A predictive model for perinatal hypoxic ischemic encephalopathy using linked maternal and neonatal hospital data.

PURPOSE: To build an evidence-based model to estimate case-specific risk of perinatal hypoxic ischemic encephalopathy. METHODS: A retrospective, cross-sectional study of all births in Hawaii, Michigan, and New Jersey between 2010 and 2015, using linked maternal labor/delivery and neonatal birth records. Stepwise logistic regression and competitive Akaike information criterion were used to identify the most parsimonious model. Predictive ability of the model was measured with bootstrapped optimism-adjusted area under the ROC curve. RESULTS: Among 836,216 births there were 376 (0.45 per 1000) cases of hypoxic ischemic encephalopathy. The final model included 28 variables, 24 associated with increased risk, and 4 that were protective. The optimism-adjusted area under the ROC curve was 0.84. Estimated risk in the study population ranged from 1 in ∼323,000 to 1 in 2.5. The final model confirmed known risk factors (e.g., sentinel events and shoulder dystocia) and identified novel risk factors, such as maternal race and insurance status. CONCLUSION: Our study shows that risk of perinatal hypoxic ischemic encephalopathy injury can be estimated with high confidence. Our model fills a notable gap in the study of hypoxic ischemic encephalopathy prevention: the estimation of risk, particularly in the United States population which is unique with respect to racial and socioeconomic disparities.

Injuries Due to Law Enforcement Use of Force in the United States, 2006-2015: Trends in Severity and by Race.

PURPOSE: The purpose of the study was to assess incidence and severity of hospital reported injuries related to law enforcement Use of Force (UoF) in the US over time, and by race. METHODS: Data from the National Emergency Department Sample from the Healthcare Cost and Utilization Project and the National Electronic Injury Surveillance System (NEISS-AIP) from US Consumer Product Safety Commission were queried to identify UoF injuries. Regression analysis, t-tests, and chi-square tests were used in the analysis. RESULTS: Between 2006-15, there were 529,259 emergency department admissions for UoF injury in the NEDS, and 870,779 admissions in the NEISS-AIP. In a model adjusting for year, sex, and age, the Injury Severity Score increased by 1.1% annually (p<0.0001). Black people were 6 times as likely to be admitted to the ED as White people or Native Americans/Alaska Natives, and 25 times as likely as Asians/Pacific Islanders. Black patients were 4 times as likely as White patients to be admitted as inpatients. Per arrest rate by race using FBI uniform crime reporting data, Black arrestees were 2.5-3.1 times as likely as any other race to be hospitalized for UoF injury. CONCLUSION: The results of the study demonstrate that US law enforcement are injuring civilians more frequently and severely over time, and that Black people are disproportionately affected.

Response to "Scrutinizing the causal link between excited delirium syndrome and restraint - a commentary on: 'The role of restraint in fatal excited delirium: a research synthesis and pooled analysis' by E.M.F. Strömmer, W. Leith, M.P. Zeegers and M.D. Freeman".

de Boer et al. criticize the conclusions in our 2020 paper on the validity of Excited Delirium Syndrome (ExDS) as "egregiously misleading." Our conclusion was that there "is no existing evidence that indicates that ExDS is inherently lethal in the absence of aggressive restraint." The basis for de Boer and colleague's criticism of our paper is that the ExDS literature does not provide an unbiased view of the lethality of the condition, and therefore the true epidemiologic features of ExDS cannot be determined from what has been published. The criticism is unrelated to the goals or methods of the study, however. Our stated purpose was to investigate "how the term ExDS has evolved in the literature and been endowed with a uniquely lethal quality," and whether there is "evidence for ExDS as a unique cause of a death that would have occurred regardless of restraint, or a label used when a restrained and agitated person dies, and which erroneously directs attention away from the role of restraint in explaining the death." We cannot fathom how de Boer et al. missed this clearly stated description of the study rationale, or why they would endorse a series of fallacious and meaningless claims that gave the appearance that they failed to grasp the basic design of the study. We do acknowledge and thank these authors for pointing out 3 minor citation errors and an equally minor table formatting error (neither of which altered the reported results and conclusions in the slightest), however.

