News Category: Lumbar Spine

Have you ever heard someone say they have to lose 50 or 100 pounds before the surgeon will perform a particular operation? But if you have ever watched the popular TV show Biggest Loser, then you know how much work it can be to shed those pounds.

Obesity isn’t just a lifestyle choice (though that is a big part). Fat storage and metabolism (breakdown) are highly complex body functions. Fat itself has recently been identified as an active endocrine (hormonal) substance. Survival mechanisms in the body make it much easier to store fat than to shed it.

Obesity is defined as a body mass index (BMI) of 30 or more. Keep in mind that obesity comes with a whole host of other problems that complicate surgery. Patients with a BMI of 30 or more are more likely to have problems with the anesthesia.

It will be more difficult to access veins for intravenous procedures. Positioning the obese patient, changing positions, and getting him or her up and moving after surgery to avoid blood clots are important tasks but can be very difficult.

According to the results of this study, putting off surgery may not be necessary with the newer minimally invasive spinal fusion procedures. Fifteen (15) patients with a BMI greater than 30 had the less invasive posterior lumbar interbody fusion (LI-PLIF). All of these individuals had tried a more conservative approach with rehab and exercise but failed to get improvement with their painful symptoms.

The LI-PLIF procedure is done from the back of the spine (posterior approach). The surgeon uses surgical tools that can be inserted into the spine without making a large incision. Minimally invasive procedures make it possible to spare the muscles and ligaments from being cut into, which is what happens during the more invasive open incision technique.

The surgeon removes the spinal (facet) joints on either side of the affected segment. This does two things: 1) turns off pain signals coming from the joint and 2) provides the surgeon (and patient) with bone for the fusion site. It’s a win-win situation for the patient.

The diseased disc is also removed. In its place, the surgeon inserts two metal mesh-like cages. Inside the cages are bone chips and bone dust from grinding up the bone removed from the joints. Additional bone will grow around the cage providing the strength and support of a pillar at that level.

By testing patients before and at regular intervals after the fusion procedure, the researchers were able to see changes in symptoms and progress in function. Other information collected and compared included length of time in surgery, amount of blood lost during the procedure, and number of days in the hospital.

Complications during (intraoperative) and after (postoperative) surgery were recorded for each patient. Less than 15 per cent had intraoperative complications. Only one-third of the group had any postoperative problems (e.g., poor wound healing, infection, continued pain). Most of those complications affected patients who were the most overweight (referred to as morbidly obese.

The main measure of interest was how many patients could return-to-work at their former job and previous (presurgical) level of function (or better). In other words, does obesity affect work outcomes after spinal fusion?

The results were very positive. With the less invasive posterior lumbar interbody fusion (LI-PLIF) procedure, there was less blood loss and therefore a shorter hospital stay. The less invasive technique was also credited with no blood transfusions, less pain, and faster return to full function. There were no blood clots or deaths among the 15 patients in this study.

The authors conclude that obesity (even morbid or extreme obesity) does not have to be an automatic “lose weight or no surgery” situation. Obese patients with chronic, unresponsive low back pain from degenerative disc disease can benefit from lumbar fusion.

The availability of newer, less invasive methods even makes it possible to get back to work within a year’s time of the surgery. One final note: none of the patients who were workers compensation patients returned to work. Further study is needed to select patients for this procedure who are not at risk for poor outcomes.

Ever wonder if that time you hurt your back will come back to haunt you? Disc degeneration is a common problem as we get older. Adding a back injury or trauma to the mix could speed up that degenerative process.

To find out if this might be so, researchers studied 37 pairs of twins (all men) who were part of an ongoing Twin Spine Study in Finland. They interviewed the men about past back problems and history of injuries on every job they had ever had. The same questions were asked regarding back injuries during any exercise, sporting, or leisure activity.

Normally, there are 157 pairs of (identical) twins in the Twin Spine Study. The only pairs included in this study were those who had one twin with a history of back injury (or injuries) and the other twin with no recall of any back problems.

The main measure of disc health was MRI study. The height of the disc and disc signal intensity on MRI were used to assess current disc status. Everyone in the study had an MRI of the lumbar spine (L1 to S1) done.

Various factors that might affect disc degeneration were considered. These variables included type of work (occupation) and load placed on the spine during labor, amount and type of exercise (sports or leisure), and any weight training the men had participated in over the years.

They did not find any significant differences in disc height or signal between the twins who had a previous back injury and the twin who didn’t. This was true for all 37 pairs. Twin members who lifted more weight at work were more likely to injure their backs but this did not seem to translate into faster or greater disc degeneration later.

Conducting a twin study like this with identical twins of the same sex and age helps control for these factors that might otherwise influence the results. By itself, this study doesn’t prove (or disprove) the theory that back injuries or trauma lead to disc degeneration. But it does add evidence to previous studies with similar results to suggest that back trauma or injury is not a risk factor for accelerated disc degeneration.

The authors do point out three important features of their study. First, the participants did not have X-rays showing specific tissue damage or pathologic changes in the spine due to their injuries. They based the history of back injury on patient recall.

Second, it is possible that twins who didn’t remember injuring their backs did, indeed, have a previous back injury. And third, time between injury and subsequent disc degeneration may be a factor. No one really knows how much time is required before measurable changes might be seen on an MRI. Only long-term studies will be able to answer that.

Scientists from The Netherlands have found three new factors that might help predict which patients with low back pain (LBP) will go on to develop chronic LBP. They describe chronic LBP as pain that lasts six months or more.

When it comes to low back pain, many researchers have attempted to find ways to predict who will get better and who won’t. It’s an important topic because so many people are affected by low back pain. The cost of treatment, lost wages, and lost productivity is in the billions of dollars worldwide.

If we could find ways to predict who might develop chronic low back pain, it might be possible to “head it off at the pass” so-to-speak. The areas studied over the years have been drilled down to four major categories: 1) demographics, 2) work, 3) clinical, and 4) psychosocial. In this study, they looked for the most common combination of factors rather than one single variable that might predict chronic low back pain most often.

Let’s take a brief look at each of these groups. Demographics refer to patient-specific factors: age, gender (male or female), level of education, marital status. Work as a potential prognostic factor has been examined in terms of job satisfaction, type of work (manual labor versus sedentary or inactive), job demands, and perceived control on-the-job.

Clinical factors refers to pain (and other symptoms), function, and disability. Pain was measured by intensity, frequency (how often it occurs, previous history of back pain), and duration (how long it lasted). Back pain that radiated down the leg was also counted as a possible important variable. Level of activity and restrictions at home, on-the-job, or during recreational and leisure events made up the function and disability categories.

And finally, the psychosocial category. There is a bit of overlap between this group and some of the others (e.g., marital status and family support, job satisfaction and stress, pain and pain coping, job demands and job control).

Kinesiophobia and fear avoidance behavior are two additional psychosocial variables considered as factors that may predict chronic low back pain. Both of these have been studied and reported on by other research groups.

Kinesiophobia refers to fear of movement or the fear that movement and/or exercise will cause a reinjury. Fear avoidance behaviors are the result of kinesiophobia — the person stops moving in ways that he or she thinks might cause pain.

This study was done at the VU University Medical Center in Amsterdam, The Netherlands. The research team included physicians, physical therapists, faculty, and staff from the Institute for Health and Care Research, Department of Methodology and Applied Biostatistics, Institute for Health Sciences, and the Department of Clinical Epidemiology.

They didn’t study patients directly themselves. Instead, they took the results from three high-quality studies (randomized controlled trials) and merged the data. This type of study design makes it possible to compare the effectiveness of different treatment types while looking for predictive or prognostic factors.

All three studies included workers from The Netherlands. There were airline company workers, luggage handlers, heavy steel construction workers, office workers, and health care workers. The majority of people tended to be on the manual labor or heavy duty side of things. The trials compared usual care with graded activity, ergonomic intervention with graded activity, and low to high-intensity back schools.

Data was collected through a wide range of questionnaires completed by the study participants. There were surveys for everything from pain to activity (sports, work, leisure), job requirements (lifting, bending, twisting), coping strategies, job satisfaction, fear avoidance, and kinesiophobia.

Some of the tools used included Numerical Rating Scale (NRS), Baecke Questionnaire, Roland Disability Questionnaire, Dutch Musculoskeletal Questionnaire, Job Content Questionnaire, Tampa Scale for Kinesiophobia, and Fear Avoidance Beliefs Questionnaire. So you can see each potential variable (possible predictive factor) was tested for and given a quantitative (number) score.

With all that digging for information and analyzing the combined data from three studies, what did they find? Their final prognostic model contained three factors: 1) no change in pain intensity and disability during the first three months of low back pain, 2) high pain intensity at baseline, and 3) the presence of kinesiophobia right from the start.

