The Importance of Undertaking Emergency Scans in Suspected Cauda Equina Syndrome


In this clinical risk alert, THEMIS’s Lead Clinical Partner, TMLEP, highlights the importance of recognising the cauda equina red flags.

A Case Example

In a case recently reviewed by TMLEP, the patient exhibited to their GP with a history of chronic back pain dating back several years. The patient was suffering a severe flare-up of the back pain that was radiating down both legs. Pain and spasm continued for two weeks, at which point they developed numbness and urinary incontinence.

The patient was admitted to hospital and established to have over 200ml of urine in the bladder. The attending clinician acknowledged the request for an MRI from the GP visit but documented that an urgent MRI was not indicated. The patient suffered a fall the same day whilst in hospital and was unable to move their foot normally afterwards. The patient received an MRI scan two days later. The day after, the MRI scan was reviewed and reported as showing severe spinal stenosis. At this stage, the patient was referred to neurosurgery with a diagnosis of cauda equina syndrome.

Post-operatively, the patient continues to suffer with sphincter damage and foot drop as a result of the delay in performing the MRI and it being acted upon, as by the time they were taken to surgery, the damage caused by the cauda equina compression was irreversible.

The main learning points from this review stem from the following events:

  • Inconsistent and conflicting documentation of facts between GP and hospital,

  • Lack of documentation on whether the bladder scan was taken pre- or post-void,

  • Delay of around five days in performing the MRI scan,

  • Delay in obtaining the MRI report. In this case, given the red flag symptoms for cauda equina syndrome the patient had presented with, a delay of 24 hours was significant lost time in treating them.

Independant Recommendations to Prevent Incident Recurrence and Improve Patient Safety

TMLEP’s recommendations to reduce recurrence and enhance patient safety are as follows:

  • Ensure documentation from previous examinations for the same condition are reviewed in context with a new examination. This is to ensure accurate and efficient communication of information, which not only expedites the patient getting the correct treatment, but also reduces the risk of an incorrect diagnosis being reached when clinical symptoms are incorrectly or insufficiently recorded.

  • Document whether bladder scans are taken pre- or post-void. If a scan shows urine is still present in the bladder, it is vital to know whether the patient has urinated prior to this, as an incomplete emptying of the bladder is an indicator for development of cauda equina syndrome.

  • Ensure same day MRI scans are taken in cases of suspected cauda equina syndrome. CES develops very quickly and as such, any delay in obtaining scans to reach a diagnosis can have severe and permanent consequences to the patient, given a delay in diagnosis will lead to a delay in treatment.

  • Ensure MRI reports are obtained urgently in cases of suspected CES. A delay of 24 hours in this case resulted in a delay in the patient being taken to surgery and therefore they had the surgery approximately 96 hours after onset of CES.

  • Perform surgery within 48 hours of onset of CES to give the patient the maximum chance of an optimal outcome with no permanent symptoms. If the surgery in this case had been performed within this timeframe, the foot drop and sphincter damage the patient suffered would have been avoided.


In summary, this case surrounds the delay in undertaking an MRI scan in a patient with red flag signs of cauda equina syndrome. This delay, and subsequent delay in reporting the MRI, resulted in surgery being performed outside of the critical 48-hour timeframe after onset of cauda equina and therefore lead to the patient suffering irreversible symptoms.

TMLEP would like to highlight the importance of identifying these red flag symptoms and undertaking an emergency scan to confirm a diagnosis of cauda equina syndrome to reduce the risk of permanent symptoms developing.