NATION In shaken-baby syndrome debate, studies disagree

Does shaken-baby syndrome exist? Some say no.
ASSOCIATED PRESS
When 7-month-old Natalie Beard's body arrived in the autopsy room, there were no outward signs of physical abuse. No broken bones, bruises or abrasions.
But behind her pretty brown eyes and beneath her fine dark-brown hair, there was chaos.
Both retinas were puckered and clouded red. And there was acute bleeding outside and beneath the brain's outer membrane -- the kind of bleeding most often associated with a burst aneurysm.
To forensic experts, these were classic signs that Natalie was shaken to death.
The common wisdom in such "shaken-baby" cases was that the last person with the child before symptoms appeared was the guilty party, and a Wisconsin jury convicted baby sitter Audrey Edmunds of first-degree reckless homicide.
Edmunds is 10 years into her 18-year prison sentence, and she's seeking a new trial.
In the decade since her conviction, her attorneys say, many experts have studied the physics and biomechanics of shaken-baby syndrome and have concluded that shaking alone could not have produced Natalie's injuries without leaving other evidence of abuse.
Among those questioning the diagnosis is Dr. Robert Huntington III, the forensic pathologist who examined Natalie's body and whose testimony helped put Edmunds away.
If the trial were held today, Huntington told The Associated Press recently, "I'd say she died of a head injury, and I don't know when it happened ... there's room for reasonable doubt."
Recognition
The syndrome does not lack official recognition.
"Shaken baby syndrome is a serious and clearly definable form of child abuse," the American Academy of Pediatrics declares on its Web site.
According to the National Institute of Neurological Disorders and Stroke, SBS bears a "classic triad" of signs -- brain hemorrhaging, retinal hemorrhaging and brain swelling. Because of a baby's relatively heavy head and weak neck muscles, shaking "makes the fragile brain bounce back and forth inside the skull and causes bruising, swelling, and bleeding, which can lead to permanent, severe brain damage or death," the institute says.
An estimated 1,500 shaken-baby cases were reported in the United States last year, says Toni Blake, a San Diego defense attorney who specializes in the cases.
But 31/2 decades after the term was first used, there seems to be no middle ground in the debate.
"It doesn't exist," contends Dr. John Plunkett, a Minnesota pathologist who began openly questioning shaken-baby following the 1997 involuntary manslaughter conviction of British nanny Louise Woodward, the case that put SBS on the map. "You can't cause the injuries said to be caused by shaking, by shaking."
Many pediatricians disagree.
"People confess to it. So it has to be possible," counters Dr. Suzanne Starling, director of forensic pediatrics at Children's Hospital of The King's Daughters in Norfolk, Va.
She and her colleagues analyzed 81 cases in which an adult confessed to shaking and/or battering a child. In cases where only shaking was admitted, the children were 2.39 times more likely to have retinal hemorrhages than victims of impact alone, they found, "suggesting that shaking is more likely to cause retinal hemorrhages than impact."
Taking sides
Research is split:
UPlunkett, in a 2001 article, concluded an infant could suffer a fatal head injury from even a short fall, and that the injury "may be associated with a lucid interval and bilateral retinal hemorrhage." In other words, symptoms might not immediately follow the injury -- which can be an important issue in fixing blame. In addition, there were other, accidental sources for one of the "classic" signs of SBS, he wrote in the American Journal of Forensic Medicine & amp; Pathology.
UIn a 2003 study, University of Pennsylvania researchers used special dummies to simulate a 11/2-month-old baby being shaken or dropped from various heights. The response to a vigorous shaking was "statistically similar" to that from a 1-foot fall onto concrete or concrete with carpet pad, they found; a fall from 3 feet produced forces nearly 40 times greater.
UBut still-to-be published research using a more advanced infant dummy simulated far greater brain damage than with previous dummies, says Dr. Carole Jenny, a Brown University Medical School professor and chair of the AAP's committee on child abuse and neglect.
UOther studies cited by SBS opponents have suggested that the hemorrhaging and swelling thought to prove shaking can have myriad causes, from dehydration and infection to oxygen deficiency.
Much of the debate has centered on how quickly symptoms begin after a brain trauma. That question was central to the Wisconsin case.
Dr. Thomas Bohan, a forensic physicist and attorney, has tried to get the National Academy of Sciences and the National Institute of Justice to evaluate the medical and legal arguments.