What is the recommended management for a patient with unilateral left-sided radiculopathy and new onset urinary retention?

Management of Unilateral Radiculopathy with Urinary Retention

Urgent MRI and neurosurgical consultation are required immediately as this presentation suggests cauda equina syndrome, which is a surgical emergency requiring prompt decompression.

Clinical Assessment and Diagnosis

The presentation of unilateral left-sided radiculopathy with urinary retention represents a concerning clinical picture that warrants immediate attention:

• While the radiculopathy is unilateral, the presence of urinary retention is a critical red flag that suggests cauda equina compression
• This combination represents what is classified as Cauda Equina Syndrome with Incomplete symptoms (CESI), where there is objective evidence of cauda equina compression with retention of urine 1
• CESI is considered a true surgical emergency that requires immediate intervention to prevent progression to complete cauda equina syndrome with retention (CESR), which has worse outcomes 1, 2

Immediate Management Steps

1. Obtain emergency MRI of the lumbar spine without contrast

   • MRI is the imaging study of choice for suspected cauda equina syndrome 1
   • Should be performed immediately, regardless of time of day 3
   • A single 3-D heavily T2-weighted fat-saturated sequence protocol can be used for rapid assessment in emergency settings 1

2. Urgent neurosurgical consultation

   • Contact neurosurgical service immediately while MRI is being arranged
   • Do not delay referral waiting for complete urinary retention or bilateral symptoms 1, 2

3. Bladder management

   • If not already done, insert urinary catheter to relieve retention
   • Document post-void residual volume
   • Note that catheterization prior to complete assessment can mask progression of symptoms 1

Surgical Considerations

• Timing of surgery: Emergency decompression should be performed as soon as practically possible, by day or night 2
• Surgical approach: Directed at the level of pathology causing cauda equina compression, typically via decompressive laminectomy and discectomy 4
• Outcomes: Better outcomes are associated with earlier surgical intervention before progression to complete cauda equina syndrome 1, 5

Important Clinical Considerations

• The presence of urinary retention with unilateral radiculopathy should never be dismissed as a simple disc herniation 6
• Clinical signs alone are not reliable for diagnosing or excluding cauda equina syndrome - MRI is essential 3, 6
• Even though the radiculopathy is unilateral, the urinary symptoms indicate potential bilateral nerve root involvement at the cauda equina level 1
• Delaying surgical intervention can lead to irreversible neurological damage and poor long-term bladder, bowel, and sexual function 1, 2

Common Pitfalls to Avoid

1. Waiting for bilateral symptoms - Unilateral radiculopathy with urinary symptoms is sufficient to warrant emergency evaluation 1, 2
2. Delaying MRI - Imaging should be performed immediately, not deferred to regular working hours 3
3. Attributing urinary symptoms to other causes - In the context of radiculopathy, urinary retention should be presumed to be neurogenic until proven otherwise 1
4. Relying solely on clinical examination - The sensitivity and specificity of clinical findings for cauda equina syndrome are poor; MRI is required 6

Remember that cauda equina syndrome exists on a spectrum, and early intervention before complete syndrome development offers the best chance for recovery of neurological function 7.