Non-Surgical Management of Upper Cervical Instability via Improved Cervical Lordosis: A Case Series of Adult Patients.

Injury to the head and neck resulting from whiplash trauma can result in upper cervical instability (UCIS), in which excessive movement at C1 on C2 is observed radiologically. In some cases of UCIS there is also a loss of normal cervical lordosis. We postulate that improvement or restoration of the normal mid to lower cervical lordosis in patients with UCIS can improve the biomechanical function of the upper cervical spine, and thus potentially improve symptoms and radiographic findings associated with UCIS. Nine patients with both radiographically confirmed UCIS and loss of cervical lordosis underwent a chiropractic treatment regimen directed primarily at the restoration of the normal cervical lordotic curve. In all nine cases, significant improvements in radiographic indicators of both cervical lordosis and UCIS were observed, along with symptomatic and functional improvement. Statistical analysis of the radiographic data revealed a significant correlation (R2 = 0.46, p = 0.04) between improved cervical lordosis and reduction in measurable instability, determined by C1 lateral mass overhang on C2 with lateral flexion. These observations suggest that enhancing cervical lordosis can contribute to improvement in signs and symptoms of upper cervical instability secondary to traumatic injury.

Post-Traumatic Atlanto-Axial Instability: A Combined Clinical and Radiological Approach for the Diagnosis of Pathological Rotational Movement in the Upper Cervical Spine.

Post-traumatic rotational instability at the atlanto-axial (C1-2) joint is difficult to assess, much less quantify, due to the orientation and motion plane of the joint. Prior investigations have demonstrated that a dynamic axial CT scan, during which the patient maximally rotates the head right and left, can be used to evaluate and quantify the amount of residual overlap between the inferior articulating facet of C1 and the superior facet of C2, as an index of ligamentous laxity at the joint. We have previously demonstrated that a novel orthopedic test of rotational instability, the atlas-axis rotational test (A-ART), may have utility in identifying patients with imaging evidence of upper cervical ligament injury. In the present investigation, we assessed the correlation between a positive A-ART and a CT scan assessment of the relative quantity of residual C1-2 overlap, as a percent of the superior articulating facet surface area of C2. A retrospective review was conducted of the records of consecutive patients presenting to a physical therapy and rehabilitation clinic, over a 5-year period (2015-20) for chronic head and neck pain after whiplash trauma. The primary inclusion criteria were that the patient had undergone both a clinical evaluation with A-ART and a dynamic axial CT to evaluate for C1-2 residual facet overlap at maximum rotation. The records for a total of 57 patients (44 female/13 male) were identified who fit the selection criteria, and among these, there were 43 with a positive A-ART (i.e., "cases") and 14 with a negative A-ART (i.e., "controls). The analysis demonstrated that a positive A-ART was highly predictive of decreased residual C1-2 facet overlap: the average overlap area among the cases was approximately one-third that of the control group (on the left, 10.7% versus 29.1%, and 13.6% versus 31.0% on the right). These results suggest that a positive A-ART is a reliable indicator of underlying rotational instability at C1-2 in patients with chronic head and neck symptoms following whiplash trauma.

Principles and Methods for Evidence-Based Quantification of the Effect of Seat Belt Non-Use in Crash-Related Litigation.

