Formulae for Stature Estimation on Incomplete Long Bones
A Survey of theİr RcliabilitySHEILAGH BROOKS al, D. GENTRY STEELE b), RICHARD H. BROOKS .)
aL Department of Anthropology, University of Nevada, Las Vegas, USA
b) Texas A & M lJniversıty, College Station, Texas, USA
BAZI PARÇALARı
HESAPLANMASI tÇtN
BİR ARAŞTIRMA
Özet
EKSİK UZUN KEM1KLERLE BOY UZUNLUGUNUN
GELİŞTİRILMİş FORMÜLLER1N GEÇERLİLlG! ÜZERİNDE
American Academy of Forensic Sciences Fizik Antropoloji Bölümü üyeleri arasında yapılan bir ank,,~tle,
hazı parçalan eksik olan uzun kemiklerden yararlanarak boy uzunluğunun hesaplanması çalı~malarulln
verimliliği konusundaki görüşleri araşttrıldı. Bu tür çalışmaları yapan antropologlann %55'i bazı parçaları eksik kemikler üzerinde yaptıklan iııcelemelerde mevcut yöntemlerle boy uzunluğunu doğnı olaıak hesapladıklarını bildirdiler. Ayrıca, kimliği bilinmeyen kişlleıin boy uzunluğu ile ilgili kaynıann değerlendirilmesi yapıldığında, bu bireylerin çoğunun boy uzunluklarının kayıtlara işlenmemiş olduğunu gördük. Ekstremhe kemiklerinin yardımıyla boy uzunluğu hesaplanmasının ve incelenen kemiklerin aıt olduğu kişilerin kimliklerinin sapıanması amacıyla kullanılmakta olan tekniklerin geliştirilmesinin, kayıtların yetersiz olduğu koşullarda imkansız olduğwıu vurguladık.
Summary
A review was conducted among members of ı1ıe American Academy of Forensİc Sciences, Phyııcal
Anthropology Section, to verify the accuracy of estimaıing statııre of individuals based upon mcomrlete long bones. Of those amhıopologisıs who had oppoııuııities lo vcrify the technique, 55% achieved accurate statuıe csLlmates. Further, an evaIuatian of records rcpoıting the stature of unknown individuals, indicates ı.ııal
aCcUfate stature records are not availahle for most individuals. 'This has madc it difficull to develop aCCUfaıe
tcchniqucs for estirnaıing Wilııee from limb bones, and 10 veriJy stalure e.sıimntes on ımknown individuak
Kc} ",ord s : lncomp/ete long boııes -Sıature esıimaıion - Reliabilily - Records
Adli Tıp Derg., 6, 167 170 (1990)
ADL
İ TIP DERGİSİ
Journal of Forensic Medicine
168 S. BROOKS. D.G. STEELE. ıur. BROOKS
Steele (1), Steele and MeKern (2) and Sıeele and Bramblett (3) developec! and revised a series of regression formulae making it possible to esLimate long bone Icngths and stature of humans from incomplete humeri, femora and libiae. Based on analyses of the
Terry Colleetion, Department of Anthropology, Smithsonian Institution, Washington, D.C., regression formulae were developed for specified segments of these long bones for males and females of American blacks and whites. The technique uLilizes specific seg-ments, demareated by anatomicallandmarks, of the epiphyses of the three bones. Inves-tigators wishing to estimate stature following the teehnique must recognize one or more of the demareated segments in the bone of the unknown individual, measure the segment or segments, and use this measurement in the appropriate regression formula [or esti
-mating long bone length. Af ter long bone length is reconstructed, then stature can be estimated from this reconstructed long bone length utilizing previously published
for-mulaeJor the estimation of stature, such as those developed by Trotter and Cleser (4,5)
for American blaeks and whites. Altematively, stature can be estimated directly utilizing
formulae provided by Steele (1) or Steele and Bramblett (3).
Usually, osteologists researehing prehistoric human remains do not atlempt to derive stature from incomplete skeletal elements, although those working with historic data may have information on an individual's antemortem stature and employ Sieele's
formulae for verification purposes. The most frequent use of this method of stallire reconstruction is in forensic physical anthropology, where it can aid idcntification of a person represented by incomplete long bones.
One signifieant aspect of forensic physical anthropology is the possibility that skeletal remains, examined in research, will be positively identiGed. These cases provide a testing of the applicability of various methods of skeletal analysis, as the determinations of age, sex, biological affinity and stature. The feedback results from identifieation provide the necessary evidence of the reliability of these techniques.
