Low Back Pain CPG (2012): Prevalence, Risk Factors, and Clinical Course

Dr. David Smelser introduces the 2012 low back pain Clinical Practice Guideline and covers the sections on prevalence, risk factors, and clinical courses. A couple case studies reinforce how this information might be used on the OCS exam.

Transcript

Hello future board-certified specialists and welcome back. Today we’re going to get into the messy world of low back pain.

But first, two brief personal notes. First, if you have wondered where Austin’s soothing voice has been since the introductory episode, I’ll fill you in: Austin just bought a house, so he has been spending all his free time tearing up old carpet and sanding and repairing hardwood. So while we are learning about back pain, Austin is choosing to experience it. You will have to put up with just me for a short while longer, and then he will be returning.

Second, I want to encourage you to follow us on Facebook and Instagram. We plan to post some material—particularly on Instagram—so I don’t want you to miss it. Now, on to back pain.

Today we are introducing the 2012 Low Back Pain Clinical Practice Guideline. All of the Clinical Practice Guidelines, or “CPGs,” are critically important for you to review. This is for two main reasons. First, one main goal of the OCS exam is to evaluate whether the test takers are up to date on the latest evidence. The CPGs are summaries and analysis of what the Orthopedic Section of the APTA believes to be the most relevant research on a given topic. So instead of trying to look up every article on low back pain and synthesize all the conflicting research, you can look at the CPG, where the authors have done it for you.

The second reason you need to know the CPGs, is because the OCS questions are written by busy clinicians like Austin and me. And each question has to be written with a citation from quality reference. So where is Austin going to go to find material to write an OCS question after he has spent all day pulling up carpet and sanding floors? He’s probably going to use the easiest source available: the CPGs.

One big caveat about the CPGs is that they are technically only good for about 5 years. Since there is new research coming out all the time, after a few years, the CPG no longer reflects all of the evidence available. This low back pain guideline was written in 2012, so it is long overdue for an update. You should still read it and know it because busy OCS question writers are going to use it for question material. But you also need to know some of the big articles that have been published since 2012. So we’re going to do some special episodes soon where we cover some of those articles as well.

Since we think it would be a good idea for you to read all the CPGs on your own, we’re going to focus our time in this podcast reading and summarizing the most important parts of the CPGs. This will help reinforce the material and clue you in to what we think is most important to know. Today, we’re going to cover the CPG sections on prevalence, risk factors, and clinical course.

Prevalence:

We all know back pain is a big problem and is getting worse. The OCS exam is going to be more interested in what you know about diagnosis, prognosis, and treatment than what you know about prevalence, so you shouldn’t expect a ton of questions on low back pain prevalence. With that in mind, we’re going to discuss the highlights, and then we are going to recap at the end of each section:

• Chronic back pain is becoming more common. In 1992, prevalence was estimated at 3.9%. In 2006, it was at 10.2%.
• Individuals who have activity-limiting low back pain often experience recurring episodes with estimates ranging from 24% to 33%. 
  • So if you have a patient case on the OCS exam where an individual has had a history of activity-limiting low back pain and has a recurrence, you shouldn’t necessarily panic and send them to a spine surgeon. Remember: recurrences are normal. 
• Women tend to have a higher prevalence of back pain than men.
• And prevalence increases as we age up until 60-65 years old. After that, prevalence no longer increases. This is a little counter-intuitive, because degeneration continues to get worse after 65 years old, but pain does not.
• Lower education status is associated with increased prevalence of back pain, longer duration, and worse outcome. So there are some socioeconomic factors that increase the chance of developing low back pain.
• Occupational status affects prevalence, with higher physical demand being associated with more low back pain than more sedentary jobs.

To summarize:

• Chronic back pain is spreading.
• Recurrences are normal for those who have activity-limiting low back pain.
• At least to some degree, women, older individuals up to 65 years old, those with lower education, and those with more physical jobs demonstrate higher prevalence of low back pain.

