Abusive Head Trauma in Infants and Children: A Medical, Legal & Forensic Reference

By Lori Frasier, MD, FAAP, Kay Rauth-Farley, MD, FAAP, Randell Alexander, MD, PhD, FAAP and Robert Parrish, JD

630 pages, 611 images, 38 contributors


Abusive Head Trauma in Infants and Children combines the best clinical writing with high-quality photographic content found in color atlases -- a wealth of knowledge bound in one concise edition. This ebook features a four minute video explaining the mechanism of injury in shaken baby syndrome.


This reference addresses all aspects of abusive head trauma cases in one complete reference
for clinicians, investigators, prosecutors, and social workers. More than 600 clinical photographs illustrate inflicted child head injuries with case studies and multidisciplinary analyses, including discussions of shaken baby syndrome, shaken impact syndrome, differential diagnoses, forensic analysis, autopsies, prosecutorial issues, long-term care of survivors, and the role of social services.

• Language: English
• Publisher: GW Medical
• Release date: Jan 15, 2007
• ISBN: 9781878060082

Lori Frasier, MD, FAAP

Lori Frasier is the medical director of Medical Assessment at the Center for Safe and Healthy Families at Primary Children's Medical Center and associate professor of pediatrics at the University of Utah School of Medicine in Salt Lake City, Utah. Formerly, she was an assistant professor of Child Health and the director of the Child Protection Program and Division of General Pediatrics at the University of Missouri-Columbia. Dr. Frasier graduated from the University of Utah College of Medicine in 1995, completed her pediatric residency at the Children's Hospital and Medical Center/University of Washington in Seattle, Washington, and held a fellowship at the University of Washington's Sexual Assault Center. Dr. Frasier has authored several articles and chapters and lectured locally, regionally, and nationally on subjects related to child maltreatment.

Book preview

Chapter 1

CURRENT PERSPECTIVES ON ABUSIVE HEAD TRAUMA

Kay Rauth-Farley, MD

Lori D. Frasier, MD

Robert N. Parrish, JD

It is widely accepted that shaking a young child or infant is dangerous, yet education alone seems to be insufficient in preventing incidences of abusive head trauma (AHT). The main goal for professionals, caregivers, and parents alike is the elimination of child maltreatment. The rate for reports of maltreatment in 2000—12.2 per thousand—was the second lowest over the past decade; however, these are real children suffering physical and emotional pain. To prevent further occurrences of child maltreatment, caregivers must be given affirmative ways to handle the stresses of caring for children and provided incentives to consider those alternatives when faced with stressful situations.

AHT is a problem best addressed by a multidisciplinary team, including medical, investigative, legal, social service, and prevention professionals. This team approach has been formed over the course of the field’s history, from the first recognition of maltreatment in children through the development of its current level of knowledge and expertise.

HISTORY

Physical abuse by a caregiver has been recognized as a cause of traumatic injury in infants and children for nearly half a century. In 1961, the term battered child syndrome was coined by Dr. C. Henry Kempe as the title of the first multidisciplinary conference on the newly recognized problem of child abuse.¹ This conference is credited with eliciting a great outcry on behalf of abused children and garnering much-needed support for further study of the problem. In 1962, the results of this conference were published in the Journal of the American Medical Association (JAMA)² and in 1968 the first edition of the text The Battered Child was published with Drs. Ray Helfer and Henry Kempe as editors. This landmark text contained contributions from many of Helfer and Kempe’s colleagues, not only in pediatrics but also in radiology, mental health, law, and social services. The latest edition,¹ published in 1997, continues to present a multidisciplinary picture of the field of child maltreatment.

The term child maltreatment has replaced the original battered child syndrome term as a less offensive and all-encompassing way of describing the variety of injuries and illnesses in children caused by their caregivers. Thousands of children each year are seriously or permanently injured or killed by their caregivers. Many types of abusive injury have been described and studied since the 1960s, including skin surface injuries (ie, bruises, lacerations, and burns), bony trauma (ie, fractures), abdominal trauma, genital injuries, and head injuries, which are most frequently lethal.

Any type of abusive injury should be regarded as serious and worthy of attention and study; however, abusive head trauma is the primary cause of death from abuse in infants and young children.³,⁴ In 2000 a total of 1200 children in the United States died from abuse or neglect.⁵ Statistics on these deaths are collected through the National Child Abuse and Neglect Data System, but may underestimate the actual problem because of a lack of national definitions as well as nonuniform child fatality investigation and autopsy methods throughout the United States. Most of these child abuse fatalities in infants and children younger than 2 years result from AHT.

The entire multidisciplinary field of child maltreatment now exists due to the efforts of pioneering professionals, including thousands of professionals from the fields of law enforcement, medicine, law, social services, mental health, education, rehabilitation, prevention, and child advocacy. Over the last 4 decades, this field of study and service, which has been called by various names—child abuse, forensic pediatrics, and child maltreatment—has evolved into specialized subfields. This text focuses on that of abusive head injuries in infants and children, but injuries of many types are produced by maltreatment.

In 1946 pediatrician and radiologist Dr. John Caffey first questioned the association of bony injuries with head injuries in infants. He reported on 6 infants who suffered long-bone fractures and subdural hematomas.⁴ In none of his 6 cases was a history given to reasonably account for the presence of these injuries. One of the infants in Caffey’s 6 cases was noted to be clearly unwanted by both parents, causing the doctor to raise the question of possible intentional infliction of injury on the child. Caffey concluded in his report that the subdural hematomas and the long-bone fractures were caused by the same traumatic forces. He was the first to report such an association in medical literature. The presence of unrecognized traumatic injury in infants also caught the attention of Dr. Frederic Silverman, who in 1953 reported finding unsuspected fractures on routine presurgical radiographs in infants,⁶ reinforcing not only the prior radiographic findings of Caffey but also the lack of a credible history given by caregivers to account for the injuries.

Woolley and Evans⁷ authored a paper describing 9 years of injury data from the Children’s Hospital of Michigan. They found that many children had skeletal injuries associated with trauma, but no history of a traumatic event was obtained from caregivers. Some of these children also had associated subdural hematomas. An unknown syndrome was postulated to describe these nontraumatic findings. In summarizing the study the authors stated, It is difficult to avoid the overall conclusion that skeletal lesions having the appearance of fractures—regardless of history of injury or the presence or absence of intracranial bleeding—are due to undesirable vectors of force. Public acknowledgement of maltreatment in children as a problem⁸ nudged the medical profession into paying closer attention to the possibility of child abuse as a cause of traumatic injury, even in the absence of a clear history of trauma.

Twenty-six years after Caffey’s first report, following the important contributions of researchers such as Guthkelch⁹ and Ommaya,¹⁰-¹² Caffey’s often-cited article, On the Theory and Practice of Shaking Infants: Its Potential Residual Effects of Permanent Brain Damage and Mental Retardation¹³ appeared in the American Journal of Diseases in Children. Just 1 year previously, Guthkelch’s article on the relationship of subdural hematomas found in infants to the mechanism of whiplash injuries was published in the British Medical Journal.⁹ By that time Caffey was convinced that the cause of these head injuries in infants was manual shaking by their caregiver. He recognized that the history given by these caregivers was falsified and theorized that they did so out of fear of recrimination for causing the injuries. In addition, Caffey noted the frequent presence of retinal hemorrhages and the absence of external injuries in some cases. The outcomes for his group of patients included permanent brain damage, mental retardation, and death. In 1974 Caffey¹⁴ used the term whiplash shaken infant syndrome to describe this constellation of intracranial injuries, long-bone fractures, and frequently found retinal hemorrhages. The term shaken baby syndrome (SBS) came into general usage in the 1980s and remains a well-recognized means of describing this deadly constellation of findings.

