Papers by Michael Freeman
Annals of Epidemiology, 2024
To build an evidence-based model to estimate case-specific risk of perinatal hypoxic ischemic enc... more 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 optimismadjusted 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.
Forensic Science, Medicine and Pathology
de Boer et al. criticize the conclusions in our 2020 paper on the validity of Excited Delirium Sy... more 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 ...
Pain Research and Management, 2005
BACKGROUND: Minor impact soft tissue (MIST) is an insurance industry concept that seeks to identi... more BACKGROUND: Minor impact soft tissue (MIST) is an insurance industry concept that seeks to identify late whiplash as a psychosocial phenomenon. However, the medical literature in this area has not been systematically reviewed since the Quebec Task Force's review in 1995.OBJECTIVE: To review the medical literature which claims that late whiplash is an organic phenomenon causing significant disability.METHODS: The medical literature was reviewed in a narrative format.RESULTS: There are a significant number of studies which refute the MIST concept.CONCLUSIONS: A review of the literature did not support the validity of MIST.
Pain Research and Management, 2006
The authors undertook a case-control study of chronic neck pain and whiplash injuries in nine sta... more The authors undertook a case-control study of chronic neck pain and whiplash injuries in nine states in the United States to determine whether whiplash injuries contributed significantly to the population of individuals with chronic neck and other spine pain.Four hundred nineteen patients and 246 controls were randomly enrolled. Patients were defined as individuals with chronic neck pain, and controls as those with chronic back pain. The two groups were surveyed for cause of chronic pain as well as demographic information. The two groups were compared using an exposure-odds ratio. Forty-five per cent of the patients attributed their pain to a motor vehicle accident. An OR of 4.0 and 2.1 was calculated for men and women, respectively.Based on the results of the present study, it reasonable to infer that a significant proportion of individuals with chronic neck pain in the general population were originally injured in a motor vehicle accident.
Accuracy-the degree of closeness of quantitative measurements made with a measuring system to the... more Accuracy-the degree of closeness of quantitative measurements made with a measuring system to the quantity's true value. AIS-Abbreviated Injury Scale Association-The statistical relationship between events or variables. If the events occur more or less frequently together than one would expect by random chance then they are considered to be associated. Associations are not necessarily causal, however. ATD-Anthropomorphic Test Device; a crash test dummy Bayes' Theorem (alternatively Bayes' Law)-A method of revising or "conditioning" the probability of the occurrence of an event given the occurrence or non-occurrence of an associated event or events. Bias-In epidemiology bias refers to a form of error that may threaten the validity of a study by producing results that are systematically different than the true results. Two main categories of bias in epidemiologic studies are selection bias, which occurs when study subjects are selected as a result of another unmeasured variable that is associated with both the exposure and outcome of interest; and information bias, which is systematic error in the assessment of a variable. Biomechanics-The field of study pertaining to how force affects tissue. BMI-Body Mass Index, calculated by (weight in kg/(height in meters) 2) Case-control study-A retrospective study design that starts with the identification of persons with a particular disease or injury and compares them with a control group of persons without the same disease or injury for exposures of interest. The results are presented in the form of odds ratios. Causation-The relationship between an antecedent event, condition, characteristic, or agent that produces a disease or injury outcome. General causation is concerned with the cause of disease and injury in populations, and the proportion of the ill or injured population attributable to the exposure. Specific causation is concerned with the cause of disease and injury in individuals, and the probability that the condition would be present absent the exposure to the hazard. Specific causation is quantified by the assessment of the relative risk of cause, in which the hazard rate associated with the exposure of interest is compared with the base rate of the condition occurring at the same point in time absent the exposure. CNS-Central Nervous System, the brain and the spinal cord Cohort study-A study that starts with the identification of persons who have been exposed to a suspected cause of injury or disease, and compares them to an unexposed group of persons for 8 rate of occurrence of the disease or injury. The results are presented in the form of risk ratios.
Scandinavian Journal of Forensic Science, 2020
Motorcycle- and moped crashes are prevalent in motorised societies and carry a significant risk o... more Motorcycle- and moped crashes are prevalent in motorised societies and carry a significant risk of serious injury. Whereas helmet use has reduced the frequency and severity of head injuries, the association between helmet use and neck injury risk is less clear. In the present retrospective study, we examined the relationship between helmet use and various types of head and neck injuries resulting from fatal motorcycle and moped crashes during a 20-year period. Eighty-three cases were included of whom 56 were analysed in detail based on their confirmed use/non-use of helmet. Intracranial haemorrhage was the most common finding, followed by CNS disruption and skull fracture. There was a significantly lower prevalence of skull vault fractures and epidural haemorrhage in the helmeted cases. Injuries to the brainstem and cervical spine fracture/dislocation were more common in the helmeted cases, although this was likely a function of higher speeds among motorcycle riders rather than an e...
