Congenital forms of scoliosis make up a small subgroup of cases that result from prenatal defects in the formation of the vertebrae.
These defects are of different kinds: some patients present with one or more wedge-shaped hemivertebrae (partially formed vertebrae) at some point along the spine, others will have several vertebrae fused together into a single bone, and some present with a combination of both these conditions.
These defects may be single or multiple and can occur at different levels of the spine.
How it evolves
The evolution of congenital scoliosis is quite variable.
The form characterized by the presence of a single hemivertebra carries typically a higher risk of progression compared with the other types, although to a large extent the evolution depends on the overall balance of the individual spine.
If the spine is well balanced, the condition will be less likely to progress.
Furthermore, very often, the progression is not in the curved parts of the spine that present the malformation, but rather in the adjacent ones.
How it is treated
The treatment options for congenital scoliosis are, up to a point, similar to those available for idiopathic scoliosis, with the exception of exercises, which obviously cannot be taught to very young children.
Bracing influences the growth of the vertebrae and works by countering the forces that caused the deformity to appear.
Essentially, the brace acts by unloading the vertebrae thus enabling the less developed portions of the vertebrae to grow, therefore the brace works in the opposite direction to the mechanical causes of the deformity.
Even though bracing may sometimes result in compensatory deformations at the level of initially normal adjacent vertebrae, bracing can ensure a better balance of adjacent sections, allowing patients to reach the end of their growth with a well-balanced spine, avoiding thus the mechanical events and phenomena associated with progression of the deformity.
In the presence of hemivertebrae, it is sometimes decided, very early on, to opt for surgery in order to remove these deformed vertebrae and thus prevent or limit the progression of scoliosis.
It should be understood that in severe cases it will likely be necessary to perform a fusion.
This procedure, which serves to stabilise the spine, involves the placement of special metallic fixation devices that block the vertebrae in position.
Hemivertebra resection (the removal of a wedge-shaped vertebra) is performed to create the conditions that will allow the spine to grow straight.
In theory, this procedure will spare the patient the need to undergo further treatment later on (be this bracing or more surgery); at present, however, the long-term results necessary to confirm the correctness of this theory are lacking.
It is considered that this procedure should be applied mainly in patients under two years of age, i.e., before compensatory phenomena have had a chance to develop in the neighbouring vertebrae.