When the Nerves Stop Talking: How Neurological Injury Can Affect Bladder and Bowel Control

Going to the toilet feels automatic. In reality, it depends on an extraordinarily complicated conversation between the brain, spinal cord, nerves, muscles, bladder and bowel.

Most of us don't think of going to the toilet as a neurological function.

You feel that you need a wee.

You find a toilet.

You go.

Your bowel works in much the same apparently unremarkable way.

So when somebody develops difficulty controlling or emptying their bladder or bowel, it can be tempting to assume that the problem must lie in those organs themselves.

But there is another rather important participant in all of this:

the nervous system.

Going to the toilet depends upon an extraordinarily complicated series of messages travelling between the brain, spinal cord, peripheral nerves and the muscles and organs of the pelvis.

Interrupt those messages and something as ordinary as having a wee or opening your bowels can change dramatically.

Your bladder doesn't work alone

The bladder has two jobs that sound deceptively simple.

Store urine.

And, at an appropriate moment, empty it.

But doing that successfully requires coordination.

As the bladder fills, information about that filling travels through the nervous system.

The brain has to receive and interpret those signals. It then helps decide whether this is an appropriate time and place to urinate.

When it is time to go, the bladder muscle and urinary sphincter need to behave in a coordinated way so that urine can leave.

NICE describes lower urinary tract function as the coordinated storage and expulsion of urine regulated by the central and peripheral nervous systems.

Which means a bladder problem can sometimes begin somewhere quite a long way from the bladder.

What happens when those messages are disrupted?

That depends enormously on where the neurological damage occurs and which pathways are affected.

There isn't one universal thing called a “neurological bladder”.

One person may experience overwhelming urgency.

Another may lose some of the sensation telling them that their bladder is full.

Someone else may be unable to empty their bladder properly.

Some people experience urinary incontinence.

Others develop urinary retention.

And some can experience combinations of these symptoms.

Specialist uro-neurology services therefore see people with conditions as varied as multiple sclerosis, Parkinson's disease, spinal cord and brain tumours, cauda equina injuries and other traumatic neurological disorders.

NICE also lists stroke, head injury, spinal cord injury and peripheral nerve injury among neurological problems that can affect lower urinary tract function.

The important point is this:

Loss of bladder control doesn't necessarily mean a bladder has “failed”.

Sometimes the communication system controlling it has been damaged.

And the bowel?

Here we encounter much the same problem.

Successful bowel function also requires sensation, movement, sphincter control, pelvic floor coordination and intact neurological signalling.

Damage to those systems can produce neurogenic bowel dysfunction.

Again, that doesn't look the same for everybody.

It can involve constipation.

Difficulty emptying the bowel.

Reduced sensation.

Urgency.

Loss of bowel control.

Or a bowel routine that takes considerably more active management than it once did.

The Royal National Orthopaedic Hospital explains that spinal cord injury can cause neurogenic bowel and that the precise pattern depends upon the level and completeness of the injury. Management may involve an individualised bowel programme incorporating medication, timing, diet, rectal stimulation or manual techniques.

For some people, therefore, “going to the toilet” stops being something spontaneous.

It becomes something that has to be managed.

What about brain injuries?

It isn't only damage to the spinal cord or peripheral nerves that can affect bladder and bowel control.

Brain injuries can too. 

The brain forms part of the complex neurological system responsible for controlling bladder and bowel function, and an acquired brain injury can disrupt the messages travelling between the brain, bladder and bowel.

Headway describes a range of possible consequences, including urgency, increased frequency, difficulty emptying the bladder or bowel, reduced awareness that they are full, and loss of bladder or bowel control.

There can also be another layer to the problem.

Brain injury may affect mobility, cognition and communication, meaning that somebody might struggle to recognise or communicate that they need the toilet, plan what they need to do, or reach one in time.  

Similarly, bladder and bowel problems are recognised following stroke, another form of acquired brain injury, and the Stroke Association notes that problems controlling the bladder and/or bowel are common after a stroke.

In other words, a change in continence following a brain injury isn't necessarily simply a practical consequence of reduced mobility. The neurological systems involved in controlling the bladder and bowel may themselves have been affected.

For readers who want to know more, Headway's guide to continence problems after brain injury is an excellent accessible resource, and the Stroke Association's bladder and bowel information provides further information specifically about stroke.

