Quantitative morphological analysis framework of infant cranial sutures and fontanelles based on CT images.

Characterizing the suture morphological variation is a crucial step to investigate the influence of sutures on infant head biomechanics. This study aimed to establish a comprehensive quantitative framework for accurately capturing the cranial suture and fontanelle morphologies in infants. A total of 69 CT scans of 2-4 month-old infant heads were segmented to identify semilandmarks at the borders of cranial sutures and fontanelles. Morphological characteristics, including length, width, sinuosity index (SI), and surface area, were measured. For this, an automatic method was developed to determine the junction points between sutures and fontanelles, and thin-plate-spline (TPS) was utilized for area calculation. Different dimensionality reduction methods were compared, including nonlinear and linear principal component analysis (PCA), as well as deep-learning-based variational autoencoder (VAE). Finally, the significance of various covariates was analyzed, and regression analysis was performed to establish a statistical model relating morphological parameters with global parameters. This study successfully developed a quantitative morphological framework and demonstrate its application in quantifying morphologies of infant sutures and fontanelles, which were shown to significantly relate to global parameters of cranial size, suture SI, and surface area for infants aged 2-4 months. The developed framework proved to be reliable and applicable in extracting infant suture morphology features from CT scans. The demonstrated application highlighted its potential to provide valuable insights into the morphologies of infant cranial sutures and fontanelles, aiding in the diagnosis of suture-related skull fractures. Infant suture, Infant fontanelle, Morphological variation, Morphology analysis framework, Statistical model.

The role of alternative hypotheses in reducing bias in forensic medical experts' decision making.

Medical opinions are often essential evidence in criminal cases but relatively little is known about the factors that impact forensic doctors' decision making. This research examines the role and impact of having an alternative hypothesis while forming a medical opinion. A scenario-based experiment with forensic doctors (n = 20) was conducted. In two out of three scenarios, the existence of alternative hypotheses impacted the actual opinions reached, the confidence in the judgments and the perceived consistency with the plaintiff hypothesis. Investigative and legal actors should be aware of the possibility of biases and importance of having alternative hypotheses when requesting and evaluating medical opinions.

Retinal haemorrhage in infants investigated for suspected maltreatment is strongly correlated with intracranial pathology.

AIM: To test the two prevailing hypotheses regarding the aetiology of infant retinal haemorrhage: (a) traction forces exerted by the lens and/or corpus vitreum on the retina during infant shaking or (b) retinal vessel leakage secondary to intracranial pathology and raised intracranial pressure. METHODS: Comparison of medical findings and reported type of trauma in infants investigated for suspected physical abuse with presence (n = 29) or non-presence of retinal haemorrhage (RH) (n = 119). RESULTS: Intracranial pathology was recorded in 15 (13%) of the non-RH cases and in 27 (97%) of the RH cases (p < 0.0001). All 18 infants with bilateral RH had intracranial pathology. Of 27 infants subjected to witnessed or admitted shaking, two were in the group with RH. One had a single unilateral RH and no intracranial pathology. The other had bilateral RH and intracranial pathology with non-specific white matter changes, acute subdural and subarachnoid haemorrhages, and suspected cortical venous thrombosis. In 15 RH cases, there was no trauma reported and no findings other than RH and intracranial pathology. Accidental blunt head trauma was reported in 7 RH cases. CONCLUSION: The present study indicates that RH in infants is secondary to intracranial pathology of non-specific aetiology.

External Hydrocephalus as a Cause of Infant Subdural Hematoma: Epidemiological and Radiological Investigations of Infants Suspected of Being Abused.

