CARE DISCUSSION

INTRODUCTION

CARE DISCUSSION

You discuss your next patient with Dr. Lee.

You are working with Dr. Lee today. She hands you a triage note from the nurse regarding your next patient, Mr. Payne:

Forty-five-year-old male truck driver complaining of two weeks of sharp, stabbing back pain after lifting a 10-lb. box. The pain was better after a couple of days but then got worse after playing softball with his daughter. This morning his pain is so bad that he had trouble getting out of bed.

Dr. Lee provides you some background information about low back pain.

TEACHING POINT

Low Back Pain Prevalence, Cost, & Duration

Low back pain (LBP) is the fifth most common reason for all doctor visits. In the U.S., the lifetime prevalence of LBP is 60% to 80%. The direct and indirect costs for treatment of LBP are estimated to be $100 billion annually. Fortunately, most LBP resolves in two to four weeks.

CAUSES OF LOW BACK PAIN 1

CLINICAL REASONING

Dr. Lee continues: “There are many causes for LBP. For presenting symptoms that have a broad differential diagnosis, I find it helpful to think of systems of etiologies in which diseases or conditions can be categorized.”

TEACHING POINT

Common Causes of Back Pain

Musculoskeletal (MSK) and Non-MSK Causes of Back Pain

MSK Causes

Axial:

· Degenerative disc disease

· Facet arthritis

· Sacroiliitis

· Ankylosing spondylitis

· Discitis

· Paraspinal muscular issues

· SI dysfunction

Radicular:

· Disc prolapse

· Spinal stenosis

Trauma:

· Lumbar strain

· Compression fracture

Non-MSK Causes

Neoplastic:

· Lymphoma/leukemia

· Metastatic disease

· Multiple myeloma

· Osteosarcoma

Inflammatory:

· Rheumatoid Arthritis

Visceral:

· Endometriosis

· Prostatitis

· Renal lithiasis

Infection:

· Discitis

· Herpes zoster

· Osteomyelitis

· Pyelonephritis

· Prostatitis

· Spinal or epidural abscess

Vascular:

· Aortic aneurysm

Endocrine:

· Hyperparathyroidism

· Osteomalacia

· Osteoporotic vertebral fracture

· Paget disease

Gastrointestinal:

· Pancreatitis

· Peptic ulcer disease

· Cholecystitis

Gynecological:

· Endometriosis

· Pelvic inflammatory disease

· CAUSES OF LOW BACK PAIN 2

Most Common Causes of Back Pain

There are three major categories of back pain: mechanical, visceral, and non-mechanical.

Mechanical

· 97% of back pain

· No primary inflammatory or neoplastic cause

Visceral

· 2% of back pain

· No primary involvement of the spine, usually from internal organs

Non-mechanical

· 1% of back pain

· Other

The three most common causes of back pain are all mechanical:

1. Lumbar strain/sprain – 70%

2. Age-related degenerative joint changes in the discs and facets – 10%.

3. Herniated disc – 4%

Acute sciatica is lower back pain with radiculopathy below the knee and symptoms lasting up to six weeks. Sciatica is a common and costly problem, caused by a variety of conditions: disc herniation, lumbar spinal stenosis, facet joint osteoarthritis or other arthropathies, spinal cord infection or tumor, or spondylolisthesis.

Less common causes of mechanical back pain:

· Osteoporotic fracture – 4%

· Spinal stenosis – 3%

Uncommon causes of back pain:

· Pyelonephritis, a visceral cause, accounts for 0.4% of back pain.

RISK FACTORS FOR LOW BACK PAIN

CARE DISCUSSION

Dr. Lee suggests, “Now, let’s look a bit more at the risk factors for mechanical low back pain that you can review with Mr. Payne during your history.”

Dr. Lee continues, “The major task in treating back pain is to distinguish the common causes for back pain (95% of cases) from the 5% with serious underlying diseases or neurologic impairments that are potentially treatable.”