As more and more infants with intracranial injuries, fractures of the ribs and long bones, and retinal hemorrhages were identified as being victims of a shaking incident, a recognizable pattern emerged. This pattern typically was found in young infants, usually younger than 1 year, who had sudden deterioration in mental status, possibly associated with an apneic episode or seizure. Frequently there were no external signs of injury to alert emergency medical personnel to the possibility of a traumatic etiology for the infant’s condition. The histories given by these children’s caregivers were often similar—denial of any traumatic event or the history of a seemingly trivial fall off of a bed or sofa or some other common household surface. So often was the history of a fall off of the sofa reported, that the term killer couch was coined sarcastically by those involved in the frequent investigation of such cases. These falls were reported frequently as being unwitnessed or witnessed only by caregivers present at the time children showed distress. On completion of a thorough medical evaluation, intracranial injuries were found, most commonly in the form of extraaxial bleeding—subdural or subarachnoid hemorrhages. Although usually no external injuries were noted, impact injuries were sometimes present in the form of skull fractures or scalp hematomas. In addition, retinal hemorrhages were often found, sometimes unilaterally, sometimes bilaterally. Radiological studies performed to look for bony injuries might reveal skull fractures. Very frequently, multiple rib fractures were identified, as well as metaphyseal fractures of the long bones.

MEDICAL ADVANCES AND CONTROVERSIES

Questions arose about the history of a fall frequently given by these infants’ care-givers. Could a short-distance fall inside a home cause such severe head injuries that infants were left brain damaged or dead? A review of literature on falls in children was an important adjunct to the developing strategy for identifying victims of SBS. A small but important body of information in the literature addressed injuries sustained in falls from beds and other common household surfaces.¹⁵-²² Some studies were done in semicontrolled settings such as hospitals. The preponderance of literature supported the belief that short-distance falls occurring inside the home were highly unlikely to cause a serious head injury resulting in permanent brain damage or death, though such serious injury could occur if the child suffered an epidural hemorrhage. Time was of the essence in caring for these children, and serious consequences could ensue were it not recognized and managed in a timely manner. Two studies specifically addressed injuries occurring from stairway falls,²³,²⁴ well supporting the fact that children who fall unintentionally down stairways suffer only minor injuries and do not exhibit permanent brain damage or death. Thus histories of minor falls given by caregivers of children with serious, life-threatening brain injuries are most likely falsified. These cases are to be reported to authorities as suspected abusive trauma or child abuse. In addition to alerting the authorities, a series of medical tests are performed looking for other unrecognized injuries and possible explanations for a child’s critical condition.

Despite efforts for nearly a decade to alert all medical personnel who treat SBS and its associated injuries, misleading histories proffered by the victims’ caregivers continue to lead to misdiagnosis.²⁵

Other important advances in the diagnosis of abusive trauma have taken place in the fields of ophthalmology and radiology. Current research has provided a better, though incomplete, understanding of the extent of retinal trauma in SBS.²⁶-³⁰ Now, not only must the presence of retinal hemorrhages in a suspected victim of SBS be reported, but a more precise description of the type, location, and extent of such findings is also necessary to help differentiate abusive retinal trauma from retinal findings resulting from other causes. Photographic documentation of retinal findings in cases of suspected SBS is becoming more common. This technique allows others besides the physician to actually view the evidence of retinal trauma.

Diagnostic imaging is a useful tool to detect the presence of previously unrecognized injury in cases of suspected abuse. The work of Kleinman,³¹-³⁴ including Diagnostic Imaging in Child Abuse,³⁵ provides a tremendous resource, and his work on the mechanism of posterior rib fractures in episodes of SBS compellingly supports this syndrome. The ability to explain to nonmedical professionals the mechanism by which ribs fracture under the force of adult hands around an infant’s torso has been a major benefit to educating investigators of SBS cases. In addition, the advances in imaging technology as applied to suspected child abuse cases allow for enhanced views of intracranial injury, aiding in the diagnosis and estimation of the timing of injury. New technologies such as magnetic resonance imaging (MRI) and improved computed tomography (CT) scans have resulted in better understanding of the timing and evolution of subdural and subarachnoid hemorrhages.³⁵,³⁶ Alexander et al³⁷ demonstrated that CT would not detect acute, high-convexity subdural hemorrhages that were well-demonstrated by MRI. More recently, proton magnetic resonance spectroscopy is being used to study the development of damage to neurons in instances of SBS.³⁸

One of the key controversies involving the SBS diagnosis was whether shaking alone was sufficient to cause the severe, life-ending injuries so many infants suffered. Although the early reports of intracranial injuries described by Caffey included children with obvious impact injuries, his emphasis was on the acceleration-deceleration injuries resulting from a whiplash or shaking event. The term shaken baby syndrome did not portray accurately the full picture seen in those infants who suffer not only acceleration-deceleration injuries but also impact injuries to the brain, skull, and soft tissues. Was it possible that all of these infants suffered some degree of impact that had a direct effect on the severity and type of injuries seen? Duhaime et al³⁹ strived to answer this question by developing complex biomechanical models equipped with accelerometers and subjecting them to acceleration-deceleration forces with and without impact. They looked at impact surfaces as well. Despite the limitations of these studies, they served an extremely important role in developing critical thinking about the mechanisms by which injuries occurred. The term shaken-impact syndrome came into use following this work. Over the next decade, more emphasis was placed on mechanisms of traumatic head injury as they related to clinical findings. The biomechanics of head injury in infants and young children is the current focus of much debate and study. A very useful but difficult approach was first presented to child abuse clinicians by Dr. Kent Hymel at the National Conference on Shaken Baby Syndrome and subsequently published in Child Maltreatment.⁴⁰ Because of the complex nature of traumatic brain injury, a more useful term has been used recently to encompass all possible mechanisms. The term abusive head trauma describes the circumstances surrounding head injuries but does not limit the scope of the mechanisms involved in producing the injuries seen. It is important to understand the mechanism of injury for each type of physical finding seen in infants and children who suffer abusive trauma; making a diagnosis of AHT is no longer a matter of simply identifying a constellation of injuries. The importance of understanding the mechanisms by which such findings develop is key to the diagnosis and treatment of the injuries, as well as to the education of professionals and the general public, the development of prevention programs, and the judicial proceedings designed to hold perpetrators of AHT accountable for their actions.