Let’s move on to risk factors. Risk factors affect prognosis, which is something the OCS exam is going to test. So pay close attention to factors that may lead to a worse prognosis, a better prognosis, or factors that are just distractors but have no effect on prognosis.

First, physical risk factors:

• There is some evidence that back pain is associated with operating heavy equipment.
• Cardiovascular risk factors (hypertension, smoking, obesity, being overweight) are associated with sciatica.
• Degenerative changes on MRI, myelography, and CAT-scans are not strongly related to low back pain symptoms. More on this later. But for now, remember: if you’re comparing two patients, and one has a much worse sounding MRI, those imaging findings won’t necessarily correspond to worse symptoms or a worse prognosis.
• “There is inconclusive evidence for a relationship between trunk muscle strength or mobility of the lumbar spine and the risk of low back pain.” This is counterintuitive to us as PTs, so keep that in mind.

To summarize, operating heavy equipment and cardiovascular risk factors are associated with back pain and sciatica, respectively, but degenerative changes on imaging is not. Evidence is inconclusive on trunk muscle strength and lumbar mobility.

Next, psychosocial factors. The CPG reads, “Psychosocial factors appear to play a larger prognostic role than physical factors in low back pain.” So this is very important to know.

• There is some evidence to suggest that fear may play a role when pain has become persistent.
• There is a growing consensus that distress/depression plays an important role at early stages, and clinicians should focus on these factors. I’ll repeat: the CPG says, clinicians should focus on these factors. If you get a case where a patient is showing signs of distress and depression, you cannot ignore it! That might mean educating the patient to reduce distress or fear-avoidance, or it might mean referring the patient to a healthcare provider equipped to treat depression.
• Third, expectations of recovery is a predictor of return to work. Patients with higher expectations of recovery had fewer absences from work than those with lower expectations.
• Finally, active coping styles are associated with better outcomes.

The CPG also notes that higher pain intensity is associated with worse outcomes.

And then it lists some factors that appear to have no association with back pain prognosis. This includes a prior history of back pain, smoking, and comorbidities. The CPG reads, "the clinical course for patients with comorbidities, who may seem more complicated at the start of treatment, is just as favorable as for those without such comorbidities.”

So to summarize:

• Psychosocial factors are more important risk factors then physical risk factors, and they need to be addressed.
• Expectation of recovery is an important predictor of recovery.
• High pain intensity is associated with worse outcomes.
• Comorbidities appear to have no association with back pain prognosis. And this really emphasizes how important the psychosocial factors are: if comorbidities are irrelevant to recovery but patient expectation is predictive of recovery, we need to be addressing those patient fears and expectations.

So what is the point of all of this? You could get a patient case with a lot of information, and then the question might ask you which factor has the greatest influence on the patient’s prognosis. For example, take John. John is a 48 year old male smoker who works a sedentary job. He has 4/10 central low back pain that has been going on for 8 weeks. He received an MRI four weeks ago that showed severe degenerative disc disease in L3-5. He reports that he thinks this is just part of getting older and there’s probably nothing that he can do about it except avoid making things worse. John is the sole provider for three children. What factor has the greatest influence on his prognosis? Is it his age, his smoking status, his work status, his family status, his pathoanatomical changes, or his psychosocial status? Hopefully you recognize some warning signs of fear-avoidance and passive coping in this case. Smoking status, sedentary job, and MRI findings are all distractors that sound like they would indicate a poor prognosis, but really they have no effect here. Psychosocial factors play a much bigger role.

Let’s conclude by covering the clinical course of low back pain. The CPG discusses how back pain can be acute, subacute, or chronic, but since recurrences are so frequent, it can be difficult to group people into those categories neatly. So the CPG summarizes some really important risk factors for developing recurrent or chronic low back pain:

“Clinicians should also consider screening for and addressing factors that increase the probability of developing recurrent or chronic low back pain. Prognostic factors for development of recurrent pain include (1) history of previous episodes, (2) excessive spine mobility, and (3) excessive mobility in other joints.” I’ll read that again. “Prognostic factors for development of recurrent pain include (1) history of previous episodes, (2) excessive spine mobility, and (3) excessive mobility in other joints.”