TEACHING POINT

Risk Factors for Low Back Pain

· Prolonged sitting, with truck driving having the highest rate of LBP, followed by desk jobs

· Deconditioning

· Sub-optimal lifting and carrying habits

· Repetitive bending and lifting

· Spondylolysis, disc-space narrowing, spinal instability, and spina bifida occulta

· Obesity

· Prolonged use of steroids

· Intravenous drug use

· Education status: low education is associated with prolonged illness

· Psycho-social factors: anxiety, depression, stressors in life

· Occupation: Job dissatisfaction, increased manual demands, and compensation claims

TEACHING POINT

Red Flags For Serious Illness or Neurologic Impairment with Back Pain

· Fever

· Unexplained weight loss

· Pain at night

· Bowel or bladder incontinence

· Urinary retention

· Neurologic deficits

· Saddle anesthesia

· Trauma

HISTORY 1

HISTORY

You and Dr. Lee take a few minutes to review Mr. Payne’s chart:

Vital signs:

· Temperature is 37 °C (98.6 °F)

· Pulse is 80 beats/minute

· Respiratory rate is 12 breaths/minute

· Blood pressure is 130/82 mmHg

· Weight is 77 kgs (170 lbs)

· Body Mass Index is 24 kg/m2

Past Medical History:Diabetes, well-controlled. Hypertension, fair control. Hyperlipidemia, fair control.

Past Surgical History: None

Social History: Works as a truck driver, which involves lifting 9-16 kgs (20-35 lbs) 4 hours of the day, married with 2 daughters,

Habits: Smoked one pack per day for 20 years. Quit smoking two years ago, drinks one to two beers occasionally on the weekends, no history of IV drug use.

Medication:

· Metformin 1000 mg PO twice daily

· Glyburide 10 mg PO twice daily

· Amlodipine 2.5 mg PO daily

· Lisinopril 40 mg PO daily

· Simvastatin 40 mg PO daily

Recommended Low Back Pain History

1. History of present illness.

· What is the location of the pain? Is it upper, middle, or lower back? Left or right side?

· What is the duration of the pain or how long ago did it start? Is it getting worse or better? Does the pain radiate? Pain that radiates below the knee- more consistent with sciatica; pain around the buttock- more consistent with a lumbar strain.

· What is the severity of the pain? Use a pain scale of 0 to 10 to make the severity somewhat more objective. Intensity of the pain.

· What is the quality of the pain? Is it achy, or sharp, or dull, or throbbing?

· Is the pain constant or intermittent? If intermittent, how often does it occur? How long does it last? Is it present at night or at rest?

· Are there associated symptoms (such as fever, weight loss, weakness, numbness, tingling)?

· Are there aggravating or alleviating factors? Aggravating circumstances (active vs. passive motion, day vs. night). Valsalva can increase pain from a herniated disk. Alleviating circumstances (medication, positioning-sitting, lying, standing). What has the patient tried to relieve the problem (what worked, what didn’t)?

· Any history of similar problems?

2. Pertinent past history. Recent illnesses, history of recent trauma or injury, patient’s occupation, previous history of a back injury, history of back surgery, cancer, or DM. (Fatigue is a nonspecific finding which may not help you to narrow your differential diagnosis.)

3. Review of systems. In order to narrow your differential diagnosis for the patient’s problem, a review of systems focused on pertinent positives and negatives is important.

· Neurologic symptoms: saddle anesthesia, lower extremity numbness, tingling, muscle weakness particularly in the lower extremities, fecal incontinence

· Urinary symptoms: urinary incontinence, urinary retention, hesitancy, frequency, dysuria

· Gastrointestinal symptoms: nausea, vomiting, hematemesis, hematochezia, constipation, diarrhea, acid reflux symptoms

· Constitutional symptoms: fever, unexplained weight loss

4. Current medications and allergies

HISTORY 2

You greet Mr. Payne and discuss his back pain.

After introducing yourself to Mr. Payne, you sit down across from him and begin your history, focusing on the key elements.

“Can you tell me about your back pain?”

“On a scale of 0 to 10, with 0 being no pain and 10 being the worst pain, how severe is the pain?”

“Have you found anything that improves the pain?”

“What dose of ibuprofen and naproxen were you taking, how often, and for how many days?”

“What about positions that make things better or worse?”

“Have you had back pain before?”