It makes sense that severe back pain that doesn’t get better right away is likely to result in chronic (long-term) symptoms. And this factor was no surprise as other studies have found the same thing. Other studies have also reported kinesiophobia as a critical factor in predicting chronic low back pain. This is the first study to find all three combined together as a predictive model.

One thing they did NOT find was that age, gender, pain coping, the presence of back and leg pain, disability status, or fear avoidance had any effect on prognosis. Other studies have reported these variables as possible predictive factors. There are many reasons why this might be so but future studies are needed to investigate this further.

You may be wondering: what about the different ways patients were treated (usual care, ergonomic changes, graded activity)? Well, it turned out that treatment results didn’t have much influence on the development of chronic pain, so that piece was dropped from consideration in the final analysis.

In summary, among both blue- and white-collar workers, change in pain intensity and disability status in the first three months of low back pain can be used to gauge prognosis. In particular, these variables can be used to predict who will go on to develop chronic low back pain (lasting six months or more).

Based on this information, physicians treating patients with new onset of acute low back pain are advised to keep close tabs on them. Seeing these folks more often during the initial episode of low back pain might help reduce the number of patients who progress to become chronic pain patients.

At the same time, more studies are needed to identify specific treatments that work for each patient category. Patients with acute low back pain for the first time should be tested for kinesiophobia. The presence of fear of movement early on should be addressed immediately to help keep acute low back pain from developing into chronic pain.

For a very long time, spinal fusion was the answer to chronic low back pain. But with time, surgeons were also able to see that once the spine was fused, load transferred to the next segment caused degeneration there as well. They call this phenomenon: adjacent segment degeneration (ASD). Many solutions to the problem of ASD have been proposed.

The use of artificial disc replacement has been one way to approach the problem. The hope is to preserve spinal motion while protecting the adjacent vertebral levels. But when comparing the results between spinal fusion and disc replacement, there hasn’t been an overwhelming benefit shown for disc replacement over spinal fusion.

For that reason, some surgeons continue to look for ways to improve results of spinal fusion. They have tried different fusion techniques. They have analyzed patient factors looking for ways to identify patients who would benefit the most from spinal fusion.

In this study from Denmark, surgeons looked at the rate and extent of adjacent segment degeneration after lumbar spinal fusion for two different groups. Group one had a lumbar fusion at one level using the posterolateral approach.

Posterolateral means the surgeon fused the two segments together by coming into the area from the back and slightly off to the side. The results of posterolateral fusion (PLF) were compared to the second group who had a PLF combined with an anterior lumbar interbody fusion (ALIF).

In the ALIF procedure, the surgeon works on the spine from the front (anterior) and removes a spinal disc in the lumbar spine. The surgeon inserts a bone graft into the space between the two vertebrae where the disc was removed (the interbody space).

Previous studies have already shown that PLF + ALIF yields better results compared with PLF alone. In this study, they took a closer look at the results trying to find out why anterior column support provided by the ALIF makes a difference.

They used MRIs to examine the discs looking for any signs of degeneration, herniation, stenosis (narrowing of the spinal canal), and endplate changes. Stenosis occurs when a herniated disc pushes into the spinal canal reducing the space available for the spinal cord. The endplate is a circular-shaped piece of cartilage located between the disc and the vertebral bone.

With disc degeneration, the endplate can get damaged as well. Sometimes with the loss of cushioning (normally provided by an intact disc), the increased pressure between the two vertebral bones exerts enough force to push the endplate up into the bone. Imaging studies detect these kinds of changes.

Patient characteristics were also collected as data and analyzed for possible factors affecting degeneration of the segments adjacent. Maybe developing adjacent segment degeneration (ASD) after lumbar fusion is really a matter of how old you are when you have the surgery. Or perhaps lifestyle choices are the key (smoking, exercising, obesity) to unlocking why ASD develops in the first place.

Everyone in the study was treated at the same spinal center. They were all between the ages of 20 and 65 years old. They were randomly selected to be in either group one or group two. There were an equal number of patients (73) in each group.

In addition to X-rays and MRIs as outcome measures, the patients filled out a number of different questionnaires designed to provide information on mental and physical health as well as before and after measures of symptoms, function, patient satisfaction, and quality of life.

They found that almost everyone in both groups had some evidence of adjacent segment degeneration (ASD). And two-thirds of those patients had signs of ASD at more than one level. Disc degeneration and disc herniation were the most common signs of ASD.

Endplate changes were seen in one-fourth of the total group (group one and group two). Endplate changes were most likely to occur at the first adjacent level and were always linked with disc degeneration. That makes sense since endplate changes seem to be a late event in the degeneration process. They are rarely seen without associated disc disease. And endplate changes at the first adjacent level were always more severe than changes seen two or three levels away from the fusion site.

For patients who did not have any changes in disc height over time, it became apparent that age was a factor. It was always the younger patients whose disc spaces remained intact and older adults who had obvious signs of disc narrowing.

What was the take-home message from this study? First, adjacent segment disease (ASD) is common after spinal fusion. But this phenomenon is not yet directly linked to the fusion procedure. It’s possible that these same patients would have experienced just as much ASD if they had not had the surgery.

Second, anterior fusion does increase support to the spinal column and results in better overall outcomes. The exact factors that contribute to these improved results remain unknown. And third, (older) age is a definite risk factor for ASD.

In summary, surgeons are trying to find ways to improve patient outcomes following spinal fusion. Taking into account patient risk factors and surgical techniques, this study was still unable to explain the superior results in patients who have lumbar spinal fusion using a combined PLF + ALIF approach.

For the moment, it does not look like ASD is accelerated by spinal fusion — it would have happened anyway. Surgeons will continue to study this problem looking for clear explanations and solutions to the problem of ASD.

The role of Schmorl’s nodes in disc degeneration is the topic of this study from Southern China. To understand Schmorl’s nodes, picture two vertebral (spinal) bones with a disc between them. Now imagine a circular layer of cartilage between the disc and each vertebra. That bit of cartilage is called the end plate. Schmorl’s nodes occur when the disc pushes through the endplate and into the next vertebra. On imaging studies these look like small hollowed areas.

Schmorl’s nodes can be seen on X-rays and are often present in patients diagnosed with disc herniation. Is this a coincidence or does it have some particular meaning? Do Schmorl’s nodes occur without disc degeneration? If a person does have Schmorl’s nodes, does that mean the disc is going to degenerate? And final question, just what does the presence of these nodes signify?

There are some theories about why Schmorl’s nodes develop. In many cases, we just don’t know why they show up. They seem to develop without cause. That’s referred to as idiopathic. Sometimes, there is a clear cause such as a tumor, decreased bone mineral density, or trauma. In order to understand the etiology (cause) of Schmorl’s nodes better, the authors of this report examined the lumbar spine of 2,449 (adult) volunteers using MRIs.

The participants in the study were everyday people from the general population. Some had low back pain but the majority had no history of back pain or problems. Anyone with a history of back surgery, spinal tumors or infection, or any diseases of the spine was not allowed to join the study.

After all the MRIs were read and interpreted, participants were divided into two groups: 1) those who had no evidence of Schmorl’s nodes and 2) anyone with clear evidence of one or more Schmorl’s nodes. As with most research, the patients’ ages, activity level and sports participation, height and weight (also known as body mass index or BMI), and use of tobacco was recorded.

For both groups, the radiologists also looked at the condition of the disc, disc height, and any other signs of disc degeneration (tears, fissures, disc narrowing). Then they compared the two groups to look for any clues that might explain the role or function of Schmorl’s nodes. They found that in the general population, slightly more than 80 per cent did not have any Schmorl’s nodes. For the nearly 20 per cent who did have evidence of this anatomic feature, more than half had multiple levels affected.

The upper lumbar spine (especially L23) was the most common site for Schmorl’s nodes to be seen. Age wasn’t a significant factor except that older adults were more likely to develop disc degeneration. And it was those participants with disc degeneration who had the most Schmorl’s nodes. In fact, the more severe the degeneration, the more likely they were to have Schmorl’s nodes. Body mass index was also much higher in the group with Schmorl’s nodes. This seems to suggest that being overweight or obese puts older adults at increased risk for Schmorl’s nodes as a complication of disc degeneration.

Perhaps the most surprising finding was that disc bulging wasn’t linked with Schmorl’s nodes as clearly as disc narrowing. In fact, the people with disc bulging were less likely to have node development. One possible explanation for this is the fact that disc narrowing puts more pressure on the disc, forcing the disc material into the endplate. The most severe cases of disc degeneration also had the greatest disc narrowing.