The concept that parents or caregivers have shaken infants so severely that permanent injury or death ensues is a difficult one for the lay public to accept. Caregivers of infants often do not fit a profile of a criminal, let alone one who may have murdered a child.⁴¹,⁴² As a consequence, numerous theories and controversies suggest alternative explanations. Some of those have proved to be helpful, such as the diagnosis of an inborn error of metabolism, glutaricaciduria type I (GAI), which has led clinicians to carefully consider such rare conditions as a cause of an infant’s sudden deterioration or demise.⁴³ Other theories have not proved helpful. Infant immunizations are now often implicated as a cause of the entire spectrum of conditions seen in abusive head trauma. This theory has followers but no credible scientific evidence to support it.⁴⁴ An excellent review of current controversies, such as the rebleeding theory to account for significant or fatal injury, the presence of a lucid interval, and the issue of cervical cord trauma in incidents of shaking, as well as medical diagnoses that may be confused with abuse, can be found in the work of Dr. Robert Block.⁴⁵ In this review, Block observes that these medical theories are being tested in courts of law rather than through peer-reviewed scientific study.

Although there is a tremendous amount of anecdotal, experiential, clinical, and analogous injury data supporting the concept that shaking or shaking with impact has such devastating consequences on the infant brain, the biomechanical analysis of forces necessary to cause such injury has recently come to the forefront. Some analyses suggest that sufficient forces cannot be generated through shaking to cause these injuries, but alternative analyses tend to disprove those theories (see Chapter 4, Biomechanics). Biomechanical and computerized models are currently under development. This analysis is extremely complex because of the physiological and mechanical properties of both the infant being subjected to abusive shaking and the perpetrator of the forces. Controversies within a field often serve to generate more rigorous assessment or reliance on our own clinical and epidemiological experience and are thus welcomed. However, sound, peer-reviewed scientific study must be the basis for new knowledge.

LEGAL AND INVESTIGATIVE ISSUES

Over the years, professionals from disciplines other than medicine have been called upon to identify victims and prevent children from suffering injury at the hands of their caregivers. Across the world, medical professionals work closely with law enforcement and social service investigators to identify, treat, and protect victims of AHT from further injury. Investigators, attorneys, and judges struggle to hold accountable those who inflict this form of abuse on young children.

Abusive head trauma cases involving young victims can be among the most difficult to deal with in the legal system, primarily because there are few cases in which there are any eyewitnesses and many cases lack external injuries that clearly identify the mechanism that resulted in harm. Criminal investigators and prosecutors are almost always confronted with the daunting task of proving a case beyond any reasonable doubt through the use of completely circumstantial evidence. Few other crimes present the added difficulty of proving that defendants who appear to be normal people, often without a history of violence, are capable of causing serious head injuries or death to infants or young children in their care.

It sometimes occurs that detectives or prosecutors are assigned their first case of AHT after many years of prior experience. Traditional investigative and courtroom techniques may not be effective in proving these highly specialized, medical expert intensive cases.

Investigators must learn enough about the medical aspects of these cases to recognize when they are being told falsified stories by caregivers attempting exoneration for inflicting serious injuries on children. Investigators must also learn new techniques for confronting suspected perpetrators to obtain an admission. Prosecutors must learn that when caregivers offer fabricated stories to account for abusive injuries to children, caregivers are providing the evidence of mental state, awareness of the need to cover up the crime, and identity of the perpetrator of the abuse. Prosecutors must become familiar with new techniques for simplifying the presentation of medical expert evidence and of cross-examining medical witnesses called by the defendant.

The most important lesson for all criminal justice professionals is that there is no profile of common perpetrators in AHT cases. Although many injuries are caused by persons who have a history of violence, anger control problems, or even child abuse, a very high number of cases involve perpetrators who have no such history (see Chapter 28, Prevention and Education). No demographic variable is common to all cases. Even people who are described as the perfect parent or the most loving babysitter are capable of causing serious head trauma to children if caused to lose their temper. Both investigators and prosecutors must set aside any preconceived notions they might have as to who is capable of this crime in order to make accurate charging decisions. Prosecutors must be prepared to educate juries and judges about the lack of any profile and to try to penetrate the jurors’ or judges’ assumptions that anyone who would cause serious head injury to children must appear as a monster. Many cases result in an acquittal even when the medical evidence overwhelmingly points to the guilt of defendants, simply because defendants do not fit the preconceived image expected by jurors or judges.

Social service workers, child protection attorneys in juvenile court, and all other attorneys tasked with proving cases of inflicted head trauma on young victims must also obtain basic education on AHT. Those whose job involves protecting children from further abuse must understand the medical issues surrounding AHT in order to identify risk factors that apply to all children in the care of suspected perpetrators. Child protective service (CPS) workers must understand the risk presented by those who commit AHT against young children to other children or to the same victims if they do not admit what they did and seek behavioral change.

INTERDISCIPLINARY APPROACH

Professionals from medicine, law enforcement, social service, the legal field, child advocacy, education, prevention, and even the media will find it important to have an understanding of AHT. Rehabilitation specialists work to identify the long-term needs of those who survive abuse and strive to provide for their physical and educational needs.⁴⁶-⁴⁸ Children’s advocacy groups work to develop programs aimed at education and prevention.⁴⁹-⁵¹ In each of these professionally diverse fields, progress has been made recently. New technology has allowed for quicker and more accurate medical diagnosis and treatment, as well as improved methods of educating juries, judges, and the general public on this issue. Communities across the world have developed multidisciplinary teams of professionals involved in the child abuse crisis to address locally how they might improve the identification, investigation, and prosecution of these cases. The media has brought the problem of AHT into the homes of the general public by broadcasting reports of such incidents and the legal proceedings that ensue.

CONCLUSION

Although much progress has been made, there is always more to learn and newer, better ways to accomplish goals. The challenge for all professionals is to find ways to share information with each other, to form interdisciplinary teams to effectively respond when cases are presented, and to encourage continuing research to answer the questions that remain concerning AHT in children. Professionals in all disciplines must understand their role and how it interfaces with that of all other professionals. Everyone who comes in contact with AHT cases must realize the tremendous tragedy involved when caregivers maim or kill young children through a momentary loss of control. The victims in such cases include not just children, but family members, often including perpetrators of the violence. Perpetrators rarely set out with a purpose to kill or permanently injure young children, yet when their actions cause that result, they destroy their own lives as well as those of their child victims.

With that in mind, the ultimate goal of everyone touched by these tragic cases is prevention of future tragedies.

REFERENCES

1.Helfer ME, Kempe RS, Krugman RD. The Battered Child. Chicago, Ill: University of Chicago Press; 1997.

2.Kempe CH, Silverman FN, Steele BF, Droegemueller W, Silver HK. The battered-child syndrome. JAMA. 1962;181:17-24.

3.American Academy of Pediatrics, Committee on Child Abuse and Neglect. Shaken baby syndrome: rotational cranial injuries—technical report. Pediatrics. 2001;108:206-210.

4.Case ME, Graham MA, Handy TC, Jentzen JM, Monteleone JA, and the National Association of Medical Examiners Ad Hoc Committee on Shaken Baby Syndrome. Position paper on fatal abusive head injuries in infants and young children. Am J Forensic Med Pathol. 2001;22:112-122.

5.Walter R. McDonald & Associates, Inc. Child Maltreatment 2000. Washington, DC: Children’s Bureau, Administration on Children, Youth and Families, US Dept of Health and Human Services; 2002. Available at: http://www.acf.hhs.gov/programs/cb/publications/cm00/cm2000.pdf. Accessed April 13, 2005.

6.Silverman FN. Roentgen manifestations of unrecognized skeletal trauma in infants. Am J Roentgenol Radium Ther Nucl Med. 1953:69:413-427.