You complete your history with a review of systems and discover:

Review of Systems

Mr. Payne does not have numbness or weakness in his legs. The pain is better when he lies down. He has not had urinary frequency, dysuria, problems with bowel or bladder control, fever or chills, nausea or vomiting, or weight loss. He also reports no recent trauma or unrelenting night pain.

You excuse yourself from Mr. Payne to discuss your findings with Dr. Lee

SUMMARY STATEMENT

Mr. Payne is a 45-year-old male truck driver with a two-week history of low back pain that radiates down his left leg to the ankle. The pain is worse with sitting and improves with the supine position. He reports no history of trauma, fever/chills, night pain, urinary symptoms, and bowel or bladder incontinence.

The ideal summary statement concisely highlights the most pertinent features without omitting any significant points. The summary statement above includes:

1. Epidemiology and risk factors: 45-year-old male; occupation: truck driver

2. Key clinical findings about the present illness using qualifying adjectives and transformative language:

· Pain present for two weeks

· Pain radiates down left leg

· Pain worse with sitting and improves with supine position

· No history of trauma

· No fever/chills

· No night pain

· No urinary symptoms

· No bowel or bladder incontinence

Mr. Payne is a 45-year-old male truck driver with a two-week history of low back pain that radiates down his left leg to the ankle. The pain is worse with sitting and improves with the supine position. He reports no history of trauma, fever/chills, night pain, urinary symptoms, and bowel or bladder incontinence.

The ideal summary statement concisely highlights the most pertinent features without omitting any significant points. The summary statement above includes:

1. Epidemiology and risk factors: 45-year-old male; occupation: truck driver

2. Key clinical findings about the present illness using qualifying adjectives and transformative language:

· Pain present for two weeks

· Pain radiates down left leg

· Pain worse with sitting and improves with supine position

· No history of trauma

· No fever/chills

· No night pain

· No urinary symptoms

· No bowel or bladder incontinence

Mr. Payne’s presentation of acute low back pain radiating to the leg that is worse with sitting is most consistent with either lumbar strain or lumbar radiculopathy, which are among the most common causes of low back pain. Lumbar radicular symptoms may be caused by any process that compresses a nerve root as it exits the spine. Causes include disc herniation, degenerative arthritis with osteophyte development, and spondylolisthesis. Degenerative arthritis is more common in older patients, though it can happen as early as one’s 40s, as in Mr. Payne. Spondylolisthesis can happen at any age.

Spinal stenosis is less likely, as it typically presents as pain radiating to the legs (bilaterally more commonly than unilaterally) when walking. Symptoms are relieved by sitting. Mr. Payne lacks any systemic symptoms to suggest infection (prostatitis, pyelonephritis). Malignancy is good to remember, particularly in patients with a known primary cancer. It is less likely as an initial presentation of low back pain in a healthy 42-year-old. Ankylosing spondylitis typically has a more insidious onset and is characterized by non-radiating back pain that is alleviated by activity and worse at night.