Traffic crashes are a common cause of injury and death, and often result from the negligent actions of an inattentive, speeding, or impaired driver. In such cases, a civil legal action may be brought by an injured claimant for compensation for injuries resulting from a crash. Crash-related litigation is defended on various theories, one of which is to raise the issue of contributory negligence when the claimant was not using an available seat belt at the time of the crash, based on the assertion that the claimed injuries would have been avoided or minimized to some degree if the claimant had been restrained. At present, there are no published standards or systematic approach for assessing and quantifying the contribution of seat belt non-use to the cause of a claimant's specific injury. A reliable medicolegal analysis that addresses whether contributory negligence can be proven in a specific case requires a multidisciplinary approach: First, the nature and severity of the crash must be reconstructed as it affected the vehicle kinetics (engineering) and in turn affected the kinematics of the occupant (biomechanics), next, the injuries must be described and scaled for severity (medicine/pathology), and finally, the risk of the known injuries given the actual circumstances of the crash and occupant (i.e., unbelted) are compared to the risk of the same injuries, and the same crash circumstances, but in the hypothetical scenario in which the claimant is belted. In the present discussion, methods for analyzing the presence and quantifying the degree of contributory negligence for seat belt non-use, suitable for presentation in a medicolegal setting, are described and illustrated with an example from the author's personal case inventory. A detailed reconstruction of the crash is described, along with the associated occupant kinematics, and the resulting observed injuries. The injuries are then categorized by their anatomical location, type, and severity using Abbreviated Injury Scale designations. Quantification of the injury risk for the actual (unbelted) vs. hypothetical (belted) scenario is based on case-specific analysis of data accessed from a US national crash injury database The difference in risk for the two exposure scenarios can be quantified in terms of either relative risk (a risk ratio) or attributable risk (a risk proportion), with the goal to determine whether the analysis meets the threshold of a relative risk of >2.0, or an attributable risk of 50%, in order to meet the "more probable than not" standard typically required by courts. As a final step in a reliable analysis that exceeds the legal threshold for relevant evidence, the absolute increase in risk is used to quantify the degree to which the claimant's seat belt non-use contributed to the likelihood of their injuries.

Medicolegal Causation Investigation of Bacterial Endocarditis Associated with an Oral Surgery Practice Using the INFERENCE Approach.

Investigating causation is a primary goal in forensic/legal medicine, aiming to establish the connection between an unlawful/negligent act and an adverse outcome. In malpractice litigation involving a healthcare-associated infection due to a failure of infection prevention and control practices, the medicolegal causal analysis needs to quantify the individual causal probabilities to meet the evidentiary requirements of the court. In this paper, we present the investigation of the most probable cause of bacterial endocarditis in a patient who underwent an invasive procedure at a dental/oral surgical practice where an outbreak of bacterial endocarditis had already been identified by the state Department of Health. We assessed the probability that the patient's endocarditis was part of the outbreak versus that it was an unrelated sporadic infection using the INFERENCE (Integration of Forensic Epidemiology and the Rigorous Evaluation of Causation Elements) approach to medicolegal causation analysis. This paper describes the step-by-step application of the INFERENCE approach to demonstrate its utility in quantifying the probability of causation. The use of INFERENCE provides the court with an evidence-based, transparent, and reliable guide to determine liability, causation, and damages.

Is Acceleration a Valid Proxy for Injury Risk in Minimal Damage Traffic Crashes? A Comparative Review of Volunteer, ADL and Real-World Studies.

Injury claims associated with minimal damage rear impact traffic crashes are often defended using a "biomechanical approach," in which the occupant forces of the crash are compared to the forces of activities of daily living (ADLs), resulting in the conclusion that the risk of injury from the crash is the same as for ADLs. The purpose of the present investigation is to evaluate the scientific validity of the central operating premise of the biomechanical approach to injury causation; that occupant acceleration is a scientifically valid proxy for injury risk. Data were abstracted, pooled, and compared from three categories of published literature: (1) volunteer rear impact crash testing studies, (2) ADL studies, and (3) observational studies of real-world rear impacts. We compared the occupant accelerations of minimal or no damage (i.e., 3 to 11 kph speed change or "delta V") rear impact crash tests to the accelerations described in 6 of the most commonly reported ADLs in the reviewed studies. As a final step, the injury risk observed in real world crashes was compared to the results of the pooled crash test and ADL analyses, controlling for delta V. The results of the analyses indicated that average peak linear and angular acceleration forces observed at the head during rear impact crash tests were typically at least several times greater than average forces observed during ADLs. In contrast, the injury risk of real-world minimal damage rear impact crashes was estimated to be at least 2000 times greater than for any ADL. The results of our analysis indicate that the principle underlying the biomechanical injury causation approach, that occupant acceleration is a proxy for injury risk, is scientifically invalid. The biomechanical approach to injury causation in minimal damage crashes invariably results in the vast underestimation of the actual risk of such crashes, and should be discontinued as it is a scientifically invalid practice.

