How Long Can You Wait to Have That Spinal Fusion Surgery Before It's Too Late?
Can you wait too long to have spinal fusion surgery? Some research has shown that waiting too long may mean a poor result -- the patient doesn't get the pain relief hoped for. But how long is too long? That's the focus of this study from Great Britain.
Most people recover from back pain with a little time and attention. Those who don't are often treated with medications such as pain relievers or antiinflammatories. Some seek the help of a chiropractor, physical therapist, acupuncturist, or massage therapist. If the symptoms haven't gone away after three months, the condition is becoming chronic.
Disc degeneration is a common cause of chronic low back pain. The pain can become so constant and intense that surgery to remove the disc and fuse the spine at that level becomes the next step in treatment. To find out if waiting more than six months would have an effect on the results of spinal fusion, the authors followed a group of 209 patients for a minimum of two years. Most of the patients had painful symptoms much longer than six months -- some as long as 28 years!
Data was collected before and after surgery using a variety of tests and measures. X-rays were used to look for evidence that the fusion was solid and successful. Patients filled out several different surveys with questions about pain, function, disability, attitude, anxiety, depression, and so on. All tests were repeated at regular intervals (first at six weeks, three months, and six months after surgery; then every year thereafter).
The authors found that everyone got better -- even the patients who had chronic pain for years and years. And the improved pain and function continued. Despite the common belief that waiting too long means surgery won't help, there aren't many studies to support or disprove this idea. This study may be the first one to really address the issue.
The idea that chronic pain can't be changed with surgery comes from the belief that over time pain messages get so engrained in the central nervous system (spinal cord and brain) they can't be turned off. Scientists refer to this as a central pacemaker. The pacemaker gets turned on when persistent and continuous pain messages are sent from the nerves to the spinal cord and then up to the brain. The result is called centralization of pain.
But this belief that a long period of pain leads to a poor prognosis wasn't supported by the results of this study at least. Even taking into consideration factors like mental health (depression, anxiety) and general health (presence of other diseases or conditions) didn't change the fact that the majority of these patients got better after surgery.
Did they just beat the odds or was this an outcome that can be repeated? Since patients were still reporting positive results (pain relief, improved function) up to five years later, it looks like the results are real and long lasting. The authors of the study do point out that in their patient selection they were careful to select patients with just one pain diagnosis. No one in the study had other causes of chronic pain like fibromyalgia or arthritis.
The particular approach used in the spinal fusions for all of these patients was one called posterior lumbar interbody fusion or PLIF. The procedure was done from the back of the spine. An open incision was made, the disc removed, and the bone on either side of the disc (lamina and facet joint) was cut away. The bone taken out was ground up and used to pack the middle of the disc space before inserting a device called a cage. One cage went on either side of the bone chips. Then a plate and screws were used to hold everything together until bone filled in to complete the fusion.
The authors conclude that at least for patients with disc degeneration, a posterior lumbar interbody fusion (PLIF) works well even when the patient's symptoms have been present for a very long time. Chronic and severe pain is not a reason to avoid spinal fusion using the PLIF method. This study also brings the theory of centralization of pain into question. Future studies are needed to further investigate these new findings.
Laurence A. G. Marshman, MD, FRCSN, et al. Does Symptom Duration Correlate Negatively with Outcome After Posterior Lumbar Interbody Fusion for Chronic Low Back Pain? In Spine. March 2010. Vol. 35. No. 6. Pp. 657-665.