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Camarini C, Teixeira LCL, Takeshita WM, Tolentino ES, Silva MC. Comparison of different methods of analysis of maxillary sinus volume and validation of a new proposal using cone beam computed tomography. J Forensic Leg Med 2023; 100:102611. [PMID: 37949005 DOI: 10.1016/j.jflm.2023.102611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 10/04/2023] [Accepted: 11/02/2023] [Indexed: 11/12/2023]
Abstract
PURPOSE develop and validate a formula, through a discriminant analysis of sex estimation, evaluating maxillary sinus in cone beam computed tomography scans in a Brazilian population, comparing this formula with two other existing ones. METHODS 190 cone beam CT scans of Brazilian adults were retrospectively evaluated by an independent examiner. Measurements were performed in the right and left MS region: height, width, length, distance between the breasts, distance between infraorbital foramina, and volume in the ITK software. The sample was divided into female and male. T test, ANOVA, Tukey test and the ROC Curve was performed (p > 0,05). RESULTS statistically significant differences were found in relation to the maximum height of the MS both right (p = 0,001) and left (p = 0,026) between sexes and the maximum length in the right MS (p = 0,01). Regarding the comparison of MS volume according to the different analysis methods, statistically significant differences were found between sexes for the right MS when using the method by Bangi et al. (p = 0,012) and the volume of the left MS in females (p < 0,001). Comparing the three classification models, statistically significant differences were found between the proposed method and the classification by Bangi et al. (p < 0.007). The ROC curve showed greater accuracy in the classification proposed in this work. CONCLUSION the new proposed formula obtained better predictions of sexual dimorphism, when compared to classifications already described in the literature.
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Affiliation(s)
- Camila Camarini
- Dentistry Department, Maringá State University, Maringá, PR, Brazil.
| | | | | | - Elen S Tolentino
- Dentistry Department, Maringá State University, Maringá, PR, Brazil
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Abdulai AR, Banyeh M, Adams Y. Models for estimating age and sex from variables of the proximal femur in a Ghanaian population. FORENSIC SCIENCE INTERNATIONAL: REPORTS 2022. [DOI: 10.1016/j.fsir.2022.100270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Faress F, Ameri M, Azizi H, Saboori Shekofte H, Hosseini R. Gender determination in adults using calcaneal diameters from lateral foot X-ray images in the Iranian population. Med J Islam Repub Iran 2021; 35:76. [PMID: 34291000 PMCID: PMC8285554 DOI: 10.47176/mjiri.35.76] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Indexed: 11/09/2022] Open
Abstract
Background: Using morphologic features of the bones is the basis of gender determination in anthropology and forensic medicine. In this study, we evaluated the calcaneus diameters for gender determination in the Iranian population.
Methods: This cross-sectional study was conducted on Iranians referring to Hazrat-e Rasool Hospital’s radiology ward for plain lateral X-ray of the foot. Lateral foot X-rays from 100 men and 100 women were gathered and evaluated for calcaneal indexes. These patients aged between 18 and 80 years old who did not suffer major trauma to the calcaneus bone were recruited. Using a picture archiving and communication system (PACS), four variables were calculated for each X-ray graph: Maximum anterior-posterior length of the calcaneus (MAXL), Maximum height of the bone (MAXH), Height of the cuboid facet (CFH) and Height the calcaneal body (BH). Cut off points for each index were calculated using the area under curve (AUC) in ROC curves.
Results: Lateral foot X-rays from 100 men and 100 women were gathered and evaluated for calcaneal indexes. The means of the four indexes were compared between the sexes which showed all four means are significantly different p value <0.001. AUC for MAXL in differentiating the genders was 0.824, which showed 86.8 as the cut off with a sensitivity of 80% and specificity of 69.0%. Cut off point for MAXH was set at 59.8 with sensitivity and specificity of 78.0% and 60.0%, respectively. For BH, 49.5 was set as the cut off point with a sensitivity of 79.0% and specificity of 64.0%. The best cut off point for CFH was 27.8 with 76.0% sensitivity and 63.0% specificity.
