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ABSTRACT: Shear load sharing between intervertebral discs and apophyseal joints was investigated experimentally in human lumbar motion segments with moderately degenerated intervertebral discs. 'Motion-Segments' (21-42 years, n=6) and 'Disc-Segments' (22-42 years, n=6) were subjected to shear in 0° flexion, using a modified materials testing machine, while immersed in a Ringer bath at 37°C. Initially, two cycles of anterior and posterior shear loading up to 200N (50N/s) were applied, to evaluate stiffnesses in both directions. Specimens were then exposed to 15mm of anterior displacement at a rate of 0.5mm/s. A physiological compressive load of 500N was applied throughout. The initial 5mm of the load-displacement curves were approximated with 6th order polynomials for evaluation of the mean behaviour in each group. 'Disc-Segments' were 66% (p=0.002) and 43% (p=0.026) less stiff than 'Motion-Segments' for anterior and posterior shear directions, respectively. 'Disc-Segments' exhibited 44% lower peak shear load (p=0.015) than 'Motion-Segments'. All specimens in the 'Disc-Segments' group showed damage either at the interface between the endplates and the disc. The intervertebral disc contributes 38% to initial anterior shear load-bearing, increasing to 66% at 5mm displacement. Some over-estimation of disc load-bearing might have been caused by the comparison of segments from different levels. The apophyseal joints make a substantial contribution (65-55%) to anterior shear load-bearing over the initial 2mm of shear displacement but this decreases with increasing shear displacement.
Journal of biomechanics 01/2013; · 2.66 Impact Factor
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ABSTRACT: Through qualitative interviews with six female survivors of intimate partner violence (IPV) in Germany, we explored their experiences with health and health care within the context of a universal access health system. Using phenomenological analysis, we learned that they view violence as a burden on health; expect health professionals to acknowledge the link between IPV and health with empathy; and experience barriers to acute mental health services despite a lack of financial barriers in seeking treatment. We discuss how our findings compare with other international research, as well as the implications for the health care system's response to IPV.
Health Care For Women International 11/2012; · 0.63 Impact Factor
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ABSTRACT: Loosening of the tibial tray is cited as the most common cause of failure in total knee arthroplasty but the mechanism remains unclear. Post mortem specimens provide a unique opportunity to investigate the clinical condition.
Twenty two cemented components were serially retrieved in situ at autopsy from a university clinic. They were investigated for mechanical stability by pull-out, which was related to cement morphology and bone quality from CT scans, and to polyethylene wear by score analysis. Implants were grouped into three types: a particular fixed bearing design (n=8), a particular rotating platform design (n=5) and other mixed designs (n=9).
Trends were observed for pull-out force to decrease with time in situ and increase with cement penetration but was unrelated to bone density or polyethylene wear. For the fixed bearing implants decreasing pull-out strength was related to an increasing proportion of failure at the bone-cement interface. For the mixed designs the opposite was observed. The rotating platform implants failed at the implant-cement interface.
The analysis demonstrated that interface failure is dependent on the implant design, but that both the stem and the bone interfaces weaken with time in situ. Published findings for laboratory implantations have demonstrated that greater cement penetration improves fixation and this was reflected for clinical samples in this study.
Clinical biomechanics (Bristol, Avon) 07/2012; 27(9):929-35. · 1.76 Impact Factor
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ABSTRACT: Shear loading is recognised as a risk factor for lower back pain. Previous studies of shear loading have either not addressed the influence of age, bone mineral density, axial height loss due to creep or were performed on animal specimens.
Intact human lumbar motion segments (L2-3) were tested in shear using a modified materials testing machine, while immersed in a Ringer bath at 37°C. Vertebrae were rigidly embedded in neutral posture (0° flexion) and subjected to a constant axial compression load of 500 N. Shear was applied to three groups: 'Young-No-Creep' (20-42 years), 'Young-Creep' (22-38 years, creep 1000 N for 1h) and 'Old-No-Creep' (44-64 years). Failure was induced by up to 15 mm of anterior shear displacement at a rate of 0.5mm/s. The trabecular and apophyseal joint bone mineral densities were evaluated from computed tomography images of the intact lumbar spines.
Peak shear force correlated positively with trabecular bone mineral density for specimens tested without axial creep. No significant differences were observed with respect to age. During shear overload specimens increased in height in the axial direction.
Trabecular bone mineral density can be used to predict the peak force of lumbar spine in shear in neutral posture.
