Diaphyseal Length Research Articles

The impact of urbanization on growth patterns of non‐adults in medieval England

AbstractIncreasing urbanization seen during the medieval period (7th to 16th centuries) is associated with adverse living conditions that may have negatively impacted childhood growth via the influence of infectious diseases and nutritional deficiencies due to increasing population density and periodic food shortages. This study aims to compare the growth of non‐adults (less than 12 years of age) from urban, proto‐urban, and rural environments from medieval England to determine whether settlement type influenced child health, and by proxy overall population health, during this period. Tibial and femoral maximum diaphyseal lengths and dental age of non‐adults (0–12 years) from urban St. Gregory's Priory (n = 60), urban York Barbican (n = 16), proto‐urban Black Gate (n = 38), and rural Raunds (n = 30) were examined using z‐scores. The results reveal that non‐adults < 2 years from St. Gregory's Priory had the lowest growth values followed by Raunds, Black Gate, and York Barbican with the highest growth values. Further, non‐adults 2–12 years from York Barbican had the lowest growth values followed by Raunds, Black Gate, and St. Gregory's Priory with the higher growth values. The femoral and tibial diaphyseal growth values are explored within the context of breastfeeding and weaning practices, stability of economies, and environmental conditions.

Determining the normal range of the calcaneus-metatarsal angles in the second-trimester fetal ultrasound examination using the novel measurement technique "Melek's angles": A cross-sectional study.

The aim of this study is to establish the normal calcaneus-metatarsal angles in order to facilitate the recognition of fetal foot deformities. Therefore, a novel measurement technique was determined using ultrasound and applied to nonanomalous fetuses in the 18th to 23rd gestational weeks. This cross-sectional study included 100 low-risk, nonanomalous fetuses in the 18th to 23rd weeks of gestation. Measurements were obtained using the novel measurement technique in fetal ultrasound examination. Fetal biometry, foot sole length, first and fifth metatarsal diaphyseal length measurements were taken. The acute angle measurement of the line segment passing between the calcaneus outer lateral and proximal fifth metatarsal with the long axis of the first metatarsal diaphysis (CA-mtt1) and long axis of the fifth metatarsal diaphysis (CA-mtt5) was taken. Interobserver and intraobserver reliabilities were assessed by intraclass correlations (ICC). A strong positive correlation was detected between bi-parietal diameter (BPD) and foot sole length, first metatarsal diaphyseal length and fifth metatarsal diaphyseal length (p < 0.0001). No significant correlation of these CA-mtt1 and CA-mtt5 angles with BPD was detected (p = 0.35, p = 0.82, respectively). The data suggest that the CA-mtt1 and CA-mtt5 angles remained consistently within a narrow range and were determined to be 20.0° ± 8.7° and 7.8° ± 7.5°, respectively. Intraobserver and interobserver agreement for CA-mtt1 angle was moderate (ICC, 0.655) and moderate (ICC, 0.615), for CA-mtt5 angle was moderate (ICC, 0.631) and moderate (ICC, 0.605), respectively. A normal reference range was established for fetal sole length, first metatarsal diaphysis length, fifth metatarsal diaphysis length, CA-mtt1 angle, and CA-mtt5 angle in the 18th to 23rd weeks of gestation. It was determined that the CA-mtt1 and CA-mtt5 angles remained relatively constant within a narrow range throughout the assessed gestational weeks.