Then it goes on to talk about chronic pain: “Prognostic factors for development of chronic pain include (1) presence of symptoms below the knee, (2) psychological distress or depression, (3) fear of pain, movement, and reinjury or low expectations of recovery, (4) pain of high intensity, and (5) a passive coping style.” Once more, “Prognostic factors for development of chronic pain include (1) presence of symptoms below the knee, (2) psychological distress or depression, (3) fear of pain, movement, and reinjury or low expectations of recovery, (4) pain of high intensity, and (5) a passive coping style.”

You will notice that this generally lines up with the risk factors associated with back pain in general, but because recurrent and chronic low back pain are so costly, the CPG says, “clinicians should place high priority on interventions that prevent (1) recurrences and (2) the transition to chronic low back pain.” So with that in mind, it is very important that you can recognize risk factors for developing recurrent and chronic low back pain.

Since the CPG says clinicians need to place a high priority on interventions that prevent recurrent and chronic low back pain, you might get a back pain case like this: Jane is a 25-year-old female with onset of 6/10 central low back pain two weeks ago after “overdoing it” working in the yard. She reports that the pain grabs her suddenly, so she is afraid to move or do anything, because she thinks her back might go “out” and never go back “in” again. Her pain does not peripheralize with movement. She has hypomobility at L4 and L5 with spring testing, and her hip internal rotation is 40 degrees bilaterally. What intervention should be performed first? A. Traction, B. Manipulation, C. Mobilization, or D. Education on the inherent strength in her spine and overall positive prognosis of low back pain?

You will notice that several of these answers are perfectly appropriate treatments. She meets the clinical prediction rule for lumbar manipulation, so manipulation would be appropriate. Although manipulation has shown to produce faster results than mobilization, there is also evidence that mobilization would be appropriate. But education is the most important treatment here. She demonstrates a very high level of fear and movement, and we need to address that to reduce the chance of developing chronic pain.

Let’s do one more case. Jim is a 17 year old gymnast with a history of back pain off and on for several years. He had an increase in symptoms in his back and buttock 3 weeks ago after increasing his gymnastic training. His pain gets worse with activity but doesn’t go away fully with rest. Jim’s active range of motion reveals full lumbar range of motion with pain at the end range. Spring testing reveals hyper mobility in his lumbar spine with mild pain at L4 and L5. Jim’s Beighton Score is a 7. Which of the following conditions is Jim at increased risk of having or developing? Is it ankylosing spondylitis, cancer, chronic pain, or recurrent back pain?

Jim meets all the risk factors for developing recurrent pain. He has a history of back pain, he has hyper mobility in his lumbar spine, and his Beighton score—which assesses joint hyper mobility is a 7 out of a possible 9 points. Remember that a score of at least 5 indicates hyper mobility.

Let’s finish with a quick episode recap:

• There’s no clearly defined cause for low back pain, and prevalence studies are unclear. However, prevalence seems to be greater for women, aging individuals up to 65 years old, those with lower education status, and those with physical jobs.
• Evidence for physical risk factors is also conflicting, but operating heavy machinery appears to be associated with low back pain and cardiovascular risk factors appear to be associated with sciatica.
• In contrast, degeneration on imaging appears to have no association with risk and prognosis.
• Psychosocial factors are more important than physical risk factors. These include fear, distress and depression, low expectations of recovery, and passive coping styles.
• PTs need to be able to recognize and address prognostic factors leading to recurrent pain and chronic pain.

That wraps up our discussion on prevalence, risk factors, and clinical course of low back pain. We’re going to continue to work through some highlights of the low back pain CPG and some of those additional important articles published after 2012 in the coming episodes, so stay tuned.