TEACHING POINT

Differential for Low Back Pain

Lumbar strain	· The most common cause of acute low back pain in adults · Typically has an acute or sub-acute onset after an injury or precipitating activity (e.g., moving furniture)  · Pain is typically worse in the paraspinal muscles lateral to the spine and may be bilateral or unilateral · Pain may radiate down one or another leg · Pain is worse after periods of immobility and with particular movements (depending on where the strain is)
Disc herniation	· May have acute or sub-acute presentation · May be precipitated by a sudden injury  · Pain is often worse when the hips are flexed, as in sitting · Location of pain depends on the level of the herniation
Degenerative arthritis	· Increasingly common with advancing age · If an osteophyte impinges a nerve root can cause radicular symptoms in that nerve’s distribution · Has a more insidious onset
Spinal stenosis	· Caused by central deformity compressing the cord, such as by central disc herniation, spondylolisthesis, osteophyte, or mass · Hallmark symptom is pain radiating to the legs (bilateral more common than unilateral) that is brought on by walking or standing (sometimes called pseudoclaudication) · Sitting relieves the symptoms
Spinal fracture	· Not likely without a history of trauma. · Bony point-tenderness in a patient with low back pain should prompt an x-ray to evaluate for fracture
Cauda equina syndrome	· Should always be considered due to the seriousness of the consequences. · Occurs when a large mass effect (such as an acute disc herniation or a tumor) compresses the cauda equina, causing pain radiating down the leg and can be accompanied by weakness and numbness of the leg. · True emergency. Decompression should be performed within 72 hours to avoid permanent neurologic deficits.  · Low on the differential if the patient denies problem with bowel or bladder control.
Pyelonephritis	· Unlikely with lack of fever and urinary symptoms.
Malignancy	· Important consideration. A very serious, although uncommon, cause of back pain. · Unlikely without a history of cancer. · Back pain due to malignancy is localized to the affected bones, it is a dull, throbbing painthat progresses slowly, and it increases with recumbency or cough. · More commonly seen in patients over 50.
Ankylosing spondylitis	· Chronic, painful, inflammatory arthritis primarily affecting the spineand sacroiliac joints, causing eventual fusion of the spine. · Often seen in patients 15-40 years old, associated with morning stiffness and achiness over the sacroiliac joint and lumbar spine.
Spondylolisthesis	· Anterior displacement of a vertebra or the vertebral columnin relation to the vertebrae below. · Can occur at any age. · Causes aching back and posterior thigh discomfort that increases with activity or bending.
Prostatitis	· Can cause referred LBP in men. · (Pelvic inflammatory disease and endometriosis in women can cause referred LBP). · Expect to find evidence of infection in the history.
Pancreatitis	· Pancreatitis and other gastrointestinal diseases such as cholecystitis and ulcers can cause LBP via visceral pain. · Usually associated with other abdominal symptoms.

COMPONENTS OF MECHANICAL LOW BACK PAIN

Dr. Lee explains the complexities of back pain.

Dr. Lee tells you, “On physical exam, you can discover problems with the bony structures and muscles of the spine through inspection of posture, contour, and symmetry, palpation of the bony prominences, and range of motion testing.

A solid understanding of the neurological exam of the lower extremity will help you determine if the pain is due to nerve impingement or from muscle and bone.”

TEACHING POINT

Anatomy of Mechanical Lower Back Pain

Mechanical lower back pain generally involves one or more of the following:

1. Bones of the spine

2. Muscles and ligaments surrounding the spine

3. Nerves (the nerves entering and exiting the spinal cord or problems with the cord itself)

4. STANDING BACK EXAM

Dr. Lee performs the back exam.

You and Dr. Lee return to examine Mr. Payne together.

TEACHING POINT

Approach to the Physical Exam for Back Pain

Perform the back exam systematically in sequential order with the patient:

1. Standing

2. Sitting

3. Supine

Physical Exam for Back Pain—Standing

Throughout the whole exam make certain to note how your patient is sitting, standing, and walking in general, asking yourself, “What is his degree of impairment?” and “How uncomfortable is he?”

I. Inspection: Look at posture, contour, and symmetry. Also, inspect overlying skin to check for any lesions or abnormalities.

· Check for lordosis

· Check for kyphosis

· Check for scoliosis

Slight scoliosis may be more easily visualized during lumbar flexion. This is performed by having the patient stand with their feet and hands together, like they are about to dive off a diving board, bending forward toward their toes. Look out across the back to see if the shoulders are level.

II. Palpation: Check for any tenderness, tightness, rope-like tension, or inflammation in the paraspinous muscles or tenderness over bony prominences. This procedure checks for muscle spasms, vertebral fractures, or infection.

III. Range of Motion (ROM):

· Lumbar Flexion (normal is 90 degrees): This is the best measure of spine mobility. Restriction and pain during flexion are suggestive of herniation, osteoarthritis, or muscle spasm.

· Lumbar Extension (normal is 15 degrees): Pain with extension is suggestive of degenerative disease or spinal stenosis.

· Lateral Bending (normal is 45 degrees): Most patients should be able to touch the proximal fibular head of the knee. Pain on the same side as bending is suggestive of bone pathology, such as osteoarthritis or neural compression. Pain on the opposite side of bending is suggestive of a muscle strain.

· Rotation to the left and rotation to the right. Compare side to side.

