AUBURN – Four doctors who examined Nathaniel Allen in the hours before he died testified Monday that it would have taken a “massive amount of force” to cause the brain injuries that killed the toddler.

The doctors gave examples of various accidents that could produce such force: a car accident, a skiing accident, a blow to the head with a bat or some other hard object or a fall down a flight of stairs in a baby walker.

When asked if multiple falls in the tub or on a carpeted floor could produce enough force to cause the boy’s injuries, the doctors replied that it would be extremely rare, especially given that they didn’t note any skull fractures or bruises on the boy’s head.

“I’d expect to see at least a goose egg,” testified Dr. Charles Grimes, a radiologist who examined the 21-month-old at Maine Medical Center on the morning of Feb. 15, 2003.

Nathaniel Allen died later that day after it was determined that the swelling and bleeding in his brain was so severe that he would never survive without life support.

Two weeks later, his adopted mother, Sarah Allen, was charged with causing his death by shaking him with so much force that it tore the blood vessels in his brain.

A 30-year-old former hair stylist from Lisbon Falls who stopped working to take care of her only son, Allen is standing trial in Androscoggin County Superior Court.

On Monday, the fifth day of her trial, a lineup of doctors who treated Nathaniel at Maine Medical Center in Portland took the stand to answer questions about their observations of the boy’s external and internal injuries and their opinions about how those injuries could have occurred.

They all concluded that child abuse – in this case, a violent shaking – was the most probable cause, and they agreed that Allen’s explanation of how the boy had fallen several times did not make sense.

“Could a fall in the tub cause that type of bleeding?” Assistant Attorney General Lisa Marchese asked Dr. Eric Gunnoe, a pediatric intensive care doctor.

“It has to be a fall from a substantial height onto a hard surface,” Gunnoe replied. “Falls less than 4 feet onto any surface do not cause substantial injury.”

Dr. Lawrence Ricci, a child abuse expert who assisted with the investigation of Nathaniel’s death, concluded, “I don’t believe any falls could have accounted for those injuries.”

The doctors testified that the boy didn’t have fractured limbs or any bruises on his spine, chest or arms. While they acknowledged that these types of external injuries are commonly seen on babies who are violently shaken, they testified that they do not occur in every situation.

Ricci testified that he also noticed small bruises on the back of both of Nathaniel’s hands. Unlike with common childhood bruises on the knees, chin and shins, he said, it is extremely unlikely that an accident or fall would bruise the back of a child’s hand.

“Could they be consistent with grabbing the child?” Marchese asked Ricci.

“They could be,” he replied.

Ricci testified that his suspicion that Nathaniel was abused came from a “constellation” of signs, including Allen’s description of the boy as defiant and passive-aggressive. He referred to her choice of words as a red flag.

Allen’s trial is expected to last until the middle of the week.

It will continue Tuesday with more state witnesses taking the stand. After the state finishes its case, defense attorney Verne Paradie is expected to call his own medical experts to dispute the findings of the doctors who testified Monday.

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