BACKGROUND: Acute subdural hematoma (ASDH) and chronic subdural hematoma (CSDH) in infants have been regarded as highly specific for abuse. Other causes of CSDH have not been investigated in a large population. PURPOSE: The purpose of this study was to investigate to what extent external hydrocephalus is present in infants with ASDH and CSDH undergoing evaluation for abuse. MATERIAL AND METHODS: Eighty-five infants suspected of being abused, with ASDH (n = 16) or CSDH (n = 69), were reviewed regarding age, risk factor profiles, craniocortical width (CCW), sinocortical width (SCW), frontal interhemispheric width (IHW), subarachnoid space width (SSW), and head circumference (HC). In infants with unilateral subdural hematoma (SDH), correlations between contralateral SSW and ipsilateral CCW and SDH width were investigated. RESULTS: Infants with CSDH had significantly lower mortality, were more often premature and male, and had significantly higher CCW, SCW, IHW, and SSW than infants with ASDH (P < 0.05). Ipsilateral CCW (R = 0.92, P < 0.001) and SDH width (R = 0.81, P < 0.01) correlated with contralateral SSW. Increased HC was more prevalent in infants with CSDH (71%) than in infants with ASDH (14%) (P < 0.01). Forty-two infants, all with CSDH, had at least one of CCW, SCW, or IHW ≥95th percentile. Twenty infants, all with CSDH, had CCW, SCW, and IHW >5 mm, in addition to increased HC. CONCLUSION: A substantial proportion of infants with CSDH who had been suspected of being abused had findings suggesting external hydrocephalus.

Characteristics of post-mortem beta-hydroxybutyrate-positivet cases - A retrospective study on age, sex and BMI in 1407 forensic autopsies.

BACKGROUND: Post-mortem biochemistry, including the analysis of beta-hydroxybutyrate (BHB), is increasingly employed in forensic medicine, especially in conditions such as diabetes and chronic alcoholism. However, not much is known about the associations between age, body mass index (BMI), and sex and BHB concentrations in ketoacidotic conditions. AIM: To retrospectively study the association between age, BMI and sex in several conditions, such as diabetic ketoacidosis (DKA), alcoholic ketoacidosis (AKA), and elevated post-mortem BHB concentrations. METHODS: 1407 forensic autopsy cases analysed for BHB were grouped by diagnosis: DKA, AKA, HHS [hyperosmolar hyperglycaemic state], acidosis NOS [not otherwise specified], or hypothermia. Age, sex, BMI and the concentrations of blood alcohol, vitreous glucose and blood BHB were recorded. RESULTS: Cases of AKA and DKA were most numerous (184 and 156, respectively). In DKA and in its male subgroup, cases with severe ketosis (BHB>1000 µg/g) were younger and had a lower BMI than those with moderate ketosis (BHB 250-1000 µg/g) and controls (P<0.001). In DKA and in its female subgroup, cases with moderate ketosis cases were older (P = 0.0218 and P = 0.0083) than controls. In AKA and in its male subgroup, cases with severe ketosis had a lower BMI than those with moderate ketosis (P = 0.0391 and P = 0.0469) and controls (P<0.001). Cases with moderate ketosis had a lower BMI than controls (P<0.001). CONCLUSIONS: BHB concentration is associated with BMI in DKA and AKA, and with both BMI and age in DKA. Constitutional factors should, therefore, be considered in potential AKA and DKA cases.

Criminal mutilation in Sweden from 1991 to 2017.

We identified 43 cases of mutilation homicides in a nationwide population-based study in Sweden during the period of 1991-2017. 70% of cases were classified as defensive mutilations where the main motive was disposal of the body, while 30% were classified as offensive, that is, due to an expression of strong aggression, necro-/sexual sadism, or psychiatric illness. In comparison with a previous study covering mutilation homicides in Sweden between 1961 and 1990, we noted an increase in incidence. The percentage of cases involving mutilation had increased from 0.5% of all homicides in the 1960s to 2.4% in the 2010s. The most common cause of death was sharp force, but in 28% of the cases, the cause of death could not be determined. The clearance rate in cases of mutilation homicide was 67%, and in a large majority of the cases, the offender was known to the victim. With regards to gender women made up 44% of the victims, whilst men constituted 56% of the victims and a total of 95% of the offenders. Half of the offenders had a personality disorder, however, only 13% were sentenced to forensic psychiatric care.

A model for evaluating the economic value of prevention programs for illicit use of anabolic androgenic steroids.

