Low Back Pain Practice Questions

Guest host Dr. Kim Richards, PT, DPT, OCS helps go through some practice questions on low back pain. Like the OCS, these questions are case-based with a couple surprise twists. See how well you've been learning your lumbar spine material by testing your knowledge on these questions.

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Transcript

Hello and welcome back. Today we’re going to try something new. Today’s podcast is going to be focused on OCS practice questions. We’re going to go through a series of questions and break down how you should arrive at the correct answer. If you’ve been listening along to the low back pain episodes so far, this should be a great review of the material we’ve discussed.

This episode is also unique because I’m bringing on a special guest, Dr. Kim Richards. Kim graduated with her DPT from Columbia University in 2006, and is also a Board-Certified Orthopedic Clinical Specialist. Kim worked as a part-time instructor at Georgia State University from 2013-2018, and she is now my coworker and friend at our private outpatient clinic. Welcome, Kim.

Thanks for inviting me on, David! I think this will be a fun discussion.

So let’s get started with the first case.

A 39 year-old F presents to you with complaints of R-sided LBP after spending several hours over the weekend raking and bagging leaves. She is one year post partum and has had a history of episodic LBP that is typically aggravated by heavy household and yard chores and typically subsides on its own after a few days. She reports that she can typically “crack her back” by lying on her side and twisting and this alleviates her pain temporarily. Her pain is rated as 4/10 and is an “ache” that also “feels tight.” The patient is very active in her job and participates in high intensity workouts 5 days per week. Her pain does not prohibit her from exercising or performing her household or work duties. She denies pain radiating to the leg but notes that it occasionally feels like it radiates into her PSIS region and lateral hip. She also denies numbness and tingling into her buttock or leg. She exhibits an active straight leg raise of 95 degrees on the left and 100 degrees on the right. Her current pain can be reproduced with L side bending, trunk forward flexion, prolonged standing, and repetitive bending or stooping to pick up her children or objects from the floor. She reports feeling like her “right side needs to be stretched out” and her symptoms improve with general movement.

1. Based on this patient’s presentation, she best fits into which classification?

A.  Directional preference

B.  Symptom modulation

C.  Manipulation

D.  Movement control

The answer we’re looking for here is D, movement control. You might be more familiar with the term stabilization, but remember that in the 2016 treatment-based classification, we’re starting to move away from that term. The key features here are the moderate pain level, straight leg raise past 91 degrees, and age less than 40. She does like self-manipulation, which might make that option tempting, but she doesn’t fit the manipulation clinical prediction rule. And clearly manipulation isn’t getting the job done for her.

Next question: 

2. When treating this patient, which approach best represents the order of interventions?

A.  Address right quadratus lumborum flexibility impairment, followed by prescribe motor control exercises, followed by incorporate motor control into raking and vacuuming

B.  Prescribe motor control exercises, followed by prescribe trunk strength exercises, followed by perform joint mobilizations to the lumbar spine

C.  Prescribe active rest, followed by perform lumbar extension exercises, followed by prescribe motor control exercises

D.  Perform thrust manipulation to the lumbar spine, followed by prescribe trunk strength exercises, followed by prescribe lower quadrant nerve glides

So this is taken directly from the 2016 TBC, but it follows good clinical reasoning anyway. First you fix the mobility impairment, then reeducate in a new range of motion so they can utilize that range, and then you take that into her functional tasks. So for this person, she gets symptoms when she does her higher level functional activities, so that’s where we want her to be able to work without pain reproduction.

 So the right answer on this question is A, we address right quadratus lumborum flexibility impairments, then we prescribe motor control exercises, and then we incorporate those motor control exercises into raking and vacuuming

Third question:

3. As this patient’s current episode of low back pain resolves, what is the best strategy for progressing her plan of care?

A.  Assess her technique for performing self lumbar manipulation and instruct her in performing this movement every day.

B.  Include progressive pushing and pulling exercises in her sessions and home program.

C.  Advise her on a full stretching routine for her trunk and legs.

D.  Teach her nerve glides to perform as part of her home exercise program. 

Again, we’re following the 2016 TBC here, where patients are moved along a continuum from symptom modulation towards functional optimization. As this patient’s pain improves, we want to progress her toward her typical higher level activities. So the correct answer for this question is B, include progressive pushing and pulling exercises in her sessions and home program.