Clinical biomechanics (Bristol, Avon) 05/2012; 27(7):646-51. · 1.76 Impact Factor
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ABSTRACT: A 34-year-old heroin addict in the eighth month of pregnancy was found dead in her apartment. The head of a fetus was partly
protruding from underneath the woman’s slip. At the time of autopsy, the body was in a state of advanced putrefaction with
greenish discoloration of almost the complete body surface showing pronounced marbling and, in addition, now not only the
head but also the upper part of the chest of a dead fetus were extruding from the birth canal with head presentation. Autopsy
showed no signs of external violence prior to death and, in particular, no indication of preceding manipulations in the region
of the obstetrical canal and the uterus could be detected. The uterine cavity showed pronounced putrefactive alterations with
the amniotic membranes being partially raised and bloated in a balloon-like fashion. Toxicological analyses revealed acute
heroin intoxication of mother and child. The immature neonate showed no signs of live birth. Pathogenetically, the finding
of not only the head but also the upper part of the chest of the fetus extruding from the birth canal at the time of autopsy
(contrary to the observation made at the death scene that only part of the head of the fetus was protruding) is consistent
with post-mortem fetal extrusion caused by putrefactive gas pressure against the pregnant uterus as reported in the earlier
German forensic pathological literature.
Forensic Science Medicine and Pathology 04/2012; 1(4):273-276. · 1.44 Impact Factor
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ABSTRACT: The mechanically stimulated idiomuscular contraction of skeletal muscles is part of the widely used compound method for death time estimation and therefore represents an item of high relevance and practicability in forensic case work. However, data on the topic are scarce and inconsistent and the currently reported maximum time span for the occurrence of the phenomenon until 13 h post-mortem (hpm) is based on a single case report from the beginning of the twentieth century. Therefore, idiomuscular contraction following mechanical stimulation has been investigated in skeletal muscles of 270 cases with assured time of death at defined post-mortem time points between 7 and 15 hpm. Of all investigated cases, 45 (16.7%) showed a positive reaction with a preponderance of cases of sudden death. Our investigations confirmed the upper time limit of 13 hpm up until idiomuscular contraction could be stimulated. With every hour of the post-mortem interval, a 0.61-fold decrease of the phenomenon's occurrence was observed (95%CI, 0.52-0.72; p < 0.001). Furthermore, several parameters showed significant correlations with the likelihood of the phenomenon's occurrence, namely stimulation of upper arm as opposed to the thigh (p < 0.001), gender (p = 0.017), and BMI (p < 0.001). These findings for the first time give reliable evidence of a post-mortem time limit of mechanically stimulated idiomuscular contraction and therefore contribute to the future application of the method in forensic case work.
Deutsche Zeitschrift für die Gesamte Gerichtliche Medizin 01/2012; 126(3):399-405. · 2.59 Impact Factor
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ABSTRACT: We describe and discuss haemorrhages discovered in the back and auxiliary breathing muscles of a population of cases of suicidal death by hanging. Intramuscular haemorrhages were present in approximately 30% of the cases. Pre-existing illnesses with an increased tendency to bleed or an anticoagulant medication did not exist; corresponding skin and subcutaneous fatty tissue structures were intact in each case. In cases of death by hanging, the occurrence of muscle haemorrhages of this type may be explained pathophysiologically by the occurrence of increased respiratory exertions and/or seizures during the hanging process. Although the results of our study do not indicate an obligatory autopsy finding, evidence of internal haemorrhaging into the back and auxiliary breathing muscles may be called upon following consideration of differential diagnostic aspects as a further diagnostic indication of vital hanging.
Deutsche Zeitschrift für die Gesamte Gerichtliche Medizin 09/2011; 125(6):863-71. · 2.59 Impact Factor
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ABSTRACT: Two cases of sudden and unexpected death due to necrotizing fasciitis are presented with a short overview of this rare disease with special reference to pathological features and causative and epidemiological factors. One case occurred as a complication of liposuction surgery, and the second presented after minor trauma. Based on the autopsy findings and an interdisciplinary approach, medico-legal evaluation provides a substantial basis for later court hearings in such cases.
Forensic Science Medicine and Pathology 09/2011; 7(3):278-82. · 1.44 Impact Factor
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ABSTRACT: To analyze horse-related accidents caused by hoof kicks.
Prospective study to evaluate hoof kick-related accidents.
Multicenter study, including 9 trauma centers in Hamburg, Germany.
Patients who were treated as the result of a hoof kick between January 1, 2010, and May 1, 2010, were included in the study.
Horse and rider qualifications, riders' use of protective equipment, location and activity at time of accident, mechanism of injury, injuries sustained, and treatment required for these injuries.