7.Woolley PV Jr, Evans WA Jr. Significance of skeletal lesions in infants resembling those of traumatic origin. JAMA. 1955;158:539-543.

8.Caffey J. Multiple fractures in the long bones of infants suffering from chronic subdural hematoma. AJR Am J Roentgenol. 1946;56:163-173.

9.Guthkelch AN. Infantile subdural haematoma and its relationship to whiplash injuries. Br Med J. 1971;2:430-431.

10.Ommaya AK, Faas F, Yarnell P. Whiplash injury and brain damage: an experimental study. JAMA. 1968;204:285-289.

11.Ommaya AK, Grubb RL Jr, Naumann RA. Coup and contre-coup injury: observations on the mechanics of visible brain injuries in the rhesus monkey. J Neurosurg. 1971;35:503-516.

12.Ommaya AK, Hirsch AE. Tolerances for cerebral concussion from head impact and whiplash in primates. J Biomech. 1971;4:13-21.

13.Caffey J. On the theory and practice of shaking infants. Its potential residual effects of permanent brain damage and mental retardation. Am J Dis Child. 1972; 124:161-169.

14.Caffey J. The whiplash shaken infant syndrome: manual shaking by the extremities with whiplash-induced intracranial and intraocular bleedings, linked with residual permanent brain damage and mental retardation. Pediatrics. 1974;54: 396-403.

15.Chadwick DL, Chin S, Salerno C, Landsverk J, Kitchen L. Deaths from falls in children: how far is fatal? J Trauma. 1991;31:1353-1355.

16.Helfer RE, Slovis TL, Black M. Injuries resulting when small children fall out of bed. Pediatrics. 1977;60:533-535.

17.Kravitz H, Driessen G, Gomberg R, Korach A. Accidental falls from elevated surfaces in infants from birth to one year of age. Pediatrics. 1969;44(suppl): 869-876.

18.Lyons TJ, Oates RK. Falling out of bed: a relatively benign occurrence. Pediatrics. 1993;92:125-127.

19.Nimityongskul P, Anderson LD. The likelihood of injuries when children fall out of bed. J Pediatr Orthop. 1987;7:184-186.

20.Selbst SM, Baker MD, Shames M. Bunk bed injuries. Am J Dis Child. 1990;144: 721-723.

21.Tarantino CA, Dowd MD, Murdock TC. Short vertical falls in infants. Pediatr Emerg Care. 1999;15:5-8.

22.Williams RA. Injuries in infants and small children resulting from witnessed and corroborated free falls. J Trauma. 1991;31:1350-1352.

23.Chiaviello CT, Christoph RA, Bond GR. Stairway-related injuries in children. Pediatrics. 1994;94:679-681.

24.Joffe M, Ludwig S. Stairway injuries in children. Pediatrics. 1988;82(pt 2): 457-461.

25.Jenny C, Hymel KP, Ritzen A, Reinert SE, Hay TC. Analysis of missed cases of abusive head trauma. JAMA. 1999;281:621-626.

26.Buys YM, Levin AV, Enzenauer RW, et al. Retinal findings after head trauma in infants and young children. Ophthalmology. 1992;99:1718-1723.

27.Levin AV. Ocular manifestations of child abuse. Ophthalmol Clin North Am. 1990;3:249-264.

28.Levin AV. Retinal hemorrhages: a review. In: David TJ, ed. Recent Advances in Pediatrics. London, England: Churchill Livingstone; 1999.

29.Odom A, Christ E, Kerr N, et al. Prevalence of retinal hemorrhages in pediatric patients after in-hospital cardiopulmonary resuscitation: a prospective study. Pediatrics. 1997;99:e3.

30.The Ophthalmology Child Abuse Working Party. Child abuse and the eye. Eye. 1999;13(pt 1):3-10.

31.Kleinman PK, Marks SC Jr, Nimkin K, Rayder SM, Kessler SC. Rib fractures in 31 abused infants: postmortem radiologic-histopathologic study. Radiology. 1996;200:807-810.

32.Kleinman PK, Marks SC Jr. A regional approach to the classic metaphyseal lesion in abused infants: the proximal humerus. AJR Am J Roentgenol. 1996;167:1399-1403.

33.Kleinman PK, Nimkin K, Spevak MR, et al. Follow-up skeletal surveys in suspected child abuse. AJR Am J Roentgenol. 1996;167:893-896.

34.Kleinman PK, Schlesinger AE. Mechanical factors associated with posterior rib fractures: laboratory and case studies. Pediatr Radiol. 1997;27:87-91.

35.Kleinman PK. Diagnostic Imaging of Child Abuse. 2nd ed. St Louis, Mo: Mosby; 1998.

36.Feldman KW, Brewer DK, Shaw DW. Evolution of the cranial computed tomography scan in child abuse. Child Abuse Negl. 1995;19:307-314.

37.Alexander RC, Schor D, Smith WL Jr. Magnetic resonance imaging of intracranial injuries from child abuse. J Pediatr. 1986;109:975-979.

38.Haseler LJ, Arcinue E, Danielsen ER, Bluml S, Ross BD. Evidence from proton magnetic resonance spectroscopy for a metabolic cascade of neuronal damage in shaken baby syndrome. Pediatrics. 1997;99:4-14.

39.Duhaime AC, Gennarelli TA, Thibault LE, Bruce DA, Margulies SS, Wiser R. The shaken baby syndrome. A clinical, pathological and biomechanical study. J Neurosurg. 1987;66:409-415.

40.Hymel KP, Bandak FA, Partington MD, Winston KR. Abusive head trauma? A biomechanics-based approach. Child Maltreat. 1998;3:116-128.

41.Brewster AL, Nelson JP, Hymel KP, et al. Victim, perpetrator, family and incident characteristics of 32 infant maltreatment deaths in the United States Air Force. Child Abuse Negl. 1998;22:91-101.

42.Starling SP, Holden JR, Jenny C. Abusive head trauma: the relationship of perpetrators to their victims. Pediatrics. 1995;95:259-262.

43.Baric I, Zschocke J, Christensen E, et al. Diagnosis and management of glutaric aciduria type I. J Inherit Metab Dis. 1998;21:326-340.

44.Chadwick DL, Parrish R. DTP Vaccination or shaken baby syndrome? The role of irresponsible medical expert testimony in creating a false causal connection. Update. 2000;13(9). Available from: The National Center for Prosecution of Child Abuse, at http://www.ndaa-apri.org/publications/newsletters/update_volume_13_number_9_2000.html. Accessed April 12, 2005.

45.Block RW. Child abuse—controversies and imposters. Curr Probl Pediatr. 1999; 29: 249-272.

46.Andrews TK, Rose FD, Johnson DA. Social and behavioural effects of traumatic brain injury in children. Brain Inj. 1998;12:133-138.

47.Ewing-Cobbs L, Kramer L, Prasad M, et al. Neuroimaging, physical, and developmental findings after inflicted and noninflicted traumatic brain injury in young children. Pediatrics. 1998;102(pt 1):300-307.

48.Fischer H, Allasio D. Permanently damaged: long-term follow-up of shaken babies. Clin Pediatr (Phila). 1994;33:696-698.