Because this study was done in Southern China, the authors compared their results with other studies reporting on the prevalence of Schmorl’s nodes in other ethnic groups (e.g., European-Americans, African Americans. The percentage of Chinese affected was much less than these two other groups. What factors might account for the low rate of Schmorl’s nodes in this group of Southern Chinese adults? The results of this study don’t answer that question directly. The authors review other research results and suggest factors such as genetic influences, differences in posture and subesquent load on the spine, and perhaps ethnic differences in the size and strength of the endplates. In all groups, men with a higher body weight (and therefore greater upper body load placed on the endplates) had a greater risk of endplate failure and the development of Schmorl’s nodes.

The authors conclude that taking all the information gathered from human studies (cadavers), animal studies, and comparison studies like this one with live humans, it seems reasonable to think that damage to the endplate can lead to disc degeneration. It’s likely that there are multiple factors involved and not just one reason why Schmorl’s nodes develop. Genetics, nutrition, body mass index, and severity of disc degeneration may all work together to result in end-plate changes leading to Schmorl’s nodes.

Which sounds worse: you have disc degeneration or you have some wear and tear on the discs? What about this: your MRI shows some signal loss at the L4-L5 disc level versus there is a narrowing of the disc space at L4-L5?

Medical terms used to explain diagnostic results of tests and imaging studies can have a profound effect on how a patient perceives his or her potential for healing. Focusing on repair and healing of disc problems rather than discussing ongoing damage may be a more helpful and positive approach in managing low back pain.

Labels and beliefs about those words are something health care workers may need to re-evaluate. As the results of this study show, messages regarding low back pain and how patients perceive the words health care professionals use have an important effect on their prognosis.

For example, when told that the cause of their low back pain was disc degeneration, some people interpreted that to means their spine was crumbling or collapsing. Use of the term wear and tear by the physician was used later by the patient to say that everything was wearing out.

The problem isn’t just with the patients’ interpretation of what they are told (or more accurately, what they “hear” from what they are told). Health care providers have their own beliefs about patients they treat and may unintentionally convey the wrong message.

There is even evidence that some of these beliefs are not consistent with current recommended guidelines for the care and management of chronic problems like low back pain. Patients are often strongly influenced by what their physicians, surgeons, therapists, and nurses tell them about their condition.

Medical reports from radiologists reading and interpreting imaging studies contain words like degeneration, which may have nothing to do with the patient’s symptoms. There have been plenty of studies that show the severity of changes observed on X-rays often have no correlation to patient symptoms.

For instance, it has been observed that some people with what looks like severe degeneration of the spine have no symptoms whatsoever. At the same time, there are others who report excruciating pain with nothing seen on X-rays to indicate a problem.

In this particular study, patients with chronic low back pain were asked, What do you think is going to happen in the future? There were a wide range of responses indicating both hopes and beliefs. Patients used words like cure, permanent disability, crippled, and not going to get better to describe their expectations.

They gave explanations for their pain including getting old, overdoing it, and the back is going. By comparing what the radiologists’ reports said with what the patients’ were told by their physician or surgeon, it was possible to see that some of the patients’ beliefs were from their own interpretation of what they were told.

What are the implications of these results for physicians, surgeons, and other health care professionals? The authors suggest that health care providers interpreting test results for patients need to take a closer look at their word choices.

It might be important for radiologists to use terms and language more carefully knowing that others may be speaking for them to the patients. Using words that focus on mechanical or degenerative aspects of the spine appear to give patients the perception that their prognosis is worse than it actually is. Using words that focus on healing, repair, and recovery rather than focusing on degenerative aspects of the spine may actually foster a better outcome in the long-run.

Pain is a subjective sensation. It can’t be seen, photographed, or shown to someone in three-dimensions (3-D). That can create a dilemma when trying to measure this symptom to show improvement with treatment.

In the research world, studying low back pain and finding effective ways to treat it has become an international effort. Therefore, it’s important that the main measure of results (reduced pain or pain relief) is reported the same from study to study. Consistent reporting of results makes it possible to compare study results and even combine the results of several studies to create a systematic review of the topic.

There are many different ways to measure pain. The simplest is asking a scale from zero (no pain) to 10 (worst pain) and ask the patient to give an objective (measurable) number to their subjective pain. This type of scale is called a numerical rating scale (NRS) or verbal rating scale (VRS).

Another example of a verbal rating scale is the Likert-type scale. In this type of scale, the patient pinpoints the pain intensity or severity using word descriptors such as no pain, mild pain, moderate pain, severe pain, or very severe pain. Each of these pain categories is divided into five separate levels of pain with equal distance between each pain item on the scale.

Another type of pain rating scale is the Visual Analog Scale (VAS). The VAS is made up of a straight line drawn on paper. The line can be drawn up and down (vertical) for patients who can’t sit up or straight across (horizontal) for those who can be seated. In either case, the line is always 100 mm long (about four inches).

For a horizontal line (straight across), the left end represents “no pain” and the right end represents “pain as bad as it could possibly be” or “worst possible pain.” When the line is presented in a vertical orientation (up and down) for the client who is lying in bed and cannot sit up for the assessment, “no pain” is placed at the bottom and “worst pain” is put at the top.

Any of these rating scales can be used to assess current pain, worst pain in the preceding 24 hours, least pain in the past 24 hours, or any combination the clinician finds useful. Both the Visual Analog Scale (VAS) and the Five-Item Verbal Rating Scale have been tested and shown to be reliable and valid. In other words, each time the VAS or the VRS scale is used by itself, it really does measure pain in the same way from patient to patient and from one time period to another for each individual patient.

That brings us to explain the purpose of this study. Many health care professionals use these two tests interchangeably as if they measure exactly the same thing. We know from other studies that the two tests are highly correlated. That means if someone has a high (or low) pain score on one test, they will also have a high (or low) score when given the other test.

But is the data collected from one test really the same as the other — so that results from studies reporting one or the other can be considered equal? Do these two tests measure the same aspects of low back pain exactly alike? According to the authors of this study, no, they do not. Let’s take a closer look at how they came to this conclusion.

One hundred and fifty-one (151) patients with lumbar degenerative disease participated in the study. They completed both scales before and after spine surgery. They used the scales to answer the question, How severe was your back pain in the last week? They also completed a number of other questionnaires to assess pain, function, and work status.

Using biostatistical analysis, the researchers were able to see that comparing the results obtained with one scale to the other did not yield equal results. For those readers who understand statistical analysis, you will be interested to know they came to this conclusion using a measure of disorder and level of concordance.

Basically, what this means is that using five-items on the Verbal Rating Scale (none to very severe) isn’t the same as marking the 100 mm Visual Analog Scale (VAS) into five equidistant values.

In other words, a VAS between zero and three doesn’t really mean the patient’s pain level is “mild” as measured by the same distance on the Verbal Rating Scale. A VAS between three and six doesn’t correlate to “moderate pain” on the VRS. And more than seven (severe pain) on the VAS doesn’t match up with the higher categories of the VRS.

There is too much overlap of scores from one tool to the other to use them interchangeably as if they are measuring exactly the same pain levels. Once again, results like this point out the difficulty of measuring perceived pain. Some tools may make it easier to over- or under estimate severity of pain.

In summary, when using back pain as a measure of results of treatment, scientists around the world need a standardized outcome measure. Such a standard measuring tool would allow researchers to make international comparisons. The Visual Analog Scale (VAS) and the Verbal Rating Scale (VRS) may be used together but they cannot be used interchangeably as if what they measure is the same.

The authors offer one final note about their study. They point out that these results really only apply to people in a hospital setting undergoing spine surgery for severe low back pain associated with degenerative lumbar disease. The same results may be seen with patients in other settings like a primary care clinic or rehab unit and with patients who have less intense pain. But that conclusion isn’t to be assumed without specifically studying those different parameters.

Looking for some relief from that back pain caused by spinal stenosis but don’t want the roto-rooter surgery? Here’s some good news: there is an alternative treatment available. As this study shows, the use of the X-stop spacer can achieve the desired relief from pain without decompression surgery.

To help you understand what this is all about, let’s explain a few terms. First, spinal stenosis is a narrowing of the spinal canal. The spinal canal is the channel or opening created by the vertebral bones stacked on top of each other. Inside the canal is the spinal cord as it travels from the brain down to the lumbar spine.

Degenerative changes associated with aging such as bone spurs, thinning or bulging of the discs, collapse of the vertebral bodies, and stiffening or infolding of the spinal ligaments all reduce the space inside the canal. Since the spinal cord doesn’t shrink with age, the net result of stenosis is pressure on the spinal cord and/or the spinal nerve roots.

