-
What is the Mechanism of Spinal Deformity in People with Abnormal Vertebra?
As stated before, the most significant factor that causes the spine to bend is the asymmetrical growth of the abnormally formed vertebrae.
These abnormal formations can be classified as follows:
- Type I- Hemivertebrae caused by a deficiency in vertebral formation or incompletely formed vertebrae
- Type II- In this type, the vertebrae initially form as a single block and then undergo division, however due to a failure in division they remain connected at one (unsegmented bar) or both sides (vertebrae abnormally linked to each other, block vertebra)
There may be conditions where the two types coexist.
Hemivertebrae cause one side of the spine to grow more than the other. While the vertebrae connected to each other (block vertebra) prevent growth on the same side, the other side continues to grow normally, and causes the spine to bend.
Although the abnormal vertebrae are present since birth, the curve may not be visible in infancy. Curve occurs with growth. However, despite growth, the affected spine may not curve at all or curve minimally. Moreover, in spines where there are more than one abnormal vertebra and the abnormalities are distributed in a such a way that they balance each other, the overall result is a decrease in trunk growth rather than an increase in curve. The curve may increase slowly prior to the growth spurt during puberty.
Signs include:
- A curve to the side or abnormal gibbosity or abnormal swayback
- Skin abnormalities in the back, such asincreased hair growth, dimples, color changes
- Abnormal arms or legs
- Asymmetric shoulders, waists or hips
- Disproportionate shortness of the trunk compared to the legs
- Balance disorders
- Back prominence seen when the person bends forward