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This is MORNING EDITION from NPR News. I'm Renee Montagne.
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And I'm Steve Inskeep.
Today's personal health report examines one of the most common complaints in medicine, people who suffer from an aching back. We're starting a series on back pain. And first, NPR's Richard Knox tells us why the spine is so prone to problems.
RICHARD KNOX reporting:
Henry Dietrich Fernandez is an architect who lives in Cambridge, Massachusetts. He sees the human spine as a magnificent piece of architecture. It can bear great weights, but also flex.
Mr. HENRY DIETRICH FERNANDEZ (Architect) The best analogy is the steel skeleton of a high rise, having to bend and shift and accommodate itself to dynamic forces like the wind.
KNOX: But it's the spine's complexity that makes it vulnerable.
Mr. FERNANDEZ: Because of its flexibility and because of its multi-jointed structure there are so many opportunities for so many things to go wrong.
KNOX: He knows what he's talking about. Four years ago, Fernandez was crossing the street when he was hit by a car. It wasn't a big accident, but ever since he hasn't had a day without back pain.
Mr. FERNANDEZ: It's with me all day long. No surgery or drugs can fix it. It's just with me now for life.
KNOX: He has lots of company. Eight out of 10 people will suffer back pain at some point. Most can't point to a specific injury. The pain just seems to come out of nowhere. Dr. Augustus White of Harvard Medical School has spent most of his life treating back pain. He says most of it can be traced to spinal deterioration that starts surprisingly early in life.
Dr. AUGUSTUS WHITE (Physician, Harvard Medical School): The changes occur between ages 30 and 50, and that's where most of the back pain is, although there is plenty of it before 30, and there is certainly plenty of it afterwards.
KNOX: Much of the pain comes from the disks, especially in the lower back. Like a stale jelly donut, these shock absorbing disks dry out and change shape.
Mr. WHITE: Narrowing of the disks, fragmentation of the disks, drying of the nucleus, the jelly part of the jelly donut, are all aging processes and it happens in varying degrees to all of us.
KNOX: When the disk bulges or ruptures, the cushioning jelly can push into the spinal canal and press on the nerves. Another source of back pain is the facet joints. These are the meeting points of wing-like projections on the back of each vertebra.
Mr. WHITE: These little facet joints can act like arthritis just about anywhere in the body. The same way the knee joint can be painful or the hip joint can be painful, these little facet joints can be painful.
KNOX: And then there is spinal stenosis; that's the narrowing of the spinal canal where nerves run through it or the passages in each vertebra where the nerves exit the spine. Many things can cause it, injury, arthritis. Sometimes the ligaments that hold the spine together get floppy and fold over. White says imaging devices like CT and MRI, offer detailed pictures of all these problems, but that often doesn't reveal which changes explain the pain.
Mr. WHITE: Some of them become painful and some of them don't, and that's where the big question is. We tend to assume that the pain is coming somehow from the degeneration, but we don't have good proof of that.
KNOX: And because diagnosis is so often difficult, White counsels caution and patience in searching for treatments.
Richard Knox, NPR News, Boston.