Osteology: Estimating Femur Length from the Diameter of the Femoral Shaft

School of Biological & Earth Sciences BIEGN3005 Honours Project March 2010 educatee name Stephen Dempsey Supervisor name Professor Alan Turner Estimating thighbone distance from the diam of the femoral shaft Stephen Dempsey BIEGN300 Honours Project Person amount 343106 Submission Date 5th March 2010 Abstract Bone lengths sewer be used to provide peak estimations in case of unsung cadaverous remains, an important as well asl in forensic and bioarchaelogical cases. Where the bones be broken or fragmented, regression equations tooshie be used to visualise total bone length from its fragments, which in turn can be used to estimate tiptop.The aim of this probe was to test 2 tonic measurements of the femoral shaft to see if they could be used as predictors of supreme femoral length. The token(prenominal) transverse femoral shaft diameter and the minimum anterior-posterior femoral shaft where mensural on a small sample distribution of an archaeological population from P oulton, Cheshire, along with the maximum femur length for distributively sample. Simple linear regression psycho compend was performed and the results showed that the minimum transverse femoral shaft diameter correlated monumentally in both males (R2=. 635, p=0. 006) and females (R2=0. 8, p=? 0. 001) with maximum femur length. The minimum anterior-posterior femoral shaft diameter showed no significant correlativity with maximum femur length. Subsequently, regression equations were presented for the significant correlations. Further research is needed to validate the results and to improve the accuracy of the method. 1. presentation The role of a forensic anthropologist in forensic and archaeological cases is to engraft demographics (population affinity, age, sex and stature), time since death and cause of death from an privates remains (Chibba et al, 2006).The use of stature as a biological distinctive of identity can significantly contribute to the identification of unknown skeletal remains. Numerous areas of the skeleton have been used to try and determine an individuals living height such as the upper arm bones (Rao et al. 1989), lower limb bones (Trotter and Gleeson, 1952), the metatarsals (Cordiero et al, 2009) and the skull (Ryan and Bidmos, 2007). Hauser et al. (2005) provide a near review of the past research in the area of stature estimation. unmatchable of the methods used in the estimation of stature is the formulation of regression equations from measurements of miscellaneous bone lengths.Pearson (1899) was the first to derive regression equations for estimating stature, and since then it has grown to be the method of choice among most anthropologists. M some(prenominal) of the methods used to approximate stature require complete or near complete bones, so thus few studies have been done on incomplete or fractional bones (Bidmos, 2008). Forensic anthropologists are often confronted with fragmented bones and in these cases it is imposs ible to derive regression equations directly from bone length (Rao et al. 989). Wright and Vasquez (2003) plead the problems they faced in Guatemala in which they were often unable to estimate stature from bone length due to the rapid deterioration of bone in the tropical environment. This is only one of many detailors that lead to the all too frequent recovery of broken or fragmented remains. Therefore it is advantageous to have equations available for bone length or stature derived from measurements of little segments or landmarks on the chosen bone.The femur is the favoured bone of use among anthropologists in estimating stature, due to its high correlation with height in addition to the fact that it is one of bones most often recovered (Simmons et al. 1990). A offspring of measurements of the femur have already been reported to have good correlations with femur length. Many of these measurements focus on the proximal and distal ends of the femur such as the upper epicondyla r length, epicondylar breath, vertical neck diameter and the bicondylar breathe (Brauer, 1988), nonetheless few have focused on measurements of the femoral shaft.This pilot study looks to test the validity of 2 measurements from the femoral shaft as predictors of maximum femoral length. The points of reference chose on the femur are the minimum transverse femoral shaft diameter (TRD) and the minimum anterior-posterior diameter (APD) of the femoral shaft. The samples organism used are that of an archaeological population recovered from a mediaeval cemetery in Poulton, Cheshire. The aim is to use linear regression analysis to test the assumption that there is a significant correlation amid these measurements and the maximum femoral length.A further aim is to produce regression equations that can be used on other skeletal remains from the Poulton sight for estimating maximum femur length. 2. Materials and Methods 2. 1 Samples The samples used in this study were obtained from the Po ulton collecting housed at Liverpool John Morres University. Due to the small size of the collection at present and the poor condition of some of the bones, a total takings of 18 left sided femora were selected for use in the study. These femora were chosen on the behind of completeness and measurability. exclusively the samples were obtained from adults skeletal remains and the number of male and females femora was 10 and 8 respectively. 2. 2 Measurements The following 3 measurements were taken on each of the 18 samples i. supreme length of the femur (MAXL) ii. borderline anterior-posterior femoral shaft diameter (APD) iii. Minimum transverse femoral shaft diameter (TRD) The MAXL measurement was taken as described by Brauer (1988). The APD and TRD measurements were taken as described by Ziylin and Mursid (2002). The MAXL was measured using an osteometric board.The APD and TRD were measured using a sliding callipers with an accuracy of 0. 1 mm. Linear regression analysis was ca rried using the SPSS statistic program to see if any correlation existed between the measurements taken of the femoral shaft (APD and TRD) and the maximum length of the femur. All analysis was carried out separately for males and females on the advice of Trotter and Gleser (1952) who subject the specificity of such measurements in relation to sex. 3. Results The descriptive statistics for males and females are shown in circuit board 1. Males showed the highest mean values of each of the 3 measurements taken.Males also showed the higher commonplace digressions in respect to MAXL and APD, with females showing a higher standard deviation for TRD. duck 1 Descriptive statistics for measurements of male and female left femora. All descriptive values are given in mm. Measurements Male distaff N Mean Std. dev N Mean Std. dev MAXL 10 466. 60 16. 965 8 429. 13 11. 643 TRD 10 27. 910 1. 365 8 24. 725 1. 752 APD 10 28. 190 2. 497 8 27. 138 1. 840 Table 2 shows the results of the linear regression analysis that was performed. Both APD and TRD were regressed against MAXL according to sex.The analysis showed that the variable APD showed no significant correlation to MAXL for males (R2=0. 154, P=0. 262) or females (R2=0. 044, P=0. 619). TRD provided more positive results showing a moderate significant correlation in respect to males (R2=0. 635, P=0. 006), and a strong significant correlation in respect to females (R2=0. 88, P=0. 01 (Table 2) and the standard error of the estimated being