Twenty-four equestrians received hoof kicks. The average age was 22.6 years (range, 7-34 years). All accidents (100%) occurred while the equestrians were handing or grooming the horse. Two riders (8.3%) wore a helmet at time of accident. Sixteen riders (66.7%) suffered orbital, midface, or mandible fractures; 8 riders (33.3%) had injuries on other parts of the body.
Hoof kick injuries account for a significant proportion of equine injuries and occur when riders are dismounted, most frequently when grooming without wearing protective equipment. Head and facial injuries occur most frequently and suggest that mandatory helmet and facial grill use should be considered during all horse-related activities.
Clinical journal of sport medicine: official journal of the Canadian Academy of Sport Medicine 06/2011; 21(4):353-5. · 1.50 Impact Factor
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ABSTRACT: The purpose of this study was to describe a simplified arytenoid rotation technique and to test its applicability in excised human larynges. A non-absorbable monofilament thread is slung around the muscular process of the arytenoid cartilage through an external approach. During visual control through flexible endoscopy, two needles and a wire loop needle threader are the only instruments needed. Thread tensioning and fixation results in a stabilized arytenoid adduction. This technique avoids cricothyroid joint disarticulation and leaves the thyroid cartilage intact. The practicability of the technique was proven in five excised larynx experiments. In two clinical cases, the muscular process was slung and pulled with a monofilament thread. Tension in the vector direction parallel to the LCA muscle showed an effective and stable arytenoid rotation with complete closure of the posterior glottis. The rotational effect following sling arytenoid adduction (SAA) is similar to conventional arytenoid adduction surgery outcome. However, SAA is performed from an external approach and avoids dissection of cartilage. Challenging dissections to reach the muscular process are avoided. In some cases of unilateral vocal fold immobility, arytenoid rotation may be performed by using the SAA technique, which allows for an external and extralaryngeal approach. Further studies should assess the clinical value of this technique. In principal, the wire loop needle threader can also be employed for external vocal fold lateralization procedures.
Archives of Oto-Rhino-Laryngology 03/2011; 268(7):1023-8. · 1.29 Impact Factor
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Juliane Hannemann,
Sönke Meyer-Staeckling,
Dirk Kemming,
Iris Alpers,
Simon A Joosse,
Heike Pospisil,
Stefan Kurtz,
Jennifer Görndt, Klaus Püschel,
Sabine Riethdorf,
Klaus Pantel,
Burkhard Brandt
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ABSTRACT: During cancer progression, specific genomic aberrations arise that can determine the scope of the disease and can be used as predictive or prognostic markers. The detection of specific gene amplifications or deletions in single blood-borne or disseminated tumour cells that may give rise to the development of metastases is of great clinical interest but technically challenging. In this study, we present a method for quantitative high-resolution genomic analysis of single cells. Cells were isolated under permanent microscopic control followed by high-fidelity whole genome amplification and subsequent analyses by fine tiling array-CGH and qPCR. The assay was applied to single breast cancer cells to analyze the chromosomal region centred by the therapeutical relevant EGFR gene. This method allows precise quantitative analysis of copy number variations in single cell diagnostics.
PLoS ONE 01/2011; 6(11):e26362. · 4.09 Impact Factor
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ABSTRACT: We describe and discuss autopsy findings of bowel wall hemorrhage in a study population comprising cases of suicidal death by hanging. Intramural hemorrhages were seen in approximately 12% of the cases examined; no preexisting bowel diseases were found. In hanging deaths with a longer agonal phase, we opine that abdominal congestion during the hanging process provides a viable pathophysiological explanation for bowel wall hemorrhage. Though we are not dealing here with obligatory autopsy findings, the detection of bowel wall hemorrhage might be used as another sign of vital hanging after considering differential diagnostic aspects.
Deutsche Zeitschrift für die Gesamte Gerichtliche Medizin 01/2011; 125(3):403-10. · 2.59 Impact Factor
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ABSTRACT: Pulsatile lavage is purported to improve radiographic survival in cemented total knee arthroplasty (TKA). Similarly, a potential improvement of fixation strength of the tibial tray has been assumed based on the increased cement penetration. In this study, the influence of pulsed lavage on fixation strength of the tibial component and bone cement penetration was evaluated in six pairs of cadaveric specimens. Following surgical preparation, the tibial surface was irrigated using pulsatile lavage on one side of a pair, while on the other side syringe lavage was applied. All tibial components were implanted using the same cementing technique. Cement penetration and bone mineral density was assessed based on computed tomography data. Fixation strength of the tibial trays was determined by a pull-out test with a material testing machine. Median pull-out forces and cement penetration were significantly (p = 0.031) improved in the pulsed lavage group as compared to the syringe lavage group. Enhanced fixation strength is suggested as being a key to improved survival of the implant. Consequently, pulsatile lavage should be considered as a mandatory preparation step when cementing tibial components in TKA.
