Non-Traumatic Lower Back Pain

Most of us will have lower back pain in our lives (80–90% lifetime prevalence) and it accounts for 2–3% of ED visits (so quite a bit).

As with everything in EM, there are benign and serious causes and we need to differentiate between the two. The serious causes include diagnoses in the back and those in the abdomen or retroperitoneum.

  • Benign: muscular and ligament strain, sciatica (posterolateral disk herniation) and spinal stenosis
  • Serious back: cancer, spinal epidural abscess, vertebral osteomyelitis, infectious diskitis, spinal epidural hematoma and giant (central) disk hernation (cauda equina syndrome).
  • Serious non-back: AAA, renal stones, renal infarct, tumor, pancreatitis, pancreatic cancer, PUD, cholecystitis, retroperitoneal hemorrhage, psoas abscess

RED FLAGS FOR BACK PAIN

Be sure to document a good history and physical.

  • History
    • Epidural abscess: ***no fever, ***not immunocompromised, ***no IVDA, ***no known h/o bacteremia
    • Epidural tumor: ***no history of systemic cancer or weight loss
    • Epidural hematoma: ***no recent anticoagulation or recent spinal anesthesia
    • Fracture: ***not older age (> 55), ***no prolonged steroid use, ***no trauma, ***no abrasion/contusion to back
    • General: ***no new frequent falls or ataxia, ***no 3 wk of midline pain, ***no nocturnal pain, ***no sphincter incontinence or urinary urgency, ***no bilateral leg symptoms

 

  • Physical examination
    • Motor: ***no weakness in legs (or arms)
    • Sensory: ***no sensory level or saddle anesthesia
    • Reflexes: ***no diminished or hyperreflexic reflexes in the
      • knee
      • ankle
      • Babinski sign (abnormal/upward)
    • Sphincter dysfunction: ***no lax rectal tone (rectal optional but perform in intermediate or high risk patients)
    • Post void residual: ***no more than > 100 cc’s (if urinary symptoms)

 

Given the above, the patient would be classified as

  • HIGH RISK: Hx and PE red flags
  • MED RISK: Hx but no PE red flags
  • LOW RISK: no Hx or PE red flags

 

Testing

Lab testing is rarely useful. WBC, bands and percentage of neutrophils can all be normal in patients with spinal epidural abscess. Though ESR and CRP are non-specific, if normal they can help rule out infectious causes. Normal inflammatory markers don’t rule out disk herniation or epidural hematoma, though.

Imaging of the back should be carefully ordered. X-rays are of no value (if no trauma). MRI’s increased cost. Order these in high risk patients. You can get an outpatient MRI in medium risk patients (talk with the PMD, neurology or surgery to get follow-up, though).

If no further work up is required, discharge the patient home with pain medications and set their expectations.

Discharge Instructions for Low Back Strain

Provide proper instructions to patients who are sent home with lower back pain. First, they should have their expectations properly set. Second, more serious causes of back pain can present insidiously. The patient should know to return if things worsen.

You have been diagnosed with a lumbosacral back strain. This pain can often last 4–6 weeks, but should improve with proper care.

  • Application of heat can be minimally helpful (10 minutes on and 20 minutes off to prevent burns).
  • Bed rest should be of short duration (about 2 days) to hasten recovery.
  • Exercise is not recommended until your symptoms are completely better, but you should resume your normal daily activities.
  • Motrin 800 mg by mouth three-times a day with food for pain. You can take Norco for pain not relieved with Motrin. Muscle relaxants are helpful if there is a significant degree of spasm. These latter two medications can make you sleepy so avoid the use of heavy machinery, driving or complex decision making while on these medications.
  • It is very important you follow up with your primary care doctor in 1–2 weeks.
  • While our most likely suspicion for the cause of your back pain is a lumbosacral strain, more serious causes can initially present similarly. Therefore, return immediately if you develop any of the following symptoms:
    • Numbness or weakness or arms or legs
    • Increasing pain
    • Inability to go to the bathroom normally
    • Numbness in the perineum (“the crotch”)

 

Serious causes of back pain

Spinal Epidural Abscess (SEA)

This has been increasing in incidence due to more diabetes, IVDA, immunosuppressants and invasive spinal procedures. The traditional triad (back pain + fever + neurologic symptoms) is, of course, often absent. The most common finding is severe, unrelenting back pain. If they have such severe pain and a risk factor, you should really consider SEA and order an MRI of the entire spine with and without gadolinium.