Decompression (sometimes referred to as “roto-rooter” surgery) involves scraping away the excess bone and restoring space within the canal. Sometimes the surgeon performs a laminectomy (removes a portion of the bone from around the spinal cord). But decompression doesn’t improve the disc space or realign the compressed vertebrae.

That’s where the X-stop comes in. This device is implanted between the spinous processes of two vertebrae. The spinous process is the bony knob you feel along your backbone. It is a projection of bone off the back of each vertebra that provides a place for ligaments and muscles to attach.

By slipping the X-stop between the spinous processes, it’s a little like using a jack to lift your car off the ground. It separates the vertebrae and puts them in a slight bit of flexion — just enough to take pressure off the spinal cord, spinal joints, and spinal nerve roots. It’s a fairly new treatment technique so research is ongoing to evaluate its effectiveness.

In this study from Scotland, orthopedic surgeons used a positional or stand-up MRI to measure the increase in space around the spinal cord. A positional MRI takes pictures of the disc height, spinal canal area, and space around the spinal nerve roots with the patient sitting, lying down, and standing up (weight-bearing). The effects of the X-stop on lumbar spine movement were also measured using positional MRIs.

The X-stop isn’t used routinely with patients who have painful spinal stenosis. Usually, physicians prescribe antiinflammatories, physical therapy, and/or steroid injections first. But if these conservative forms of treatment don’t help, then surgery is considered.

There were 48 patients (men and women) who met that criteria and were included in this study. Some patients (29 of the 48) received a single-level X-stop while others (19 or the 48) had double-level procedures.

Positional MRIs were taken before X-stop implantation and again two years after surgery. Patients also filled out a survey designed to assess change in pain and patient satisfaction.

Results were variable among the 39 patients still in the study after two years. There was no improvement (or only minor changes) in pain and function for one-fourth of the group. While most of the patients had an increase in the canal space, there was no change for eight of the patients.

And although the space inside the spinal canal was increased, there was no change in the foraminal space (hole through which the nerve roots pass). Lumbar motion was also unchanged from before to after X-stop implantation.

The authors conclude that the X-stop is a safe but not always effective alternative to decompression surgery. Patients with severe stenosis are less likely to get relief from pain with this treatment.

It is recommended that positional MRI be used to pre-select patients who can benefit the most from X-stop implantation. Those patients who experience pain relief while sitting or when the spine is flexed (bent) seem to have the best results.

Spinal cord stimulation (SCS) is used for 1000s of people with chronic, debilitating pain but how it works is still a mystery. Scientists from France conducted a study with 20 pain patients to help unravel the mechanisms behind pain relief with this treatment.

A spinal cord stimulator, also called a dorsal column stimulator, is an implanted electronic device used to help treat chronic pain. They have been used for over 30 years. The device delivers a low level electrical current through wires. The wires are placed in the area near the spinal cord. The device is similar in size to a pacemaker.

The original theory behind how these devices work is called the gate control theory of pain. According to this theory, electrical stimulation generated by the stimulator replaces the pain impulses.

The gate theory suggests that when the electrical stimulation reaches the spinal cord first, the “gate” closes and blocks the pain impulses. As pain lessens, the muscles around the sore area relax, further lessening pain. But studies over the years have shown that this theory only explains some of the pain relief obtained. It probably isn’t the only way the stimulator works.

That’s where this study comes in. They used the spinal cord stimulator for patients with chronic leg pain after failed back surgery. The experiment was set up so that electrical stimulation was placed ON for one hour and then OFF for one hour.

During those two hours, a set of data was collected including plantar sympathetic skin response (SSR), F-wave, and somatosensory-evoked potentials (P40-SEP) from the tibial nerve. Another group of measurements were taken from the sural nerve including H-reflex of the soleus muscle and nociceptive flexion (RIII) reflex.

Unless you are an expert in electrophysiology, these terms won’t mean anything to you. The basic idea is that they are testing nerve transmissions for pain to two nerves in the lower leg (the tibial and sural nerves).

By looking at all the various ways pain can be transmitted, when the patient had pain, and when the pain was gone, they were able to find the pathways pain travel and understand how to turn them off.

It might be helpful to understand who was in this study. As mentioned, all 20 participants had chronic burning or freezing lower leg pain from failed back surgery. Other symptoms included electric shock sensations, pins and needle sensation, tingling or itching, numbness, or increased pain brought on by rubbing the painful area.

Surgeries included disc removal (discectomy), spinal fusion, opening the space around the spinal nerves (foraminotomy), and removing some of the bone from around the spinal cord (laminectomy). All of these procedures are designed to reduce pressure on the nerve tissue (spinal cord or spinal nerve roots).

The group included men and women between the ages of 36 and 66. They all had used a spinal cord stimulator for more than a year with good results. Knowing the unit worked for these patients, the researchers used this experimental design to test different neural pathways. The goal was to find out what was affected (and what wasn’t) in bringing about pain relief.

The authors provide a detailed description of each of the neurophysiologic test procedures performed. They also offer analysis of the statistical methods used to make sense of all the data collected.

The important finding from this study was that spinal cord stimulation actually affects not one, but several different neural pathways. By testing different nerve pathways, they found which ones were inhibited or “turned off” to produce pain relief.

The results from this study confirm that spinal cord stimulation can be very helpful for people with chronic leg pain that is caused by changes in normal nerve function. It’s likely that patients with just leg pain will benefit more than patients with back and leg pain, especially when the back pain is mechanical in nature, not neurologic.

They can also use this information to test patients who have chronic pain from other neurologic problems. The use of spinal cord stimulation may expand to include patients with nerve pain as well as motor disturbances.

What happens to people who have chronic low back pain but don’t go see a doctor or get medical treatment? Does it eventually go away on its own? This may be the first study ever to report on the natural history of untreated low back pain. The information comes from Switzerland where large population-based studies are popular.

Large numbers of people participate in group studies of this type. They fill out diaries with information of interest to the researchers. They have regular follow-up assessments.

This particular study was designed to observe the musculoskeletal health of over 16,000 people. Four hundred of those individuals reported having low back pain. The information they provided was used to analyze them as a subgroup.

None of these people with low back pain went to their physician or got any medical treatment for the problem. That was their decision — it wasn’t a requirement of the study. But they agreed to be part of the study and fill out some additional diaries and surveys week-by-week for a full calendar year.

They answered questions about their work, daily life, and participation in sports or recreational activities. They documented their pain level, medication use, and work or social limitations caused by the back pain.

After analyzing all the data collected, the 400 participants appeared to fall into one of four groups. These four clusters included people with: 1) severe persistent pain, 2) moderate persistent pain, 3) fluctuating pain, and 4) mild persistent pain.

Most of the people were in groups 2 and 3 (moderate or fluctuating pain). About 10 per cent were in the severe group. This may be the smallest group because people with severe low back pain usually seek help. The last 20 per cent were in the mild persistent category.

The groups were very even (similar) in terms of weight, activity level, education, location (urban or rural residence), and general health. The biggest difference noted was age — younger people had more mild pain, whereas older folks were more likely to report severe pain.

By looking at what the participants in all four groups wrote in their diaries, the researchers were able to see that after a year, most people had less pain but no one was in a recovered group. There was some cross-over from group to group.

Cross-over refers to people who started out in one group and ended up in another. Cross-over occurs when anyone changed from one group to another based on frequency, intensity, and duration of painful symptoms. So for example, someone with mild pain ended up in the severe pain group or people with moderate pain improved enough to fall into the mild group.

Individuals in the moderate persistent group were the least likely to cross-over into a different group. The authors suggested they remained in the moderate persistent category because they did not seek medical help or treatment. Perhaps if their back pain got worse and became more severe, they would have gone to their doctors. People in the fluctuating group were the most likely to change groups.

The authors conclude this is the first large study of its kind. From the results of this study, it looks like the natural course of chronic and recurrent (untreated) low back pain is one of shifting patterns.

Patients move in and out of different phases of low back pain. Untreated low back pain tends to fall into one of the four pain patterns described. And although there is cross-over, most people still had back pain a year later.

The problem of low back pain continues to be the topic of many research efforts. Studies so far have shown that psychosocial factors (e.g., work status, mental health, level of education, blaming work for pain) are linked with pain, disability, and failure to return-to-work.

But are there other, more clinical risk factors for ongoing (chronic) low back pain and/or disability? This large study from Denmark suggests there are indeed other factors to consider.

Some of the predictive risk factors still fall under the heading of psychosocial such as worrying about health and worry in general. Others are lifestyle choices that can be modified including drinking less than one drink per month and a lack of regular exercise.