BACKGROUND: The illicit use of anabolic androgenic steroids (AAS) has become a societal concern. We developed a decision-analytic model for assessing the cost-effectiveness of preventive interventions targeting AAS-use. We used scenario analyses to demonstrate: a) the potential health economic consequences of AAS use in Sweden, and b) the cost-effectiveness of a hypothetical preventive intervention. METHODS: A population-based cohort model compared a hypothetical preventive intervention targeting AAS with a 'no intervention' scenario, from a limited societal perspective. The model simulated how a cohort of 18 year-old males transitioned between different states and predicted their health status and complications until the age of 41. Health outcomes were estimated as quality-adjusted life-years (QALY). Costs included intervention costs, drug costs, and costs of complications. RESULTS: Total yearly costs related to AAS use amounted to nearly half a million US$, with the largest cost borne by the healthcare sector. Results suggest that AAS prevention could entail large costs and benefits with a mean incremental cost-effectiveness ratio of $550 per QALY, in a scenario where the intervention would decrease the probability of initiating AAS use by 5%. CONCLUSION: Results show large AAS related costs, and suggest that the implementation of a preventive intervention could offer good value for money given different effectiveness scenarios. This model can be used to estimate the value of interventions targeting AAS use.

Rib fractures in infancy, case-series and register case-control study from Sweden.

OBJECTIVES: To assess cases with rib fractures in infants under observation for or with an abuse diagnosis, and to compare risk factors with that in infants with fractures but no abuse diagnosis. METHODS: Design was case-series and register case-control of infants (aged <1 year) with rib fractures. Data was clinical records for the case-series (n = 26) and from national health registers for the case-controls (n = 28 and n = 31). Outcome measures were maternal and perinatal characteristics, reasons for appointment, examination, diagnoses, blood tests, and radiologic findings. RESULTS: The case-series had a median age of 70 days. A majority were detected through a skeletal survey for abuse investigation. Sixteen were boys, three were preterm and six were small-for-gestational age. Three carers had noticed popping sound from the chest; no infants showed signs of pain at physical examination. Mean number of fractures was 4.2, and 24 had callus. Bone mineralisation was scarcely reported. Metabolic panel was not uniformly analysed. The register case-control had a median age of 76 days, sharing risk factors such as maternal overweight/obesity, male sex, prematurity, and being small-for-gestational age. Cases more often had subdural haemorrhage, retinal haemorrhage, or long-bone fractures, controls more often had neonatal morbidity, respiratory infection, or a fall accident. Detection of fracture at time of a major surgery (n = 6) and rickets/vitamin D deficiency (n = 5) appeared in both groups, but was delayed among the cases. CONCLUSIONS: Rib fractures in young infants, diagnosed as abuse, are usually asymptomatic and healing. A substantial proportion had metabolic risk factors, suggesting false positive cases.

The epidemiology of infant shaft fractures of femur or humerus by incidence, birth, accidents, and other causes.

BACKGROUND: The purpose of this population-based registry study was to analyze both birth-related femur and humerus shaft fractures and diagnosed later in infancy, as regards incidence, perinatal characteristics, other diagnoses, and reported accidents. METHODS: Children born in 1997-2014, diagnosed with a femur or humerus shaft fracture before age 1 year, were identified in the Swedish Health Registries. Rate of birth fractures were estimated by combining femur and humerus shaft fractures coded as birth-related with femur and humerus shaft fractures diagnosed during day 1-7 without registered trauma or abuse. Incidence was computed by comparing infants with femur or humerus shaft fractures to the total at-risk population. RESULTS: The incidence for birth-related femur shaft fractures was 0.024 per 1000 children (n = 45) and that for birth-related humerus shaft fractures was 0.101 per 1000 children (n = 188). The incidence was 0.154 per 1000 children for later femur shaft fractures (n = 287) and 0.073 per 1000 children for later humerus shaft fractures (n = 142). Birth-related femur shaft fracture was associated with shoulder dystocia, cesarean, multiple birth, breech, preterm, and small-for-gestational age, while humerus shaft fracture was associated with maternal obesity, dystocic labor, shoulder dystocia, vacuum-assisted delivery, male sex, multiple birth, breech, preterm, large-for-gestational age, birth weight > 4000 g, and injury of brachial plexus. A bone fragility diagnosis was recorded in 5% of those with birth-related or later femur shaft fractures. Among infants with birth-related humerus shaft fractures, 1% had a bone fragility diagnosis; the figure for later fractures was 6%. Maltreatment diagnosis was associated with later fractures of both types, especially among those aged < 6 months, where approximately 20% (femur) and 14% (humerus) of cases, respectively, were associated with abuse. Fall accidents were reported in 73 and 56% among those with later femur and humerus shaft fractures, respectively. CONCLUSION: This study provides data on epidemiology, birth, parental characteristics, and reported accidents in relation to femur and humerus shaft fractures during infancy. Few children had a bone fragility diagnosis. Fall accidents were the main contributor to femur or humerus shaft fracture during infancy; however, the proportion of fractures attributed to maltreatment was high in children under 6 months.