The role of restraint in fatal excited delirium: a research synthesis and pooled analysis.

The purpose of the present study was to perform a comprehensive scientific literature review and pooled data risk factor analysis of excited delirium syndrome (ExDS) and agitated delirium (AgDS). All cases of ExDS or AgDS described individually in the literature published before April 23, 2020 were used to create a database of cases, including demographics, use of force, drug intoxication, mental illness, and survival outcome. Odds ratios were used to quantify the association between death and diagnosis (ExDS vs. AgDS) across the covariates. There were 61 articles describing 168 cases of ExDS or AgDS, of which 104 (62%) were fatal. ExDS was diagnosed in 120 (71%) cases, and AgDS in 48 (29%). Fatalities were more likely to be diagnosed as ExDS (OR: 9.9, p < 0.0001). Aggressive restraint (i.e. manhandling, handcuffs, and hobble ties) was more common in ExDS (ORs: 4.7, 14, 29.2, respectively, p < 0.0001) and fatal cases (ORs: 7.4, 10.7, 50, respectively, p < 0.0001). Sedation was more common in AgDS and survived cases (OR:11, 25, respectively, p < 0.0001). The results of the study indicate that a diagnosis of ExDS is far more likely to be associated with both aggressive restraint and death, in comparison with AgDS. There is no evidence to support ExDS as a cause of death in the absence of restraint. These findings are at odds with previously published theories indicating that ExDS-related death is due to an occult pathophysiologic process. When death has occurred in an aggressively restrained individual who fits the profile of either ExDS or AgDS, restraint-related asphyxia must be considered a likely cause of the death.

Exposure to a motor vehicle collision and the risk of future back pain: A systematic review and meta-analysis.

OBJECTIVE: The purpose of this study is to summarize the evidence for the association between exposure to a motor vehicle collision (MVC) and future low back pain (LBP). LITERATURE SURVEY: Persistent low back pain (LBP) is a relatively common complaint after acute injury in a MVC, with a reported 1 year post-crash prevalence of at least 31 % of exposed individuals. Interpretation of this finding is challenging given the high incidence of LBP in the general population that is not exposed to a MVC. Risk studies with comparison control groups need to be examined in a systematic review. METHODOLOGY: A systematic search of five electronic databases from 1998 to 2019 was performed. Eligible studies describing exposure to a MVC and risk of future non-specific LBP were critically appraised using the Quality in Prognosis Studies (QUIPS) instrument. The results were summarized using best-evidence synthesis principles, a random effects meta-analysis and testing for publication bias. SYNTHESIS: The search strategy yielded 1136 articles, three of which were found to be at low to medium risk of bias after critical appraisal. All three studies reported a positive association between an acute injury in a MVC and future LBP. Pooled analysis of the results resulted in an unadjusted relative risk of future LBP in the MVC-exposed and injured population versus the non-exposed population of 2.7 (95 % CI [1.9, 3.8]), which equates to a 63 % attributable risk under the exposed. CONCLUSIONS: There was a consistent positive association in the critically reviewed literature that investigated the risk of future LBP following an acute MVC-related injury. For the patient with chronic low back pain who was initially injured in a MVC, more often than not (63 % of the time) the condition was caused by the MVC. These findings are likely to be of interest to clinicians, insurers, patients, governments and the courts. Future studies from both general and clinical populations would help strengthen these results.

Estimating the number of traffic crash-related cervical spine injuries in the United States; An analysis and comparison of national crash and hospital data.