Conclusion: It can be concluded that the calcaneal diameters are reliable criteria for sex determination. Although the cutoff points are different between various races and populations, it is evident that these diameters can be used for sex determination in general.
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Affiliation(s)
- Foroozan Faress
- Department of Legal Medicine & Toxicology,Iran University of Medical Sciences, Tehran, Iran
| | - Maryam Ameri
- Department of Legal Medicine & Toxicology,Iran University of Medical Sciences, Tehran, Iran
| | - Hanieh Azizi
- Department of Legal Medicine & Toxicology,Iran University of Medical Sciences, Tehran, Iran
| | | | - Rozita Hosseini
- Department of Nephrology, Iran University of Medical Sciences, Tehran, Iran
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Carvallo D, Retamal R. Sex estimation using the proximal end of the femur on a modern Chilean sample. FORENSIC SCIENCE INTERNATIONAL: REPORTS 2020. [DOI: 10.1016/j.fsir.2020.100077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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Subasi O, Aslan L, Demirhan M, Seyahi A, Lazoglu I. A novel lower bound for tip-apex distance. Eur J Trauma Emerg Surg 2020; 48:1787-1798. [PMID: 33037920 DOI: 10.1007/s00068-020-01514-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 09/25/2020] [Indexed: 11/24/2022]
Abstract
PURPOSE The cut-out of the cephalomedullary nail is among the most common post-surgery complications for intertrochanteric fractures. As a risk predictor, a tip-apex distance (TAD) below 25 mm, observed from orthogonal fluoroscopic views, is recommended in the literature. This study aims to demonstrate that TAD < 25 mm is a mathematically insufficient risk definition and to complement the TAD upper bound with an appropriate lower bound, with the introduction of a novel distance parameter, TADX, based on the orthogonal projection of the nail tip on the central femoral midline. METHOD Through a mathematical simulation software, all the possible points that lie inside the AP and lateral views of the proximal femoral hemisphere are utilized to create a 3D grid that is sorted into geometrically safe and risk-bearing regions. Extending this methodology, TAD < 25 mm, 10 mm < TAD < 25 mm, and the ideal tip position volumes are simulated. Finally, intersection volumes are created by a combination of different candidate lower TADX bounds and TAD < 25 mm upper bound to determine satisfactory TADX limits. RESULTS Simulation of TAD-bound zones exposed that TAD is only a mathematically suitable parameter for defining the upper boundary but not the lower boundary for the optimal region. However, using a TADX lower limit creates a 3D volume that is much closer to the optimal tip region volumetrically and can still be as quickly calculated from 2D AP and lateral views. CONCLUSIONS According to the mathematical simulations, the use of a TADX lower bound of 9 mm for small, 7.5 mm for medium, and 7 mm for large femoral heads in conjunction with a TAD upper bound of 25 mm is suggested.
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Affiliation(s)
- Omer Subasi
- Manufacturing and Automation Research Center, Koc University, Istanbul, 34450, Turkey
| | - Lercan Aslan
- Department of Orthopaedics and Traumatology, Koc University Hospital, Istanbul, 34365, Turkey
| | - Mehmet Demirhan
- Department of Orthopaedics and Traumatology, Koc University Hospital, Istanbul, 34365, Turkey
| | - Aksel Seyahi
- Department of Orthopaedics and Traumatology, Koc University Hospital, Istanbul, 34365, Turkey
| | - Ismail Lazoglu
- Manufacturing and Automation Research Center, Koc University, Istanbul, 34450, Turkey.
