What is failed back syndrome (FBS) and how is it managed?
FBS is the failure to return to normal activities and/or lose pain complaints after lumbar surgery. The incidence is between 15% and 30%. The etiology of FBS includes complications (scarring) from the surgery or diagnostic procedures, incorrect diagnoses, inadequate surgery, and new pathology.
Treatment modalities focus on decreasing inflamma-tion around the nerve roots and/or decreasing scar tissue that may be causing irritation of the nerve roots. Pain management techniques that have been utilized for FBS include:
· Selective nerve root blocks with local anesthetic and steroid.
· Caudal/epidural steroid injections below or above the surgical scar.
· Epidurolysis, which lyses adhesions in the epidural space. This can be accomplished either mechanically with a spring-tipped catheter or chemically with large volumes of steroids, hyaluronidase, local anesthetic, and possibly hypertonic saline, which have a local anesthetic as well as anti-inflammatory effect.
· Epiduroscopy, which allows for lysis of adhesions and specific steroid injections under direct visualization.
· Spinal cord stimulation has also been used for FBS with varying success. In properly chosen patients, one can expect that 50% of the patients will have a 50% decrease in pain after insertion of the stimulator.
· Chronic analgesic regimens are frequently prescribed for patients with FBS in conjunction with the more definitive invasive techniques.