Pain Physician, 2008
Background: Baker’s cysts are commonly encountered in pain management practices. Objective: To as... more Background: Baker’s cysts are commonly encountered in pain management practices. Objective: To ascertain if sclerotherapy treatment of a Baker’s cyst could produce objectively verifiable MRI imaging changes. Design: Case report. Methods: A 52-year-old white male with a posterior horn of the medial meniscus tear and a large Baker’s cyst who had failed conservative care and drainage was imaged before treatment with sclerosing. Three injections of 12.5% dextrose and anesthetic with sodium morrhuate were injected intraarticular into the right knee after drainage. Results: The Baker’s cyst resolved on both postoperative imaging after the completion of care as well as on physical examination. Conclusions: Prolotherapy in this case study seemed to be an effective treatment for Baker’s cyst in this patient. Key words: sclerosing, Baker’s cyst, knee, sclerotherapy, sodium morrhuate, dextrose
Forensic Science, Medicine and Pathology, 2020
The purpose of the present study was to perform a comprehensive scientific literature review and ... more 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...
Forensic Science, Medicine and Pathology, 2020
The primary aim of forensic medical analysis is to provide legal factfinders with evidence regard... more 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 evidenc...
PM&R, 2019
Objective: To summarize the literature that has examined the association between a motor vehicle ... more 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.
Forensic Science, Medicine and Pathology, 2018
The scope, roles, and tasks of forensic medicine and forensic medical experts currently vary wide... more 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.
Journal of translational medicine, Jan 3, 2018
Bone marrow concentrate (BMC) has shown promise in the treatment of several orthopedic conditions... more Bone marrow concentrate (BMC) has shown promise in the treatment of several orthopedic conditions. This registry study investigated the use of autologous BMC and platelet products for percutaneous anterior cruciate ligament (ACL) treatment. Twenty-nine patients presenting to a single outpatient interventional musculoskeletal and pain practice with symptomatic grade 1, 2, or 3 ACL tears with less than 1 cm retraction were enrolled. Patients were treated with a percutaneous ACL injection of autologous BMC and platelet products using fluoroscopic guidance. Pre- and post-treatment magnetic resonance imaging analysis was completed for 23 patients using ImageJ software for an objective quantitative analysis of pixel density as a proxy for ACL integrity. Subjective clinical outcome measures collected pre-treatment and at 1, 3, 6, 12, 18, 24, and 36 months post-treatment include the Numerical Pain Scale (NPS), the Lower Extremity Functional Scale (LEFS), the International Knee Documentation...
Journal of experimental orthopaedics, Jan 25, 2017
Epidural steroid injections (ESI) are the most common pain management procedure performed in the ... more Epidural steroid injections (ESI) are the most common pain management procedure performed in the US, however evidence of efficacy is limited. In addition, there is early evidence that the high dose of corticosteroids used can have systemic side effects. We describe the results of a case series evaluating the use of platelet lysate (PL) epidural injections for the treatment of lumbar radicular pain as an alternative to corticosteroids. Registry data was obtained for patients (N = 470) treated with PL epidural injections presenting with symptoms of lumbar radicular pain and MRI findings that were consistent with symptoms. Collected outcomes included numeric pain score (NPS), functional rating index (FRI), and a modified single assessment numeric evaluation (SANE) rating. Patients treated with PL epidurals reported significantly lower (p < .0001) NPS and FRI change scores at all time points compared to baseline. Post-treatment FRI change score means exceeded the minimal clinically i...
Pain Research and Management, 2005
BACKGROUND: Minor impact soft tissue (MIST) is an insurance industry concept that seeks to identi... more BACKGROUND: Minor impact soft tissue (MIST) is an insurance industry concept that seeks to identify late whiplash as a psychosocial phenomenon. However, the medical literature in this area has not been systematically reviewed since the Quebec Task Force's review in 1995.OBJECTIVE: To review the medical literature which claims that late whiplash is an organic phenomenon causing significant disability.METHODS: The medical literature was reviewed in a narrative format.RESULTS: There are a significant number of studies which refute the MIST concept.CONCLUSIONS: A review of the literature did not support the validity of MIST.