BACKGROUND: Cervical spine injury is a common result of traffic crashes, and such injuries range in severity from minor (i.e. sprain/strain) to moderate (intervertebral disk derangement) to serious and greater (fractures, dislocations, and spinal cord injuries). There are currently no reliable estimates of the number of crash-related spine injuries occurring in the US annually, although several publications have used national crash injury samples as a basis for estimating the frequency of both cervical and lumbar spinal disk injuries occurring in lower speed rear impact crashes. PURPOSE: To develop a reliable estimate of the number of various types of cervical spine injuries occurring in the US by comparing data from national crash injury to national hospital ED and inpatient samples. STUDY DESIGN: Comparative cross-sectional METHODS: Cervical spine injury data were accessed, analyzed, and compared from 3 national databases; the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS), Nationwide Emergency Department Sample (NEDS), and the Nationwide Inpatient Sample (NIS). RESULTS: It is estimated that there are approximately 869,000 traffic crash-related cervical spine injuries seen in hospitals in the US annually, including around 841,000 sprain/strain (whiplash) injuries, 2800 spinal disk injuries, 23,500 fractures, 2800 spinal cord injuries, and 1500 dislocations. Because of a highly restrictive inclusion criteria for both crash and injury types, as well as a very small sample size, the NASS-CDS underestimated all types of crash-related cervical spine injuries seen in US hospital emergency departments by 84 %. The injury type with the largest degree of underestimation in the NASS-CDS was cervical disk injuries, which were estimated at an 88 % lower frequency than in the NEDS. National insurance claim data, which include cases of cervical disk injury diagnosed both in and outside of the ED, indicate that the NEDS likely undercounts cervical disk injuries by 92 %, and thus the NASS-CDS correspondingly undercounts such injuries by 99 % or more. CONCLUSIONS: Because of a limited sample size and restrictive criteria for both crash and injury inclusion, the NASS-CDS cannot be used to estimate the number of crash-related spinal injuries of any type or severity in the US. The most inappropriate use of the database is for estimating the number of spinal injuries resulting from low speed rear impact collisions, as the NASS-CDS samples fewer than 1 in 100,000 of the cervical spine injuries of any type occurring in low speed rear impact collisions.

Diagnostic Accuracy of Videofluoroscopy for Symptomatic Cervical Spine Injury Following Whiplash Trauma.

BACKGROUND: Intervertebral instability is a relatively common finding among patients with chronic neck pain after whiplash trauma. Videofluoroscopy (VF) of the cervical spine is a potentially sensitive diagnostic tool for evaluating instability, as it offers the ability to examine relative intervertebral movement over time, and across the entire continuum of voluntary movement of the patient. At the present time, there are no studies of the diagnostic accuracy of VF for discriminating between injured and uninjured populations. METHODS: Symptomatic (injured) study subjects were recruited from consecutive patients with chronic (>6 weeks) post-whiplash pain presenting to medical and chiropractic offices equipped with VF facilities. Asymptomatic (uninjured) volunteers were recruited from family and friends of patients. An ethical review and oversight were provided by the Spinal Injury Foundation, Broomfield, CO. Three statistical models were utilized to assess the sensitivity, specificity, positive and negative predictive values (PPV and NPV) of positive VF findings to correctly discriminate between injured and uninjured subjects. RESULTS: A total of 196 subjects (119 injured, 77 uninjured) were included in the study. All three statistical models demonstrated high levels of sensitivity and specificity (i.e., receiver operating characteristic (ROC) values of 0.71 to 0.95), however, the model with the greatest practical clinical utility was based on the number of abnormal VF findings. For 2+ abnormal VF findings, the ROC was 0.88 (93% sensitivity, 79% specificity) and the PPV and NPV were both 88%. The highest PPV (1.0) was observed with 4+ abnormal findings. CONCLUSIONS: Videofluoroscopic examination of the cervical spine provides a high degree of diagnostic accuracy for the identification of vertebral instability in patients with chronic pain stemming from whiplash trauma.

A review of causal inference in forensic medicine.

The primary aim of forensic medical analysis is to provide legal factfinders with evidence regarding the causal relationship between an alleged action and a harmful outcome. Despite existing guides and manuals, the approach to formulating opinions on medicolegal causal inference used by forensic medical practitioners, and how the strength of the opinion is quantified, is mostly lacking in an evidence-based or systematically reproducible framework. In the present review, we discuss the literature describing existing methods of causal inference in forensic medicine, especially in relation to the formulation of expert opinions in legal proceedings, and their strengths and limitations. Causal inference in forensic medicine is unique and different from the process of establishing a diagnosis in clinical medicine. Because of a lack of tangibility inherent in causal analysis, even the term "cause" can have inconsistent meaning when used by different practitioners examining the same evidence. Currently, there exists no universally applied systematic methodology for formulating and assessing causality in forensic medical expert opinions. Existing approaches to causation in forensic medicine generally fall into two categories: intuitive and probabilistic. The propriety of each approach depends on the individual facts of an investigated injury, disease, or death. We opine that in most forensic medical settings, probabilistic causation is the most suitable for use and readily applicable. Forensic medical practitioners need, however, be aware of the appropriate approach to causation for different types of cases with varying degrees of complexity.