49.Dias MS. Reducing the incidence of abusive head trauma through hospital-based parent education: The Upstate New York Shaken Baby Syndrome Education Program. Paper presented at: European Conference on Shaken Baby Syndrome; May 19, 2003; Edinburgh, Scotland.

50.Showers J. Don’t shake the baby: the effectiveness of a prevention program. Child Abuse Negl. 1992;16:11-18.

51.Showers J, Johnson CF. Child development, child health and child rearing knowledge among urban adolescents: are they adequately prepared for the challenges of parenthood? Health Educ. 1985;16:37-41.

Chapter 2

EPIDEMIOLOGY OF TRAUMATIC BRAIN INJURY: RECOGNIZING UNINTENTIONAL HEAD INJURIES IN CHILDREN

M. Denise Dowd, MD, MPH

MAGNITUDE OF THE PROBLEM

Each year in the United States approximately 100 of every 100 000 children younger than 6 years suffer from traumatic brain injuries resulting in death or hospitalization.¹ Eighty-two percent of all head injuries are considered mild (Glasgow Coma Scale [GCS] >12), 14% are moderate (GCS 8-12) to severe (GCS <8), and 5% are fatal. Children have the highest rate of minor head injuries compared to other age-groups. Each year 400 000 children younger than 5 years are treated for minor head injuries in emergency departments and outpatient clinics.² Outcomes of unintentional head injury vary from complete recovery to severe impairment and depend on the severity of initial injury mechanisms and secondary brain injuries, or brain damage that results from swelling after the injury. An estimated 30 000 or more children sustain permanent disabilities as a result of brain injury every year.³ Although head injuries remain at levels demanding greater prevention measures, recent data indicate that head injury hospitalization and deaths among children have declined significantly in the United States since the early 1980s.⁴ This is a tribute to the success of injury prevention measures such as child safety seats and bicycle helmets. The decrease is also partially explained by a tendency toward less hospitalization in recent years.

For children aged 5 years and younger, the leading mechanisms and annual rates of head injuries are falls (50.6 per 100 000 children), motor vehicle crashes (25.9 per 100 000 children), and abuse (12.8 per 100 000 children).¹ Mechanisms of head injury vary with developmental vulnerabilities that change rapidly during the first 5 years of life. For infants younger than 1 year, serious head injuries are most commonly caused by abuse, whereas the majority of head-injured children older than 1 year are injured by unintentional means. Severe accidental head injuries in infants are rare, as indicated by a study that found, excluding uncomplicated skull fractures, 95% of serious intracranial injuries and 64% of all head injuries in infants are the result of abuse.⁵

As with the majority of childhood traumas, accidental head injuries are more common in males and occur when children are most active—the spring and summer months and weekends. Certain medical disorders, including hydrocepahalus with a shunt and coagulation disorders such as hemophilia and vitamin K deficiency, increase the risk for intracranial injuries with a smaller degree of force.

COMMON MECHANISMS OF HEAD INJURY

Mechanisms predict the resulting types of head injuries. General categories of head injury mechanisms include direct contact to the head, acceleration or deceleration of the brain within the skull, and hypoxia-ischemia. Events leading to injury may involve a combination of these mechanisms. Most severe unintentional head injuries are accompanied by dramatic and notable histories of injury. Many abusive head injury patients are brought to medical attention with histories of accidental injury; thus, it is important to understand the typical ways in which childhood unintentional head injuries occur and the types of physical findings to expect. Several of the more common causes of unintentional head injury are specifically described.

FALLS

Falls Down Stairs

Though parents often are frightened when skull fractures occur, falls down stairs, excluding those in walkers, rarely lead to serious intracranial injuries. Falls down stairs include an initial fall followed by a series of several small falls, with physical damage occurring as the result of the cumulative effect of kinetic energy generated in several impacts. A study of 363 cases of stair falls by Joffe and Ludwig⁶ found that 28% of the children sustained skull fractures and no patient suffered intracranial injuries. Skull fracture occurrence increased to 40% when children fell while in the arms of caregivers. Chiaviello et al⁷ found that 3 of 69 children who fell down stairs sustained intracranial injuries, 1 with a subdural hematoma and 2 with cerebral contusions. Two of these more seriously injured patients were being carried in their caregivers’ arms. No correlation between severity of injury and number of stairs involved in the fall was noted in either study.

Falls in Walkers

When children fall down stairs in infant walkers, the potential for serious injury increases significantly. The Consumer Product Safety Commission estimates that 25 000 children are treated for infant walker–related injuries in emergency departments in the United States each year and that about 80% of them involve falls down stairs. The vast majority (95%) are younger than 15 months, and one fourth of them sustain injuries classified as more severe, which includes head injuries and fractures. One child per year dies in the United States because of a walker-related head injury.⁸ Two studies found that 10% to 15% of children sustained skull fractures and 1% to 8% had intracranial bleeding, including subdural hematomas.⁹,¹⁰ Risks for skull fracture varied depending upon the number of steps fallen down and whether infants struck a concrete floor.¹⁰ Pediatric injury prevention experts and medical organizations such as the American Academy of Pediatrics recommend that infant walker manufacturing and sales be banned¹¹; nonetheless, use of walkers is still relatively common. Alternative nonmobile infant seating options such as exersaucers have become increasingly popular, but safety comparison information on these items is not available.

Falls From Shopping Carts

Falls from shopping carts are an important cause of pediatric head trauma to consider. In 1996, 16 000 children were treated for falls from shopping carts, 66% of whom sustained head injuries such as concussions or skull fractures.¹² Fortunately, severe intracranial injuries in these falls are rare. Smith et al¹³ found that about 26% of cart-related falls occur when shopping carts tip over. About half of children falling from carts fall from the seat and the other half fall from the basket.¹³

Short Vertical Falls

Short vertical falls from heights lower than 4 feet (eg, out of bed, from a highchair, out of the arms of a caregiver) are common. These falls included those from inappropriately placed car seats and bouncy chairs. Caregivers underestimate the mobility of infants and may place such seats on elevated surfaces, such as counters or tables, from which they fall.¹⁴,¹⁵ Most children do not visit physicians after such falls because injuries are frequently negligible. Several investigators have studied short vertical falls and demonstrated that these falls do not typically result in serious intracranial injuries,¹⁶-²⁰ though simple linear skull fractures have been known to occur. Depressed skull fractures are uncommon and have been noted only in short, witnessed falls in which children fell against a hard edge.²¹ Though epidural hematomas are rare, they are possible after short vertical falls, particularly if there is a direct blow to the parietal skull overlying the middle meningeal artery. Subdural hematomas do not result from short vertical falls but have been noted in household falls from heights exceeding 4 feet (eg, top bunk of a bunk bed).²² Duhaime et al,¹⁶ in a series of 100 children younger than 2 years, found links between mechanisms of injury and injury types in children with accidental trauma. In this study, simple linear skull fractures were as likely to occur from falls of less than 4 feet as from falls of greater than 4 feet, down stairs, or in walkers. However, complex skull fractures, such as depressed and basilar or bilateral skull fractures, were more likely to occur from greater heights and falls down stairs. All noninflicted epidural hematomas in this study occurred as a result of falls from less than 4 feet, but no other types of intracranial injuries were attributed to short falls.¹⁶

It is still difficult to determine the minimum height at which severe head injuries can potentially occur. Many factors determine the potential for injury, including the distance fallen, the resistance of the surface fallen onto, rotational forces, whether the fall is broken in some manner, if the child hits another object on the way down, or whether the child was in motion or was propelled before hitting the surface. The age of children is important because younger skulls are more elastic and resistant to skull fractures. False histories of short vertical falls are given in a significant proportion of abusive head trauma cases.

