The term flatback syndrome was first used back in the early 1970s. Surgeons noticed patients who had surgery for scoliosis (curvature of the spine) ended up with a very flat low back area. Instead of the natural lordosis (swayback position) of the lumbar spine, there was a definite flattening of the area.
Flatback syndrome is a postural disorder that results in the patient trying to maintain the face and eyes forward for maximal function. When the low back flattens, the knees bend and the upper spine hyperextends to accomplish this horizontal gaze.
Flatback syndrome can also occur in older adults without scoliosis. Degenerative changes such as disc narrowing and vertebral collapse can lead to a similar problem referred to as lumbar degenerative kyphosis (LDK).
LDK is the most common cause of spinal deformities affecting the lumbar spine in older Asian adults. Field workers who are in a constantly stooped or squatting position are especially at risk.