Exposure to a Motor Vehicle Collision and the Risk of Future Neck Pain: A Systematic Review and Meta-Analysis.

OBJECTIVE: To summarize the literature that has examined the association between a motor vehicle collision (MVC) related neck injury and future neck pain (NP) in comparison with the population that has not been exposed to neck injury from an MVC. LITERATURE SURVEY: Neck injury resulting from an MVC is associated with a high rate of chronicity. Prognosis studies indicate 50% of injured people continue to experience NP a year after the collision. This is difficult to interpret due to the high prevalence of NP in the general population. METHODOLOGY: We performed a systematic review of the literature using five electronic databases, searching for risk studies on exposure to an MVC and future NP published from 1998 to 2018. The outcome of interest was future NP. Eligible risk studies were critically appraised using the modified Quality in Prognosis Studies (QUIPS) instrument. The results were summarized using best-evidence synthesis principles, a random effects meta-analysis, metaregression, and testing for publication bias was performed with the pooled data. SYNTHESIS: Eight articles were identified of which seven were of lower risk of bias. Six studies reported a positive association between a neck injury in an MVC and future NP compared to those without a neck injury in an MVC. Pooled analysis of the six studies indicated an unadjusted relative risk of future NP in the MVC exposed population with neck injury of 2.3 (95% CI [1.8, 3.1]), which equates to a 57% attributable risk under the exposed. In two studies where exposed participants were either not injured or injury status was unknown, there was no increased risk of future NP. CONCLUSIONS: There was a consistent positive association among studies that have examined the association between MVC-related neck injury and future NP. These findings are of potential interest to clinicians, insurers, patients, governmental agencies, and the courts. LEVEL OF EVIDENCE: I.

The association between gabapentin and suicidality in bipolar patients.

The aims of this study were to assess the association between gabapentin and suicidality in patients diagnosed with bipolar disorder (BD) and to determine whether the risk is greater relative to patients prescribed lithium. This retrospective observational study utilizes US population-based claims data assembled by PharMetrics Inc., comprising 47 918 patients diagnosed with BD. Patients were included if they were at least 18 years old and initiated a new monotherapy prescription of either gabapentin (n=2421) or lithium (n=3101). Patients were followed for up to 1 year. Gabapentin patients contributed 915.8 person-years (PY) of follow-up time; lithium patients contributed 1421.3 PY. There were 21 suicide/self-harm events in the gabapentin group and 16 in the lithium group. Unadjusted incidence rates were 22.9 and 11.3/1000 PY in the gabapentin and lithium groups, respectively (P=0.03). After adjusting for concomitant medications, comorbid diagnoses, age, sex, and history of suicide/self-harm, the hazard ratio was 2.3 (95% confidence interval: 1.2-4.5). A propensity score-matched analysis accounting for pre-existing illnesses and medications supports this finding, with an adjusted hazard ratio of 2.1 (95% confidence interval: 1.02-4.5). Relative to lithium, the use of gabapentin is significantly associated with a doubling of the risk of suicidality in patients diagnosed with BD.

A review of the diversity in taxonomy, definitions, scope, and roles in forensic medicine: implications for evidence-based practice.