MOTOR VEHICLE CRASHES

Motor vehicle crashes are responsible for most severe unintentional childhood head injuries. Specific intracranial findings are related to the acceleration-deceleration mechanism typical in car crashes or direct contact of the head with fixed objects in the automobile. Similar injuries are found in the abusive head injury mechanism of shaking or shaking-impact and include subdural and epidural hematomas, brain contusions, and diffuse axonal injuries. Secondary injuries may occur as the result of shock caused by hemorrhages from concomitant severe thoracic and abdominal injuries. Ejection from the car is often fatal and greatly increases the potential for severe brain injury. Proper use of child safety seats results in neck and head support, prevents ejection from the automobile, and significantly decreases the potential for severe head injury in the event of a motor vehicle crash.

PLAYGROUND INJURIES

An estimated 150 000 visits to US emergency departments each year are for injuries occurring on playgrounds. After extremity injuries, head injuries are the second most common type of injury sustained on playgrounds.²³ Fortunately, the vast majority of the injuries consist of minor head trauma. Playground head injuries are typically caused by falls, and the severity of injury depends on the height from which the child falls and the surface fallen upon. Surfaces with greater shock-absorbing ability, including rubberized surfaces or those with at least 12 inches of loose fill (eg, pea gravel, wood chips), are less likely to be associated with severe head injuries. Compact, firm surfaces such as concrete, asphalt, grass, and dirt put children at greater risk of head injury and are not recommended for use in playgrounds.

INTRACRANIAL INJURIES

Intracranial injuries are significantly more common in cases of abused children than in those with unintentional mechanisms.²⁴ Major differences in the frequencies of specific types of intracranial injuries have been documented. A recent study observed subdural hematomas in 10% of children with unintentional trauma and 46% of those with abusive head trauma. Similarly, subarachnoid hemorrhages occurred more frequently in abused cases than in those with accidental trauma (31% vs. 8%, respectively).²⁵ Shugerman et al²⁶ found that epidural hematomas are more common in children with unintentional head injuries than those with abusive head trauma. This study documented cases of children with epidural or subdural hematomas treated at single institutions and determined that 47% of patients with subdural hematomas, compared to 6% of those with epidural hematomas, were abused.²⁶

DIFFERENTIATING ABUSIVE FROM UNINTENTIONAL HEAD INJURY

Differentiating abusive from unintentional head injuries can be difficult and troublesome for physicians. To determine how frequently abusive head trauma was missed by physicians, Jenny et al²⁷ and others performed a 6-year study and found that in one third of child head trauma cases the diagnosis was not recognized on initial examination and the mean time to arrive at a correct diagnosis was 7 days. In this study the most common erroneous diagnoses included viral syndromes, unintentional head injuries, and rule out sepsis. Compared with recognized abusive head trauma, cases from traditional families were significantly more likely to be mis-diagnosed.

Unintentional and abusive mechanisms can result in various intracranial injuries. Injuries must be understood in context of the entire historical and clinical picture, not in isolation, in order to determine whether a given intracranial finding is the result of abuse. Carefully collected and documented histories and meticulous physical examinations are essential to determine cases of head trauma to be accidental or abusive. A basic understanding of the mechanisms that result in severe head injury is important because children with abusive head trauma frequently are reported for examination and treatment with falsified histories of unintentional trauma.²⁸

In conjunction with histories, physical examinations of children must be undertaken with considerable care, regardless of the intent or mechanism. The findings of the examination must match the history of the injury. A depressed neurological state can make discovery of concomitant injuries difficult. Abusive head trauma is frequently accompanied by other injuries of a serious or minor nature. One of the most well documented concepts in abusive head injury identification has been the relationship between abusive head trauma and other injuries, such as long-bone fractures.²⁹ Early definitions of battered child syndrome included head injury,³⁰ and subsequent literature has supported that finding. Severe head injuries with inconsistent histories warrant skeletal surveys for occult fractures. Table 2-1 presents the most common indicators differentiating abusive from unintentional head injuries.

RETINAL HEMORRHAGES

A thorough understanding of the occurrence of retinal hemorrhages in children who sustain unintentional head injuries is important in determining accidental or abusive mechanisms of injury. Though retinal hemorrhages in children who have unintentional head injuries have been documented,¹⁶ they are in the context of severe multiple traumas involving high-energy acceleration-deceleration mechanisms such as falls from great heights or motor vehicle crashes. Children with such injuries are brought for medical examination with a history of dramatic mechanisms of injury and, most frequently, multiple traumas. Birth trauma causes retinal hemorrhage in 34% of all newborns, but these hemorrhages reabsorb by the age of 2 weeks in 86% of cases and by the age of 4 weeks in all children.³¹ Another, more unusual cause of retinal hemorrhage is exposure to high altitude. This painless condition occurs in half of all individuals who climb to levels above 16 500 feet and in 100% of those who ascend to 21 000 feet. It may be a warning sign of impending cerebral edema.³²

PREVENTION

The majority of accidental head injuries are preventable with the appropriate use of child safety seats and bicycle helmets, adequate observation of children, and other strategies involving what are commonly know as the 4 E’s:

—Enforcement of laws

—Education in safety measures

—Environmental modification

—Economic incentives

The greatest impact can be made when a strategy combines all 4 approaches. Table 2-2 provides a list of examples of each type of intervention.

Table2-2

Enforcement of strong laws, including motorcycle helmet and bicycle helmet laws, speeding restrictions, drunk driving laws, and laws pertaining to seat belts and child safety seats, has been particularly effective in reducing accidental head injuries.

Modification of the child’s environment has also been very effective in reducing the risk of accidental head injuries. Examples include childproofing homes by putting gates in front of stairs and window guards to prevent falls. Effective modifications in public spaces include the use of safety surfacing on playgrounds, use of traffic-slowing devices such as speed bumps and traffic circles, and physically separating bicycle riders from traffic with bicycle paths.

Education is effective when done in a focused, concerted method and aimed at specific groups. Reinforcement of educational messages over time and by several groups of individuals is an important determinant of success. The Seattle bicycle helmet community education program is an excellent example of such a program.³³

Economic incentives may be directed at individuals through private business efforts such as a reduction in insurance rates for the wearing of seat belts or through state or local governmental programs. State governments may enact and enforce driving laws with lower acceptable levels of driver blood alcohol when federal highway dollars are at stake. Federal incentive grants have been provided to states that have enacted and are enforcing laws lowering acceptable driver blood alcohol levels to a maximum of 0.08% or less. Such grants may be used for highway safety and highway construction programs.

RESOURCES FOR CHILDHOOD HEAD INJURY PREVENTION

The following resources are helpful to caregivers and child care professionals in the prevention of accidental head injuries in children:

—National Bicycle Safety Network. The NBSN Website, http://www.cdc.gov/ncipc/bike/, has information about preventing head injuries through bicycle helmet use.

