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Wed Dec 12, 2007 6:27pm EST By Anthony J. Brown, MD NEW YORK (Reuters Health) - During the last weeks of pregnancy, many women become so large in the middle that they look as though they might tip over. But through evolutionary processes, nature has devised a way to keep them upright on their sometimes swollen feet. In a new study, U.S. researchers show how the lower spine in females has evolved to support the obstetrical load experienced by species that stand upright on two feet, so that the center of balance is repositioned over the hips. "Most previous studies on the evolution of how human mothers have accommodated pregnancy have focused on the pelvis and the problems of birthing; this is the first study to look at how mothers cope with the considerable challenges of stabilization while they are pregnant," senior author Dr. Daniel E. Lieberman, from Harvard University in Cambridge, Massachusetts, told Reuters Health. The normal curvature of the lower spine helps position the trunk above the hips in humans, thereby stabilizing the upper body over the legs, according to the report in the issue of Nature. Pregnancy, however, complicates matters as the weight shifts forward. In their study, Lieberman's team shows how over time the lower vertebrae in human females have become reinforced to allow the exaggerated curved position of the spine assumed by pregnant women when they are standing upright. This position allows the trunk's center mass to remain above the hips. By studying fossils of Australopithecus, the researchers found that these vertebral changes actually preceded the evolution of Homo sapiens. "For me, the biggest surprise was that we can see this maternal adaptation in the fossil record so far back," Lieberman said. "It makes sense that evolution would have favored mothers who were better at coping with these demands, but I didn't expect the fossil record would be good enough to yield such evidence." In future studies, he added, "I think we need to look more at the costs of this adaptation and how it relates to the back problems that so many of us regularly experience." SOURCE: Nature, December 13, 2007.

Spinal Cooling Key To Everett's Recovery BUFFALO, N.Y., Sept. 13, 2007 -------------------------------------------------------------------------------- (CBS/AP) Doctors are following the playbook in treating Buffalo Bills football player Kevin Everett's severe spinal cord injury except in one notable regard: pumping icy cold saline into his veins to try to prevent further damage. Although the treatment is experimental, it is more science than science fiction, and also is being tried on stroke and brain injury patients. Everett's prognosis remains uncertain. His doctors were encouraged by signs on Tuesday that he could move his legs and arms - a day after saying he stood little chance of making a full recovery. They also have said that his spinal cord was intact rather than severed - a very good sign. Doctors say that it is far too soon to know whether he will be left with any paralysis or its extent. "Walking out of this hospital is not a realistic goal, but walking may be," Dr. Andrew Cappuccino, the team's orthopedic surgeon, said at a news conference in Buffalo on Wednesday. "We have every hope and anticipation he will walk," said Dr. Barth Green, chairman of the Department of Neurological Surgery at the University of Miami's Miller School of Medicine, who has been consulting with doctors in Buffalo. The procedure, while experimental, is not new and, according to Dr. Green, is based on years of laboratory work, capped by the quick, collective efforts of physicians and health professionals who attended Everett once he fell. The reason Everett's situation has improved, Dr. Green suggested, was because the cooling has been applied so quickly: "It's definitely the first time it's ever been done so early after an injury. "He was handled properly," Dr. Green told CBS' The Early Show. "He was rushed into an ambulance, properly positioned. They dropped his body temperature immediately 15 minutes after the injury, which is a world record. And all that came together with good surgery and good care." Everett suffered a fracture and dislocation of his spinal cord in the neck area during a game Sunday night against the Denver Broncos. Watching it on television from home was Dr. W. Dalton Dietrich, scientific director for the Miami Project, a spinal cord program affiliated with the Miller School of Medicine. The program is among several in the United States that has led research into moderate hypothermia, or cooling the body a few degrees to try to limit swelling, inflammation and the cascade of events and chemicals that cause further damage after an initial neurological injury. Dietrich sent an urgent e-mail to fellow neurosurgeon Dr. Green, who knows Buffalo Bills owner Ralph Wilson. Who did what next is unclear, but doctors say Everett received the experimental cooling therapy in the ambulance, even before X-rays and other tests could show the extent of his injury and the treatment he would need. The goal of the treatment is "to cool the tissue a few degrees to reduce its need for oxygen and to reduce its metabolic rate" and limit secondary damage from chemicals the body releases after the initial injury, said Dr. Elad Levy, a University of Buffalo neurosurgeon who treated Everett. On Monday, as Everett's temperature began to rise, doctors decided to try cooling his body again, using a slightly different system. This time, a hollow tube called a catheter was inserted into the femoral vein in the leg near the groin. Cold saline was circulated inside the catheter, indirectly cooling the blood as it flowed through the vein. "We did this here at the University of Pittsburgh in the '70s," but with a different method of threading a catheter directly over the spinal cord, Maroon said. The treatment had to be done within three hours of injury to have any benefit and was extremely cumbersome, he said. For that and other reasons, it was largely abandoned until recently, when doctors have resumed testing it through different cooling methods for stroke and brain injury patients. "There's no reason around the world we don't give patients this treatment where they are," Dr. Green said, "whether they have a heart attack or spinal cord injury, because the paramedics are there within minutes so we have the opportunity." "There are compelling reasons why one might want to try it" in a case like this, said Dr. Gary Steinberg, chairman of neurosurgery at Stanford University. He had no role in Everett's case but has tested the body cooling treatment. "Not a lot is known about it for spinal cord injury," said Steinberg, where it mostly is done in some stroke and head injury cases under an experimental protocol. Other aspects of Everett's care are more routine. He received large intravenous doses of methylprednisolone, a steroid to limit inflammation and swelling, and had decompression surgery to relieve pressure on his spinal cord. Doctors initially operated from the front of his neck, removing the injured disk and bone impinging on the spinal cord, and realigned it. They filled the space where the disk had been with a bone graft - whether from a cadaver or his hip isn't known - and put in a titanium plate to stabilize the neck area. Surgeons then turned him over and operated from the back of his neck, fusing the vertebrae above and below the fracture, and putting in four screws and two small rods. Long-term results from such operations can vary widely, said Maroon, the Steelers' surgeon who published a paper in the April issue of Journal of Neurosurgery on this topic. He has operated on about 30 athletes. But whatever the extent of Everett's recovery, a return to his career on the field is not likely, said Dr. Joseph Maroon, team neurosurgeon for the Pittsburgh Steelers and a University of Pittsburgh Medical Center specialist who was consulted on Everett's case. "If he ever does regain function, no neurosurgeon would ever permit him to play football," Maroon said. On Wednesday, Everett was successfully removed from the respirator though doctors say it could be a struggle to keep him breathing on his own. A stroke and blood clots in his legs are other possible complications they are trying to prevent. He showed more ability to move his legs and a little more in his arms, but has no movement or function at all of his hands. He is getting nourishment from a feeding tube, and his mother is at his side. "She understands that this is a life-changing event," and that "the story will change over months to years," said Dr. Kevin Gibbons, another University of Buffalo neurosurgeon who has been treating Everett. AP Medical Writer Marilynn Marchione contributed to this report