The year-long study included 325 men and women who were off work for at least three weeks (and up to 16 weeks) with either just back pain or back and leg pain. Leg pain signifies nerve irritation called radiculopathy. The underlying cause of the pain was disc degeneration (confirmed by X-rays and MRI).

The authors were particularly interested in breaking down the results to look at the link between disability and pain after one year, just disability at one year, change in disability during the same year-long follow-up, and change in back and leg pain. They also looked at how many patients were able to go back to work and percentages for each group (back pain only, back and leg pain).

Almost 40 different variables were examined looking for an association between each one and the outcomes (main outcomes being disability, intensity of pain, return-to-work). They decided not to limit the outcomes based on pain because many people press on and function normally despite their pain. So although pain contributes to disability, it isn’t always a good measure of disability. Function during daily and work activities is a better gauge of ability/disability.

Some of the factors investigated included age, body mass index, presence of tender points, intensity and duration of pain, use of pain medication, compensation claim pending, marital status, any children, type of job, personal/family income, and level of education or vocational training. Use of tobacco, alcohol, and physical activity and exercise were also measured. Worry, mental distress, depression, and anxiety were included in the comparisons.

At the end of one year, two-thirds of the patients had returned to work while almost 20 per cent were still off work on sick-leave. The rest were either training for another job, working part-time, retired, or going back to school. For those who did go back to work, there was an equal number treated for their low back pain with a multidisciplinary approach versus a short intervention program.

As suspected, a change in disability (not a change in pain) was a greater predictor of return-to-work status. Those who were able to go back to work reported less overall pain and tested at a higher functional level than those who remained on sick-leave. Tender points throughout the body and lack of leisure activity or exercise were common in patients who still had pain and disability a year after treatment. Higher level of disability and lower change in disability were observed in patients with a Worker’s Compensation claim.

What do the results of this study suggest? First, exercise remains a top priority for getting people with chronic low back pain back to work. For those who remain on sick-leave, there is evidence that a traditional physical therapy program is not as effective as graded activity. With graded activity, improving function (not reducing pain) is the focus. Exercises are geared around function at home and at work.

Worry and anxiety seems to play a key role in patients’ perceptions (how they view themselves). Behavioral or cognitive therapy might be helpful. Being older and overweight were two factors present in patients who did not return-to-work at all.

Older adults and those who don’t drink were also more likely to experience continued disability a year after treatment for low back pain. Does that mean workers still on sick-leave for low back pain after a year should drink more?

Probably not. It’s more likely an indication that their level of stress and mental distress is higher than in patients who drink more. The authors suggest that there may be a biologic explanation for this difference. Either way, more study is needed to understand the association between alcohol, disability, and return-to-work before specific recommendations are made.

In summary, the results of this study confirmed what is already known about psychosocial factors being linked with chronic low back pain, disability, and failure to return-to-work (i.e., remaining on sick-leave). Some additional risk factors were added to the list: lack of exercise, diffuse tender points at the start of the treatment, older age, and drinking less than once a month.

The sacroiliac joint (SIJ) formed by the sacrum wedged between the spine and the hip is the subject of ongoing controversy and debate. Some experts refuse to believe the sacroiliac joint is a true synovial joint that moves. They base this opinion on the fact that there is very little sacroiliac motion that can be detected or directly measured.

But most agree that not only does the sacroiliac joint move, it can generate pain that is felt in the low back or buttock area. Studies to that effect report between 14 and 40 per cent of all cases of back pain are really caused by a problem in the sacroiliac joint.

Like all synovial joints, the sacroiliac joint can be subjected to change over time. Along with aging comes osteoarthritis of the SI joint. Other causes of sacroiliac-induced pain include the presence of other low-back problems, spinal fusion surgery, pregnancy, infection, or tumors.

Diagnosis of problems affecting the sacroiliac joint can be extrememly difficult. The current tools we have include the patient interview, physical examination, and imaging tests. During the exam, the physician tests motion, carries out palpation and provocative tests, and then orders appropriate imaging tests.

But these screening tests are very limited in what they can find so imaging studies (e.g., X-rays, CT, MRI) are often needed. Bone scanning can be done when the surgeon suspects tumors, inflammatory lesions, and other abnormalities. A newer scanning technique called the fire scan combines CT, SPECT,and bone scan technology to create a colorful image but studies have not been done yet to support this as a valid and reliable diagnostic tool.

Once the diagnosis has been made, it is often still considered a provisional diagnosis. This is more of a wait-and-see kind of diagnosis. If it gets better with treatment for the suspected cause, then it is assumed the correct diagnosis was made. For example, steroid injection into the sacroiliac joint (SIJ) that reduces or eliminates painful symptoms confirms the problem was coming from the SIJ.

Other conservative (nonoperative) care can include manual therapy provided by an osteopathic physician, chiropractor, or physical therapist. The use of muscle energy techniques, strain-counterstrain, and mobilization or manipulation of the joint are often used by these professionals.

When the sacroiliac joint is extremely painful and unstable despite conservative care, then surgery may be an option. The most common surgical procedures performed on the sacroiliac joint include cutting the nerve(s) to the joint and fusion of the joint (referred to as arthrodesis). But even with the surgical approach, there isn’t enough evidence to point to one way to approach this problem over another.

In summary, the author of this article provides a review on the diagnosis and treatment of sacroiliac joint pain. He points out that there is no reference standard for making a clear or definite diagnosis of sacroiliac joint problems. Even with imaging studies and diagnostic injections, sacroiliac pathology can be hard to detect. Results of these test measures are often variable and unreliable.

In the end, the surgeon must take each patient on a case-by-case basis and conduct the examination one step at a time. Each diagnostic tool provides some information. The examiner must not lose sight of the big picture (the whole patient) when one finding is positive over another. Taken together, all the individual findings may eventually point to the sacroiliac joint as the cause of the painful symptoms.

Everyone believes that lifting heavy objects or even lifting light to moderately heavy objects when done repeatedly can cause low back pain. But does it really? Or is it more a matter that the back pain would have happened anyway and it was just noticed for the first time while lifting?

These are the questions posed by a group of epidemiologists from seven different medical research institutions in Canada. Epidemiologists are researchers who collect data over time and look for trends. In this study, they reviewed studies already published in what is called a systematic review.

By systematically searching various medical libraries, health journals, and even unpublished reports they were able to come up with 2,766 different studies related to these questions. They used specific search terms such as low back pain, occupational setting, work place, and lifting to find what they were looking for.

Thirty-five (35) studies met the criteria they had set up before starting the search. As the search terms suggest, that criteria included studies written in English or French related to low back pain, occupational lifting, and cause of low back pain. Each study had to have at least 30 subjects for the findings to be statistically significant.

There were many details reviewed from these studies: types of lifting, amount of weight lifted, severity of back pain, and whether or not sick leave was used. There was a broad range of specific occupations studied (e.g., nursing, retail salespersons, heavy manual laborers, administrators). The studies were conducted in 16 different countries including the U.S., Sweden, Russia, South Africa, Denmark, China, Turkey, Canada, The Netherlands, Nigeria, the United Kingdom, and India.

When all the data was analyzed, there simply wasn’t enough evidence to show a direct causal relationship between occupational lifting and the development of low back pain. There was one study that suggested regularly lifting more than 25 kg (70 pounds) was associated with low back pain. But unless this finding is found in other studies, it’s not enough to say for sure one (lifting) is the cause of the other (back pain).

The authors of this systematic review also point out that one of the major problems in conducting a review of this type is the poor quality of studies being reviewed. They don’t all use the same outcome measures. So it’s difficult to pool the data and make any sense out of it.

Different studies look at different factors but it’s difficult to analyze all the various possible reasons why workers experience back pain while lifting. Besides the obvious (lifting a heavy object), there may be twisting, bending, or awkward postures involved. Age and gender (male versus female) could be possible factors.

And what about the size of the object, whether the object was being picked up or lifted overhead, use of handles and the distance the object was carried after lifting. What about factors like which shift the worker was on when the injury occurred (day, evenings, nights) or when during the shift the pain started (early, mid, late)?

You might wonder why it’s even necessary to conduct studies like this one. Common sense tells us that heavy lifting can result in low back pain. But from an epidemiologist’s point-of-view, cause and effect with these two things (lifting and back pain) must be proven not just suspected. It could be coincidental that lifting precedes back pain. Or there could be a group of factors that must occur all at the same time to result in low back pain.

And public policy regarding work guidelines come from studies like this one. Clearly, low back pain in the working population accounts for a large portion of sick leave, lost wages, lost productivity, and high medical costs. Public health officials have a duty and responsibility to make decisions based on an accurate understanding of risk and result.