· Range of motion may be varied due to the patient’s age and body habitus

IV. Gait: Ask the patient to walk on heels and toes. Expect normal gait, even with disc herniation.

· Difficulty with heel walk is associated with L5 disc herniation

· Difficulty with toe walk is associated with S1 disc herniation

V. Stoop Test: Have the patient go from a standing to squatting position.

In patients with central spinal stenosis, squatting will reduce the pain. However, asking the patient to run is not part of a back exam and may cause discomfort to the patient who is already in pain.

SITTING BACK EXAM

Dr. Lee performs a reflex test on Mr. Payne.

Dr. Lee walks through the steps for completing a neurologic exam in a patient with back pain.

Back Exam – Standing:

Mr. Payne has normal curvature, tenderness on palpation on the left lumbar paraspinous muscle with increased tone. Full range of motion, but has pain with movement. His gait is normal. He can walk on his heels and toes. He can do deep knee bends.

Back Exam – Seated:

Mr. Payne reports no pain when checked for CVA tenderness. He has no pain in his right leg with the modified version of SLR. While he does not exhibit a true tripod sign, he does complain of pain when his left leg is raised. Mr. Payne’s reflexes are 2+ and equal at the knees and 1+ at both ankles. The motor exam reveals 5/5 strength throughout the lower extremities. His sensory exam is normal.

Pulmonary Exam: His lungs are clear on auscultation and percussion.

Cardiovascular Exam: His cardiac exam demonstrates a regular rhythm, no murmur or gallop.

TEACHING POINT

Physical Exam for Back Pain—Seated Position

Overview of the Neurologic Exam

Deep Tendon Reflexes

Grading Reflexes:

0 No evidence of contraction

1+ Decreased, but still present (hyporeflexic)

2+ Normal

3+ Increased (hyperreflexia)

4+ Clonus: Repetitive shortening of the muscle after a single stimulation

Decreased patella reflex implies nerve impingement at the L3-L4 level. Decreased Achilles reflex implies nerve impingement of S1 levels. Hyperreflexia is a sign of upper motor neuron syndrome associated with spinal cord compression.

Muscle Strength

Rating Scale:

0/5 No movement

1/5 Barest flicker of movement of the muscle, though not enough to move the structure to which it’s attached

2/5 Voluntary movement, which is not sufficient to overcome the force of gravity. For example, the patient would be able to slide their hand across a table but not lift it from the surface.

3/5 Voluntary movement capable of overcoming gravity, but not any applied resistance. For example, the patient could raise their hand off a table, but not if any additional resistance were applied.

4/5 Voluntary movement capable of overcoming “some” resistance

5/5 Normal strength

i. Hip Flexion (L 2, 3, 4): Ask the patient to lift his thigh while you push down on his thigh

ii. Hip Abduction (L 4, 5, S1): Ask the patient to push his legs apart while you push them together

iii. Hip Adduction (L 2, 3, 4): Ask the patient to push his legs together while you push them apart

iv. Knee Extension (L 2, 3, 4):

Ask the patient to extend their knee while you push it down.

v. Knee Flexion (L 5, S1, S2):

Ask the patient to flex his knee while you push against it.

vi. Ankle Dorsiflexion (L 4, 5): Ask the patient to point his foot up while you push it down.

vii. Ankle Plantar Flexion (S 1, S 2): Ask the patient to point his foot down while you push it up.

Decreased strength implies nerve impingement of the associated nerve in parenthesis.

Sensation

Test for sharp and light touch along dermatomal distribution, great toe (L5), lateral malleolus, and posteriolateral foot (S1)

Nerve Root Impingement Syndromes

Nerve Root	Reflex	Pin-Prick Sensation	Motor Examination	Functional Test
L3	Patellar tendon reflex	Lateral thigh and medial femoral condyle	Extend quadriceps	Squat down and rise
L4	Patellar tendon reflex	Medial leg and medial ankle	Dorsiflex ankle	Walk on heels
L5	Medial hamstring	Lateral leg and dorsum of foot	Dorsiflex great toe	Walk on heels
S1	Achilles tendon reflex	Posterior calf, sole of foot, and lateral ankle	Stand on toes	Walk on toes (plantarflex ankle)

Check for costovertebral angle (CVA) tenderness, a sign suggesting pyelonephritis.