AGE ESTIMATION USING DIAPHYSEAL LONG BONE LENGTHS IN A NON-ADULT SKELETAL SAMPLE FROM GONUR DEPE, TURKMENISTAN

Introduction. The aim of this study is to provide group-specific regression equations for age estimation of immature human skeletal remains younger than 12 years of age from the diaphyseal length of the six long bones. Further, to compare inverse and classical calibration models for age estimation and the suitability of previously published regression methods for archaeological and present-day populations in relation to the analyzed sample. Materials and methods. The studied sample consists of 128 non-adult individuals from Gonur Depe – the major BMAC site in Turkmenistan (2300–1500 BCE). Regression formulae were obtained for each of the six long bones, separately for entire sample (0–12 years of age) and for two subsamples below and above 2 years of age. For each equation the coefficient of determination (R2) and F-statistics were calculated. Residuals were tested for normality of distribution, autocorrelation, homoscedasticity, and the equality of mean to zero (one-sample t-test). Comparison between inverse and classical calibration was provided using paired samples t-test. To assess the applicability of other regression formulae to the studied sample both the mean residuals (MR) and mean of the absolute value of the residuals (MAR) were calculated, as an estimate of bias and accuracy respectively. Results. All regression models showed a strong statistical significance and high R2 value. The slope coefficients of the regression lines of diaphyseal length upon age are greater for the upper limb bones both in the entire sample and two subsamples separately. The lower limb bones are characterized by lower growth rates. In contrast to the inverse calibration, for the classical model the mean standard errors (MSE) were smaller for the upper limb bones rather than for the lower limb bones. For the lower limb bones the standard error of the estimate (SE) was generally smaller in inverse formulae. Comparison of both models for the femur however shows their equal performance. For the exception of proposed and classical calibration formulae all inverse models for femur diaphyseal length show consistent differences from zero in relation to the studied sample. Discussion. The inverse and classical calibration models as a technique for age estimation using diaphyseal long bone lengths are both equally applicable in the studied sample. It is recommended to use the equations for the lower limb bones in the inverse model and for the upper limb bones in the classical model. The Gonur Depe population is characterized by relatively higher growth rates of the upper limb bones and distal limb segments relative to the proximal ones. Most of the previously published inverse calibration models are not recommended for uncritically use due to the high risk of obtaining biased estimates on samples that are different chronologically and/or territorially.

New More Generic and Inclusive Regression Formulae for the Estimation of Stature from Long Bone Lengths in Children

Existing child stature estimation methods have a number of disadvantages. This paper addresses some of these limitations by developing regression-based stature estimation formulae that are more generic and inclusive. A sample of 142 individuals under 12 years of age from the Hamann—Todd Human Osteological Collection and the New Mexico Decedent Images Database were used to generate five least squares linear regression formulae to estimate stature from the diaphyseal length of long bones. All models showed excellent fits to the data (R2 close to or at 0.98), and internal validation confirmed the stability and accuracy of model parameters. External validation was performed using a sample of 14 individuals from the Lisbon Collection and the Victoria Institute of Forensic Medicine. Overall, the humerus provides the most accurate estimate of stature, but the femur and tibia showed the greatest coverage. These formulae can be used in a variety of contexts and are not dependent on group affiliation, including sex.

Estimation of Gestational Age from Human Fetal Diaphyseal Length of Femur

Introduction: Length of femur is the good marker of late gestational age. Femur length denotes exact gestational age and helps in classification of fetus as pre-term, term or post-term. Also, it is an important parameter in medicolegal cases like decomposed fetuses, infanticide and mutilated parts of fetus. This study was mainly conducted to estimate the gestational age from human fetal diaphyseal length of femur. Material and Methods: Study was conducted on 35 human aborted fetuses obtained from OBGY department of MGM Medical college, Aurangabad and 70 femurs of right and left side were dissected out in Anatomy department of same institute for the fetal femur morphometry and its correlation with gestational age. Fetuses were divided into 4 groups as A, B, C, D according to their gestational age and diaphyseal length i.e., measurement from greater trochanter to lateral condyle (L1) was measured. Results: In each group following parameter was analyzed by descriptive statistics. The Mean +SD, minimum and maximum values for diaphyseal length of femur (L1) was calculated in each group. L1 of right femur increases gradually from 38.96 mm in group A to 74.294 mm in 32 in group D. Similarly for left femur, the diaphyseal length increase gradually from 38.971 mm in group A to 76.594 mm in group D. The mean diaphyseal length L1 of both right and left side is 38.95 in group A and 75.44 in group D, shows linear correlation with gestational age. It was found that femur length gives a positive correlation with gestational age. Conclusion: Diaphyseal length of fetal femur, is one of the most important parameter for the estimation of gestational age in 2nd and 3rd trimester.

