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N Lynnerup

Publications and source records attributed to N Lynnerup.

At least 19 recordsLinked to original sources
PubMed2005

An historical skull collection and its use in forensic odontology and anthropology.

The Institute of Forensic Medicine, Copenhagen, houses a collection of historical skulls of unclear origin, marked with a general geographic or "racial descriptor". Would these historical skulls be of any value for the forensic odontologist and anthropologist concerned with teaching and casework? We tried to clarify this question by recording non-metric dental traits and by performing craniometric analyses. A morphological and morphometric investigation of anatomical/dental traits in 80 adult skulls was performed. For each skull four non-metric dental traits using the ASU-System and three non-metric cranial traits were recorded. Nineteen cranial measures were also taken following the FORDISC programme manual. The non-metrical data were tabulated as frequencies, and the metric data were entered in the FORDISC programme. Observed non-metric trait frequencies were compared with published data. The FORDISC programme computed a discriminatory analysis for each skull and thereby assigned the skull to the most probable ethnic category. The results for the non-metric traits showed that the traits generally followed the expected frequencies in 80% of the cases. The FORDISC programme correctly assigned ethnicity based on skull measurements in overall 70% of the cases. It was found that this historical collection does show expected dental non-metric and craniometric traits and the collection may be of value in forensic casework in terms of comparison and for teaching purposes.

Adult↗
PubMed2004

The effect of calcium and vitamin D3 supplementation on the healing of the proximal humerus fracture: a randomized placebo-controlled study.

The purpose of this study was to (1) quantify the healing process of the human osteoporotic proximal humerus fracture (PHF) expressed in terms of callus formation over the fracture region using BMD scanning, and (2) quantify the impact of medical intervention with vitamin D3 and calcium on the healing process of the human osteoporotic fracture. The conservatively treated PHF was chosen in order to follow the genuine fracture healing without influence of osteosynthetic materials or casts. Thirty women (mean age = 78 years; range = 58-88) with a PHF, osteoporosis or osteopenia (based on a hip scan, WHO criteria), and not taking any drugs related to bone formation, including calcium or vitamin D supplementation, were randomly assigned to either oral 800 IU vitamin D3 plus 1 g calcium or placebo, in a double-blind prospective study. We measured biochemical, radiographic, and bone mineral density effect parameters to evaluate the impact on the healing process. Scanning procedures of the fractured shoulder included use of a fixation device to obtain the highest possible precision. Double scans of the fractured shoulder revealed a coefficient of variation (CV) on BMD measurements that improved from 2.8% immediately after fracture occurrence to 1.7% at 12 weeks (P = 0.003) approaching the 1.2% levels observed over the healthy shoulder. BMD was similar in the two groups at baseline (active 0.534 g/cm2 vs. placebo 0.518 g/cm2), and both increased over the 12-week observation period, with peak levels in week 6. By week 6 BMD levels were higher in the active group (0.623 g/cm2) compared with the placebo group (0.570 g/cm2, P = 0.006). Thirty seven percent of the patients presented with vitamin D levels below 30 nmol/l, indicative of mild vitamin D insufficiency. In conclusion, we have demonstrated that it is possible to quantify callus formation of the PHF with sufficiently high precision to demonstrate the positive influence of vitamin D3 and calcium over the first 6 weeks after fracture. Whether this results in more stable fractures, extends to other fracture types, or applies to other osteogenic bone agents such as bisphosphonates remains to be examined.

Absorptiometry, Photon↗
PubMed2002

Bone mineral density measurement over the shoulder region.

The purpose of this study was to (1). establish a method for measuring bone mineral density (BMD) over the shoulder region; (2). compare the relationship between shoulder BMD levels with hip BMD and body mass index (BMI); and (3). discuss the relevance of the shoulder scan as an early indicator of osteoporosis compared with hip scans, the latter representing a weight-bearing part of the skeleton. We developed a scanning procedure, including a shoulder fixation device, and determined the most appropriate software in order to establish a reference material with the highest possible precision. Duplicate scans of the dominant side shoulder on 80 healthy, non-osteoporotic Danish women revealed a coefficient of variation (CVSD) on BMD measurements of 1.7%, with no difference between young and old subjects. Shoulder BMD values were significantly lower than hip BMD values (P <0.00001). Both hip and shoulder values decreased with age (P <0.001). The difference between hip and shoulder BMD levels increased significantly with increased body mass index (BMI) (P <0.002). The positive relationship between the increased hip/shoulder BMD differential with BMI supports the conclusion that the shoulder is subject to the least relative influence of weight and stress loading because of migration of calcium to weight and stress-bearing areas. Since the effect of this migration could mask local osteoporotic bone loss, shoulder BMD measurement is likely to minimize false indicators of healthy bone in women with high BMI, and might therefore be a relevant early stage indicator of osteoporosis.

