Cauda equina syndrome
Definition
Acute loss of neurological function in the nerve roots below the end of the spinal cord (usually below about L1, L2).
Epidemiology
Essentially, many of the things that cause cauda equina syndrome are incredibly serious. The damage, if untreated, can become permanent.
Pathophysiology
For every cause, pressure is put on or direct damage is done to the nerves in the cauda equina.
- Tumour - this puts pressure on the cauda equina and is often a metastasis
- Trauma - direct damage to the nerves. Usually due to a prolapsed vertebral disc
- Spinal stenosis - due to a number of causes, the spinal canal becomes smaller, putting pressure on the nerves within
- Inflammation - things like Paget's disease of bone and ankylosing spondylitis get inflamed, putting pressure on the nerves.
Clinical Features
- Urinary and faecal incontinence - reduction in sphincter power
- Saddle anaesthesia (losing feeling in the bits of you that would touch a saddle - genitals, perineum, anus. That sort of area.)
- Lower motor neurone weakness - reduced power, tone and reflexes. Can lead to paralysis.
- Back pain and leg pain - radicular pain (along a dermatome) down legs
Conus medullaris syndrome
The conus medullaris is just above the cauda equina (T12-L1). Lesions here tend to cause urinary retention and constipation.
Investigations
- MRI and CT scans are done to accurately pinpoint nature and site of lesion. Occasionaly, urodynamics is done.
Management
Surgery, immediately in order to get out whatever it is that is causing the problem. If surgery is not possible, radiotherapy is the next option for tumours.
In connective tissue disorders, treat the connective tissue disorder.
Prognosis
The later the diagnosis and the greater the extent of the pain and neurological deficit, the worse the prognosis.