Approach to Low Back Pain & Cauda Equina Syndrome in the ED
Mnemonic for BACKPAIN Red Flags & Do Not Miss DDX =BACKPAIN can be CRAFTI
Back Pain Red Flags*
Bladder, Bowel & Erectile Dysfunction or Bilateral Sx**
Anaesthesia (saddle)
Cancer or Coagulopathy – Sx or PMH/risk (N.B. Thoracic Back Pain)
Kyphosis, stenosis, achondoplasia, or other pre-existingspinal narrowing.
Pain at Night +/-worse lying down think infection or cancer (USUALLY Discogenic pain is worse with flexion, & pain from spondylolysis is worse with extension)**
Age <20 or >50 = think harder about other causes.
IVDU/Immunocompromised/ recent Infection or Intervention(e.g. epidural), chronic steroids, sickle cell, organ failure, DM
Neurology (progressive & bilateral sensory or motor)**
*positive responses to “red flag’ questions for low backpain (e.g. bowel or bladder incontinence, history of cancer, trauma, fever, IV drug use etc) prompt further investigation, negative responses are not sufficient to rule out serious pathology.
** Retrospective tertiary centre review (U.K.) showed thatbilateral lower extremity pain, dermatomal distribution sensory loss, & loss of bilateral ankle/knee reflexes showed correlation with radiographic diagnosis of cauda equina compression (CEC); while digital rectal examination(DRE) did not demonstrate any benefit. However, individual symptoms showed poor performance in ruling in (or out) CEC. For more on low back pain emergencies see EM CASES Episode 26.
CRAFTI DDx of low back pain to consider:
Compression (CAUDA EQUNIA Compression [CEC], ConusMedullaris, Epidural Haematoma / Cauda Equina)
Renal Colic or other abdominal cause e.g. pancreatitis
AAA or vascular Dissection
Fracture (Trauma / Osteoporotic)
Tumour (cancer 1ary or 2ary)
Infection/Inflammation (Epidural Abscess, Osteomyelitis,Discitis, Transverse Myelitis)