Treatment usually consists of antibiotics and surgical decompression, but in those without neurologic symptoms some considering waiting on surgery. Let the surgeon make that call. Consult the neurosurgeon, regardless.

Epidural Tumors

Again the presenting symptoms is unrelenting back pain. Look also for weakness and UMNL (hyperreflexia – probably best to check the knee and ankle). By the time you get bowel and bladder dysfunction, it is too late. Sometimes they don’t have a known primary tumor and this is the first presentation of the cancer. The tumor often presents in any part of the spine.

  • Thoracic 60%
  • Lumbosacral 30%
  • Cervical 10%

The primary sources are from lung, breast and multiple myeloma. But non-Hodgkins lymphoma often presents with extramural spinal cord compression, as well.

Treatment is chemotherapy, radiation and surgery. Call the oncologist and surgeon. Steroids can also be used, so discuss with the consultants.

Spinal Epidural Hematoma

The main risk factors are a recent spinal instrumentation (though in one study, none of the OB epidurals caused a SEH) or use of anti-coagulants in a patient with back pain. Sometimes a venous hemorrhage can occur from an increase in abdominal or thoracic pressure resulting in an spontaneous SEH in the anti-coagulated patient.

Patients present with severe back or neck pain, radiculopathy and neurologic symptoms.

They will likely need surgical decompression and most likely anti-coagulant reversal. Call the neurosurgeon!

Giant Lumbar Disk Herniation

Central disk herniation (33%–75% antero-posterior hernation) is different from sciatica (smaller postero-lateral herniation) and results in cauda equina syndrome. This can be provoked by minimal trauma (like twisting, heavy labor) or the trauma may be absent.

Indications for surgery include cauda equina syndrome, progressive motor deficits or intolerable symptoms.

References

  • Singleton J, Edlow J. “Acute Nontraumatic Back Pain Risk Stratification, Emergency Department Management, and Review of Serious Pathologies.” EM Clinics of North America. 2016
Non-Traumatic Lower Back Pain

Discharge Instructions

The October edition of EM-RAP had a great section on how to write good discharge instructions. This is not the pre-printed stuff that comes with the EMR but instructions written specifically for each patient. I modified my DCI (discharge instruction macro) to make those points more obvious.

 
You have been diagnosed with ***, this is ***. Your evaluation in the emergency deparmtent was significant for ***.

1. FOLLOW-UP: Please see your primary doctor within a week. If you do not have a primary doctor, call the number above to arrange to establish a relationship with a doctor. Your condition may change and so it is important to have your condition re-assessed. 
2. RETURN IF: Please return immediately if you get worse, if you don't get better, if your symptoms change, if you have any new or concerning symptoms. If your symptoms change, then we need to reassess potential causes. 
3. MEDICATIONS: You have been prescribed ***. Take the medicines as described in the instructions provided by teh pharmacy. In taking this medicine, you should note ***.

It is also useful to build some specific macros for things that come up often (e.g., more than once). For example, for Levaquin.

the antibiotic LEVAQUIN is associated with tendon rupture in some patients. Please rest from strenous activity while on this medication. If you have questions, ask your doctor or pharmacist.

Or for narcotic medications.

the pain killer NORCO has an opioid mixed with Tylenol. The opioid can make you drowsy, even to the point of stopping breathing. Do not opeate heavy machinery, drive or perform any potentially dangerous tasks while on this medicine. Also do not take it with other sedating substances like alcohol or even Benadryl. The medicine also contains Tylenol, so do not take any othe Tylenol containing products while on this medication. You can run the risk of severe liver damage. If you have questions, ask your doctor or pharmacist.

I also make a practice of talking to every patient before they leave to explain the instructions. I dont typically document that conversation, but it is a good habit. Include the following in the ED COURSE SUMMARY macro.