Right now, spine physicians simply can’t prove (or disprove) that low back pain is caused by work-related lifting activities. Future studies must continue to look for directly linked risk factors for low back pain that develops on-the-job. The goal to prevent these episodes cannot be achieved by putting into place strategies that are based on beliefs or even on what seems logical. Evidence to support public health guidelines is a must.

Aging Baby Boomers (those born between 1946 and 1964) are now being referred to as the age wave or gray tsunami. With an expected 64 million adults turning 65 over the next few years, health care costs are expected to soar. Based on current statistics for older adults, surgeons expect to see a significant rise in Medicare dollars spent on lumbar spine surgery.

One area of particular interest is centered around the diagnosis of lumbar spinal stenosis. Spinal stenosis is defined as a narrowing of the spinal canal where the spinal cord travels down the spine. The effects of aging (e.g., bone spur formation, thickening of spinal ligaments inside the canal, disc degeneration) shrink the amount of space for the spinal cord.

Spinal nerve roots that leave the spinal cord can also be affected. The resulting pressure or irritation of nerve tissue can cause low back pain, leg pain, and other symptoms such as numbness, tingling, weakness, or foot drop. Successful treatment of this problem remains a complex, puzzling, and expensive challenge. How so?

Well, the government reports that 1.65 billion dollars is spent in one year just in hospital costs for the surgical treatment of this problem. Yet, it’s not at all certain that this taxpayer money is spent wisely. Do patients get better and stay better? Are they able to do more with less pain? Given the way information is collected, we simply don’t know at this point what are the outcomes of surgery for lumbar spinal stenosis.

When surgery is done, there are two main choices: decompression (remove the disc and/or remove bone from around the disc) and fusion. The decision to perform one or both of these procedures is determined by surgeon preference, not always evidence of what works best. But don’t blame the surgeons for not following an evidence-based approach. The research to support treatment selection and patient selection for each treatment method just isn’t there yet.

You might ask if there isn’t a less invasive, less expensive way to treat this problem. There is — physical therapy, steroid injections, medications for pain control and to combat inflammation. But there’s not enough strong evidence to support these approaches either.

In this commentary on the treatment of lumbar spinal stenosis, a well-known surgeon from Kaiser Permanente Center for Health Research (Dr. Richard Deyo) shares how the surgeon faces many challenges when dealing with this patient population.

Advancing age often comes with a whole host of other problems we call comorbidities. Additional health problems like high blood pressure, diabetes, heart disease, cancer, and so on add to the complexity of patient treatment. Younger, healthier, and less frail patients may be treated differently compared with older adults with more comorbidities.

Data collected from hospital records suggest that two-thirds of the patients having decompression and fusion are younger (less than 65 years old). The remaining one-third of the procedures are for just decompression and in the older group with more health problems. It makes sense that surgeons select lower-risk patients for the more complex procedures (decompression and fusion) but what does the evidence show?

That’s the problem. The research to show when to perform a fusion, when to use instrumentation (metal plates, screws, pins), and what type of fusion to do just isn’t available. Now with health care reform entering the picture, problems like spinal stenosis that affect many older adults and cost the government huge sums of money will get the attention they deserve.

The future of health care involving spinal surgery is expected to bring less invasive techniques that are safer and yield better results with fewer complications. Patients are going to be more involved in the decisions made about their care. Patient education about their condition, choices of available treatments, and expected outcomes (based on research evidence) will change the way decisions are made regarding surgery.

It’s predicted that in the future of lumbar spine surgery, surgeon preference won’t be the only deciding factor in whether decompression versus decompression plus fusion is used to treat spinal stenosis. And the role of less invasive techniques (e.g., interspinous process spacers, automated percutaneous discectomy) will be investigated more carefully and completely.

When it comes to treating Baby Boomers, they are active consumers. As the name suggests, the gray tsunami is going to change how medicine is carried out. They expect and even demand a patient centered consent process.

In other words, they want to know the who, what, when, where, and how of their condition and its treatment. They expect full disclosure including the pros and cons of each treatment, the costs of care, and the potential complications and expected outcomes.

Along these same lines, Dr. Deyo suggests that researchers need to get busy and find out more about the best way to treat lumbar spinal stenosis. Newer techniques are great but their benefit(s) must be proven, not just assumed. And finally, Dr. Deyo points out that surgeons will be expected to make the treatment decision an individual one based not just on their own preferences, but the preferences of their patients.

Sometimes we joke that surgery has advanced to the point that brain surgery can be done on an outpatient basis with no overnight stay in the hospital. In fact, that’s not far from the truth in some cases. Orthopedic surgery has also progressed to include minimally invasive (MI) techniques that no longer require an open incision. Hospital stays are greatly reduced with this approach.

There are many advantages to the minimally invasive techniques. Experts in favor of minimally invasive procedures say there is less soft-tissue trauma since the surgeon doesn’t have to cut through all the layers of muscles and connective tissue. For the same reason, there is less blood lost and less chance the patient will need a blood transfusion. The patient’s pain is less and the hospital stay is predictably shorter.

But there are still some studies that don’t show a huge advantage to the minimally invasive approach and especially for spinal fusions. Some of the technical complications might suggest open incision is less risky. With minimally invasive methods, the surgeon has a limited field of vision so the procedure can take longer. Any increase in time under anesthesia has its own risks.

To help with the debate of which is better, orthopedic surgeons in China directly compared minimally invasive surgery for lumbar spinal fusion to the open incision technique. One surgeon performed all of the operations. Sixty-two (62) patients with degenerative lumbar disease were divided into two groups. Half the patients had a one-level lumbar fusion using a minimally invasive approach. The other half had an open incision fusion.

The actual procedure performed in all cases was a transforaminal lumbar interbody fusion (TLIF). The TLIF technique is used to avoid the problems that come with entering the spine from the front (anterior approach). Transforaminal means the surgeon gains access to the spine from the back and side. The surgeon makes a posterolateral incision and removes one of the facet (spinal) joints so the disc can be taken out.

Interbody describes how the fusion is circumferential (all the way around and from front-to-back). Once the disc is removed, the two vertebrae are distracted or pulled apart gently and a special device called an interbody spacer is slid into the disc space. The spacer helps restore normal disc height. A normal disc space takes pressure off the spinal nerve roots as they leave the spinal cord and pass through the opening formed by the vertebral bones.

When performing a minimally invasive TLIF, the surgeon uses a special tool called a tubular retractor system. A small incision is made through the skin and soft tissues to allow the placement of a hollow tube down to the spine. The tube holds the skin and soft tissues open. There is less risk of scar tissue formation using these tubes to push aside muscle fibers.

The tube gives the surgeon a working channel through the muscles without cutting and stripping them away from the spine. The surgeon passes instruments through the tube to perform the fusion. A tiny TV camera on the end of the instruments allows the surgeon to view (on a computer screen) what’s going on inside the spine.

The exact steps taken in the minimally invasive procedure were described. Photos were provided of the incisions and retractors in place. Most of the fusions were done either at L4-L5 (very bottom of the lumbar spine) or L5-S1 (where the last lumbar vertebra connects to the top of the sacrum).

The authors used a wide variety of measures to determine the effectiveness of each technique and to compare outcomes. The very same factors named as “advantages” of minimally invasive surgery were the first units of measure. These included amount of blood lost during the operation, number of transfusions needed, number of days in the hospital, and intensity of postoperative pain. Other outcomes used to measure and compare results included length of time each patient was in surgery, number and types of complications, and how long it took to get the patient back up on his or feet walking.

Soft tissue injury was assessed using a particular lab value (blood test) called serum creatine kinase

. X-rays of the spine were taken before and after surgery. Functional level was measured using a well-known test called the Oswestry Disability Index (ODI). Everyone was followed for at least two years. And the results? [Imagine a drum roll here].

In almost every measurement, the minimally invasive technique won out. There was less blood lost, fewer transfusions, less intense pain, and lower creatine kinase levels (an objective measure indicating less soft tissue damage). Patients in the minimally invasive group were able to get up and walk three days after surgery.

It took an average of two extra days for the open incision group to accomplish the same thing. Most of the difference in time-to-ambulation (walking) was credited to less pain from less nerve, muscle, and other soft tissue disruption in the minimally invasive group. As expected and predicted by other studies, the minimally invasive approach took longer by about one-quarter of an hour (15 to 16 minutes). With all the plusses of this procedure, this one minus isn’t too bad.

In summary, recovery time was faster with less trauma to the soft tissues using the minimally invasive approach to transforaminal lumbar interbody fusion (TLIF). Pain levels and function were equal in both groups during the first three to seven days (one week post-op). There were some complications but these were isolated (only one patient with each complication reported) and apparently not specifically caused by the type of fusion procedure performed. The results of this study add to the evidence so far that the minimally invasive transforaminal interbody fusion (TLIF) is a superior technique over open incision TLIF.

