Flatback Syndrome

Flatback = the loss of the normal lumbar lordosis
Syndrome = a collection of symptoms that occur together

Flatback syndrome is a condition in which the lower spine loses some of its normal curvature. It is a type of sagittal imbalance, or front-to-back imbalance in the spine.

Normally, the spine has several gentle front-to-back curves. The lumbar (lower) spine has a lordosis, or inward curve. The thoracic (middle) spine has a kyphosis, or outward curve, and the cervical spine (neck) has a lordosis. These curves usually work in harmony to keep the body’s center of gravity aligned over the hips and pelvis.

If the lumbar lordosis is lost, the center of gravity can be put too far forward. This is the case in flatback syndrome.


Flatback syndrome can cause difficulty standing upright, chronic pain, and difficulty with daily tasks.

In order to stand upright, a person with flatback syndrome must contract the back muscles, and possibly flex at the hips and knees. These maneuvers may temporarily help a person stand upright, but over time, they may result in severe pain.


To determine the degree of flatback syndrome, the doctor may order an X-ray–a test that produces images of the spine and other bones and tissues using invisible electromagnetic rays. This may be a long cassette upright scan that shows the entire spine in a single image. The doctor may also order additional diagnostic procedures to obtain a more detailed image of the spine:

  • Magnetic resonance (MR) imaging scan: uses a magnet and radio waves to provide detailed images of the spinal cord. Can help identify whether the spinal cord (the bundle of nerves connecting brain and body) has been affected by the spinal curvature.
  • Computed tomography (CT) scan: uses X-rays and a computer to produce detailed images of the body. CT scans are more detailed than general X-rays.

Risk Factors

Flatback syndrome may be caused by degenerative disc disease, compression fractures, or ankylosing spondylitis.

Flatback syndrome may also develop after a surgical procedure such as a laminectomy or a lumbar spinal fusion that does not maintain the normal curve of lordosis.


Many patients may be treated without surgery. Initially, nonoperative measures will be recommended. These measures include physical therapy, including gait and posture training, exercises, and pain medications.

If nonoperative measures do not provide symptom relief, if structural problems develop as a result of the lack of curvature, or if the misalignment is severe, surgery may be required. The goals of surgery are to provide pain relief, correct the spine, and prevent the misalignment from getting worse. In flatback syndrome, this is accomplished by adding curvature to the lumbar spine.

Procedures that treat flatback syndrome include osteotomy and pedicle subtraction osteotomy. In these procedures, a surgeon removes bone from the back of the lumbar spinal column. The surgeon can realign the bones of the spinal column, introducing the necessary lordosis.

Following one of these correction procedures, the surgeon is typically required to re-establish the strength and stability of the spine through a spinal fusion and fixation. In a fusion procedure, the surgeon places grafting material between two or more bones of the spine, encouraging them to fuse (grow together) into one solid bone. In a fixation procedure, the surgeon inserts hardware like screws and rods that hold the spine in place while the bones fuse.