Особенности продольного роста у скотоводческого населения Южного Урала и земледельцев Средней Азии эпохи бронзы: анализ стандартизированных оценок

Introduction. In this paper, we compared patterns of longitudinal long bone growths of the Late Bronze Age population from Southern Urals, representing pastoral communities, predominantly cattle breeders, and the relatively synchronous agricultural population from Central Asia using standardized z-scores. Materials and methods. The analyzed sample comes from two cemeteries of the Srubnaya culture in Pre-Urals (Karanayevsky and Chumarovo-1), and two cemeteries of the Srubnaya-Alakul cultural type in Trans-Urals (Nepluyevsky and Yulaly-8). The comparative sample represents data from Gonur Depe, a Bronze Age proto-urban center in Southeastern Turkmenistan. The sample sizes were 32 and 56 individuals respectively, aged between 2 and 12 years old. The measurements of all six long bones and updated reference Maresh standards (mid-20th century, USA) were used to calculate z-scores. The obtained z-scores were analyzed using both parametric methods and nonparametric statistics. Results. Z-scores for the diaphyseal lengths differed significantly between the two analyzed samples. The distribution of z-scores for the Gonur Depe sample was more noticeably shifted towards lower values. In the Southern Ural sample, 6.7% of children had z-scores no lower than those in the reference group, while in the Gonur Depe sample this value constituted only 0.6%. Z-scores for the upper limb bones in both groups were significantly higher than those for the lower limb bones. In the Southern Ural sample, children under 6 years of age had significantly higher z-scores compared to 9–12-year old children. No such differences were found in the Gonur Depe sample. Discussion. The pooled Bronze Age sample from Southern Urals showed overall less stunting from the reference group compared to the Gonur Depe sample. This is consistent with the hypothesis of a smaller long bone lengths and shorter stature in agricultural compared to pastoral populations. In both groups, the lower limb bones had lower z-scores compared to the upper limb bones, indicating that growth stunting relative to the reference values is more expressed for the lower limbs.@ 2023. This work is licensed under a CC BY 4.0 license

Fetal Humeral Diaphyseal Length in the Second Trimester - A Radiographic Observational Study among Indian Population.

The present study was performed to provide a normal reference range for humerus diaphysis length at the second trimester of pregnancy in an Indian population. This cross-sectional study was performed on 25 radiographs of aborted normal human fetuses of gestational age (GA) between 13th and 28th weeks. The radiographs were used to measure the maximum length of the humerus using a vernier calliper. Data were collected, tabulated, and statistically analyzed. The mean diaphyseal length of humerus at the fourth lunar month was 22.18 ± 6.59 mm, and at the seventh lunar month, it was 41.39 ± 10.08 mm. Simple linear regression analysis shows a strongly significant linear relationship of humerus length with GA, biparietal diameter, head circumference, and abdomen circumference. We have provided a normal reference range for humerus diaphysis length at the second trimester of pregnancy in an Indian population.

Femur development in fetal growth restriction as observed on prenatal magnetic resonance imaging.

To investigate human femur development in fetal growth restriction (FGR) by analyzing femur morphometrics and distal epimetaphyseal features on prenatal magnetic resonance imaging (MRI). This was a retrospective study of 111 fetuses (mean gestational age (GA), 27 + 2 weeks (range, 19-35 weeks)) with FGR associated with placental insufficiency without other major abnormalities and 111 GA-matched normal controls. On 1.5-Tesla echoplanar MRI, femur morphometrics, including diaphyseal length, epiphyseal length and epiphyseal width, were assessed. Using a previously reported grading system, epimetaphyseal features, including cartilaginous epiphyseal shape, metaphyseal shape and epiphyseal ossification, were analyzed qualitatively. To compare FGR cases and controls, the paired t-test was used to assess morphometrics, generalized estimating equations were used for epimetaphyseal features and time-to-event analysis was used to assess the visibility of epiphyseal ossification. There were significant differences in femur morphometrics between FGR cases and controls (all parameters, P < 0.001), with bone shortening observed in FGR. No significant differences were found in the distribution of epimetaphyseal features between FGR cases and controls (epiphyseal shape, P = 0.341; metaphyseal shape, P = 0.782; epiphyseal ossification, P = 0.85). Epiphyseal ossification was visible at a median of 33.6 weeks in FGR cases and at 32.1 weeks in controls (P = 0.008). On prenatal MRI, cases with FGR associated with placental insufficiency exhibit diaphyseal and epiphyseal shortening of the femur. However, FGR cases and normal controls share similarly graded distal epimetaphyseal features. Consequently, these features may not be appropriate MRI characteristics for the identification of FGR. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Variation in ontogenetic trajectories of limb dimensions in humans is attributable to both climatic effects and neutral evolution

