Saturday, June 6, 2020
Spine Rotation in Scoliosis
I have scoliosis….
So why do I have a rib hump?
Why does my shoulder blade sticks out more on one side?
Why are my ribs in the front different?
These are common questions I hear from patients with scoliosis and their parents and caregivers. So why do these changes to the chest happen? Well it’s the ribs which are causing the rib hump, shoulder blades to stick out on one side and the ribs in the front to be uneven. Why? Well, first we need to understand what happens to the spine in scoliosis. If you look at the radiographs (x-rays) below,
from the top to the bottom, the spine moves to the right, then the left and back to the right. In this sense it looks like a lazy river ride at your local water park.
The lazy river moves right, then left, then right…..just like the scoliosis. However, we are only looking in two planes…and scoliosis is actually a 3-d spine problem. So when the spine curves, it also rotates. So this makes scoliosis more like a water slide than a lazy river. As it curves, it also banks
So if the spine is banking as the spine curves left and right….why does that impact the ribs? Well the ribs are attached to the spine with strong ligaments
Which means if the spine banks or twists, it will also bank or twist the ribs, both in the back and in the front of the chest.
On the convex, or outside part of the curve, the ribs will be pulled backwards, and on the concave side (inside) of the curve, the ribs are pushed forward. Since most scoliosis has a curve to the right on the upper curve, the ribs on the right side stick out more, and makes the shoulder blade wing out more, as in the above two pictures.
Also, if the right ribs are pulled back and the left ribs are pushed forward (pictures above) then the patients will see the ribs on the left side, just below the breast be more prominent (stick out more).
In the next blog post I will show how we improve the rib prominence or deformity during surgery.