There are natural curves of the spine because of the mobility that the vertebral bodies allow. From the side the neck (cervical spine) has a lordosis (swaying in); the upper back (thoracic spine) has a kyphosis (sway out); the lumbar spine (lower back) has a lordosis. These curves provide a balance when a person is standing and allow the head to be upright.

If there is an excessive curve in one region of the spine the other regions compensate so the person’s head remains upright. A loss of lumbar lordosis is call flatback.

Someone with Flatback Syndrome often experiences thigh and back pain. The person may get tired easily and in extreme situations have difficulty standing upright – standing with their hips and knees bent in order to get their head upright. There may be symptoms of sciatica (pain in the buttocks and leg) that are associated.

Causes of Flatback Syndrome

Flatback syndrome can be caused by previous spinal instrumentation.The rods flatten the normal lordosis of the lumbar spine. Patients may do well for years after their surgery, but eventually the discs below the fusion wear out and the person is unable to stand upright.
Other causes of flatback syndrome:

  • Degeneration of the intervertebral discs occurs with age. As the discs degenerate in the lower back, the lumbar spine stiffens and there is loss of normal lordosis.
  • Compression fractures of the lumbar vertebral body, often due to osteoporosis, can lead to loss of lumbar lordosis.
  • Ankylosing spondylitis is a chronic inflammatory arthritic disease that causes stiffness of the entire spine and can lead to loss of lumbar lordosis.


Conservative treatment may be the first choice in flatback syndrome. This is typically physical therapy. This may provide a relief of symptoms of flatback syndrome. If, however, the structural problem is severe enough then surgery is likely indicated.

The goal of surgery is to correct spinal alignment. To achieve this, multiple wedge shaped cuts (osteotomies) are made in the vertebrae of the affected area. The placement of the osteomies is essential in correcting the flatback. Spinal instrumentation is used to hold the corrected alignment while the bones fuse and heal.