Modified version of the straight leg raise (SLR) test

While continuing to talk to the patient, raise each leg by extending the knee from 90 degrees to straight. If the pain is due to structural disease, the patient will instinctively exhibit the “tripod sign” by leaning backward and supporting himself with his outstretched arms on the exam table.

(The unmodified version of the straight leg raise (SLR) test is done in the next section of the exam with the patient supine.)

Neurological exam

Check reflexes, muscle strength, and sensation of the lower extremities. Focus on the L4, L5, and S1 nerve roots because most neuropathic back pain is due to impingement of these. Therefore, check the patellar reflex (L2-4) and Achilles reflex (S1). Check muscle strength for hip flexion, abduction, and adduction; knee extension and flexion; as well as ankle dorsiflexion and plantar flexion. Also, test for sharp and light touch along the dermatomal distribution of the great toe (L5), lateral malleolus, and posterolateral foot (S1).

SUPINE BACK EXAM

Dr. Lee begins the exam in the supine position.

Passive straight leg raise (SLR or Lasegue sign)

Faber Test: Flexion, abduction, and external rotation

Faber Test: Flexion, abduction, and external Rotation

Pelvic compression test

Dr. Lee continues, “The final part of the exam is done in the supine position.”

Dr. Lee begins the exam in the supine position.

Passive straight leg raise (SLR or Lasegue sign)

Faber Test: Flexion, abduction, and external rotation

Faber Test: Flexion, abduction, and external Rotation

Pelvic compression test

Dr. Lee continues, “The final part of the exam is done in the supine position.”

DIFFERENTIAL DIAGNOSIS AFTER EXAM

CLINICAL REASONING

Exam—Supine

Mr. Payne’s abdominal exam is negative. His straight leg raising is positive at 75 degrees on the left and negative on the right. His FABER test is negative and sacroiliac joint is non-tender.His motor exam reveals no weakness of the muscles of the lower extremities.

After finishing your exam together, you and Dr. Lee excuse yourselves from the exam room for a moment.

DISC HERNIATION

Symptoms of Disc Herniation

When disc herniation is suspected, a very important historical point is the position of comfort or worsening of symptoms.

Classically, disc herniation is associated with exacerbation when sitting or bending; and relief while lying or standing.

Other symptoms of disc herniation include:

· Increased pain with coughing and sneezing

· Pain radiating down the leg and sometimes the foot

· Paresthesias

· Muscle weakness, such as foot drop

· RED FLAGS

· CLINICAL REASONING

·

· Sciatica

·

Dr. Lee reminds you that disc herniation, a condition which is self-limited and usually resolves in two to four weeks, remains a working diagnosis for Mr. Payne. She says, “Let’s take a few minutes, though, to discuss some conditions we still don’t want to miss.”

Red Flags for Serious Underlying Causes of Back Pain

While the majority of back pain has a benign course and resolves within a month, a small number of cases are associated with serious underlying pathology. Timely treatment of these conditions is important to avoid serious consequences. Indications for early diagnostic testing such as x-rays and other imaging and referral are patients with progressive neurological deficits, patients not responding to conservative treatment, and patients with red flags signaling serious medical conditions such as fracture, cancer, infection, and cauda equina syndrome. Knowing this would also help guide the evaluation and treatment of back pain.

While the worst pain a patient has ever had is concerning and needs to be addressed, it is not by itself indicative of a more serious condition.

Numbness can be part of cauda equina, but is also common with a simple disc herniation, therefore by itself it is not a red flag.

Red Flags by Serious Condition

Cancer

1. History of cancer

2. Unexplained weight loss > 10 kg within 6 months

3. Age over 50 years or under 17 years old

4. Failure to improve with therapy

5. Pain persists for more than 4 to 6 weeks

6. Night pain or pain at rest

Infection

1. Persistent fever (temperature over 38 °C (100.4 °F))

2. History of intravenous drug abuse

3. Recent bacterial infection, particularly bacteremia (UTI, cellulitis, osteomyelitis, endocarditis, pneumonia, or pelvic inflammatory disease)