Alright, let’s go through a new case:

A 52-year-old male patient presents with a chief complaint of low back pain radiating down his lateral left thigh to the knee. He reports the pain started 1 week ago after helping a friend move. He just saw his primary care physician, who prescribed hydrocodone for pain. His pain is 8/10, it is worse at night, and it is constant, and he also reports feeling funny sensations on his lateral thigh and sometimes down to the top of his foot. He denies bladder changes, but reports onset of constipation since the injury. Other relevant medical history includes prostate cancer, hypertension, hyperlipidemia, and diabetes. He manages these with metoprolol, atorvastatin, and metformin. His ODI is 41%, and his FABQ-Work is 19. Physical examination reveals the following:

-        Spring testing is very painful at L3-L5.

-        Positive crossed straight leg raise

-        Lumbar flexion and extension cause pain to move to the anterior lower leg.

-        When returning to neutral from a flexed position, he deviates from the frontal plane.

-        Muscle testing reveals L ankle dorsiflexion is 3/5

Which of the following actions is most appropriate for this patient?

A.     Treat with lumbar manipulation

B.     Treat with prone lumbar traction

C.     Treat with lumbar stabilization exercises

D.    Refer to MD to rule out cancer

This is a very tricky question, because there are several features from multiple classifications. Let’s go through some reasoning.

The answer is B, treat with prone lumbar traction. This is not the treatment you will pick most of the time, but as we’ve discussed, our treatment-based classification system and the CPG recommend lumbar traction when the patient has signs of nerve root compression and peripheralizes with both flexion and extension. 

There are several features that make manipulation appealing: the pain is acute, and before your examination, there is no pain below the knee. However, you need at least 3/5 components of the lumbar manipulation cluster for a 68% chance of success, and we don’t have any other components here. The FABQW is close, but it has to be <19, not 19. Moreover, by the time we finish our exam, we have pain below the knee. 

The factor here that favors stabilization is the aberrant movements when performing lumbar AROM. However, if you’re following Alrwaily’s treatment-based-classification system, you’ll recognize that the pain is too high, and a symptom modulation approach, like traction, would be preferable. 

Finally, although this patient has several red flags: age over 50, history of cancer, night pain, and constant pain, there is a mechanism of injury. And since night pain and a patient report of “constant” pain might be expected for mechanical back pain at this early, severe stage, it would be best to follow a treat-and-see approach before referring out. If the patient fails 30 days of conservative management, then we should refer for a more complete work-up.

Next question:

Which of the following medications are most likely to cause constipation?

A.     Metoprolol

B.     Atorvastatin

C.     Metformin

D.    Hydrocodone

In this particular case, I threw in the sudden onset of constipation to see if anyone would panic about cauda equina syndrome. But remember that when we discussed cauda equina red flags, findings of urinary retention and fecal incontinence would be more concerning than constipation. And in this case, the MD prescribed an opioid, hydrocodone, immediately following the injury. Constipation is a common side effect of opioids. Yes, you will need to know the common side effects of some common medications for the OCS exam—especially side effects that might mimic conditions or red flags, because you will need to factor that into your clinical decision-making in real life too. Moreover, since opioids are such a hot topic in healthcare right now, it wouldn’t surprise me if some questions about opioids pop up. So in this list, hydrocodone is the medication likely to cause constipation. Atorvastatin and metformin, on the other hand, may cause diarrhea.

Last question for this case:

Based on this patient’s clinical presentation, in which other muscle would you expect to find weakness?

A.     Flexor hallucis longus

B.     Gastrocnemius

C.     Extensor hallucis longus

D.    Vastus medialis

 Here, you have to know two pieces of information: which nerve root is affected in the case above, and which other muscle in this list is innervated by the same level. If you recall, the case described pain radiating down the lateral thigh and anterior lower leg, with paresthesias down to the top of the foot. We also have tibialis anterior weakness. The pain and sensation changes follow an L5 dermatome pattern, and the tibialis anterior is innervated by L4, L5. In this list, The extensor hallucis longus also shares innervation from the L5 level. It is innervated by L5 and S1.