—National Program for Playground Safety. The NPPS Website, http://www.uni.edu/playground, has safety measures that can reduce the risk of falls on the playground that may result in head injury. The program may also be contacted at 1-800-554-PLAY (7529).

—National Highway Traffic Safety Administration. The NHTSA Website, http://www.nhtsa.dot.gov/people/injury/childps/, has useful information on child passenger seat guidelines and specifics on buying car seats and safe cars. The NHTSA also provides an auto safety hotline: [phone].

—Think First Foundation. Think First, at http://www.thinkfirst.org, provides public education programs that seek to educate children and young people about personal vulnerability and risk-taking. Topics covered in educational programs include an introduction to the brain and spinal cord anatomy; vehicle, water, bicycle, sports, and recreational safety; safety around weapons; and creative problem solving.

CONCLUSION

No single test can differentiate abusive from unintentional head injury. In view of the lack of determinants of abusive injury, the history provided by caregivers must correspond to the findings on physical examination. Clinicians must take a detailed history, including mechanism of injury, whether it was witnessed, who provided the history, and if it is consistent over time. In cases of unintentional head injury the history is most often clear and consistent with the type of injury and there are no additional unexplained injuries.

REFERENCES

1.Centers for Disease Control and Prevention. Traumatic brain injury—Colorado, Missouri, Oklahoma, and Utah, 1990-1993. MMWR Morb Mortal Wkly Rep. 1997;46:8-11.

2.Guerrero JL, Thurman DJ, Sniezek JE. Emergency department visits associated with traumatic brain injury: United States, 1995-1996. Brain Inj. 2000;14:181-186.

3.National Pediatric Trauma Registry, Research and Training Center in Rehabilitation and Childhood Trauma. National Pediatric Trauma Registry. Boston, Mass: Tufts University School of Medicine, New England Medical Center; Spring, 1993.

4.Thurman D, Guerrero J. Trends in hospitalization associated with traumatic brain injury. JAMA. 1999;282:954-957.

5.Billmire ME, Myers PA. Serious head injury in infants: accident or abuse? Pediatrics. 1985;75:340-342.

6.Joffe M, Ludwig S. Stairway injuries in children. Pediatrics. 1988;82(pt 2): 457-461.

7.Chiaviello CT, Christoph RA, Bond GR. Stairway-related injuries in children. Pediatrics. 1994;94:679-681.

8.Consumer Product Safety Commission. Baby walkers: advance notice of proposed rulemaking. Federal Register. 1994;59:39306-39311.

9.Chiaviello CT, Christoph RA, Bond GR. Infant walker-related injuries: a prospective study of severity and incidence. Pediatrics. 1994;93(pt 1):974-976.

10.Smith GA, Bowman MJ, Luria JW, Shields BJ. Babywalker-related injuries continue despite warning labels and public education. Pediatrics. 1997;100:e1.

11.American Academy of Pediatrics. Committee on Injury and Poison Prevention. Injuries associated with infant walkers. Pediatrics. 1995;95:778-780.

12.Consumer Product Safety Commission (CPCS). Shopping cart injuries: victims 5 years old and younger. Available at: http://www.cpsc.gov/library/shopcart.html. Accessed May 12, 2005.

13.Smith GA, Dietrick AM, Garcia CT, Shields BJ. Injuries to children related to shopping carts. Pediatrics. 1996;97:161-165.

14.Pollack-Nelson C. Falls and suffocation injuries associated with in-home use of car seats and baby carriers. Pediatr Emerg Care. 2000;16:77-79.

15.Wickham T, Abrahamson E. Head injuries in infants: the risks of bouncy chairs and car seats. Arch Dis Child. 2002;86:168-169.

16.Duhaime AC, Alario AJ, Lewander WJ, et al. Head injury in very young children: mechanisms, injury types, and ophthalmologic findings in 100 hospitalized patients younger than 2 years of age. Pediatrics. 1992;90(pt 1):179-185.

17.Helfer RE, Slovis TL, Black M. Injuries resulting when small children fall out of bed. Pediatrics. 1977;60:533-535.

18.Lyons TJ, Oates RK. Falling out of bed: a relatively benign occurrence. Pediatrics. 1993;92:125-127.

19.Nimityongskul P, Anderson LD. The likelihood of injuries when children fall out of bed. J Pediatr Orthop. 1987;7:184-186.

20.Tarantino CA, Dowd MD, Murdock TC. Short vertical falls in infants. Pediatr Emerg Care. 1999;15:5-8.

21.Williams RA. Injuries in infants and small children resulting from witnessed and corroborated free falls. J Trauma. 1991;31:1350-1352.

22.Selbst SM, Baker MD, Shames M. Bunk bed injuries. Am J Dis Child. 1990;144: 721-723.

23.Phelan KJ, Khoury J, Kalkwarf HJ, Lanphear BP. Trends and patterns of playground injuries in United States children and adolescents. Ambul Pediatr. 2001; 1:227-233.

24.DiScala C, Sege R, Li G, Reece RM. Child abuse and unintentional injuries: a 10-year retrospective. Arch Pediatr Adolesc Med. 2000;154:16-22.

25.Reece RM, Sege R. Childhood head injuries: accidental or inflicted? Arch Pediatr Adolesc Med. 2000;154:11-15.

26.Shugerman RP, Paez A, Grossman DC, Feldman KW, Grady MS. Epidural hemorrhage: is it abuse? Pediatrics. 1996;97:664-668.

27.Jenny C, Hymel KP, Ritzen A, Reinert SE, Hay TC. Analysis of missed cases of abusive head trauma. JAMA. 1999;281:621-626.

28.O’Neill JA Jr, Meacham WF, Griffin JP, Sawyers JL. Patterns of injury in the battered child syndrome. J Trauma. 1973;13:332-339.

29.Caffey J. Multiple fractures in long bones of infants suffering from chronic subdural hematoma. AJR Am J Roentgenol. 1946;56:163-173.

30.Kempe CH, Silverman FN, Steele BF, Droegemueller W, Silver HK. The battered-child syndrome. JAMA. 1962;181:17-24.

31.Emerson MV, Pieramici DJ, Stoessel KM, Berreen JP, Gariano RF. Incidence and rate of disappearance of retinal hemorrhage in newborns. Ophthalmology. 2001;108:36-39.

32.McFadden DM, Houston CS, Sutton JR, Powles AC, Gray GW, Roberts RS. High-altitude retinopathy. JAMA. 1981;245:581-586.

33.Rivara FP, Thompson DC, Thompson RS, et al. The Seattle children’s bicycle helmet campaign: changes in helmet use and head injury admissions. Pediatrics. 1994;93:567-569.

Chapter 3

UNINTENTIONAL HEAD INJURIES: CASE STUDIES

Todd C. Grey, MD

The patterns of injury seen in accidental lethal head trauma are striking. The typical findings in a case of immediately or rapidly fatal accidental head injury in which the child is pronounced dead at the scene or within a short time of arriving at the hospital have an array of cutaneous, skeletal, and intracranial findings. While the extent of injury in the various structural layers of the head may at times be discrepant, there is always something in the pattern and extent of injury that is indicative of a significant amount of force being delivered to the head. What is even more striking is the clear correlation between the severity of injury and the mechanism of injury provided in the history. The injuries present in the patient are reasonable given the explanation provided for these injuries, which is in sharp contrast to the often trivial mechanisms offered as an explanation for a child’s injuries in cases of abusive trauma. The cases in this chapter are graphic in their presentation but serve to emphasize the dramatic and distinct nature of the injuries. It is also notable that tremendous forces are involved when accidental fatal head trauma occurs in the case of motor vehicle collisions, a horse falling on a child, or an adult falling down stairs and landing on a child.