4. Immunocompromised states (chronic steroid use, diabetes, HIV, taking chemotherapeutic or biologic medications)

Cauda Equina Syndrome

1. Urinary incontinence or retention

2. Saddle anesthesia

3. Anal sphincter tone decreased or fecal incontinence

4. Bilateral lower extremity weakness or numbness

5. Progressive neurologic deficits

Significant Herniated Nucleus Pulposus

1. Major muscle weakness (strength 3 of 5 or less)

2. Foot drop

Vertebral Fracture

1. Prolonged use of corticosteroids

2. Mild trauma over age 50 years

3. Age greater than 70 years

4. History of osteoporosis

5. Recent significant trauma at any age (car accident, fall from substantial height)

6. Previous vertebral fracture

Mr. Payne does not have any red flags, so it is safe to wait to do any imaging or lab tests. Even with a disc herniation the pain often resolves on its own in six weeks, and no further workup is necessary.

DIAGNOSTIC TESTS

TESTING

While Dr. Lee takes the time to return to the exam room and review mechanical low back pain with Mr. Payne, she asks you to consider what other testing should be done at this time. Is an MRI indicated?

TEACHING POINT

Indications for Studies to Evaluate Low Back Pain

Laboratory tests generally are not needed in the evaluation of acute low back pain.

CBC

CBC, sedimentation rate (ESR), and C-reactive protein (CRP) should be ordered if tumor or infection is suspected.

X-ray

Agency for Health Care Policy and Research (AHCPR) guidelines for x-ray:

· History of trauma

· Strenuous lifting in patient with osteoporosis

· Prolonged steroid use

· Osteoporosis

· Age < 20 and > 70

· History of cancer

· Fever/chills/weight loss

· Pain worse when supine or severe at night

· Spinal fracture, tumor, or infection

The American College of Radiology (ACR) has appropriateness criteria for imaging for various conditions.  View the ones for low back pain  (.pdf).

Lumbar spine film

Lumbar spine films are commonly used, but lack specificity and have a high rate of false-positive findings. Patients with symptoms and pathology may have an apparently benign x-ray and asymptomatic patients may have abnormal x-rays.

MRI

An MRI is indicated if the following are present:

· Worsening or unremitting neurologic deficit or radiculopathy

· Progressive major motor weakness

· Cauda equina compression (sudden bowel/bladder disturbance)

· Suspected systemic disorder (metastatic or infectious disease)

· Failed six weeks of conservative care

However, 75% of herniated discs improve with six weeks of conservative therapy. MRI testing is not associated with clinical benefit in randomized trials. Early MRI is not associated with improved outcomes in patients with acute back pain or radiculopathy (Level 2/mid-level evidence). If surgery is being considered, some physicians recommend, in the absence of red flags, obtaining an imaging study after one month of symptoms.

Electrodiagnostics-Electromyography

Electrodiagnostics-Electromyography (EMG) and nerve conduction studies can be used in the evaluation of patients with radicular pain and lumbar spinal stenosis.

Electrodiagnostic tests are useful to confirm the existence of radiculopathy (level of nerve involvement) and to exclude the presence of other peripheral nerve disorders. Electrodiagnostic tests are time-sensitive because nerve root abnormalities may not be reliably detectable until three weeks after the onset of symptoms. They are particularly useful as an adjunct to clinical evaluation and imaging in the following two clinical scenarios: physical examination does not correlate with imaging studies, and to clarify the functional significance of an imaging abnormality.

Assessment of Acute Back Pain

In the absence of red flags or findings suggestive of systemic disease, diagnostic testing, especially imaging, is not indicated until after four to six weeks of conservative treatment. Ordering tests too early is not only cost-ineffective but can also cause harm to the patient.

Spine x-rays expose patients to radiation. This is particularly concerning in younger women because the radiation exposure to the ovaries in a single plain radiograph of the lumbar spine is equal to getting a daily chest x-ray (CXR) for approximately 75 days.

CT scans expose patients to contrast materials that have renal toxicity, and even higher doses of radiation. Routine imaging of the back using CT or MRI is not associated with improved outcomes and may identify abnormalities that are unrelated to the patient’s back pain. This can cause anxiety and could lead to more testing and possibly unnecessary intervention.

Algorithm for assessment of acute back pain .

