Rgirl, you are being paged on the Michelle's Back Pain thread in the Edge (post #21). MM
That's an RGirl question if I ever heard one! Hockeyfan228
Hmm, methinks I come to mind because of all those aching backs people get from trying to read those looooooongwinded Rgirl posts

Don't worry on this one. I'll use this emoticon :agree: to let the reader know the big insurance companies have given their stamp of approval that the post is not of such length to cause back pain in the average reader. But I'm only covered for length. Nobody would even touch me for content--surprise, surprise.
And sorry I'm so late in responding, but my back's been killing me. (Who didn't see that one coming a mile away?)
Actually, Piel already answered the question about layback spins and back problems extremely well. Moot though anything I say may be, I'll add a few more things about spins and the spine.
Layback spin: No matter when you arch the back, the spine can only bend backwards in two sections of the four sections of the spine. The four sections are the seven cervical vertebrae, 12 thoracic, five lumbar, and the five fused (all bone) vertebrae of the sacrum. (There are anatomical variations with some people have an additional vertebra in one area, but I'll just stick to what most people have.) So when a skater arches the back, whether it's for a layback, an Ina Bauer, a spiral, whatever, only 10 of the movable 24 vertebrae contribute to the arch. Because of variations in torso length, ribcage size and placement, shoulder placement, and other things, it may look as if the thoracic spine is arching too, but the thoracic vertebrae are skeletally designed so they cannot arch. For more detailed info as well as illustrations go to "Spinal Anatomy and Back Pain" at
http://www.spine-health.com/topics/anat/a01.html
As for other spins, e.g., the various sit spins, these too can cause strain on the back. If it's a straight back sit spin, a lot of stress is put on the spine to maintain the correct position and control the torque (twisting force) as one spins. If it's a face-to-knee sit spin, the extreme forward flexion of the lumbar spine plus the torque causes even more stress. Add a twist to either position, and the muscles, tendons, ligaments, and discs (the latter of which are actually ligaments) all experience more strain.
Then there are all the spin variations and combo spins. As any skater will tell you and as Dick Button hammers home every season, spins require a great deal of energy. But it's a different kind of energy than the explosive kind required by jumps or the endurance kind required by maintaining speed while stroking. (Won't go into ATP-PC, anaerobic, and aerobic energy; skating uses all three overlapping anyway.) Spinning requires an energy that is somewhat akin to holding a pose for a long period, such as that required for an artist's model, except of course you've got the muscles working even harder to maintain all the factors of the spin. This builds up a lot of pressure especially within the lumbar discs of the spine. So even a straight-up scratch spin is hard on the back.
Still, IMO, the hardest thing on the back in skating are the jumps. However, with the COP rewarding difficulty for every element, I think the main reason we're seeing back injuries in some of the top all-around skaters is the combined effect of pushing the inside of the envelope on everything. It's a high-wire endeavor and I just hope that skaters and their coaches find ways to balance health and safety with risk.
Rgirl