Previous studies showed that there is variation in ontogenetic trajectories of human limb dimensions and proportions. However, little is known about the evolutionary significance of this variation. This study used a global sample of modern human immature long bone measurements and a multivariate linear mixed-effects model to study 1) whether the variation in ontogenetic trajectories of limb dimensions is consistent with ecogeographic predictions and 2) the effects of different evolutionary forces on the variation in ontogenetic trajectories. We found that genetic relatedness arising from neutral (nonselective) evolution, allometric variation associated with the change in size, and directional effects from climate all contributed to the variation in ontogenetic trajectories of all major long bone dimensions in modern humans. After accounting for the effects of neutral evolution and holding other effects considered in the current study constant, extreme temperatures have weak, positive associations with diaphyseal length and breadth measurements, while mean temperature shows negative associations with diaphyseal dimensions. The association with extreme temperatures fits the expectations of ecogeographic rules, while the association with mean temperature may explain the observed among-group variation in intralimb indices. The association with climate is present throughout ontogeny, suggesting an explanation of adaptation by natural selection as the most likely cause. On the other hand, genetic relatedness among groups, as structured by neutral evolutionary factors, is an important consideration when interpreting skeletal morphology, even for nonadult individuals.

Proximal Focal Femoral Deficiency: Prenatal Diagnosis of a Rare Congenital Skeletal Anomaly

A rare case of proximal focal femoral deficiency (PFFD) is presented due to concerns for a short fetal femur. A 32-year-old patient (G3P2002) was reviewed at 37 weeks of gestation. Sonography revealed an appropriately maturing female fetus, with a left femoral diaphyseal length of 36.1 mm (&lt;1st percentile), while the right measured 71.4 mm (35th percentile). The proximal epiphysis, head, and trochanter of the left fetal femur were absent on 3D sonography, with significant overlap of the femur on the pubic bone. At delivery, the baby weighed 3240 g, with a lower limb-length discrepancy of 56 mm. A radiograph confirmed left-sided hypoplastic proximal femur, absent femoral head, and a poorly formed acetabulum. The baby was conservatively managed, with plans for possible surgery and limb prosthesis. A high index of suspicion and capacity building to facilitate prenatal diagnosis are essential for optimal care of babies with PFFD.

Combining Continuous and Categorical Data Modeling in Developmental Age Estimation Using Hierarchical Bayes

Residual correlations (correlations that persist after accounting for the effect of chronological age) between variables can have a significant impact on final age estimates. Such correlations can result in overly narrow age intervals and high error rates when not accounted for. Modeling correlations can be mathematically problematic across mixed data types. Hierarchical modeling can incorporate continuous and categorical traits into a single model that accounts for correlated variables while reducing computationally expensive calculations. This paper demonstrates a Bayesian hierarchical modeling approach in which trait variables were grouped by data type or bodily system and used to produce separate age estimates with any appropriate model. These age estimates were combined into a single estimate using a multivariate normal model via nested cross-validation. The data used included nine diaphyseal length measurements and 29 epiphyseal fusion and ossification sites from 179 individuals in the publicly available U.S. Subadult Virtual Anthropology Database. Diaphyseal ages were modeled with linear regression and epiphyseal ages with random forest regression. Age estimates from the hierarchical model had reduced bias relative to diaphyseal or epiphyseal maximum likelihood estimates alone. Combined-indicator age intervals from 95% highest density regions (HDRs) were on average 15% narrower than those from diaphyseal 95% HDRs while success rates were 2% lower (91% vs. 93%). Functional example code is provided. A general hierarchical modeling approach may be applicable to other areas of skeletal analysis that employ correlated variables of mixed data types including adult age estimation and ancestry estimation.