International Orthopaedics 10/2010; 35(8):1165-9. · 2.03 Impact Factor
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ABSTRACT: Cell-based technologies for the repair of cartilage defects usually rely on the expansion of low numbers of chondrocytes isolated from biopsies of healthy cartilage. Proliferating chondrocytes are known to undergo dedifferentiation characterized by downregulation of collagen type II and proteoglycan production, and by upregulation of collagen type I synthesis. Re-expression of cartilage specific matrix components by expanded chondrocytes is therefore critical for successful cartilage repair.
Human articular chondrocytes were expanded on microcarriers Cytodex 3. The growth area was increased by adding empty microcarriers. Added microcarriers were colonized by bead-to-bead transfer of the cells. The chondrocytes were harvested from the microcarriers and characterized by their ability to synthesize collagen type II when cultivated in alginate beads using chondrogenic growth factors. A semi-automatic image analysis technique was developed to determine the fractions of collagen type II and type I positive cells.
The expansion of human articular chondrocytes on microcarriers yielded high cell numbers and propagation rates compared to chondrocytes expanded in flask culture for one passage. The proportion of collagen type II positive cells compared to collagen type I synthesizing cells was increased compared to chondrocytes expanded using conventional methods. The matrix synthesis upon treatment with chondrogenic factors IGF-I and BMP-7 was enhanced whereas TGF-ss had an inhibitory effect on microcarrier expanded chondrocytes.
Expanding human articular chondrocytes on microcarriers omitting subcultivation steps leads to superior ratios of collagen type II to type I forming cells compared to the expansion in conventional monolayer culture.
The International journal of artificial organs 04/2010; 33(4):204-18. · 1.86 Impact Factor
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ABSTRACT: Vibrations have been shown to be an important risk factor for spinal pathologies. The underlying mechanisms are poorly understood and in vivo data scarce and difficult to obtain. Consequently numerical models are used to estimate spinal loading; requiring fatigue strength information, which was obtained in this study for spinal specimens from young and old male donors of working age in vitro. Bone mineral density (BMD) and endplate area were determined using CT scans. Three groups were investigated: young specimens in neutral posture, young in flexed posture, and old in neutral posture. The loading consisted of 300,000 sinusoidal compression cycles of 2 kN, inducing a nucleus pressure peek of approximately 1.4 MPa. No failure of the young specimens in neutral posture was observed, but four specimens from older donors with low BMD failed. The product between endplate area and BMD was shown to be useful to predict fatigue strength for old donors and should therefore be considered with regard to whole body vibration injuries. In flexed posture, two specimens from young donors failed. One failure can be attributed to low BMD following the trend for the old specimens; the other failure could not be explained, leaving the influence of flexion yet unclear.
Industrial Health 01/2010; 48(5):550-6. · 0.94 Impact Factor
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ABSTRACT: Subdural bleeding (SDB) in infants is considered an essential symptom of nonaccidental head injury (NAHI). Recently, this view has been challenged by the "unified hypothesis," which claims that SDB in infants is related to hypoxia and brain swelling rather than to traumatic shearing of bridging veins. We analyzed a large series of infants' autopsies for the presence and causes of SDB, which should be a common event according to the unified hypothesis.
Autopsy, clinical, and legal information for infants <1 year of age from a single institution over 50 years were analyzed regarding cause of death, presence, morphology, and cause of SDB, and brain weight.
From a total of 16 661 autopsies during the study period, 715 (4.3%) involved infants <1 year of age. Fifty (7.0%) of those had SDB. NAHI was identified in 17 patients. The most common cause of SDB was trauma (15 cases [30.0%]), with NAHI accounting for 14 cases. SDB was present in 82.4% of patients with NAHI but only 5.2% of infants with other causes of death. Four patients (8.0%) had unexplained SDB with no discernible cause of bleeding. Statistical analysis did not reveal any correlation between the presence of SDB and brain weight.
In the study population, unexplained SDB in infants was an extreme rarity. Moreover, a correlation between brain swelling and the presence of SDB could not be drawn. Our data argue strongly against the unified hypothesis and strengthen the association between SDB and NAHI in infancy.