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Cuzzullin MC, Curate F, Freire AR, Costa ST, Prado FB, Daruge Junior E, Cunha E, Rossi AC. Validation of anthropological measures of the human femur for sex estimation in Brazilians. AUST J FORENSIC SCI 2020. [DOI: 10.1080/00450618.2020.1729411] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
| | - Francisco Curate
- Research Centre for Anthropology and Health, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | | | | | | | | | - Eugénia Cunha
- Centre for Functional Ecology, Laboratory of Forensic Sciences, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
- Department of Life Sciences, National Institute of Legal Medicine and Forensic Sciences, Lisbon, Portugal
| | - Ana Cláudia Rossi
- Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, Brazil
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Fischer CS, Kühn JP, Völzke H, Ittermann T, Gümbel D, Kasch R, Haralambiev L, Laqua R, Hinz P, Lange J. The neck-shaft angle: an update on reference values and associated factors. Acta Orthop 2019; 91:53-57. [PMID: 31735107 PMCID: PMC7006743 DOI: 10.1080/17453674.2019.1690873] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Background and purpose - The neck-shaft angle (NSA) is valuable for diagnostics and therapy of the hip, but current reference values derive mostly from studies on anatomic specimens, small cohorts, or are hospital-based. Moreover, associated factors such as age, sex, or anthropometric data have rarely been considered. Therefore, we determined associated factors for NSA and reassessed the historical reference values in a general adult population.Methods - NSAs on both sides of 3,226 volunteers from the population-based Study of Health in Pomerania (SHIP) were measured with MRI. SHIP drew a representative sample of the population of Pomerania (northeastern Germany). NSAs were compared with sex, age, and anthropometric data by bivariable linear regression models. Reference values were assessed by quantile regressions for 2.5th and 97.5th percentiles.Results - The mean NSA was 127° (SD 7), while men had a lower NSA than women (95% confidence interval [CI] 0.4°-1.4°). The reference range was 114°-140°. Age was inversely associated with NSA (CI -0.2 to -0.1). Body height was positively associated with the NSA, while BMI and waist circumference showed a negative association. There was no association between body weight and NSA.Interpretation - The historical lower limit of 120° might be too high, so the radiological prevalence of hip pathology might have been overestimated. The previously reported influence of age, sex, and body height on the NSA has been confirmed.
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Affiliation(s)
- Cornelius S Fischer
- Clinic of Trauma, Reconstructive Surgery and Rehabilitation Medicine, University Medicine Greifswald, Greifswald;
| | - Jens-Peter Kühn
- Institute of Diagnostic Radiology and Neuroradiology, University Medicine Greifswald, Greifswald; ,Clinic and Policlinic of Radiology, University Hospital Dresden, Carl-Gustav-Carus University, Dresden, Germany
| | - Henry Völzke
- Institute for Community Medicine, Ernst-Moritz-Arndt University of Greifswald, Greifswald;
| | - Till Ittermann
- Institute for Community Medicine, Ernst-Moritz-Arndt University of Greifswald, Greifswald;
| | - Denis Gümbel
- Clinic of Trauma, Reconstructive Surgery and Rehabilitation Medicine, University Medicine Greifswald, Greifswald;
| | - Richard Kasch
- Center for Orthopedics, Trauma Surgery and Rehabilitation Medicine; Clinic and Outpatient Clinic for Orthopedics and Orthopedic Surgery, University Medicine Greifswald, Greifswald;
| | - Lyubomir Haralambiev
- Clinic of Trauma, Reconstructive Surgery and Rehabilitation Medicine, University Medicine Greifswald, Greifswald;
| | - René Laqua
- Department of Radiology, Städtisches Krankenhaus Kiel, Kiel;
| | - Peter Hinz