Absorptiometry, Photon↗
PubMed2001

Cranial thickness in relation to age, sex and general body build in a Danish forensic sample.

The cranial thickness was measured in 64 individuals (43 males, 21 females) autopsied at our institute. The thickness was measured by taking a biopsy with a trephine at four specific locations on the skull. Complete medical records and pathologic autopsy results were available. While none of the individuals had suffered from diseases affecting bone or bone metabolism as such, a large sub group consisted of individuals with a history of, and autopsy finds consistent with, chronic substance and alcohol abuse. There was no statistically significant difference in cranial thickness measures between this group and the rest of the material. Subsequent analyses failed to reveal any correlations between the cranial thickness and sex and age and height and weight of the individual. This is in accordance with most earlier studies, which likewise show no correlation, or only very faint trends, between cranial thickness and these parameters. This study, thus, adds to other studies showing that cranial thickness cannot be used in aging or sexing human remains. Likewise, in a forensic pathological setting, cranial thickness cannot be inferred from the individuals stature and build, which may be an issue in cases of interpersonal violence with cranial trauma.

Adolescent↗
PubMed2001

Mobile autopsy teams in the investigation of war crimes in Kosovo 1999.

On request of the International Criminal Tribunal for the former Yugoslavia (ICTY), the Danish-Swedish forensic teams worked in Kosovo during the summer and the fall of 1999. The teams worked mainly as "mobile teams" at sites with few graves. Only two larger sites were examined. Most of the bodies were buried separately. A few "multiple burial" graves were examined, but no mass graves were encountered. The main purpose of the autopsies was to establish the cause and manner of death. Identification was of less importance, but a majority of the bodies had been identified prior to the autopsy. A total of 308 bodies, mainly males, were examined. The age varied greatly with a mean age of 47 years. The most common cause of death was gun shot wounds and the most common manner of death was homicide.

Adolescent↗
PubMed2000

mtDNA variation among Greenland Eskimos: the edge of the Beringian expansion.

The Eskimo-Aleut language phylum is distributed from coastal Siberia across Alaska and Canada to Greenland and is well distinguished from the neighboring Na Dene languages. Genetically, however, the distinction between Na Dene and Eskimo-Aleut speakers is less clear. In order to improve the genetic characterization of Eskimos in general and Greenlanders in particular, we have sequenced hypervariable segment I (HVS-I) of the mitochondrial DNA (mtDNA) control region and typed relevant RFLP sites in the mtDNA of 82 Eskimos from Greenland. A comparison of our data with published sequences demonstrates major mtDNA types shared between Na Dene and Eskimo, indicating a common Beringian history within the Holocene. We further confirm the presence of an Eskimo-specific mtDNA subgroup characterized by nucleotide position 16265G within mtDNA group A2. This subgroup is found in all Eskimo groups analyzed so far and is estimated to have originated <3,000 years ago. A founder analysis of all Eskimo and Chukchi A2 types indicates that the Siberian and Greenland ancestral mtDNA pools separated around the time when the Neo-Eskimo culture emerged. The Greenland mtDNA types are a subset of the Alaskan mtDNA variation: they lack the groups D2 and D3 found in Siberia and Alaska and are exclusively A2 but at the same time lack the A2 root type. The data are in agreement with the view that the present Greenland Eskimos essentially descend from Alaskan Neo-Eskimos. European mtDNA types are absent in our Eskimo sample.

Alaska↗
PubMed1998

Intra- and inter-observer variation in histological criteria used in age at death determination based on femoral cortical bone.

The microscopic method of age at death determination was introduced by Kerley in 1965. The method, which relies on the quantification of selected elements in cortical bone tissue, has been widely used, and several other researchers have modified or added to the method. Yet, very few studies have been carried out dealing with the intra- and inter-observer error. Furthermore, when such studies have been completed, the statistical tools for assessing variability have not been adequate. This study presents the results of applying simple quantitative statistics on several counts of microscopic elements as observed on photographic images of cortical bone, in order to assess intra- and inter-observer error. Overall, substantial error was present at the level of identifying and counting secondary osteons, osteon fragments and Haversian canals. Only secondary osteons can be reliably identified, precluding the use of osteon fragments and Haversian canals. The observers in this study included experienced and inexperienced users of the microscopic method, yet the variability was uniformly large for all observers, suggesting fundamental problems in definition and identification of the structural elements. Until more rigorous definitions of such elements have been agreed upon, the use of microscopical methods must be discouraged as a sole or uncontrolled method of evaluating age at death.

Age Determination by Skeleton↗
PubMed1996

Estimation of otitis media in ancient populations. A study of past and present Greenlandic Inuit.