Pain Research and Management, 2006
The authors undertook a case-control study of chronic neck pain and whiplash injuries in nine sta... more The authors undertook a case-control study of chronic neck pain and whiplash injuries in nine states in the United States to determine whether whiplash injuries contributed significantly to the population of individuals with chronic neck and other spine pain.Four hundred nineteen patients and 246 controls were randomly enrolled. Patients were defined as individuals with chronic neck pain, and controls as those with chronic back pain. The two groups were surveyed for cause of chronic pain as well as demographic information. The two groups were compared using an exposure-odds ratio. Forty-five per cent of the patients attributed their pain to a motor vehicle accident. An OR of 4.0 and 2.1 was calculated for men and women, respectively.Based on the results of the present study, it reasonable to infer that a significant proportion of individuals with chronic neck pain in the general population were originally injured in a motor vehicle accident.
Accuracy-the degree of closeness of quantitative measurements made with a measuring system to the... more Accuracy-the degree of closeness of quantitative measurements made with a measuring system to the quantity's true value. AIS-Abbreviated Injury Scale Association-The statistical relationship between events or variables. If the events occur more or less frequently together than one would expect by random chance then they are considered to be associated. Associations are not necessarily causal, however. ATD-Anthropomorphic Test Device; a crash test dummy Bayes' Theorem (alternatively Bayes' Law)-A method of revising or "conditioning" the probability of the occurrence of an event given the occurrence or non-occurrence of an associated event or events. Bias-In epidemiology bias refers to a form of error that may threaten the validity of a study by producing results that are systematically different than the true results. Two main categories of bias in epidemiologic studies are selection bias, which occurs when study subjects are selected as a result of another unmeasured variable that is associated with both the exposure and outcome of interest; and information bias, which is systematic error in the assessment of a variable. Biomechanics-The field of study pertaining to how force affects tissue. BMI-Body Mass Index, calculated by (weight in kg/(height in meters) 2) Case-control study-A retrospective study design that starts with the identification of persons with a particular disease or injury and compares them with a control group of persons without the same disease or injury for exposures of interest. The results are presented in the form of odds ratios. Causation-The relationship between an antecedent event, condition, characteristic, or agent that produces a disease or injury outcome. General causation is concerned with the cause of disease and injury in populations, and the proportion of the ill or injured population attributable to the exposure. Specific causation is concerned with the cause of disease and injury in individuals, and the probability that the condition would be present absent the exposure to the hazard. Specific causation is quantified by the assessment of the relative risk of cause, in which the hazard rate associated with the exposure of interest is compared with the base rate of the condition occurring at the same point in time absent the exposure. CNS-Central Nervous System, the brain and the spinal cord Cohort study-A study that starts with the identification of persons who have been exposed to a suspected cause of injury or disease, and compares them to an unexposed group of persons for 8 rate of occurrence of the disease or injury. The results are presented in the form of risk ratios.
Pain Research Management, 2005
Pain Research Management, 2005
NUMEROUS FACTORS ARE BELIEVED to influence the risk for injury to the cervical spine in low speed... more NUMEROUS FACTORS ARE BELIEVED to influence the risk for injury to the cervical spine in low speed automobile crashes. These include occupant stature, gender, position, age, pre-exiting health status, and awareness of impending crash. Factors extrinsic to the occupant that are thought to influence the risk for injury include seat back characteristics, head restraint geometry, type of restraint system used, crash speed, relative vehicle mass, and the direction of impact. Several studies have indicated that rear impact crashes are associated with greater risk for injury and, in some cases, a worse prognosis. Epidemiological studies have identified many risk factors, but the retrospective study design and wide ranging variables of real life crash scenarios has not allowed careful comparison of specific variables. We sought to answer the question concerning the possible reasons for the disparity in risk between front vector crashes and rear vector crashes using human subject crash testing.
Journal of rehabilitation medicine. Supplement, 2011
We are pleased to welcome you to the 5 th International Whiplash Trauma Congress (IWTC). This Con... more We are pleased to welcome you to the 5 th International Whiplash Trauma Congress (IWTC). This Congress will be a gathering place for presentation of the most advanced and enlightened concepts regarding whiplash trauma and injuries. The focus of the 5 th IWTC will be the multidisciplinary approach to understanding whiplash trauma; clinical, epidemiologic, engineering and biomechanical, as well as legal and forensic perspectives. There will be pre-and post congress courses and meetings, keynote lectures, poster-sessions and workshops.
Uploads
Papers by Michael Freeman