Cite This Article

What is your diagnosis?

This is a case of subacute low back pain. Common causes include spondylopathy or arthritis, muscle spasm, lumbar disc pain, and radiculopathy. The lumbar XRs above are normal, and the above diagnoses typically do not have any findings on a plain film XR.

What are important elements to identify in the history?

Eliciting for “red flag symptoms” that would suggest an emergent cause of low back pain should always be the first step. These emergent conditions include cauda equina syndrome, spinal epidural abscess or hematoma, or other structural insufficiency leading to spinal cord compression. Symptoms of cauda equina syndrome include motor or sensory deficits, bowel or bladder incontinence, and saddle anesthesia. Additionally, one should ask about any other neurologic deficits, signs of infection (recent surgery, IVDU), chronic steroid use, recent trauma, and malignancy symptoms (weight loss, cancer history). 

For more common causes, identifying positional pain, radicular pain, and muscle spasms can also help narrow your differential. 

• Pearl: In evaluating for cauda equina with physical exam, rectal tone carries a sensitivity of 80%. Bulbocavernous reflex testing, while a very late sign, is close to 100% sensitive and specific [1]. 

What physical exam findings can help?

Physical exam can be particularly helpful in differentiating spondylopathy, radiculopathy, muscle spasm and disc inflammation. Start with both palpation of the paraspinal muscles (looking for asymmetry and firmness) and assess ROM. 

The straight leg raise test (Image 2A) and crossed straight leg test can be helpful for identifying radicular disc pain. For the straight leg raise test, the patient lays flat while the leg is raised to ~70 degrees with a dorsiflexed ankle, with ipsilateral pain at less than 60 degrees implying a positive test. However, reliability seems to drop off with more advanced age [2]. 

The stork test (Image 2B) is a common test for spondylopathy, and involves supporting the patient while they stand on one leg and assessing for pain while hyperextending the back. 

Image 2. Straight leg raise test (Left, 2A), and Stork test (Right, 2B). Author’s own images. 

When is it appropriate to obtain imaging?

Imaging is usually not indicated and is only helpful for patients with red flag symptoms (MRI with contrast), concern for trauma or fracture (CT non-contrast), or in those with greater than 6 weeks of symptoms despite treatment [3]. 

What is your management in the ED?

Fortunately, initial treatment for any of the non-emergent low back pain conditions is virtually the same. First line management is traditionally NSAIDs (barring any contraindications) [4]. Opiates, steroids, and muscle relaxants are also often used, but with higher risk side effect profiles. Importantly, multiple therapies have not been shown to be significantly better than monotherapies [5]. Other lower risk pharmacologic treatments include lidocaine patches and acetaminophen. 

Non-pharmacologic options to discuss with your patients include heat or ice therapy, physical therapy, massage, acupuncture, and traction, though results are varied [6]. It is also important to encourage mobility to prevent muscle stiffness. 

• Pearl: Acupuncture is increasingly being recognized as safe and effective for low-risk low back pain patients with some recent studies showing non-inferiority with pharmacologic management [7].

What is the typical course for patients presenting with this condition?

Most patients tend to have improvement to resolution within the first 1-2 months.

However, recurrence rates are often very high, particularly in patients with chronic pain and/or with high degree of functional impact, and those patients may benefit from additional referrals to physical therapy and/or orthopedic or spine surgery [8]. 

• Pearl: Patient education and expectation setting is also an important and often overlooked element to the treatment process. Providing home exercise handouts with basic low back exercises can give patients some autonomy with their care and jump start the rehabilitation process, especially if their symptoms persist and/or delays in accessing PT. These handouts are readily available for free via general internet searches or might be part of your institutional discharge summary handouts.