There are two main types of scoliosis in adults:
- adolescent idiopathic scoliosis which has progressed into adulthood
- de novo degenerative scoliosis (DNDS)
ADOLESCENT IDIOPATHIC SCOLIOSIS WHICH HAS PROGRESSED INTO ADULTHOOD
As scoliotic curvature does not disappear once skeletal maturity is complete, adult idiopathic scoliosis is simply the result of the progression of adolescent idiopathic scoliosis into adulthood.
Contrary to a widespread belief held in the medical community, AIS can continue to progress in adulthood, mainly because of deterioration of the joints due to ageing. This is referred to as the degenerative progression of idiopathic scoliosis as opposed to growth-related progression.
DE NOVO DEGENERATIVE SCOLIOSIS
De novo degenerative scoliosis exclusively affects ageing adults and is the result of joint degeneration without a prior history of scoliosis. It generally occurs after the age of 50, and can affect up to 32% of the population23, with a preponderance in postmenopausal women.
The symptoms of de novo degenerative scoliosis are often more severe than those presented by idiopathic scoliosis, due to the accompanying joint instability and the fact that it exclusively affects the lumbar region.
For a curvature of the same degree, degenerative scoliosis tends to distort the patient’s posture more than idiopathic scoliosis.
Because DNDS is due to joint degeneration, episodic progression of lumbar curves can attain 4°20-24-28 per year.
COMPARATIVE TABLE OF THE TWO MAIN TYPES OF ADULT SCOLIOSIS
|Adult idiopathic scoliosis||De novo degenerative scoliosis (SDDN)|
|Paediatric idiopathic scoliosis, vertebral deformity||No history of scoliosis, no vertebral deformity|
|Degenerates with age||Results from degenerative changes & instability|
|May or may not present pain||Typically associated with spinal stenosis, claudication (lameness), backache and leg pains, incontinence|
|More stable, progresses slowly||Unstable and can progress quickly|
|Not generally associated with menopause||Generally associated with menopause|
|All types of curves||Less severe lumbar curves, severe front and side postural imbalance|