Back pain is one of the banes of humanity.
The cause, especially in the later decades of life, is usually cumulative degenerative changes in the lower spine involving the vertebral bodies, the discs between those bodies, the posterior joints and the associated ligaments.
Too often the result is chronic pain in the lower back, buttocks, hips and sometimes the legs (sciatica), as well as numbness and tingling in the legs.
Making matters worse for some patients, is that vertebrae sometimes slip forward on the vertebrae below (spondylolisthesis), further narrowing the spinal canal, and crowding and pinching nerve roots on their way through their exit routes (foramina) on the way to the legs.
Managing the related symptoms is especially challenging when the degenerative changes involve two or more levels because sorting out which levels are symptomatic, and which not, is problematic.
Degenerative changes involving the posterior joints, discs and ligaments may produce pain in addition to whatever pain might be related to the L3, L4, L5 or S1 roots or various combinations of those nerve roots.
That’s why it’s so hard for physicians and surgeons to figure out what's causing the pain and hence what might make a reasonable target for surgery. When we’re older – there are simply too many targets to reasonably explain the pain and too little evidence to differentiate among them.
None of this is made any easier by imaging studies such as CT or MRI because much beyond the age of 40, CT and MRI scans often show degenerative changes and disc “protrusions” in those with no symptoms.
Patients in their 30s and 40s are much easier to figure out because the cause usually involves a single level (L4-5 or L5-S1) and that level, based on the location of the tingling and numbness, usually matches the findings on imaging studies.
Would that be the case for those in their 70s and beyond. With them, there are simply too many targets to make sense of the probable precise source of the symptoms. Sometimes nerve blocks are used to “freeze” one or other potential site to see whether the symptoms improve. Unfortunately, the latter diagnostic findings are often misleading.
What we’ve ended up with is multilevel surgery and this usually involves taking most of the bony elements off the back of the lumbar spine and leaving the vertebrae in place (laminectomy). This theoretically, takes the pressure off the symptomatic roots by opening up the spinal canal and opening up the exit spaces for those nerve roots, while leaving the vertebrae and discs much as they were. Here there’s a division of opinion.
Many orthopedic surgeons, concerned about leaving an unstable spine behind after stripping it of most of its bony gage posteriorly, advocate putting a bony brace in place to fuse and provide some added rigidity to the spine after the laminectomy.
Most neurosurgeons, on the other hand, do not resort to fusion procedures. There’s no doubt that fusing the lower spine adds to the time required for the surgery and beyond that there’s the risk the fusion itself or the hardware used to hold them in place may break and cause additional symptoms.
In my experience, working with surgeons of both stripes in three different locations, I belong to the “no fusion” camp. That opinion recently received convincing support from two large studies, one in Sweden and the other in the United States, which argue that fusion is not needed in most instances. The accompanying editorial was solidly in the no fusion camp. That’s good news for most patients.
This, of course, doesn’t answer the question of whether surgery actually works in the later decades of life. Here the answer is a qualified yes. I say qualified because it’s one of those situations where picking the right surgeon is critical in making the right decision about surgery in the first place.
And should the decision be surgery, it’s very important the surgeon has the requisite skills and experience to get the job done with a high degree of confidence that the patient will be better.
That’s one of the reasons why several companies in the United States, such as Walmart, began to offer fully paid consultative, surgical and rehabilitation services at one of six top-notch U.S. medical centres. The goal was to improve the outcomes for employees who suffered from chronic lower back pain in an area of medicine filled with doubt and uncertainty.
That approach makes a lot of sense to me because Canadians should be offered similar care at those Canadian centres with the best track record for medically and surgically managing lower back pain.
Managing lower back pain for patients and physicians alike is challenging and in areas of medicine like this, where there’s a great deal of uncertainty, it makes sense to concentrate the assessment and management in a few centres of excellence.
That approach is offered for some medical and surgical special interests but needs to be expanded to the management of chronic lower back pain and especially surgery, but that’s a question for another column and another day.
To be discussed at the next Infohealth meeting on June 2 at 11 a.m. Register through the NOTL library. See you then.
Dr. William Brown is a professor of neurology at McMaster University and co-founder of the Infohealth series at the Niagara-on-the-Lake Public Library.