PEDIATRICS 12/2009; 124(6):1587-94. · 4.47 Impact Factor
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ABSTRACT: In consequence of the European guidelines of safety and quality standards for the donation, retrieval, storing and distribution of human tissues and cells the purpose of tissue transplantation was implemented into German legislation in May 2007. The law came into effect on August 1st 2007 considering of the European rules. The Institutes for Legal Medicine of the University of Frankfurt/Main and the University Medical Center Hamburg-Eppendorf developed a model for tissue retrieval. The Institute of Legal Medicine (I.f.R.) at the University Medical Center Hamburg cooperates with the German Institute of Cell and Tissue Replacement (Deutsches Institut für Zell--und Gewebeersatz DIZG). Potential post-mortem tissue donors (PMTD) among the deceased are selected by standardized sets of defined criteria. The procedure is guided by the intended exclusion criteria of the tissue regulation draft (German Transplant Law TPG GewV) in accordance with the European Guideline (2006/17/EC). Following the identification of the donor and subsequent removal of tissue, the retrieved samples were sent to the DIZG, a non-profit tissue bank according to the tissue regulation. Here the final processing into transplantable tissue grafts takes place, which then results in the allocation of tissue to hospitals in Germany and other European countries. The Center of Legal Medicine at the Johann Wolfgang Goethe-University Medical Center Frankfurt/Main cooperates since 2000 with Tutogen, a pharmaceutical company. Harvesting of musculoskeletal tissues follows corresponding regulations. To verify the outcome of PMTD at the I.f.R. Hamburg, two-statistic analysis over 12 and 4 months have been implemented. Our results have shown an increasing number of potential appropriate PMTD within the second inquiry interval but a relatively small and unvaryingly rate of successful post-mortem tissue retrievals similar to the first examination period. Thus, the aim of the model developed by the I.f.R. is to increase the number of PMTD retrievals and, furthermore, to avoid any conflict of interest between organ and tissue donation.
Forensic Science Medicine and Pathology 11/2009; 6(1):3-8. · 1.44 Impact Factor
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ABSTRACT: Up to 22 % of all child maltreatment cases involve non-accidental burns or scalds. In the time period of 2000 until 2007, 20 children with non-accidental burns and scalds in conjunction with other mechanisms of injury were examined at children's hospitals in Hamburg and at the Institute of Legal Medicine, University Medical Center Hamburg-Eppendorf, by experts in forensic medicine. The fact that these children presented with additional injuries due to blunt and sharp force and sometimes had signs of neglect emphasize the urgent need for a multidisciplinary cooperation between pediatricians and forensic medical experts to ensure the early identification and prevention of child maltreatment. A new approach for Germany, enforcing mandatory child well-being examinations is discussed.
Deutsche Zeitschrift für die Gesamte Gerichtliche Medizin 05/2009; 124(1):49-54. · 2.59 Impact Factor
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ABSTRACT: A case of a 24-year-old woman who gave birth to a mature newborn is reported. Many injuries at the head, neck and shoulders, back, mouth and throat which at least partly indicated unassisted childbirth were observed during autopsy. Some injuries, especially the different scull fractures were discussed controversially on trial. One expert postulated a coaction of unassisted childbirth and blunt head trauma to be responsible for the exitus. The other expert considered it possible that all injuries could originate from unassisted childbirth. The court consented to the opinion that all injuries could be the consequence of unassisted childbirth and the woman was exculpated from the accusation of manslaughter.
Legal Medicine 04/2009; 11 Suppl 1:S174-5.
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ABSTRACT: Captive-bolt guns or slaughterer's guns are devices widely used in meat industry and private farmer households for slaughtering animal stocks. They consist of a simple cylindrical metal tube (barrel) with a metal bolt placed in their centre (around 9-15cm long and 1-1.5cm wide). The bolt is actuated by a trigger pull and is propelled forward by compressed air or by the discharge of a blank powder gun cartridge. Violent deaths inflicted by captive-bolt guns are rarely encountered in forensic practice and are predominantly suicidal events. We report an unusual complex suicide by hanging and self-shooting with a slaughterer's gun in a 21-year-old boy. The victim after putting a ceiling fixed rope around his neck shot himself in the head (occipital region) with a Kerner captive-bolt gun. He used two mirrors (a cosmetic mirror and a man-sized one) in order to properly visualize his back and to target the occipital region of his head. Radiological data (computed tomography with three dimensional reconstruction) and autopsy findings are discussed according to the clinical and forensic literature. A brief review on planned complex suicides is also given.
Forensic science international 04/2009; 187(1-3):e7-11. · 2.10 Impact Factor