MOTOR VEHICLES

PASSENGER FATALITY

Case Study 3-1

This 11-year-old boy was riding in the car with his mother when she fell asleep while driving. The car left the roadway and rolled approximately 100 m. The mother was wearing her seat belt and sustained minor injuries. The boy had undone his seat belt; in addition to injuries to the torso and extremities, he suffered extensive head trauma.

Figure3-1-a

Figure 3-1-a. Abrasion and contusion of the right frontotemporal region.

Figure3-1-b

Figure 3-1-b. Extensive subgaleal contusion.

Figure3-1-cFigure3-1-d

Figures 3-1-c and d. Complex fracturing of the vault and base of the skull.

Figure3-1-e

Figure 3-1-e. Thin subdural hematoma with subarachnoid hemorrhage over the convexities and cerebral edema.

TRAFFIC-RELATED PEDESTRIAN FATALITY

Case Study 3-2

This 9-year-old boy was playing in the yard with siblings when an automobile crossed the roadway and struck the children.

Figure3-2-a

Figure 3-2-a. Child struck by passenger car.

Figure3-2-b

Figure 3-2-b. Extensive lacerations, abrasions, and contusions of the head, trunk, and extremities.

Figure3-2-c

Figure 3-2-c. Large gaping laceration of the left parietal scalp.

Figure3-2-d

Figure 3-2-d. An associated depressed skull fracture.

There was also an atlantalooccipital separation fracture with partial transection of the pons.

NON–TRAFFIC-RELATED PEDESTRIAN FATALITY

Case Study 3-3

This 1-year-old girl was run over in a driveway by a sport-utility vehicle that was being backed up by her father. She was struck by the right rear tire. Her injuries were limited to the head.

Figure3-3-a

Figure 3-3-a. Tire-tread-patterned area of abrasion and contusion of the left forehead and face.

Figure3-3-b

Figure 3-3-b. Fractures of the vault and base of the skull.

Figure3-3-c

Figure 3-3-c. Subarachnoid hemorrhage and extensive cortical contusions.

Case Study 3-4

This 1-year-old boy was in the care of an unrelated adult caregiver, along with 5 other small children. She put the children into a van for a trip and then got out to take something into the house. When she returned, she got in the van and started to back down the driveway. She felt a bump but continued driving until she saw the boy in front of her on the driveway. Extensive injuries of the head, torso, and extremities were seen at autopsy.

Figure3-4-a

Figure 3-4-a. The boy, after he was run over in the driveway.

Figure3-4-b

Figure 3-4-b. Extensive abrasions, maxillary fracture, and right parietal and occipital scalp laceration.

Figure3-4-c

Figure 3-4-c. Compound calvarial fracturing with extrusion of the brain.

FALLS ONTO CHILDREN

BY CAREGIVER

Case Study 3-5

This 1-year-old boy was climbing up a set of stairs when he fell. His father rushed over to pick him up but stumbled and fell down the stairs with the boy. The father came to rest on his back on top of the boy, crushing him.

Figure3-5-a

Figure 3-5-a. Subgaleal contusion in the inferior right occipital scalp seen at autopsy.

Figure3-5-b

Figure 3-5-b. Complex eggshell-type fracture of the right posterior fossa.

Figure3-5-c

Figure 3-5-c. Epidural hematoma on the right posterior fossa.

Figure3-5-d

Figure 3-5-d. Subarachnoid hemorrhage and contusion of the right cerebellar hemisphere and cerebral edema.

No retinal hemorrhages were seen.

BY HORSE

Case Study 3-6

This 10-year-old boy was riding a horse that was startled. The horse stumbled and fell, landing on the boy’s head. The boy died in the hospital approximately 22 hours after the event.

Figure3-6-a

Figure 3-6-a. Small abrasion on the right side of the forehead.

Figure3-6-b

Figure 3-6-b. Linear fracture of the right temporoparietal region with extension into the base of the skull.

Figure3-6-c

Figure 3-6-c. Epidural hematoma.

There was also a subgaleal contusion and cerebral edema with uncal and tonsillar herniation.

BY TELEVISION SET

Case Study 3-7

This 2-year-old girl lived in her grandparents’ basement with her mother. The mother went to take a shower and left the girl alone. A 27-inch television set was sitting on top of a 5-drawer dresser. The mother reportedly heard a noise and came out to discover the television on top of the child. At autopsy there were contusions of the right arm and leg in addition to head injuries.

Figure3-7-a

Figure 3-7-a. Area of irregular abrasion on the left forehead.

Figure3-7-b

Figure 3-7-b. Small laceration at the lateral corner of the left eye.

Figure3-7-c

Figure 3-7-c. Scalp and subgaleal contusions in the left frontal and inferior occipital regions.

Figure3-7-dFigure3-7-e

Figures 3-7-d and e. Transverse linear skull fracture extending from the right occipital region through the right posterior fossa to the left anterior fossa.

Figure3-7-f

Figure 3-7-f. Right occipital subdural hematoma with irregular subarachnoid hemorrhage in the right occipital and left frontal regions, cortical contusions of the right occipital pole and cerebral edema with herniation.

Chapter 4

BIOMECHANICS

Betty Spivack, MD

An understanding of mechanisms of injury requires a familiarity with concepts of physical mechanics. In this chapter, we will review the general principles determining the response of the brain and skull to physical forces, apply those principles to understanding the injuries seen in abusive head trauma, and differentiate these from mechanisms of injury in common childhood accidents.

BASIC MECHANICS

THE PHYSICS OF LINEAR MOTION

Objects will continue in linear motion with constant velocity, measured in meters per second, unless a force is applied to alter that motion. Hence, an object in motion will tend to remain in motion and an object at rest will tend to remain at rest. This is the principle of inertia, or resistance to change of linear velocity. Mass, measured in kilograms, is the measure of this resistance to change in motion. The force, measured in newtons, needed to change linear velocity is proportional both to the mass and the acceleration, or change in velocity per unit time, measured in meters per second. This relationship is summarized by the following equation:

p29-1

After a force has been applied, the linear velocity of objects will change as a result of the acceleration induced by that force. The relationship between acceleration, duration of acceleration (t), original velocity (v0), terminal velocity (vt), and distance traveled (d) is expressed in the following groups of equations:

p29-1

Work, measured in joules or newton meters, is the result of force applied through a distance. Energy, also measured in joules, is the capacity to do work. In the context of trauma, the work performed on the body is responsible for the injuries that are seen. For a given injury to occur, sufficient energy must be available to do the necessary work on the body. Energy may arise from motion (kinetic energy) or position (potential energy). Potential energy represents the effect of acceleration caused by gravity should the object fall from a height (h). The acceleration resulting from gravity (g) is 9.8 m/s². The total energy of a system, kinetic and potential, will remain constant throughout object movements