Dr. David KoivurantaDoctor Of Chiropractic, Toronto Neck and Back Pain Clinic · I Prevent the Work Injuries I Treat Daily | Clinical Ergonomic Assessments for HR & H&S | GTA

Your Spine Is NOT Straight (Here’s Why) | Chiropractor Explains

12 Apr 2026 · 0 min

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0:28

In this educational video, Dr. David Koivuranta explains that the human spine, while appearing straight when viewed from the front, actually contains four distinct sagittal curves: the cervical (neck), thoracic (mid‑back), lumbar (lower back) and sacral/pelvic (tailbone) curves. He describes how these curves develop over a person’s life: newborns are born with a single C‑shaped curvature, and as they grow, the spine remodels into the four‑curve adult configuration that provides optimal shock absorption and balance. The video uses visual models to contrast the apparent straightness of the spine from a front‑to‑back view with its true three‑dimensional shape, emphasizing why understanding this anatomy matters for posture, injury prevention, and chiropractic care.

This is your spine, and this is almost the same size and shape as an adult spine. And from the side, this thing has got 4 curves in it. It's got a curve in the neck, curve in the mid-back, curve in the lower back, and a curve in your tailbone or pelvis. From front to back, we like to see that it's straight up and down. But these curves that are here weren't always here. When we were born, we were actually shaped like a letter C. We only had one big curve