- Clinic of Trauma, Reconstructive Surgery and Rehabilitation Medicine, University Medicine Greifswald, Greifswald;
| | - Jörn Lange
- Clinic of Trauma, Reconstructive Surgery and Rehabilitation Medicine, University Medicine Greifswald, Greifswald; ,Correspondence:
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Curate F, Umbelino C, Perinha A, Nogueira C, Silva A, Cunha E. Sex determination from the femur in Portuguese populations with classical and machine-learning classifiers. J Forensic Leg Med 2017; 52:75-81. [DOI: 10.1016/j.jflm.2017.08.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 06/01/2017] [Accepted: 08/23/2017] [Indexed: 10/19/2022]
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9
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Akhlaghi M, Bakhtavar K, Kamali A, Maarefdoost J, Sheikhazadi A, Mousavi F, Saberi Anary SH, Sheikhazadi E. The diagnostic value of anthropometric indices of maxillary sinuses for sex determination using CT-scan images in Iranian adults: A cross-sectional study. J Forensic Leg Med 2017; 49:94-100. [PMID: 28614757 DOI: 10.1016/j.jflm.2017.05.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2016] [Revised: 02/26/2017] [Accepted: 05/24/2017] [Indexed: 10/19/2022]
Abstract
BACKGROUND The identification of human remains is an essential part of forensic science. Studying paranasal sinuses is very useful in identification of mutilated or burnt bodies from accidents such as plane crashes. We aimed to assess the diagnostic value of anthropometric indices of maxillary sinuses for sex determination using CT-scan images in Iranian adults. METHODS CT-scan slices of 228 maxillary sinuses (from 144 men and 144 women) were studied. The maximum height, maximum anterior-posterior diameter, maximum width, and maximum distance between the sinuses were measured in both sexes. Our participants were divided into three age groups of 20-34, 35-49, and over 50 to compare the recorded measurements in different age groups. RESULTS We found a significant difference between men and women regarding the maximum height, maximum width, maximum A-P diameter of sinuses and the maximum distance between the right and left maxillary sinuses in all of our participants. We also found that the highest accuracy for sex determination was related to the maximum distance between the sinuses (65.6%) and the lowest to the maximum width of the right sinus (56.2%). The most accurate identification resulted from assessing the maximum distance between the sinuses in the 20-34 age group (74.3%), the maximum anterior-posterior diameter of the sinuses in the 35-49 age group (62.8%) and the maximum height of the left sinus in the over 50 age group (65.7%). CONCLUSION Regardless of age, according to our study the parameters of height, width, anterior-posterior diameter of sinuses and the maximum distance between the right and left maxillary sinuses are partially valuable for sex determination. The most accurate sex identification was examined in the 20-34 age group from studying the maximum distance between the sinuses. Especially in the over 50 age group, it is not enough to consider the sinus parameter for sex identification.
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Affiliation(s)
- Mitra Akhlaghi
- Forensic Medicine Department, Faculty of Medicine, Tehran University of Medical Science, Tehran, Iran; Legal Medicine Organization of Iran, Tehran, Iran
| | - Khadijeh Bakhtavar
- Radiology Department, Faculty of Medicine, Tehran University of Medical Science, Tehran, Iran
| | - Artin Kamali
- Forensic Medicine Department, Faculty of Medicine, Tehran University of Medical Science, Tehran, Iran
| | - Jaleh Maarefdoost
- Forensic Medicine Department, Faculty of Medicine, Tehran University of Medical Science, Tehran, Iran
| | - Ardeshir Sheikhazadi
- Forensic Medicine Department, Faculty of Medicine, Tehran University of Medical Science, Tehran, Iran
| | - Farinaz Mousavi
- Forensic Medicine Department, Tehran University of Medical Science, Tehran, Iran.