Bladder and bowel problems often travel together

This is something I think deserves much more public understanding.

Medicine frequently divides the body into specialties.

Urology looks after one system.

Gastroenterology or colorectal services another.

Neurology another.

But nerves aren't particularly interested in hospital departmental boundaries.

NICE notes that because the neurological centres involved in urinary, bowel and sexual function are anatomically close, people with neurological disease can experience a combination of bladder, bowel and sexual dysfunction.

That can happen with an acquired injury such as spinal cord or cauda equina injury, but neurological bladder and bowel dysfunction can also occur in progressive conditions.

Multiple sclerosis is a particularly good example. The MS Society reports that up to 7 in 10 people with MS may experience a bowel problem at some stage, including constipation or loss of bowel control.

This isn't an obscure side effect of neurological disease.

For many people, it's a substantial part of living with it.

The part of neurological disability we don't see

When we picture neurological injury, we tend to picture the things that are visible.

A wheelchair.

A walking stick.

Difficulty moving a limb.

Perhaps tremor or problems with balance.

But some of the consequences of neurological injury are hidden beneath clothing and behind bathroom doors.

Bladder dysfunction.

Bowel dysfunction.

Sexual dysfunction.

And because we don't see them, it's very easy to underestimate their impact.

Someone who looks perfectly composed may also be calculating when they next need to catheterise.

Another person may structure their morning around a bowel-management programme.

Somebody may need medication, irrigation, catheters, pads or other equipment simply to manage functions most of us never have to consciously organise.

And sometimes these aren't minor inconveniences.

For some people with spinal cord injury, disruption to bladder or bowel function can trigger autonomic dysreflexia, a potentially life-threatening rise in blood pressure. NHS England specifically identifies bowel care as a potential trigger in people at risk.

So when we talk about neurological disability, bladder and bowel function belong in that conversation too.

Some well-known people have talked about this

One person I think would work particularly well here is broadcaster and disability campaigner Sophie Morgan.

Sophie sustained a complete thoracic spinal cord injury in a car accident when she was 18. In interviews, Sophie has spoken candidly about the consequences of paralysis that aren't necessarily visible on television — including incontinence, sexual dysfunction, UTIs, chronic pain and difficulties regulating body temperature.

That is powerful precisely because it challenges the simplified idea that spinal cord injury means only being unable to walk.

It doesn't.

A spinal cord injury can alter numerous functions below the level of injury.

And bladder and bowel control can be among them.

Sometimes the biggest loss is spontaneity

There's another consequence that's difficult to capture in medical terminology.

Most people don't have to plan how they're going to empty their bladder.

They don't have to think about whether they have the equipment necessary to do it.

They don't need a bowel programme.

They don't need to consider whether a toilet will allow enough time or space for what they need to do.

When neurological damage changes these functions, some of that unconscious spontaneity can disappear.

And the impact can extend far beyond the bathroom.

It can affect work.

Travel.

Relationships.

Sex.

Sleep.

Socialising.

Confidence.

Independence.

And how safe someone feels being away from home.

The clinical words “neurogenic bladder” and “neurogenic bowel” are relatively small phrases for something that can occupy an enormous amount of a person's life.

Why are we talking about this during Urology Awareness Month?

Because urology isn't only about diseases that originate in the urinary tract.

Sometimes a urinary problem begins with the nervous system.

And recognising that matters.

It matters for diagnosis.

It matters for treatment.

It matters for research.

And it matters for the people whose symptoms may otherwise be misunderstood as simply a “weak bladder”, constipation or an embarrassing continence problem.

At Oui, we keep returning to the same idea:

our bodies don't divide themselves neatly into medical specialties.

The bladder talks to the brain.

The bowel talks to the spinal cord.

The pelvic organs depend upon nerves.

And when those conversations are interrupted, the consequences can be profound.

Perhaps talking about those consequences shouldn't be quite so difficult either.

Oui. Together, we can.

A note from Oui

Oui provides awareness and health information, not individual clinical advice. Neurological bladder and bowel symptoms can have many causes and require individual assessment. New loss of bladder or bowel control — particularly alongside new numbness around the genitals or bottom, leg weakness or severe back pain — can require urgent medical assessment.

For reliable information, NICE's guidance on urinary dysfunction in neurological disease is particularly useful, while the Royal National Orthopaedic Hospital's information on neurogenic bowel explains how spinal cord injury can affect bowel function.