The OCS loves questions like this, and I would expect you to see a lot of questions that require you to know your dermatomes, myotomes, and peripheral nerves. 

Here’s another case: 

A 62-year-old female patient presents to the clinic with a 10-year history of back pain. She attributes her problems to genetics and says her mother and grandparents had “bad backs” too. She has difficulty pinpointing the pain, but she says it spreads across the low back and sometimes into both buttocks. She has been going to a chiropractor and an acupuncturist for years to try to fix the pain. She says when it gets bad, the only thing that helps is lying on a hot pack. She is apprehensive about moving wrong and making her back worse. She reports that she has a lot of other aches in her knees and feet, and she thinks she might have fibromyalgia. She is a 1 pack/day smoker. Physical examination reveals the following:

-        Lumbar flexion, extension, and lateral flexion all limited 50% with pain at end range

-        Global tenderness in B paraspinals, quadratus lumborum, and posterior hip muscles

-        Hip IR 20 degrees bilaterally

Which of the following topics of education is most important to discuss with the patient first?

A.     The most probable pathoanatomical cause of her pain

B.     Smoking cessation

C.     The strength of the human spine

D.    A typical physical therapy plan of care

The correct answer is C, the strength of the human spine. This is one of the six topics of education that the CPG recommends for back pain. This patient’s subjective report indicates she may have some fear of movement and negative beliefs about her spine. We need to address these. Although smoking cessation would be a great discussion to have, it’s not the most important thing to discuss first. Education on a PT plan of care is important, but we really haven’t completed our physical exam or reached a point in discussing our patient’s goals, fears, and beliefs to really get into discussing a plan of care. And I hope no one thought it was a good idea to wildly speculate about pathoanatomical sources of pain here.

Next question:

Which of the following treatments would be best for this patient?

A.     Moderate intensity lower extremity strengthening

B.     Soft tissue mobilization to the lumbar and posterior hip musculature

C.     A multimodal approach of lumbar interferential current, anti-inflammatory modalities, and lumbar manipulation

D.    Sub-maximal endurance exercises

In this situation, we have a chronic pain patient who reports widespread pain and global tenderness. These factors should clue us into possible central sensitization. According to the CPG, we have A-level evidence for prescribing submaximal endurance exercises when patients have chronic back pain with generalized pain. The other options here aren’t necessarily contraindicated, but they aren’t the best choices based on our available evidence. 

Okay, one last case:

A 68-year-old patient presents with a chief complaint of burning in the back of his legs when he is walking. He reports that after walking for about a quarter mile, he feels burning in his calves. He eventually has to stop and sit down for the pain to go away. He reports the same thing happens when he rides his bike. Once he stops and sits down, the pain stops quickly. Physical examination reveals the following:

-        Lumbar flexion is full and pain-free

-        Lumbar extension is limited and painful in the back

-        Spring testing reveals lumbar hypomobility

-        LE strength testing is WNL

Which of the following treatments would be most effective for this patient?

A.     Repeated sets of level treadmill walking to the point of near maximal pain, followed by rest.

B.     William’s flexion exercises

C.     Bodyweight supported treadmill training

D.    Joint mobilization targeting the hips and lumbar spine

The correct answer is A. repeated sets of level treadmill walking to the point of near maximal pain, followed by rest. This case is designed to look a little bit like lumbar stenosis, but it’s not. Yes, it involves burning in the legs with walking, but the burning also occurs while riding a bike. This is not typical for lumbar stenosis. It is more likely that this patient is experiencing intermittent claudication due to peripheral arterial disease. Don’t let things like painful lumbar extension throw you off if the pain is different from the chief complaint. Here, the pain was just in the back. So if lumbar stenosis was the diagnosis, bodyweight supported treadmill training would probably be the best answer, and the other two options would be appropriate treatments. But since this is intermittent claudication, we’ll be doing repeated sets of level treadmill walking.

I hope this gives you a taste of how the OCS exam is likely to ask their questions. If you want more opportunities to practice, you can sign up to have practice questions emailed to you at our website, PhysioFieldGuide.com. 

This episode will wrap up our series on low back pain for now. We’re excited to move on to our next topic. So stay tuned, and you should hear from us again next week.