Examination of disease patterns in the past has often been difficult due to lack of morphological evidence. This study presents a new unbiased method for estimation of occurrence of infectious middle ear disease (IMED) in childhood. The method is based on the relation between IMED in childhood and small or asymmetric pneumatized cell areas in the temporal bones as seen on standardised X-rays. A polychotomous logistic regression model was applied on 434 pneumatized cell areas in temporal bones from 34 adult living Greenlandic Inuit, 56 adult crania from the 18th to the 19th century, A.D. and 127 adult Inuit crania from the pre-European colonization period (before A.D. 1721) of Greenland. The occurrence of IMED as designated by the model was eight out of 34 (23.5 per cent) in living Inuit, 10 out of 56 (17.9 per cent) in crania from the 18th to 19th century and six out of 127 (4.7 per cent) in crania from the pre-colonization period. These frequencies differed significantly (p < 0.002). The mean area size also differed significantly, thus indicating a change in occurrence of IMED and a decrease in area sizes from past to present in Greenland.

Adolescent↗
PubMed1995

Routine use of ultraviolet light in medicolegal examinations to evaluate stains and skin trauma.

The use of ultraviolet light induced fluorescence as an aid in forensic medical examinations of rape victims was evaluated preliminarily in a retrospective, non-consecutive study. In a four-month period, 17 cases were referred by the police for examinations at the Institute of Forensic Pathology. Ultraviolet light illumination (UVI) was used in seven cases, and in six cases fluorescent skin areas were observed. The fluorescence was due to lesions in four cases and stainings with saliva and semen in other two cases. In at least two cases, skin trauma detected with UVI were unobserved in ordinary light. It is concluded that UVI should be a routine part of forensic medical examinations. It may assist the forensic medical examiner in finding skin trauma and in locating stains, thus enabling retrieval of material for serological analyses. UVI is simple to carry out, requiring only a small, portable ultraviolet light source.

Aged↗
PubMed1995

Pneumatization and otitis media in Greenlandic Inuit before European colonization.

A total of 127 Greenlandic Inuit crania from before the European colonization of Greenland and deriving from the West (W), Southeast (SE), and Northeast (NE) coast of Greenland were examined for sequelae of infectious middle ear disease (IMED) and for a relationship between the size of the pneumatized cell area in the temporal bones and cranial morphology. IMED was inferred from the area size of the pneumatized cell system as seen on x-rays. The crania were classified into IMED or non-IMED by applying a statistical model on the distribution of areas. The model designated six crania (4.7%, 95% CI: 1.8-10.0%) as having had IMED, four from the W, one from the SE, and one from the NE. This is lower than the present frequency of IMED in Greenland. One cranium revealed pathology resembling that caused by chronic inflammation (e.g., from cholesteatoma or cancer). The area sizes differed significantly between sexes and between regions, as did some of the cranial measures. This indicated a relationship between cranial morphology and the area size. However, in a multiple regression analysis, cranial morphology only explained 5 to 7% (R2) of the variability in the areas.

Archaeology↗
PubMed1994

Statistical model estimating the occurrence of otitis media from temporal bone pneumatization.

In order to investigate the relationship between the pneumatization of temporal bones and the occurrence of otitis media in Greenlandic Inuit, 36 Greenlandic Inuit were examined by radiography of the temporal bones. The pneumatized cell area was measured planimetrically. All subjects answered a questionnaire on infectious middle ear disease (IMED), and an objective otologic examination was performed. Nine persons of 34 (26%) reported IMED in childhood, and there was IMED reported in all pneumatized areas below 400 mm2. Based on bilateral area measures, a polychotomous logistic regression model was applied. The occurrence of IMED was shown to be associated with smaller areas, and unilateral IMED was associated with pronounced asymmetry. The model has enabled risk assessment, and 8 persons were designated by the model as having had IMED with a sensitivity of 67% (confidence interval 30% to 93%) and a specificity of 92% (confidence interval 74% to 99%). When the model was applied to a historical anthropological Inuit material from 1700 to 1800 AD, 6 of 56 crania were designated as having had IMED. This method has improved the accuracy of estimating the occurrence of IMED in ancient populations.

Adolescent↗
PubMed1993

Automatic data acquisition of anthropological measurements.

A computer program in BASIC is presented which enables the input of measurement data from a caliper directly into specific records in a dBASE IV or PARADOX database. The program circumvents the tedious procedure of first recording measurement data manually and then entering the data into a computer. Thus much time can be saved and the risk of wrong data entry is lowered. The program was easy to use, and no significant problems were encountered. Necessary hardware is a standard IBM compatible desktop computer, Mitotoyu Digimatic (TM) calipers and a Mitotoyu Digimatic MUX-10 Multiplexer (TM).

Anthropology, Physical↗