Additional discharge verbal instructions were given and discussed with the patient. Patient had the opportunity to ask questions and these were answered.
Discharge Instructions

Brief Resolved Unexplained Events (BRUE)

ALTE has been deprecated and replaced with BRUE. Apparent Life-Threatening Events scared parents and led physicians to unnecessary testing. The American Academy of Pediatrics has issued the following guideline.

BRUE
====

STEP 1: Meets DEFINITION of BRUE
- BRIEF: less than 1 minute episode  
- RESOLVED: back to baseline/normal  
- UNEXPLAINED: no other etiology (no URI, vomiting, etc) 
- EVENT:
     - cyanosis or pallor (not erythema)
     - absent, decreased or irregular breathing
     - marked change in tone 
     - altered level of responsiveness  
- in a normal child, less than 1 year old 

STEP 2: Stratify as LOW risk  
- more than 60 days old 
- full term (gestational age more than 32w)
- 1st event and not in clusters
- less than 1 minute
- no CPR by *trained medical provider* 
- no concerning features on H&P

STEP 3: Consider TREATMENT options for LOW risk
- SHOULD DO: educate care giver, shared medical decision making regarding can-do items, CPR training for parents
- CAN DO: pertussis testing, ekg, serial observation, pulse oximetry
- DONT HAVE TO DO: admit, viral PCR, glucose, HCO3, lactate, Hgb, CT head (unless judgement says differently), UA
- SHOULD NOT DO: WBC, CSF, Cx, BMP, urine organic acids, CXR, echo, EEG, GERD tests, H2 blockers, anti-epileptics, no home monitoring

HIGH risk patients consider 
- abuse
- cardiac arrhythmias (family history of sudden death)
- infection (URI Sx)
- others guided by context
  1. Tieder JS, Bonkowsky JL, Etzel RA, Franklin WH, Gremse DA, Herman B, Katz ES, Krilov LR, Merritt JL 2nd, Norlin C, Percelay J, Sapién RE, Shiffman RN, Smith MB; SUBCOMMITTEE ON APPARENT LIFE THREATENING EVENTS. Brief Resolved Unexplained Events (Formerly Apparent Life-Threatening Events) and Evaluation of Lower-Risk Infants: Executive Summary. Pediatrics. 2016 May;137(5). https://www.ncbi.nlm.nih.gov/pubmed/27244836
Brief Resolved Unexplained Events (BRUE)

HEART Score

Used to risk stratify patients for further cardiac workup in the ER according to risk of major adverse cardiac events (MACE).

History	
2: highly suspicious
1: moderately suspicious
0: slightly or non-suspicious

ECG	
2: significant ST-depression
1: non-specific repolarization
0: normal

Age	
2: > 65 years old
1: 45-65 years old
0: < 45 years old

Risk Factors (DM, recent smoker <1m, HTN, HLP, fam Hx, obesity)	
2: 3+ risk factors (or prior CAD)
1: 1-2 risk factors
0: none

Troponin	
2: 3x normal limit
1: 1-3x normal limit
0: < normal limit 

LOW: 0-3 → 1.7% to 2.5% MACE over next 6 weeks (discharge home) 
MED: 4-6 → 16.6% to 20.3% MACE over next 6 weeks (observation) 
HIGH: 7-10 → 50.1% to 72.7% MACE over next 6 weeks (early invasive strategies)

According to University of Maryland Shared Decision Making program for low risk chest pain, additional ECG and troponin testing can decrease low risk group to approximately 1.7% MACE. Stress testing brings it down to 1%.
  1. Backus BE, Six AJ, Kelder JH. Risk scores for patients with chest pain: evaluation in the emergency department. Current cardiology …. 2011.
  2. Backus BE, Six AJ, Kelder JC, et al. A prospective validation of the HEART score for chest pain patients at the emergency department. Int J Cardiol. 2013;168(3):2153-2158. doi:10.1016/j.ijcard.2013.01.255.
  3. Six AJ, Backus BE, Kelder JC. Chest pain in the emergency room: value of the HEART score. Neth Heart J. 2008;16(6):191-196.
HEART Score