Cauda Equina Syndrome

Definition/diagnostic criteria Cauda Equina Syndrome (CES) is a severe neurological condition involving compression of the cauda equina nerves at the base of the spinal cord. It is characterised by lower back pain, sciatica, sensory deficits in the saddle area, bladder and bowel dysfunction, and lower extremity motor weakness or sensory loss. Diagnostic criteria include these clinical features in conjunction with radiological evidence of cauda equina compression.

Epidemiology CES is a rare disorder, with an estimated UK incidence of 1 in 33,000 to 100,000. It can occur at any age, but most commonly affects individuals aged between 30-60 years. There is no significant gender predilection.

Diagnosis
Clinical features:

• Early symptoms may include severe lower back pain and unilateral or bilateral sciatica.
• Urinary symptoms range from difficulty initiating micturition or impaired sensation of urinary flow through to retention or incontinence.
• Bowel dysfunction, typically presenting as incontinence or altered sensation during defecation, is also common.
• Saddle anaesthesia and lower extremity motor or sensory deficits may also be present.

Investigations: Magnetic Resonance Imaging (MRI) is the investigation of choice for confirming CES, revealing the extent and site of compression. Typical abnormalities include herniated discs, tumours or lesions compressing the cauda equina. In cases where MRI is contraindicated, CT myelography can be considered.

Treatment Early surgical decompression is the mainstay of treatment for CES. The timing of surgery is crucial; ideally, decompression should occur within 48 hours of symptom onset to maximise recovery potential. Postoperative management includes pain relief, physiotherapy, and addressing urinary and bowel dysfunction.

Medications for neuropathic pain, such as pregabalin or gabapentin, may be required. Long-term management often requires a multidisciplinary approach including physiotherapy, pain management, and psychological support.

Prognosis The prognosis of CES varies, depending heavily on the time to decompression and the severity of symptoms at presentation. Early intervention, especially within 48 hours, is associated with a better outcome. However, some degree of permanent neurological deficit is common. Chronic pain, as well as bladder and bowel dysfunction can persist, significantly impacting quality of life.