You and Dr. Lee decide that it is not indicated to do imaging at this time for Mr. Payne

INITIAL TREATMENT

Conservative Therapy for Acute Low Back Pain

Conservative therapy for acute low back pain includes:

· Pharmacologic therapy: Aspirin/NSAID and/or muscle relaxants

· Local therapy:  Local therapy  (heat/cold). Learn more about local therapy  here .

· Activity: Advice to stay active or sending patient to physical therapy may help prevent recurrence.

Pharmacologic therapy: The first-line medications for the treatment of LBP are non-steroidal anti-inflammatory drugs (NSAIDs), acetaminophen, and muscle relaxants. Systematic reviews of randomized controlled studies found moderate evidence that NSAIDs and strong evidence that muscle relaxants are helpful in the treatment of acute LBP. The various NSAIDs and muscle relaxants are equally effective, while some muscle relaxants are more sedating. There is conflicting evidence about the superiority of NSAIDs to acetaminophen.

There is little evidence regarding the benefits of opioid use in LBP, and there is significant concern about the risk of the development of addiction. Occasionally, when pain cannot be controlled in other ways or when there are contraindications to other options, opioids are prescribed. Such prescriptions should be time-limited. No studies support the use of oral steroids in patients with LBP.

Learn more about activity  here  and  here .

Strict bed rest has not been shown to be beneficial. Patients should be encouraged to resume normal activities as soon as they are able to.

Referral to a surgeon or advanced imaging, such as MRI/CT scans, should be entertained if back pain is not better in four to six weeks or if progression of neurologic deficits is demonstrated. The  “Choosing Wisely” campaign in family medicine  has good patient resource material to explain the recommendation to wait for imaging.

PHYSICAL THERAPY

Effectiveness of Physical Therapy for Acute Back Pain

There is some data to show that tailored physical therapy is slightly more effective for acute back pain compared to patients who just stay active. At four weeks, patients who received physical therapy had 10-point improvement in a 100-point disability score compared to the control group. There is great variation in physical therapy because various interventions (exercises, traction, massage) and different modalities (heat, ice, ultrasound) may be used. There is also evidence that spinal manipulation is safe and can help in the short term.

PROGNOSIS

CARE DISCUSSION

You and Dr. Lee now return to Mr. Payne’s exam room to talk about treatment options with him. Dr. Lee tells Mr. Payne to avoid strenuous activities but to remain active. Dr. Lee increases the dosage of naproxen to 500 mg BID to take with food. Since his pain is intense (7/10), he is given a prescription for acetaminophen with codeine to take at night, when his pain is severe, and he is given a limited supply for seven days. Dr. Lee tells Mr. Payne about the side effects of both naproxen and codeine. Mr. Payne declines a muscle relaxant because they usually make him drowsy. He would like to be referred to physical therapy as it was helpful in the past.

Acute Low Back Pain Prognosis

Most cases of low back pain are acute in onset and resolution, with 90% resolving within one month and only 5% remain disabled longer than three months.

For patients who are out of work greater than six months, there is only 50% chance of them returning to work; this drops to almost zero chance if greater than two years.

Patients who are older (> 45) and patients who have psychosocial stress take longer to recover.

Recurrence rate for back pain is high at 35 to 75%.

Dr. Lee tells Mr. Payne that overall his prognosis is good. However, given his job as a truck driver and a history of LBP, he is likely to have a recurrence of his back pain. He should maintain good posture and practice good lifting techniques at all times. She gives him a booklet on back care and writes an order for the physical therapist to go over home exercises and show Mr. Payne appropriate lifting techniques.

Dr. Lee concludes by asking Mr. Payne to return for follow-up care in three to four weeks. She also gives him explicit instructions to call if there is no relief or if the pain increases.

PROGRESSION OF PAIN

Mr. Payne returns for a follow-up with increased back pain.

Three weeks later, Mr. Payne returns for his follow-up appointment and you discover the following:

Pertinent History

Mr. Payne has had little relief with the treatment prescribed. He is frustrated that he has been in pain for more than a month. His pain has been progressively worse. It radiates down the lateral part of his left leg and side of his left foot. This pain is worse than the back pain. He does not have any problems with bowel or bladder control and there is no weakness of his leg.