People with a herniated intervertebral disc may find the “To operate or not to operate?” question especially difficult. Some 80 to 90 percent of those with classic signs and symptoms of disc herniation will feel better within six to 10 weeks of the onset of pain using only minimal, noninvasive treatment. Unfortunately, there is little you can do to predict whether you fall into this lucky majority or the unlucky 10 to 20 percent minority. Studies show that those who undergodiscectomy (the most common surgery for herniated disc) generally experience greater relief more rapidly than those who choose watchful waiting. However, after one year, there is only negligible difference in occupational disability and reported pain levels between those who choose surgery and those who don’t.
Interestingly, where you live can have an impact on whether or not you have surgery. People with chronic low back pain in the United States are five to seven times more likely to undergo surgery for disc herniation than their counterparts in the United Kingdom. Likewise, there are some parts of the United States where surgery rates are higher (or lower) than the national average. And again, when all is said and done, little long-term difference in disability and pain relief exists no matter which course of treatment you choose.
Time appears to be the great equalizer, if not the great healer. Therefore, if your pain is manageable during the first 90 days or so, you may want to take your chances and postpone surgery indefinitely. If your pain is intolerable or preventing you from working or enjoying your normal activities, surgery may be the more desirable choice.
Some neurological testing might help you make up your mind. Part of the routine physical exam for people with lower back pain is the straight leg raise test, in which you lie on your back and raise each leg one at a time. If this triggers pain that radiates down either leg, it is an indication of nerve root compression in the spine. This may warrant an electromyogram and nerve conduction study (EMG/NCS), in which electrical activity along the path of the sciatic nerve is measured to detect abnormalities that would substantiate the suspected diagnosis of nerve root compression. Another test, known as water-soluble myelography, also may be used to confirm disc herniation at a specific site.
Discectomy and laminectomy
Standard discectomy involves removal of the protruding (herniated) portion of the intervertebral disc. It is “open back surgery” in that the surgeon opens up and exposes the affected region of the spine in order to excise the part of the disc that is compressing the spinal nerve (along with any loose disc fragments that may be present). Sometimes this requires the removal of one or both of the bony outer plates (lamina) of the vertebra—a procedure known as laminectomy—in order for the surgeon to gain unobstructed access to the herniation site.
Success rates are fairly encouraging. If your diagnosis of sciatica due to herniated disc is made based on your personal history and physical and neurological exams alone, your chance of a positive outcome is about 60 percent. However, if your straight leg raise test is positive, good results increase to about 70 percent. If your diagnosis is backed up by all of the above, plus abnormal EMG/NCS results and positive imaging results, you can expect a 90 percent or better chance of improvement. Almost all people can return to work and normal activities within six to eight weeks of the surgery. Repeat surgery, when necessary, is typically not as effective as the initial surgery in terms of symptom relief and restoration of function.
In its 2009 practice guidelines on interventions for low back pain, the American Pain Society concludes that discectomy can be a good option for people who have radiating nerve pain caused by disc herniation. For the first few months, people who have the procedure are moderately better off than those who skip the surgery. The catch? The advantages of discectomy shrink or disappear after a year or two—so avoiding the procedure may be just as effective in the long run.
There are also several less-invasive surgical alternatives to standard discectomy/laminectomy:
Microdiscectomy: This procedure involves a significantly smaller incision through which a lighted tube (endoscope) is inserted, allowing the surgeon to view the herniation site. Then, using micro-instrumentation, the nerve-impinging portions of the disc can be cut away and removed through the scope. Sometimes traditional discectomy is preferable to microdiscectomy, as the former permits a better view of all the structures involved, which is useful in cases where disc fragments may be present that cannot be seen through the limited view of the endoscope. On the other hand, the smaller incision needed for microdiscectomy often means reduced tissue injury, and thus faster recuperation times, with less scarring. Given that success rates are comparable to those of standard discectomy, the American Pain Society says it’s unclear whether one approach is more effective than the other.
Percutaneous arthroscopic discectomy (PAD): This method is somewhat similar to microdiscectomy. A probe is inserted through a small incision. The surgeon uses fluoroscopy (continuous real-time X-ray imaging) to guide the probe to the surgical site. The probe is equipped with a cutting, irrigation and suction mechanism that is used to remove disc material, relieving pressure on the nerve root. One big advantage is that it requires only local anesthesia, and the person can usually go home the same or next day. PAD has even more limitations than microdiscectomy in terms of how much the surgeon can see.
Laser discectomy: With this procedure, the surgeon inserts a needle into the spine that delivers bursts of laser energy that vaporize the herniated portions of the disc. Pain relief may not be noticeable for several days, weeks or even months. Studies have yielded mixed reviews oflaser discectomy. In some cases, it appears no more effective than nonsurgical therapies; in others, it is about as effective as standard discectomy.
Intradiscal electrothermal therapy (IDET): Another less-invasive technique similar to the others, IDET involves the insertion of a wire that transmits heat into the affected region, destroying pain receptors at the site while strengthening the collagen fibers that keep the disc intact. Early studies of its effectiveness were encouraging; more recent studies, however, have generated less optimism and greater debate.