Medical findings and symptoms in infants exposed to witnessed or admitted abusive shaking: A nationwide registry study.

BACKGROUND: Many physicians regard the combination of encephalopathy, subdural haemorrhage (SDH), retinal haemorrhage (RH), rib fractures, and classical metaphyseal lesions (CML) as highly specific for abusive head trauma (AHT). However, without observed abuse or other criteria that are independent of these findings, bias risk is high. METHODS: Infants subjected for examination under the suspicion of maltreatment during the period 1997-2014 were identified in the National Patient Registry, International Classification of Diseases (ICD-10 SE). The medical records were scrutinized for identification of cases of witnessed or admitted physical abuse by shaking. The main outcome measures were occurrence of SDH, RH, fractures and skin lesions. RESULTS: All identified 36 infants had been shaken, and for 6, there was information indicating blunt force impact immediately after shaking. In 30 cases, there were no findings of SDH or RH, rib fractures, or CMLs. Six infants had finding(s) suggestive of physical abuse, two with possible acute intracranial pathology. One infant with combined shaking and impact trauma had hyperdense SDH, hyperdense subarachnoid haemorrhage, suspected cortical vein thrombosis, RH, and bruises. Another infant abused by shaking had solely an acute subarachnoid haemorrhage. Both had pre-existing vulnerability. The first was born preterm and had non-specific frontal subcortical changes. The other had bilateral chronic SDH/hygroma. CONCLUSIONS: The present findings do not support the hypothesis that acute SDH or RH can be caused by isolated shaking of a healthy infant. However, they do suggest that abuse by shaking may cause acute intracranial haemorrhage with RH in infants with certain risk factors.

Difficult birth is the main contributor to birth-related fracture and accidents to other neonatal fractures.

AIM: Specific birth-related fractures have been studied; underestimates might be a problem. We aimed to assess all fractures diagnosed as birth-related as well as other neonatal fractures. METHODS: A population-based study on all infants born in Sweden 1997-2014; data were retrieved from the Swedish Health Registers (10th version of International Classification of Diseases. Outcome measures were birth-related fractures (ICD-10 P-codes) and other neonatal fractures (ICD-10 S-codes). RESULTS: The overall fracture incidence was 2.9 per 1000 live birth (N = 5336); 92.6% had P-codes and 7.4% (S-codes). Some birth-related fractures were diagnosed beyond the neonatal period. Other neonatal fractures could have been birth-related. Clavicle fracture (88.8%) was associated with adverse maternal and infant anthropometrics and birth complications. The few neonates with rib fractures all had concomitant clavicle fracture. For skull fractures, a minor part was birth-related and most were associated with accidents. Half of the long bone fractures were associated with accidents. Birth-related femur fractures were associated with bone fragility risk factors. Five infants with abuse diagnoses had fractures: skull (4), long bone (2) and rib (1). CONCLUSION: Birth-related and other neonatal fractures are rarely diagnosed. Difficult birth is the main contributor to birth-related fracture and accidents to other neonatal fractures.

Association between homicide injury severity and benzodiazepine influence.

