Introduction
The rate of failed lumbar spinal surgeries is variable, from 10 to 40 percent. Spinal fusion failure rates lie between 19 and 24 percent. Failed back surgery syndrome is a term used to describe a variety of conditions that cause persistent lower back pain after one or more spine surgeries. When surgical outcome does not meet pre-surgical expectations of the patient and the surgeon, it is described as failed back surgery syndrome.
Causes of Failed Back Surgery Syndrome
- Poor patient selection
- Wrong procedure
- Poor technique
- Surgical failure
- Progressive disease
Prior to back surgery you should be informed of possible complications and failure rates of the surgical technique used to treat your back problem. Poor patient selection by the physician seems to be the most common cause of failed back surgery. Intrinsic psychological factors cause certain patients to exhibit abnormal pain behavior. Analysis of psychological factors prior to surgery can predict spinal surgery outcome in 82 percent of patients.
A misdiagnosed or overlooked element of spinal pain may be missed during diagnosis. Careful correlation of radiographic evidence and physical examination must agree before surgery is attempted. Along with misdiagnosis, surgery done on the incorrect site or poor surgical technique can lead to failed back surgery syndrome. Spinal disc removal or spinal fusion done at the wrong level will not correct a painful back and poor surgical technique may cause additional pain.
Sometimes, surgical failure occurs when the goal of the surgery cannot be fully completed as determined by the surgeon. Surgical techniques used to decompress pinched nerves may cause destabilization of the bones, thus causing new areas of pain and inflammation. Also, the technique used for surgical decompression may fracture smaller bones within the surgical area and cause complications.
Ongoing spinal degeneration processes may be accelerated by changes in the bone biomechanics after surgery. Recurrent slipped spinal discs can occur in up to 15 percent of spinal surgeries. Nerve roots may become trapped in post-surgical scar tissue and become less adaptive to changes during aging. In spinal fusion surgery up to 25 percent of patients 10 years after surgery will have degeneration on an adjacent vertebra.
Conservative Management
- Medications
- Physical therapy
- Behavioral therapy
Over 60 different types of pharmaceuticals, more than 30 manual therapies, at least 20 different injection therapies and a multitude of exercise or psychological therapies exist for treatment of failed back surgery syndrome. Medications should be prescribed not only to reduce back pain, but to enable proper exercise therapy. Simple pain medications include acetaminophen, anti-inflammatory medications and COX-2 inhibitors. COX-2 inhibitors will inhibit COX-2 enzyme, which is responsible for pain and inflammation.
Sometimes, anti-neuropathic agents will be prescribed for nerve pain and anti-depressants for chronic pain of failed back surgery syndrome. Opioids can help treat pain in patients who cannot find relief with other medications, but is currently a controversial medication for back pain.
Intervention Management
Local anesthetic blocking techniques can be used to determine the origination of failed back surgery pain. An irritated nerve or surgical adhesion scarring may need to be cut to produce sustained pain relief. Also, the use of steroid injections is often used to relieve spinal pain. Steroid injections can help reduce pain by 50 percent, but only if proper radiographic needle placement occurs during the injection. Radiographic allows a comprehensive view of post-operative anatomical changes and promotes proper needle placement for optimal pain treatment.
Surgical Treatment
Surgical implantation of an electrical device, to deliver spinal cord stimulation current, can be used to treat failed back surgery syndrome. Spinal cord stimulation may reduce pain and medication usage. Implantation of pain medication delivery devices may be indicated for treatment failed back surgery syndrome, but efficacy has not been completely determined for this system. Lastly, revision surgery may be needed to correct problems with ongoing pain.
