Failed Back Surgery Syndrome

Description

Failed Back Surgery Syndrome is described as a poor outcome that can result from surgery to correct a back problem. The United States, surgeons perform an estimated 300,000 to 400,000 back surgeries annually. Approximately 20% and 40% of these operations are unsuccessful, resulting in pain that is the same or even worse than prior to the surgery.

Causes

  • Scar tissue from surgery
  • Instability
  • Failure of fusion after back surgery, also termed pseudoarthrosis
  • Nerve damage during surgery
  • Arachnoiditis: inflammation of membranes that surround the spinal nerve
  • Disk disease at levels adjacent to the surgery
  • Persistent pressure from spinal stenosis

Symptoms

Recurrent back or leg pain and lack of ability to perform activities of daily living

Diagnosis

The evaluating physician will review prior surgical reports to gather details. She/he may ask you if you are experiencing numbness, weakness or heaviness in your legs. The doctor will also ask you about the location of your pain and its nature in terms of being sharp vs dull, local vs. radiating. Other important questions include whether the pain is worse with standing and walking and if it diminishes when you sit.

During the physical exam, the physician looks for limitations of motion in the spine and weakness in the legs. She/he may ask you to ambulate to view your back as you move. Neurologic exams are likely to be performed to determine if nerve damage is contributing to your symptoms. Sensation is tested by applying a stimulus to the skin. Nerve compression, which may result in weakness, is assessed by having you push back when pressure in applied to your muscles.

Imaging studies include traditional two-dimensional X-rays and a newer three-dimensional X-ray called EOS imaging. EOS imaging can help differentiate whether malalignment of the spine may be a contributing cause of lower back pain.

An MRI may be performed to assess if there are any additional bulging or herniated disks.

A bone scan involves injecting an intravenous tracer that travels to the bones and may highlight fractures not visible on traditional X-rays.

Management

Conservative treatment with physical therapy, medications and counseling should be attempted initially. If such conservative measures fail, interventional pain management procedures can be attempted. These are usually in the form of radiographically guided steroid injections. If steroid injections do not provide sustained relief, a spinal cord stimulator can be considered. This is an implanted device that blocks the transmission of electrical signals from the spinal cord to the brain. An intrathecal pump, which is implanted between the muscle and skin of the abdomen, delivers a small dose of pain medication via a catheter to the intrathecal space and bathes the spinal cord and spinal nerves directly.