Comparison of the strength parameters of the bilateral third metacarpal bones in horses by pQCT

The third metacarpal (MC3) bone, along with the proximal phalanx, is one of the bones that are most prone to injury in sport horses. To date, no detailed analysis has been conducted that would compare the strength parameters of bilateral MC3 bones taking into account differences depending on the site of measurement. The aim of the study was to compare strength parameters between the left and right MC3 bones in horses at 10%, 20%, 30%, 40%, 50%, 60%, 70% and 80% of the bone length using peripheral quantitative computed tomography (pQCT). The research material comprised isolated bilateral MC3 bones from 21 horses (age range: 3-27 years). The structure of these bones was measured using high-resolution pQCT. The following bone parameters were determined: polar strength strain index, strength strain index X and strength strain index Y. The computed tomographic analysis of the MC3 bones was carried out at sections from 10% to 80% (every 10%) of the bone length. The statistical analysis showed that in most cases the strength parameters calculated using pQCT were significantly higher for the right MC3 bones at 10%, 20% and 50% of the bone length, i.e. at the proximal metaphysis and at the proximal diaphysis. However, strength parameters measured at 60% and 80% of the diaphyseal length, i.e. at the distal diaphysis, were significantly higher for the left MC3 bones. Further studies of the MC3 bones parameters should focus on the vicinity of the proximal metaphysis and at the proximal diaphysis.

Age-at-death standards for Mesoamerican Prehispanic and colonial infant, child, and juvenile skeletons.

This study aims to develop age-at-death standards for Valley of Mexico skeletal collections. Using 159 individuals, with a dental age-at-death between 0 to 15 years, we develop linear and quadratic inverse regression models of age-at-death estimation between dental age and the diaphyseal length of the six long bones. A blind test for both regressions was performed, also a regression developed for a Maya group was carried out. We also compared skeletal growth of our sample by applying regressions developed for Maya and North American populations to assess the magnitude of the differences among ethnically unrelated populations. Our regressions yielded a close correlation between the diaphyseal length and dental age, especially femur and radius. It is noticeable that the disparities between younger and older age categories, the latter presenting larger standard deviations. Quadratic regression fitted better than linear and Maya regressions, and the differences of age-at-death distributions are significant. The skeletal growth curve of the Valley of Mexico is statistically different from other Native American groups. We conclude that for the present standards, despite the high degree of variance, the quadratic regression is a better applicable age estimator, when it is applied to biologically close populations.

Bioarchaeological insights into disability: Skeletal dysplasia from the Iron Age northern China

AbstractSkeletal dysplasia is mainly caused by genetic mutations or endocrine abnormality. In this study, a case of disproportionate dwarfism from the Iron Age Beishenjiaqiao cemetery in Xi'an, China is analyzed from the perspective of bioarchaeology. The individual shows disproportionately short stature, with reduced long‐bone diaphyseal length especially of both humeri, unfused proximal humerus epiphyses, abnormal development of the shoulder and hip joints, left femoral head necrosis, and unusually gracile left femur and tibia shaft, demonstrating limited mobility and labor capacity. Hypothyroidism, pseudoachondroplasia, and multiple epiphyseal dysplasia are the most likely possible diagnoses although there are other possibilities. By combining the archaeological evidences and historical records, it is speculated that this individual lived a normal life and was well treated during her lifetime. Overall, this rare case concerning dwarfism not only enriches our knowledge of skeletal dysplasia among ancient Chinese in northern China but also demonstrates the humanitarian attitude of ancient society toward the disability.

The relationship between bipedalism and growth: A metric assessment in a documented modern skeletal collection (Certosa Collection, Bologna, Italy).

ObjectivesLong bone variations during growth are susceptible to the combined action of nutritional, hormonal, and genetic factors that may modulate the mechanical forces acting upon growing individuals as they progressively acquire a mature gait. In this work, we explore diaphyseal length and breadth variations of tibia and fibula during ontogeny (a) to test the presence of changes in relation to early toddling, and (b) to further our understanding of developmental patterns in relation to sex.Materials and MethodsLengths, breadths, and indices were analyzed on right and left leg bones of 68 subadult individuals (Human Identified Skeletal Collection of the University of Bologna, Italy). Analyses included intersex and age classes (1, 0–1 year; 2, 1.1–3 years; 3, 3.1–6 years) comparisons, linear regressions with age and assessment of correlation among tibial and fibular measurements, as well as principal component analysis.ResultsA significant difference emerged among age class 1 and the others. Age class 1 and 3 differ between them, while age class 2 overlaps with the others. No sex dimorphism was detected. All measurements were strongly correlated with age. Tibial and fibular measurements correlated with each other.ConclusionsOur results relate the progressive emergence of toddling attempts in growing individuals at the end of the first year of age. No significant sex differences were found, suggesting that tibial and fibula growth might diverge between sexes in later childhood. We provide quantitative data regarding tibial and fibular linear growth and its timing in a modern documented osteological sample from Italy.

