera in their present definitions are: Agria: Phallic tube with a pair of lateral sclerotizations slanting antero-ventrally from the apex; acrophallus strongly tapering. Angiometopa: Gonostylus with membranous lobe at base; phallic tube with a pair of armlike processes encompassing base of acrophallus. Toxonagria: Male hind femur thickened and curved; male cercus straight; acrophallus with broad, membranous phallotreme; male gonocoxal lobe with an extra subapical tooth or hook. The name Omocera Lioy, 1864 (an objective senior synonym of Angiometopa) is preoccupied by Omocera Chevrolat, 1835 (Coleoptera: Chrysomelidae). Angiometopa is proposed as a senior synonym of Sarcofahrtia Parker, 1916, syn.n. Agria hikosana (Kurahashi, 1975), comb.n., Agria shinonagai (Kurahashi, 1975), comb.n., and Agria mihalyii (Rohdendorf &amp; Verves, 1978), comb.n. are transferred from their previous position in Angiometopa. Angiometopa bajkalensis Kolomyietz &amp; Artamonov, 1981 is recorded from the Nearctic Region for the first time (Canada: Alberta, British Columbia, Yukon), and Toxonagria arnaudi sp.n. is described from Canada (British Columbia) and USA (California).

On the structural symmetry of human femurs

The distribution of transverse and longitudinal lamellae from osteons and interstitial bone of the two femurs from a woman aged between 25 and 30 was investigated. Exactly plane parallel cross-sections (100 μm) were prepared from the upper, middle and lower thirds of the two bones. The distribution of transverse and longitudinal lamellae was determined for both osteonic and interstitial bone, using circularly polarised light. The results show that (a) as in the male femur, the transverse and longitudinal lamellae in these female femurs have a characteristic rotational distribution along the shaft consistent with the distribution of the bending strains normally operative in bone; and (b) the rotational distribution of the two types of lamellae is slightly asymmetrical in the two female bones, probably because of imperfectly symmetrical use of the lower limbs.

Femoral Head Diameters and Sex Differentiation in the Northern Zone (Rajshahi) of Bangladesh

This study was aimed to find out the variations of the femoral head diameters in relation to sex in Bangladeshi people. The study was based on 123 paired human femurs (radiological view) of which 52 were male and 71were female. It was observed that the mean vertical and transverse diameters of the head of the male femur were significantly greater than that of female (P&lt;0.001).No statistical significant difference was present between the measurement of the right and left side of the same sixth identification points that were derived from the vertical and transverse diameters of the head of the femur were higher in males than in females. The results showed that diameters of the femoral head as well as the identification points that are derived from them are of use in sex identification. The present study is of value to the forensic experts, orthopaedicians and prosthetists as it gives the idea about the dimensions of the femoral head in the present area. doi: 10.3329/taj.v18i2.3172 TAJ 2005; 18(2): 84-88