| | - Seyed Hossein Saberi Anary
- Faculty of Health Management & Information Sciences, Kerman University of Medical Sciences, Kerman, Iran
| | - Elham Sheikhazadi
- Faculty of Nursing & Midwifery of Khorramabad, Lorestan University of Medical Sciences, Khorramabad, Iran
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Curate F, Albuquerque A, Ferreira I, Cunha E. Sex estimation with the total area of the proximal femur: A densitometric approach. Forensic Sci Int 2017; 275:110-116. [PMID: 28343024 DOI: 10.1016/j.forsciint.2017.02.035] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 02/21/2017] [Accepted: 02/28/2017] [Indexed: 11/19/2022]
Abstract
The estimation of sex is a central step to establish the biological profile of an anonymous skeletal individual. Imaging techniques, including bone densitometry, have been used to evaluate sex in remains incompletely skeletonized. In this paper, we present a technique for sex estimation using the total area (TA) of the proximal femur, a two-dimensional areal measurement determined through densitometry. TA was acquired from a training sample (112 females; 112 males) from the Coimbra Identified Skeletal Collection (University of Coimbra, Portugal). Logistic regression (LR), linear discriminant analysis (LDA), reduce error pruning trees (REPTree), and classification and regression trees (CART) were employed in order to obtain models that could predict sex in unidentified skeletal remains. Under cross-validation, the proposed models correctly estimated sex in 90.2-92.0% of cases (bias ranging from 1.8% to 4.5%). The models were evaluated in an independent test sample (30 females; 30 males) from the 21st Century Identified Skeletal Collection (University of Coimbra, Portugal), with a sex allocation accuracy ranging from 90.0% to 91.7% (bias from 3.3% to 10.0%). Overall, data mining classifiers, especially the REPTree, performed better than the traditional classifiers (LR and LDA), maximizing overall accuracy and minimizing bias. This study emphasizes the significant value of bone densitometry to estimate sex in cadaveric remains in diverse states of preservation and completeness, even human remains with soft tissues.
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Affiliation(s)
- Francisco Curate
- Research Centre for Anthropology and Health, Department of Life Sciences, University of Coimbra, Coimbra, Portugal; Laboratory of Forensic Anthropology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal; Interdisciplinary Center for Archaeology and Evolution of Human Behavior, University of Algarve, Faro, Portugal.
| | | | - Izilda Ferreira
- The Coimbra Hospital and University Centre, Coimbra, Portugal
| | - Eugénia Cunha
- Laboratory of Forensic Anthropology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal; Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
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Curate F, Coelho J, Gonçalves D, Coelho C, Ferreira MT, Navega D, Cunha E. A method for sex estimation using the proximal femur. Forensic Sci Int 2016; 266:579.e1-579.e7. [PMID: 27373600 DOI: 10.1016/j.forsciint.2016.06.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 04/26/2016] [Accepted: 06/07/2016] [Indexed: 11/27/2022]
Abstract
The assessment of sex is crucial to the establishment of a biological profile of an unidentified skeletal individual. The best methods currently available for the sexual diagnosis of human skeletal remains generally rely on the presence of well-preserved pelvic bones, which is not always the case. Postcranial elements, including the femur, have been used to accurately estimate sex in skeletal remains from forensic and bioarcheological settings. In this study, we present an approach to estimate sex using two measurements (femoral neck width [FNW] and femoral neck axis length [FNAL]) of the proximal femur. FNW and FNAL were obtained in a training sample (114 females and 138 males) from the Luís Lopes Collection (National History Museum of Lisbon). Logistic regression and the C4.5 algorithm were used to develop models to predict sex in unknown individuals. Proposed cross-validated models correctly predicted sex in 82.5-85.7% of the cases. The models were also evaluated in a test sample (96 females and 96 males) from the Coimbra Identified Skeletal Collection (University of Coimbra), resulting in a sex allocation accuracy of 80.1-86.2%. This study supports the relative value of the proximal femur to estimate sex in skeletal remains, especially when other exceedingly dimorphic skeletal elements are not accessible for analysis.
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Affiliation(s)
- Francisco Curate
- Research Centre for Anthropology and Health, Department of Life Sciences, University of Coimbra, Coimbra, Portugal; Interdisciplinary Center for Archaeology and Evolution of Human Behavior, University of Algarve, Faro, Portugal; Laboratory of Forensic Anthropology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal.