Brooks, utilizing one of Steele 's 1970 formulae (1) on a forensic case where all the long bones were incomplete, derived an estimate of stature which was c10se to the
identified person's stature. This led the authors to evaluate how frequcntly other researchers had used the technique, and how close their estimates were to the verificd stature of the deceased. Letters were sent to 62 members of the Physical Anthropology Section of the American Academy of Forensic Sciences asking if they had used the 1970 formulae (3) in their forensic case work and if, in their opinion, the technique could be verified as accurate or reliable. Specifically requested were cases where the stature estimate had proven reasonably near that of the subsequently identified individual. Twenty six responses (42% of the members) were received. Of these, 14 who responded (54%) had never had occasion to apply the formulae. Those who had cmployed the formu1ae did not always state if they used the 1970 formulae (1). The results were one (4%) who had no opportunity to verify the estimate, five (19%) whose verificd stature differed from the estimates provided by Steele's and collaboraıors' (2,3) method and
Fonnulae for Stature Estimation on Incomplete Long Bones 169
6 (23%) whose verified estimates were correct, or close to the actual stature. Thus, 55% of those who had opportunities to verify stature estimates based upon evaluation of incomplete long bones reported their estimates to be accurate. AIso included in the positive replies were comments on the value of the technique for differentiating remains of commingled individuals, and the value of the technique in assisting identifications by
providin~stature estimates which were not accurate but close to the true stature. Investİgators were also asked to state any problem s encountered utilizing the method. Most of those who responded to this request acknowledged difficulties in locating specific landmarks used to demarcate the segment identified by Steele and collaborators. Landmarks delineating the epiphyses of the long bones usually were considered recognizable, particuIarly those deseribing the segment of the proximal femur. Landmarks delineating diaphyseal segments of the distal end of the femur and tibia, and the Iandmark separating the diaphyseal segments of the humerus were found to be difficult to recognize. it should be noted that Steele and Bramblett (3) anticipated these difficulties conceming the humerus and reidentified segments for the humerus in this contribution.
The review of Steele's method has also raised other issues regarding the evaluation of stature estimates which should be addressed. These questions concem the accuracy of stature estimations of the reference sample and the unknown individual? How accurate were the stature estimates of the individuals in the Terry Collection used to establish the regression formulae for stature estimation? How was the stature of the unknown individual verified? Was it taken from a driver's license as in the U.S.? Willey and
Falsetti (6) have shown that stature records on these documents are commonly incorrect.
Did relatives supply the estimate stature of the unknown individual? Relatives' estimates may be similarly incorrect for theyare commonly based upon subjective criteria or hearsay, rather than accurate measurements. Was the stature estimate based upon arecem assessment of the individual's stature? This is important since an individual stature decreases during adult life (4,5). Were the stature estimates, even those made by institutions such as the military or other govemment agencies, made accurately and by trained technicians? Even Trotter and Cleser's formulae, the formulae most commonly used in the U.S., may not have been based on a sample whose living stature was accurately determined. As Trotter (7) pointed out, they were the results of measurements taken, probably not by trained personnel, when the men joined the service. Were stature estimates of the individuals utilized to develop the regression formulae based upon stature estimates taken during life, or were the measurements of the cadaver? Stature of individuals in the Terry Collection which Steele used to derive his formulae for estimating stature directly from incomplete long bones, was based upon cadaver length which must then be converted to living stature. Trotter (7) and
Trotter and Cleser (4) have documented that cadaver length is greater than living stature,
and propose d that the difference is between 2.35 cm. and 2.69 cm. with the average difference considered to be 2.5 cm. How accurate is this estimate of the ratio of living
170 S. BROOKS, D.G. STEELE, R.H. BROOKS
stature to cadaver length, and how much might it vary from cadaver sampk to eadavcr sample?
When questiüns such as these can be raised about the antemortem height of thc unknown deeeased individual and those comprising the comparatiye samplc, it is no surprise that stature results based upon ineomplete skeletal elements may nüt always bc aeeurate. From this viewpoint it is amazing that deri ve d stature from ineomplete long bones were sufficiently reliable that 23 % of Academy members, more than 50 % of those who had the opportunity to verify the technique, replied that they had aeeurate estimations of verified living stature.
Although age at death, sex and ethnicity can be documented easily, sametimes even birth certificates obtained, adult stature rarely has bcen aecurately recorded during life. At this time therc appears no easy solution to be problem of accuracy of stat.urc in li ving people who are not involved in same oceupatian where height is taken at periodie intervals by traüıed persünneL. it appears that this desire for accUfate estimates of staturc will remain the dream of farensic scientists for quite same time. (-ynscquently, estimations of stature, be they made from eomplcte of incomplete long bones, should be considered approximations only of the true stature of unknown individuals.
REFERENCES
Steele, D.G. (l' :0) in Personal ldenlificaıion in Mass Disaslers (Stewart, T.D., ed.), National Museurıı of Natural Hi'i(lfY, Smithsonian Institution, Washington, D.C.
2 Steele, D.G., . LKem, T.W. (1969) Am. J. Phys. Anlhropo!', 31,215-227.
3 Steele, D. G., E'ramblett, C. A. (J.988) The Ana/omy and Bio!ogy of the HUl7ILln Skeleıon, Texas. 1I-&M University Press, College Station, Texas.
4 Trotter, M., Gleser, G.c. (1952) Am. J. Phys. Anthropol., 10, 463-514.
5 Trotter, M., Gleser, G.c. (1958) Am. J. Phys. Anıhropol., 16,79-123.
6 Willey, P., Falsetli, T. (1987) The lnaccuracy of Height and Weighı Inforl7lLlıion on Driver Licenses, Presented at L'ıe 39th annual Meeling of the American Academy of Forensic Sciences, San Diego, Califomia.
7 Trener, M. cı 970) in Personal ldenıificaıion in Mass Disasters (Stewart, T.D., ed.), National Museum of Nataral History, Smithsonian Institution, Washington, D.C.
Reprints request to
Dr. Sheilagh Brooks Department of Anıhropology,
University of Nevada, Las Vegas, NV, 89154, USA Adli Tıp Dergisi 1990; 6(1-2): 167-170
