Does a history of lumbar spine surgery predict radiological cauda equina compression in patients undergoing MRI for suspected cauda equina syndrome?

Background

The clinical symptoms and signs of Cauda equina syndrome (CES) are non specific and poorly predictive of cauda equina compression on MRI. We aimed to establish whether a history of lumbar spine surgery predicts cauda equina compression on MRI in those presenting with suspected CES.

Methods

A retrospective electronic record review was undertaken of 276 patients referred with clinically suspected CES who underwent a lumbosacral spine MRI. Those with a history of prior lumbar surgery were compared to those without. The likelihood of cauda equina compression was compared between the two groups.

Results

About 78/276 (28%) patients with suspected CES had radiological compression of the cauda equina and went on to surgical decompression. A total of 54 (20%) patients had undergone prior lumbar surgery. Patients with a history of lumbar surgery were less likely to have cauda equina compression on MRI (χ2 - p  =  .035). Twenty six (9%) patients presented more than once with suspected CES. Patients with a history of lumbar surgery were more likely to re-present with suspected CES (χ2 - p = .002).

Conclusions

Prior lumbar surgery was associated with a higher frequency of re-presentation with clinically suspected CES but a lower frequency of radiological cauda equina compression.