Interpreting error in the estimation of skeletal growth profiles from past populations: An example demonstrating skeletal growth in historic African American communities.

The study of growth in the past is a critical component of bioarcheological analyses. However, our understanding of growth in the past is subject to a number of methodological challenges. This study aims to model the skeletal growth of past populations by considering the challenges associated with the data collection process and the challenges associated with the age estimation procedures. We use skeletal remains from two historic African American cemeteries in the American South to model femoral diaphyseal length-for-age. We estimate the age of each individual using dental development techniques and present growth curves as both a product of the maximum likelihood (MLE) age estimate and the estimated posterior age distribution. Growth was compared against a reference sample from the University of Colorado Child Research Council Study. The results of our analyses showed that femoral diaphyseal length in two historic African American communities is small-for-estimated age as compared to a modern reference sample. However, the magnitude and characterization of this difference is variable when taking into account the broader posterior age distribution. Both samples may be small-for-age due to physiological stress associated with racism, inequality, and the compounding effects of early urbanization. However, the interpretation of growth in the past is muddled when considering the relationship between the study sample and the reference sample, when accounting for uncertainty in the age estimation procedure, and the error-inducing steps taken during the data collection process. Future interpretation of skeletal growth in the past must include a full account of the possible sources of error in order to present an accurate representation of growth.

Age estimation of immature human skeletal remains from mandibular and cranial bone dimensions in the postnatal period

Age estimation is one of the crucial first steps in the identification of human skeletal remains in both forensic and archeological contexts. In the postnatal period, age is traditionally estimated from dental development or skeletal growth, typically long bone diaphyseal length. However, in many occasions other methods are required. This study provides alternative means of estimating age of juvenile remains from the size of several cranial bones and the mandible. A sample of 185 identified juvenile skeletons between birth and 13 years of age from two European collections were used (Lisbon and Spitalfields). Measurements of the frontal, occipital-lateralis, occipital-basilaris, occipital-squamous, zygomatic, maxilla, and mandible were used to calculate classical calibration regression formulae for the sexes combined. The sample was divided into three age groups birth-2 years, 2–6 years, and 2–12.9 years, depending on bone and its growth trajectory. For all the bones, measurements of the youngest age groups yielded the most precise age estimates. The vault bones on average yielded the best performing models, with the frontal bone having the most precise of all. The mandible performed on par with the best performing cranial bones, particularly in individuals under the age of 2 years. This study provides one of the most comprehensive approaches to juvenile age estimation based on bones of the skull, providing a resource that potentially can help estimate age of juvenile skeletons from a variety of circumstances.

Interpolation of the Maresh diaphyseal length data for use in quantitative analyses of growth

AbstractThe Maresh data are commonly used in bioarcheological growth studies as a representation of diaphyseal growth in a modern and healthy group of children. However, several problems with the way the data were reported have limited its use in quantitative analyses of growth. In this paper, we present updated and interpolated values for long bone length for age for use in calculating z‐scores, percentages of expected length, and other quantitative measures of growth. The Maresh mean and mean + 1 standard deviation values for the sexes separately and combined were first corrected for radiographic magnification. Several modeling approaches were then evaluated. This testing suggested that the best fit was provided by two third‐order polynomials fit to data ≤24 and ≥24 months, respectively. The resulting regressions were used to calculate age‐specific mean and standard deviation values in 1‐month intervals from birth until 12 years (0–144 months). Differences between the original and new values are minimal and do not exceed 1 mm. However, as the old Maresh values required rounding age down to the last attained threshold by as much as 5 months, there are differences between z‐scores calculated with original versus new values of up to 2 z‐score units, especially in children under 3 years of age where growth velocity is highest. Although these updated values do not solve the problems that made age estimation from the Maresh data unadvisable, they will be of use to researchers in conducting more precise growth studies in bioarcheological contexts.

Length unstable femoral fractures: A misnomer?