Acute lumbar disc prolapse can be very painful. Back pain that goes down the leg (called sciatica) often brings the patient in to the physician’s office for help. Pain is managed with physical therapy and medications such as antiinflammatories.

Another form of drug therapy is with muscle relaxers/relaxants. The most common drug family of muscle relaxants used are the benzodiazepines (e.g., Librium, Valium). These drugs are also used to treat anxiety because they have a sedative effect. But concerns about side effects of benzodiazepines has brought into question whether they should be used at all for acute low back pain associated with lumbar disc prolapse.

In general, benzodiazepines are safe and effective when used on a short term basis. Long-term use is really the sticking point. These medications can cause adverse psychological and physical effects. Patients can become addicted and become physically dependent on the drug. Withdrawal symptoms may occur when attempting to stop taking them.

In this study, the role of one specific benzodiazepine (diazepam, also known as valium) in the management of acute low back pain with sciatica is reviewed. All 60 patients enrolled in the study had been diagnosed as having a lumbar disc prolapse using imaging studies (CT scans and MRIs).

A disc prolapse is a type of disc herniation. The three main types of disc herniation can actually be divided into disc prolapse, disc herniation, and disc sequestration. In the case of a prolapse, the disc is bulging.

The inner portion of the disc (the nucleus) is intact has migrated or moved into the outer covering called the annulus. The direction of the disc material is usually backwards toward the spinal canal. A bulge or prolapsed disc can be large enough to actually press against the nearby spinal nerve root causing back and/or leg pain (sciatica).

The pain causes muscles to contract and hold that contracted position. The result is a protective muscle spasm that really only increases the pain. Muscle relaxants like diazepam are meant to break the pain-spasm cycle by relaxing the muscles in spasm. But do they really work? That’s the question addressed here.

Patients in the study were divided randomly into two groups. Everyone received physical therapy plus either diazepam (Valium) or a placebo (sugar pill). It was a double-blind study, which means none of the key players (patients, physicians, or physical therapists) knew who was receiving a placebo versus the diazepam. Patients were allowed to take a pain reliever/antiinflammatory (Voltaren) as prescribed by their physician.

A specific type of physical therapy approach was used with each patient. The concept is to find the direction of spinal movement that does not cause pain and does not reproduce the sciatica. The patient is then taught how to safely move in that direction repeatedly. The goal is to reduce the leg pain and centralize or move the pain to just the low back region (without leg pain).

Results were measured after seven days of treatment and again after six weeks and later one year after treatment. Per cent of total pain that was centralized (moved from down the leg to the low back) was the main measure. Other outcomes measured included intensity and duration of pain, muscle strength, ability to work, ability to walk, mobility (touching fingers to toes), and amount of pain medication used.

Surprisingly, the patients who received a placebo (sugar pill with no active ingredients) had the best pain relief and were in the hospital the shortest time. Return-to-work was faster in the placebo group. Patients taking the placebo were able to walk farther sooner than those patients taking the valium. Patients taking the valium were also more likely to ask for more medication and to take it over a longer period of time.

The authors concluded that benzodazepines should not be used for pain control in patients with sciatica from disc prolapse. In this study, pain was reduced much more effectively in the placebo group than in the group taking diazepam (Valium).

It has been suggested that muscle relaxants actually work against the goal of taking pressure off the spinal nerve. Muscle spasm and tightness can aid in putting pressure on the spine to maintain a position that will push the protruding disc back in place. The use of antiinflammatories, analgesics (pain relievers), and physical therapy remain the most effective management plan for this problem.

Getting a handle on what kind of pain medications work best for back pain is not an easy task. There are just so many variables to consider and compare. Does the patient have back and leg pain or just back pain? Does the patient take the prescribed drug for four weeks? Six weeks? Longer?

Researchers try to look at all the studies and combine results for a better understanding of effects. But according to pain research done in Europe, the design of each study isn’t similar enough to really allow such a meta-analysis. For example, sometimes patients are given drug combinations rather than a single drug. The dosage might be increased until it reaches a point where it’s effective and the side effects are tolerable or patients may be given the same dose from day one.

There are other confounding factors. Patients may stop taking the drug and withdraw from the study for any number of reasons. It could be they experienced no pain relief or there might have been unpleasant side effects, so the patient(s) quit taking the medication.

When the patient stops taking the drug but remains in the study, it is referred to as discontinuation. When the patient stops taking the drug and no longer participates in follow-up, the missing data falls under the category of withdrawal.

Classic studies include patients who are really receiving the medication while others get a placebo (sugar pill with no active ingredients). A review of the results of classic design trials showed a range of discontinuations or withdrawals that were similar between active medication and placebo groups. And there is evidence that some people keep taking the drug and staying in the studies even though they didn’t get a useful level of pain relief.

Once the data is all collected, the way in which it is analyzed is important. Lack of proper statistical analysis can result in poor-quality information that can’t be used in combination with other studies. The way patient outcomes are defined from study to study can be a real challenge. Some researchers use 30 per cent reduction in pain as the success point. This is not a standard cut-off value, so again, not all studies can be compared because of differences like this.

In general, research to study pain relieving medications given for more than six weeks as the primary treatment for chronic low back pain is very limited. Good research design, valid trials, and successfully capturing the effects of each drug treatment are all problem areas in this type of research. Studies that only report that the drug worked but nothing else make it difficult to compare between this drug and that drug.

The authors of this research review offer several suggestions for improving research in the area of pain relievers for chronic low back pain. They make these suggestions after reviewing all the trials reported and carefully studying 14 randomised double-blind trials of good quality. Patients were all followed for at least six weeks. Medications included common narcotics and antidepressants used in pain control.

First, the diagnosis for each patient must be clear and reported consistently. This is crucial when including patients who have back pain only versus back and leg pain because the two groups may respond differently to the treatment under study.

Next, the way success is reported must be consistent across all studies. Is 30 per cent pain reduction enough to be considered successful? More? Less? A standard cut-off point would make it possible to compare the results of one study to another.

And finally, assessment of pain reduction should include how the change in pain has affected the patients. Questionnaires should be completed before and after treatment in order to assess the effect of pain (and then pain relief) on return-to-work, quality of life, and function in daily activities. Other areas of study could also be included such as how much the treatment costs and which method is most cost-effective.

The topic of isthmic spondylolisthesis comes up often in the orthopedic surgeon’s office. It’s a condition that develops in childhood but often shows up with symptoms of low back pain in early adulthood. What is it? What can be done about it?

By definition, isthmic spondylolisthesis is the forward slippage of one vertebra over another (the one below it). It happens because there is a defect (usually a tiny crack) in the pars interarticularis (one of the supporting columns of the vertebra). That defect develops early in life before the bones are fully grown and fused.

The last lumbar vertebra (L5) is the one most likely to slip forward (over the sacrum, S1). But isthmic spondylolisthesis can develop anywhere in the lumbar spine, particularly at the L4-L5 or L3-L4 levels.

It’s not something we know how to prevent, so most medical efforts are on the treatment side of things. The type of treatment recommended depends on the grade of the slippage. Low-grade spondylolisthesis means up to 50 per cent of the vertebral body has shifted forward. A shift forward of more than 50 per cent is classified as a high-grade slippage.

Studies have confirmed that the natural history of isthmic spondylolisthesis (i.e., what happens over time) has a very low incidence of progression. In other words, it stays the same and doesn’t get worse over time. Most cases of spondylolisthesis can be treated conservatively (without surgery). This is especially true for the low-grade type.

Conservative (nonsurgical) care involves physical therapy, activity modification, and sometimes bracing and/or pain relieving medications. Physical therapists teach the patients lifelong skills of management including core training, correct posture and lifting, stretching, and aerobic conditioning.

Surgery is considered under several conditions: 1) the patient does not improve with conservative care, 2) there is a high-grade slippage or a low-grade spondylolisthesis that is quickly progressing to a high-grade status, 3) pressure on the spinal nerve roots is causing significant pain, numbness, and/or weakness that hasn’t responded to conservative care.

That all sounds so easy to figure out — and for the most part, it is a treatment protocol that works well. What isn’t easy to decide on is the type of surgery required. Considerable debate and controversy exists among orthopedic surgeons over this topic. What’s the latest thinking here?

There are half a dozen surgical procedures that can be done. These range from simply removing bone from around the compressed nerve root to full reduction of the slip and total fusion of the spine at the affected level. And then there are an equal number of ways to perform the fusion procedure, so choosing the right one for each patient can be a challenge.