| | - João Coelho
- Laboratory of Forensic Anthropology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal; Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - David Gonçalves
- Research Centre for Anthropology and Health, Department of Life Sciences, University of Coimbra, Coimbra, Portugal; Laboratory of Forensic Anthropology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal; Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal; Archaeosciences Laboratory, Directorate General for Cultural Heritage and LARC/CIBIO/InBIO, Lisboa, Portugal
| | - Catarina Coelho
- Laboratory of Forensic Anthropology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal; Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Maria Teresa Ferreira
- Research Centre for Anthropology and Health, Department of Life Sciences, University of Coimbra, Coimbra, Portugal; Laboratory of Forensic Anthropology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal; Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - David Navega
- Laboratory of Forensic Anthropology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal; Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Eugénia Cunha
- Laboratory of Forensic Anthropology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal; Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
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Li S, Chang SM, Jin YM, Zhang YQ, Niu WX, Du SC, Zhang LZ, Ma H. A mathematical simulation of the tip-apex distance and the calcar-referenced tip-apex distance for intertrochanteric fractures reduced with lag screws. Injury 2016; 47:1302-8. [PMID: 27087281 DOI: 10.1016/j.injury.2016.03.029] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 03/24/2016] [Accepted: 03/24/2016] [Indexed: 02/02/2023]
Abstract
BACKGROUND As a predictor of the risk of lag screw cutout, it was recommended that keeping tip-apex distance (TAD)<25mm and placing the screw centrally or inferiorly, but positioning the lag screw too inferiorly in the head would produce TAD>25mm. We aim to simulate various positions of the lag screw in the femoral head and identify whether 25mm is a suitable cut-off value that favours all sizes of femoral heads with intertrochanteric fractures of the hip. METHODS Using a general mathematical software, the positions of the screw tip points were simulated. The virtual anterior-posterior and lateral views were then visualised, and the locus of the screw tips was projected into a Cartesian coordinate system according to the TAD and calcar-referenced tip-apex distance (CalTAD) formulas. Each original virtual anterior-posterior and lateral image was zoomed and compiled to match a calculated average image. The screw tip points were recorded, traced and compiled into volumes which could be used to visualise the screw's movements and positioning within the femoral head. The extracted volumes were calculated when 10mm<TAD<25mm and 10mm<CalTAD<25mm, and the region where these two volumes overlapped was also calculated. Suitable positions for the screw tip were then assessed. RESULTS For the TAD calculation, the shape of the traced screw tip points had a pancake-like appearance, while the CalTAD plot produced a teardrop-shaped region. The volume ratios of TAD, CalTAD and overlapping region relative to the femoral head volume were respectively 3.51±1.30%, 5.19±1.62% and 2.64±1.32%. The volumes of the traced TAD, CalTAD and overlapping regions increased slower than the volume of an idealised sphere. CONCLUSION Positioning the lag screw should address geometrical effects of both tip-apex distance and femoral head size, with an emphasis on measuring the position of the screw tip for the suitable zone by volume ratio. The previous 25mm TAD cut-off value should be adjusted according to the individual femoral head size.
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Affiliation(s)
- Shuang Li
- Department of Orthopaedic Surgery, Yangpu Hospital, Tongji University School of Medicine, Shanghai, China
| | - Shi-Min Chang
- Department of Orthopaedic Surgery, Yangpu Hospital, Tongji University School of Medicine, Shanghai, China.
| | - Yan-Min Jin
- College of Surveying and Geo-Informatics, Tongji University, China
| | - Ying-Qi Zhang
- Department of Orthopaedic Surgery, Yangpu Hospital, Tongji University School of Medicine, Shanghai, China
| | - Wen-Xin Niu
- Yang Zhi Rehabilitation Hospital, Tongji University School of Medicine, Shanghai, China
| | - Shou-Chao Du
- Department of Orthopaedic Surgery, Yangpu Hospital, Tongji University School of Medicine, Shanghai, China
| | - Li-Zhi Zhang
- Department of Orthopaedic Surgery, Yangpu Hospital, Tongji University School of Medicine, Shanghai, China
| | - Hui Ma
- Department of Orthopaedic Surgery, the First Rehabilitation Hospital of Shanghai, China
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Impact of secular trends on sex assessment evaluated through femoral dimensions of the Czech population. Forensic Sci Int 2016; 262:284.e1-6. [DOI: 10.1016/j.forsciint.2016.02.042] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 02/20/2016] [Accepted: 02/22/2016] [Indexed: 11/20/2022]
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