BACKGROUNDFlexible intramedullary nailing (FIMN) is relatively contraindicated for pediatric length unstable femoral fractures.AIMTo evaluate FIMN treatment outcomes for pediatric diaphyseal length unstable femoral fractures in patients aged 5 to 13 years.METHODSThis retrospective study includes pediatric patients (age range 5-13 years) who received operative treatment for a diaphyseal femoral fracture at a single institution between 2013 and 2019. Length unstable femur fractures treated with FIMN were compared to treatment with other fixation methods [locked intramedullary nailing (IMN), submuscular plating (SMP), and external fixation] and to length stable fractures treated with FIMN. Exclusion criteria included patients who had an underlying predisposition for fractures (e.g., pathologic fractures or osteogenesis imperfecta), polytrauma necessitating intensive care unit care and/or extensive management of other injuries, incomplete records, or no follow-up visits. Patients who had a length stable femoral fracture treated with modalities other than FIMN were excluded as well.RESULTSNinety-five fractures from ninety-two patients were included in the study and consists of three groups. These three groups are length unstable fractures treated with FIMN (n = 21), length stable fractures treated with FIMN (n = 45), and length unstable fractures treated with either locked IMN, SMP, or external fixator (n = 29). P values < 0.05 were considered statistically significant. Patient characteristic differences that were statistically significant between the groups, length unstable with FIMN and length unstable with locked IMN, SMP, or external fixator, were average age (7.4 years vs 9.3 years, respectively), estimated blood loss (29.2 mL vs 98 mL, respectively) and body mass (27.8 kg vs 35.1 kg, respectively). All other patient characteristic differences were statistically insignificant. Regarding complications, length unstable with FIMN had 9 total complications while length unstable with locked IMN, SMP, or external fixator had 10. Grouping these complications into minor or major, length unstable with locked IMN, SMP, or external fixator had 6 major complication while length unstable with FIMN had 0 major complications. This difference in major complications was statistically significant. Lastly, when comparing patient characteristics between the groups, length unstable with FIMN and length stable with FIMN, all characteristics were statistically similar except time to weight bearing (39 d vs 29 d respectively). When analyzing complication differences between these two groups (9 total complications, 0 major vs 20 total complications, 4 major), the complication rates were considered statistically similar.CONCLUSIONFIMN is effective for length unstable fractures, having a low rate of complications. FIMN is a suitable option for length stable and length unstable femur fractures alike.

Genetic mapping of distal femoral, stifle, and tibial radiographic morphology in dogs with cranial cruciate ligament disease.

Cranial cruciate ligament disease (CCLD) is a complex trait. Ten measurements were made on orthogonal distal pelvic limb radiographs of 161 pure and mixed breed dogs with, and 55 without, cranial cruciate partial or complete ligament rupture. Dogs with CCLD had significantly smaller infrapatellar fat pad width, higher average tibial plateau angle, and were heavier than control dogs. The first PC weightings captured the overall size of the dog’s stifle and PC2 weightings reflected an increasing tibial plateau angle coupled with a smaller fat pad width. Of these dogs, 175 were genotyped, and 144,509 polymorphisms were used in a genome-wide association study with both a mixed linear and a multi-locus model. For both models, significant (pgenome <3.46×10−7 for the mixed and< 6.9x10-8 for the multilocus model) associations were found for PC1, tibial diaphyseal length and width, fat pad base length, and femoral and tibial condyle width at LCORL, a known body size-regulating locus. Other body size loci with significant associations were growth hormone 1 (GH1), which was associated with the length of the fat pad base and the width of the tibial diaphysis, and a region on CFAX near IRS4 and ACSL4 in the multilocus model. The tibial plateau angle was associated significantly with a locus on CFA10 in the linear mixed model with nearest candidate genes BET1 and MYH9 and on CFA08 near candidate genes WDHD1 and GCH1. MYH9 has a major role in osteoclastogenesis. Our study indicated that tibial plateau slope is associated with CCLD and a compressed infrapatellar fat pad, a surrogate for stifle osteoarthritis. Because of the association between tibial plateau slope and CCLD, and pending independent validation, these candidate genes for tibial plateau slope may be tested in breeds susceptible to CCLD before they develop disease or are bred.