Children (pediatric cases) have to be handled differently from adults because they have not reached full skeletal maturity. So long as the bones are still growing and changing, surgery can’t be the same as it is for adults. Imaging studies such as X-rays can be helpful to the surgeon when deciding what to do and how to do it.

One of the big decisions is whether to 1) try and correct the slippage (called reduction), 2) reduce and then fuse that spinal segment in place, or 3) fuse it where it is (slipped forward). This decision is made based on patient age and symptoms (especially the presence of pain and/or nerve compression). The presence and severity of any postural deformities that have developed must be considered. And surgeon experience will also tend to dictate the type of surgery recommended.

Each of these surgical approaches has its pros and cons. Reduction is easier in children who are still more flexible and in whom the postural deformities haven’t become permanent. With severe slippage, fusion holds better if reduction can be done first.

But there are risks with reduction — the technique of shifting the slipped vertebra back where it belongs often causes injury or damage to the spinal nerve root nearby. If the surgeon is concerned about this complication, then a partial reduction might be done instead.

The decision regarding how to perform a fusion procedure presents its own unique challenges. The surgeon must decide whether to use an anterior approach (from the front of the spine) or posterior approach (from the back). Other options include somewhere in between (anterolateral or posterolateral) or circumferential (all the way around) fusion.

The use of metal plates, screws, pins, and type of bone graft material are additional considerations. Surgeons rely on personal experience (tracking their own patients’ results) along with reports in the literature about successful outcomes with each type of surgical approach. This information is evaluated separately for the pediatric and adult groups with this condition.

If you aren’t too dizzy thinking about all the decisions the surgeon must make when planning surgical treatment for severe slippage, please consider one more thing. The type of approach and method of fusion also depend on what spinal level is being corrected. Reduction and fusion surgery is different at L4-5 than it is at L5-S1. With an L4-5 correction, it’s one lumbar vertebra fused to another. With L5-S1, the last lumbar vertebra is being fused to the top or dome of the sacrum.

The authors of this review provide much to think about in the treatment and management of isthmic spondylolisthesis at all ages. Conservative care is the first line of treatment in most cases (children and adults) unless the slippage is severe and symptomatic.

Surgical treatment is not standard (there isn’t one procedure that fits all patients). With time and the results of ongoing studies, surgeons will find what works best for each patient based on grade, age, severity, and other significant factors. Review articles like this one from the North American Spine Society (NASS) will help keep surgeons up to date on the latest results in research.

What causes low back pain at work? Is it the lifting? The pushing? The pulling? Researchers from Canada have published a report on the 2,766 studies they found on low back pain in the work setting. Type of occupational setting included various levels of manual labor. There were firefighters, nurses, salespersons, kitchen helpers, postal workers, shipbuilders, physicians, and steel mill workers, to name a few.

In theory, it makes sense that shearing forces are applied to the spine during pushing and pulling activities. Load and compression on the intervertebral discs occur. But are these forces enough to cause overload injuries to the low back area?

In this systematic review, all available evidence was gathered, analyzed, and summarized. The search for published data on the topic included electronic databases well-known and respected such as Medline, EMBASE, and CINAHL.

Only 13 of the 2,766 studies met the necessary standards to be included. And an evaluation of the methods used in those studies showed that only eight of the 13 were high-quality. The remaining five were so low in quality, the reported results couldn’t be used.

What makes for a “good” or “high-quality” study? First, the authors of the study use statistical measures that are valid and have high methodological quality. That means the sample size (number of people enrolled in the study) has to be enough to be relevant.

In this case of looking at the effect of physical activity (pushing/pulling) on low back pain, it would be helpful if the task measured by each study was described quantitatively (how much load, how often, direction, duration).

And these factors should be examined in light of when and how the low back pain occurs. The result would be a measure called dose response (i.e., what type of load is linked with low back injury).

According to the results reported in the eight high-quality studies on this subject, there just isn’t enough evidence to say that pushing/pulling activities on-the-job causes low back pain. Nurses pushing and pulling heavy hospital beds do suffer low back pain. But whether it was the pushing/pulling activity or something else remains unproven. Likewise for any of the other workers engaged in occupations studied.

The results of this systematic review show the need for high-quality studies using a prospective cohort design. Prospective cohort means the workers are studied on an ongoing basis rather than asked after they have suffered a back injury what factors were involved.

This type of design helps eliminate what’s called recall bias. In other words, statistics gathered as the injuries occur are more accurate in detail (how, what, when) compared with asking workers weeks to months later what happened and how it happened.

In summary, there just isn’t enough evidence from high-quality studies to confirm a link between pushing and pulling work-related activities and low back pain. These activities may be a risk factor for low back pain but until enough evidence from high-quality studies is presented, it remains an unanswered question.

Disc degeneration and herniation are common problems leading to surgery to remove part or all of the protruding disc. But back and leg pain from disc problems can come back after surgery. The question is: where’s the pain coming from? Is it the same disc, scar tissue formed after the disc removal, a new disc herniation, or something else?

Recurrent lumbar disc herniation occurs in anywhere from five to 15 per cent of patients. So patients with back and leg pain that goes away after disc removal (a procedure called discectomy) but comes back six months (or more) later are faced with the decision about what to do.

If it’s scar tissue, more surgery isn’t going to help. Another procedure could just cause even more scar tissue. But if only part of the disc was removed and now the rest of it has herniated, then a second surgery might be needed. Disc reherniation doesn’t happen with total discectomy because the entire disc has already been removed. In the case of recurrent back pain accompanied by sciatica (pain down the back of the leg) after total discectomy, there may be another disc that is starting to herniate.

How can the surgeon tell what’s going on? There are a number of different factors that must be considered. The first is the type of surgical technique used to remove the first disc. There are several different ways to perform a discectomy.

The surgeon may use minimally invasive methods such as microdiscectomy. A small incision is made and the damaged portion of the disc is removed. A microscope helps magnify the disc so the surgeon can see the area clearly.

Another surgical technique is the endoscopic discectomy. This is another minimally invasive procedure. The surgeon uses an endoscope, which is a tube through which instruments can be passed to remove the damaged portions of the disc. The surgeon can see on a video screen as the disc is removed.

Sometimes surgeons combine parts of both procedures to perform what’s called a hybridization of techniques. The goal is to avoid bleeding and soft tissue damage while removing the offending disc. The hope is to reduce hospital time, use of narcotic (pain) medications, and get the patient back to work as soon as possible.

The use of imaging studies is another way surgeons have to diagnose recurrent disc herniation. Simple X-rays don’t show discs but they can help rule out other possible causes of back pain and sciatica such as fractures, spinal instability, or stenosis (narrowing of the spinal canal).

MRIs help show the difference between abscess, scar tissue, hematoma (pocket of blood), and disc herniation. Lab testing of blood also helps the surgeon tell if the new pain might be coming from infection.

Once an accurate diagnosis has been made, then the patient and surgeon can get down to the business of treatment. Conservative (nonoperative) care is almost always tried first. There’s no sense in doing another surgery if antiinflammatory medication, physical therapy, or steroid injection would take care of the painful symptoms.

Not everyone responds to conservative care. There are some patients who don’t get pain relief no matter what is done. The effect on their quality of life and ability to work is such that a second surgery to remove the rest of the offending disc can’t be avoided. Anyone with pressure on the nerves causing bowel and bladder changes is a candidate for surgery right away.

For those patients with spinal instability (the vertebrae are shifting back and forth or collapsing), surgery to fuse the segment may be indicated. This type of situation is most likely to develop in patients who have already had more than one disc herniation. The surgeon does what is needed to take pressure off the spinal nerve roots and then uses metal plates, screws, and bone graft material to fuse the segments together.

What’s the result of surgery for recurrent disc herniations? Is there a way to get better outcomes and avoid further disc herniation? Studies show good-to-excellent results after second surgeies in 70 per cent of patients who have just sciatica (leg but no back pain). Results are slightly better (80 per cent effective) for patients with both back and leg pain).

As with any surgery (whether it’s the first discectomy or a revision procedure), complications are a possibility. The more cutting that’s done on the surrounding soft tissues (muscles, ligaments, connective tissue), the greater the risk of infection.

Second surgeries are more likely to result in tears of the dura (lining around the spinal cord and spinal nerve roots). And, of course, the risk of scar tissue formation is much greater after a second surgery.

With at least 200,000 lumbar discectomies done every year for back pain and sciatica, improved surgical techniques and results are needed. Studies done so far have been fairly limited. Comparing one study to another is a challenge because so many different surgeons use hybridization techniques that aren’t the same from patient-to-patient or study-to-study.

Future studies are needed to identify patients who will respond the best to each type of procedure available. Less invasive techniques may eventually make it possible to reduce complications (including disc reherniation) and eliminate the need for second surgeries.