Lower Back Pain: Medical Student Clinical Pearl
Grace Dao, CC4
MD Candidate
Class of 2021
Case Presentation
Mr. Payne Bach is a 54 yo male who presents to the emergency department via EMS with lower back pain.
He reports that he hurt his back this afternoon when he was picking up a heavy, antique chair. Immediately, he felt something “give out” in his back and reports a sharp 10/10 central lower back pain that radiates unilaterally to the left side. It did not radiate down his legs. He was unable to ambulate due to the pain and called EMS.
He received 975 mg Acetaminophen in the ambulance which did not alleviate his pain. Mr. Bach reports that before picking up the chair he was feeling well. He denies any history of back pain or activities of back overuse. He denies any history of trauma or injury to his back recently or in the past. In the emergency department he reports his pain remains at 10/10 and cannot sit up or move in bed due to the pain.
He denies any change in sensation or pain to his legs. He denies any change in sensation to his perineum or any bowel incontinence. He has not urinated since the incident. Incidentally when reviewing a past medical history he reports an unintentional weight loss of 15 lbs in the last 2 months. He denies any history of a prior cancer diagnosis. On review of systems he denies history of cough, fevers, night sweats, hematochezia or gross hematuria. Mr. Bach has a 20 pack year smoking history.
Mr. Bach had difficulty with the physical exam due to pain. He appeared very distressed. All vital signs were within normal limits. An order for IV opiods was ordered and he was reassessed 30 minutes later.
Physical exam
Inspection: there were no obvious deformities of the back, no scarring or bruising or abrasions. Mr. Bach continued to look uncomfortable but was no longer in any acute distress.
Palpation: Mr. Bach was tender to palpation over L4-5. There was tenderness to palpation of the paraspinal muscles at the same level.
ROM: Mr. Bach was very hesitant to move, thus, it was difficult to assess his range of motion.
Neuro: Reflexes at the knee and ankle were normal. Babinski was negative. Normal sensation throughout all dermatomes. 5/5 strength on flexion/extension at the hip, knee and ankle.
Special tests: Straight leg raise and Lasegue’s test were negative.
Back Pain
Back pain is an extremely common condition. It is estimated that 70-85% of people will experience back pain at some point in their life1. A recent study out of an emergency department in Halifax, found that 3.17% of patients presented with to the emergency department with a complaint of lower back pain2. Back pain is within the top 5 reasons for primary care visits3. The differential diagnosis for lower back pain ranges from mechanical lower back pain to critical conditions that need to be recognized 4. Due to its prevalence and potentially sinister causes it is important to have an evidence-based approach to lower back pain.
To Image or Not to Image-That is the Question
Choosing Wisely Canada has put out recommendations for both Family and Emergency physicians with regards to low back pain. For family medicine the recommendation is “don’t do imaging for lower-back pain unless red flags are present” 5. It has been found that imagining those without red flags before 6 weeks does not improve outcomes.5
Similarly, for emergency medicine the recommendation is “don’t order lumbosacral (low back) spinal imaging in patients with non-traumatic low back pain who have no red flags/pathologic indicators.”6
Red flags 6:
| Cauda Equina Syndrome |
| Severe worsening pain, especially at night |
| Significant trauma |
| Weight loss |
| History of Cancer |
| Fever |
| Night sweats |
| Steroid use |
| IV drug use |
| First episode of back pain in age > 50, especially concerning if age > 65 |
| Widespread neurological signs (loss of sensation, loss of motor function, loss of reflexes in the legs) |
It is also important to remember that not all red flags are created equal and to include clinical judgement in the decision making process.8 A systematic review examining the predictive value of commonly assessed red flags found that for fracture older age, prolonged steroid use, severe trauma, and contusion/abrasion increased the probability of fracture to 10-33%, and if multiple red flags are present fracture risk increases to 42-90%.
When considering red flags that increase risk of malignancy, previous history of malignancy increased risk 7-33%; while older age, unexplained weight loss, and failure to improve after one month all were found to have post-test probabilities of less than 3% when predicting malignancy risk8.
Back to our case
Mr. Bach has red flags for both fracture and malignancy:
| Severe, worsening pain |
| Age > 50 |
| Weight loss |
XRs of the lumbar spine were ordered and indicated several compression fractures, with one area suspicious for a metastatic lesion. Follow CT spine was ordered and confirmed metastatic disease. Mr. Bach was admitted to hospital for pain control, physiotherapy and a malignancy work up.
References
1. Andersson, G. B. (1999). Epidemiological features of chronic low-back pain. Lancet 354(9178):581-585. doi:10.1016/S0140-6736(99)01312-4
2. Edwards, J., Hayden, J., Asbridge, M., & Magee, K. (2018). The prevalence of low back pain in the emergency department: A descriptive study set in the Charles V. Keating Emergency and Trauma Centre, Halifax, Nova Scotia, Canada. BMC Musculoskeletal Disorders, 19(1), 306. https://doi.org/10.1186/s12891-018-2237-x
3. Finley, C. R., Chan, D. S., Garrison, S., Korownyk, C., Kolber, M. R., Campbell, S., Eurich, D. T., Lindblad, A. J., Vandermeer, B., & Allan, G. M. (2018). What are the most common conditions in primary care? Systematic review. Canadian family physician Medecin de famille canadien, 64(11), 832–840.
4. Patel, A.T., & Ogle, A.A. (2000). Diagnosis and management of acute low back pain. Am Fam Physician 61(6):1779-1790.
5. College of Family Physicians of Canada. Choosing Wisely Canada. Thirteen Things Physicians and Patients should question. July, 2019. Retrieved from: https://choosingwiselycanada.org/family-medicine/
6. Canadian Association of Emergency Physicians. Choosing Wisely Canada. Ten things Physicians and Patients Should Question. July, 2019. Retreived from: https://choosingwiselycanada.org/emergency-medicine/
7. Toward Optimized Practice (TOP). (2011). Guideline for the evidence-informed primary care Management of Low Back Pain. Retrieved from: https://portal.cfpc.ca/resourcesdocs/uploadedFiles/Directories/Committees_List/Low_Back_Pain_Guidelines_Oct19.pdf
8. Downie, A., Williams, C. M., Henschke, N., Hancock, M. J., Ostelo, R. W. J. G., de Vet, H. C. W., Macaskill, P., Irwig, L., van Tulder, M. W., Koes, B. W., & Maher, C. G. (2013). Red flags to screen for malignancy and fracture in patients with low back pain: Systematic review. BMJ, 347.
Copyedited by Dr. Mandy Peach