There are case reports of offenders inflicting excessive injuries on their victims when under the influence of benzodiazepines. However, the potential association between benzodiazepine influence on the offender and victim injury severity in a general homicide population has not been studied. We investigated associations between offender positive testing for benzodiazepines or z-drugs (zolpidem, zopiclone and zaleplon) and victim injury severity. Data were drawn from 95 Swedish homicide cases from 2007-2009 in which offenders had known toxicology. There were no significant differences in injury severity between cases in which the offender tested positive vs. negative for benzodiazepines/z-drugs. Thus, the findings do not support the hypothesis that there is an association between benzodiazepine influence on the offender and victim injury severity in a general homicide population.Key pointsSome previous studies have linked benzodiazepines to aggression, violence and excessive homicide injuries.The present study analysed the association between homicide injury severity and benzodiazepine status of the offender.Offenders who tested positive for benzodiazepines did not inflict more severe injuries on their victims.These findings do not support the hypothesis that benzodiazepine influence generally causes offenders to inflict more severe injuries on homicide victims.

Drug-related deaths: Statistics based on death certificates miss one-third of cases.

Aims: Statistics on drug-related deaths (DRD) provide crucial information on the drug situation. The European Monitoring Centre for Drug and Drug Addiction (EMCDDA) has published a specification for extracting DRD from national mortality registers to be used in international comparisons. However, surprisingly little is known of the accuracy of DRD statistics derived from national mortality registers. This study assesses the accuracy of Swedish data derived from national mortality registers by comparing it with other sources of data. Methods: We compared five Swedish datasets. Three were derived from national mortality registers, two according to a Swedish specification and one according to the EMCDDA specification. A fourth dataset was based on toxicological analyses. We used a fifth dataset, an inventory of DRD in Stockholm, to assess the completeness and coverage of the Swedish datasets. Results: All datasets were extracted from high-quality registers, but still did not capture all DRD, and both the numbers and demographic characteristics varied considerably. However, the time trends were consistent between the selections. In international comparisons, data completeness and investigation procedures may impact even more on stated numbers. Conclusions: Basing international comparisons on numbers or rates of DRDs gives misleading results, but comparing trends is still meaningful.

Medical diagnoses among infants at entry in out-of-home care: A Swedish population-register study.

BACKGROUND AND AIMS: Identification of child abuse involves a medical investigation and assessment of problems related to social environment and upbringing and might necessitate out-of-home care. The objective of this study was to analyse infants placed in out-of-home care in Sweden by incidence, medical diagnoses, and perinatal factors. METHODS: This was a population-based register study of infants born in Sweden 1997 to 2014. Data were retrieved from registers at the Swedish National Board of Health and Welfare and Statistics Sweden. Outcome measures were out-of-home care categories: (a) "Problems Related to Social Environment/Upbringing", (b) "Abuse diagnoses without SDH (subdural haemorrhage), RH (retinal haemorrhage), rib fracture, or long bone fracture", and (c) "SDH, RH, rib fracture, or long bone fracture." As a reference population, we randomly selected infants without medical diagnoses born the same year. RESULTS: Overall incidence of out-of-home care was 402 per 100 000. For subcategories (a), (b), and (c), the incidences were 14.8 (n = 273), 3.77 (n = 70), and 9.83 (n = 182) per 100 000, respectively. During the study period, the first remained unchanged; the latter two have been increasing. Compared with other reasons for out-of-home care, children in category (c), "SDH, RH, rib fracture, or long bone fracture", had increased odds of being boys (adjusted odds ratio [aOR] 1.60; 95% confidence interval [CI], 1.08-2.38) and decreased odds of having a mother being single (aOR 0.49; 95% CI, 0.32-0.75) and a smoker (aOR 0.60; 95% CI, 0.37-0.96). Compared with the reference population, children in this category were more often twin born (7.7% versus 2.8%), preterm (18.5% versus 5.5%), and small-for-gestational age (5.2% versus 2.1%). CONCLUSION: SDH, RH, rib fracture, or long bone fracture constitute a minor part of medical diagnoses for infants entered in out-of-home care, but have been increasing, both in numbers and proportion. Overdiagnosis of abuse might be a possible reason but cannot be ascertained by this study design.