The scope, roles, and tasks of forensic medicine and forensic medical experts currently vary widely between countries and legal systems, which has resulted in barriers to organization, standard setting, and quality assurance for practice in forensic medicine, including for reporting. The legal fact finder is thus confronted with variability in the quality, structure, and content of forensic medical reports. We sought to define and categorize the scope, methods, and practices that fall under the description of forensic medicine, the various issues encountered in current forensic medical practice, and the potential role of evidence-based practice in forensic medicine. We searched electronic databases and reviewed relevant articles, as well as conducting personal correspondences with forensic medical practitioners around the world, to obtain a description of current forensic medical practice. The terms forensic medicine, legal medicine, medical jurisprudence, medico-legal services, forensic pathology, and clinical forensic medicine are used with mixed interpretations in different countries. The systems and services rendered are not uniform either. The methods used by forensic medical practitioners are not always evidence-based, or based on standardized methods, and vary greatly between experts and centers. There are also no universally accepted guidelines to prepare a standard and admissible report. The lack of a uniform system in forensic medicine creates difficulties in assessing the development and performance of forensic medicine as a distinct discipline. To prepare evidence-based forensic medical reports, generally accepted guidelines are necessary.

Central Sensitization Is Modulated Following Trigger Point Anesthetization in Patients with Chronic Pain from Whiplash Trauma. A Double-Blind, Placebo-Controlled, Crossover Study.

Objective: Central sensitization (CS) with low peripheral pain thresholds (PPTs) is a common finding among patients with chronic pain after whiplash (CPWI). While it has been proposed that myofascial myofascial trigger points (MTrPs) may act as modulators of central sensitization, previously reported findings are conflicting and inconclusive. The present study was designed to investigate immediate responsiveness of CS to alterations in nociceptive input. Design: Controlled, double-blind, cross-over. Subjects: Thirty-one patients with chronic pain (trapezius myalgia) and CS after whiplash. Methods: Participants were referred by randomization to group A for injection of a single peripheral pain generator (MTrP or other discrete tender point) with local anesthetic or to group B for sham injection and cross-over. Documentation of PPT (Algometer), maximum jaw opening (caliper), and grip strength (Vigorimeter), as well as subjective overall pain (visual analog scale [VAS]), was made before and after each intervention. Results: Statistical analysis of data (Student's t test, analysis of variance) confirmed that peripheral pain thresholds were significantly higher and maximum jaw opening significantly greater after anesthetizing a focal pain generator in the trapezius, but not after a sham injection. In contrast with the objective variables, subjective generalized pain improved (VAS) after not only an injection of local anesthetic, but also, and to a similar extent, after a sham injection. Conclusions: CS, as expressed by lowered PPT, is a rapidly adjusting physiological response to nociceptive stimuli in some patients with chronic pain after whiplash. PPT are likely modulated by myofascial tender points in selected patients with CS. With reference to the present findings, surgical ablation of MTrPs is discussed as a potential treatment modality for CS.

Exposure to Genocide as a Risk Factor for Homicide Perpetration in Rwanda: A Population-Based Case-Control Study.

A population-based case-control study was conducted to assess the relationship between genocide exposure and homicide perpetration in Rwanda. A sample of 150 homicide perpetrators who were charged with and confessed to having committed homicide between 1 May 2011 and 31 May 2013 and 450 controls were enrolled. Cases were matched to controls by neighborhood, age and sex. Socio-demographic, background and genocide-related information was collected from study subjects' next of kin. Four characteristics of genocide exposure were: genocide survivor, genocide perpetrator, having lost a first-degree relative to genocide and having a first-degree relative convicted of genocide. We assessed the impact of each genocide-exposure variable using conditional logistic regression. Of the 150 cases, 124 (82.7%) were male and 26 (17.3%) were female. The mean age of the alleged homicide perpetrators was 33 years, with a peak in the age group 20-29 years (39.3%). After adjusting for socio-demographic characteristics and past common criminal records, having a first-degree relative who had been convicted of genocide crimes was a significant predictor for homicide perpetration (odds ratio [OR] = 14.4, 95% confidence interval [CI] = 1.6-129.4). Being a genocide perpetrator, a genocide survivor and having lost a first-degree family member to genocide were not identified as risk factors for homicide perpetration. In Rwanda, young people who experienced early exposure to trauma by witnessing their first-degree relatives' active participation in the genocide, are more likely to commit homicide. Socio-economic and psychotherapeutic programs targeting this population group are needed to rehabilitate these young people for violent behavior change.