“They Said It Was Just Back Pain”: Delayed Diagnosis of Cauda Equina Syndrome

Spinal and neurosurgical negligence · 13 min read · First published March 2026 · Updated November 2026 · Next review May 2027

By Dr Rosemary Listing, PhD (Law) · Medical negligence specialist, in practice since 2014 · Of Counsel, Peter Evans & Associates

If this is close to what happened to you, you may be living with consequences that are hard to talk about: catheters, accidents, numbness, pain, changes to sex and relationships, losing work. You may also be carrying a question nobody has answered: would it have been different if they had moved faster?

That is a fair question, and it is often the central one. This guide is part of our section on spinal and neurosurgical negligence and our guide to missed and delayed diagnosis.

Start with your question

• What is cauda equina syndrome?
• What are the red flag symptoms?
• How quickly should I have had an MRI?
• Does the timing of surgery really matter?
• Where do delays usually happen?
• Is a delayed diagnosis negligence?

What cauda equina syndrome is

The spinal cord ends around the top of the lower back. Below that, the nerves carry on down the spinal canal as a loose bundle that looks a little like a horse's tail, which is what “cauda equina” means. These nerves supply the legs, the bladder, the bowel, sexual function, and feeling in the “saddle” area: the bottom, genitals and inner thighs.

Cauda equina syndrome (CES) happens when those nerves are squeezed. The most common cause is a large disc prolapse in the lower back. Less commonly it is caused by narrowing of the spinal canal, a bleed or infection in the spine, a tumour, an injury, or a complication of spinal surgery.¹

It is rare. Estimates suggest between 1 in 33,000 and 1 in 100,000 people a year,¹ which is one reason it gets missed: most GPs and emergency doctors see a great deal of back pain and very little CES.

The red flags

Back pain on its own is very common and usually gets better. What changes the picture is back or leg pain together with any of these, especially if they are new:²³

• Saddle numbness: reduced feeling around the bottom, genitals or inner thighs, often first noticed when wiping.
• Bladder changes: difficulty starting to pass urine, a weak stream, not feeling urine pass, not being able to go, or leaking.
• Bowel changes: not feeling a bowel motion, constipation that is new, or loss of control.
• Sciatica in both legs, or sciatica that spreads from one leg to both.
• Weakness or numbness in the legs that is severe or getting worse.
• Sexual changes: new numbness or loss of function.

You don't need every sign. Clinicians are taught not to wait for the full set before acting, because by then the damage may be done.

What should happen when red flags appear

Australia's Low Back Pain Clinical Care Standard, published by the Australian Commission on Safety and Quality in Health Care, says that suspected cauda equina syndrome needs emergency assessment or referral, and that emergency departments should immediately refer suspected cauda equina compression for urgent imaging and surgical review.² It also says people with back pain should be reassessed at later visits for new concerning features.

In practice, that usually means a careful history (including direct questions about the bladder, bowel and saddle sensation), an examination of leg strength, reflexes and sensation, and a check of how much urine is left in the bladder after trying to go. It also means safety-netting: clear advice, ideally written down, to come straight back if red flag symptoms appear.

How quickly the MRI should happen

MRI is the scan that confirms or rules out compression. Many people sent for an urgent scan turn out not to have CES, and that is how it should work: scanning a lot of people to catch the few who do is the price of not missing it.

Australia doesn't have a single national time target for the scan. In England, the national pathway published in 2023 says that people with suspected CES should have an emergency MRI as soon as possible, and certainly within four hours of the request, and that surgery should follow on an emergency basis if compression is found.⁴ It isn't binding here, but it is a useful marker of what specialists now consider reasonable, and expert witnesses may refer to it.

The common failures are not usually about the scan itself. They are about the hours around it: a referral that wasn't made, an overnight wait for a scanner, a result that sat unread, or a transfer to a spinal unit that took too long.

Why the timing of surgery matters

Clinicians often describe two stages:¹

• Incomplete CES (CES-I): the bladder is affected (for example, reduced sensation or difficulty starting) but still works.
• CES with retention (CES-R): the bladder has stopped emptying, and the person can't pass urine or is leaking because it is overfull.

The research consistently shows that the state of the bladder at the time of surgery matters most: people operated on while still at the incomplete stage generally do better than people who have already reached retention.¹³⁵ One UK study of people with incomplete CES found that about 16% of those operated on within 48 hours had bladder problems at follow-up, compared with 56% of those operated on after 48 hours.⁶

The evidence on exact timing is genuinely mixed. A large UK study of more than 600 people found no clear link between time to surgery and outcome once severity was taken into account, while finding that people who already needed a catheter before surgery were far more likely to still need one afterwards.³ That is why, in a legal case, the question is less “how many hours?” and more “what stage were you at when you should have been treated, and what stage were you at when you were?”

The “48-hour rule” you may have read about is not a safe window. An Australian review concluded there is no strong basis for 48 hours as a blanket safe time to delay surgery, and that earlier decompression is likely to be better for compressed nerves, especially when symptoms are getting worse.⁵ The aim is to stop someone with incomplete CES from deteriorating to retention while they are in the system.¹

Where delays usually happen

In the UK, where this has been studied closely, about 23% of litigated claims about spinal surgery relate to CES, and delayed diagnosis is the most common complaint.⁴

The records that tell the story

In CES cases, the timeline is everything. These are the documents that usually show it:

You are entitled to ask for your own health records. A short written request to each provider is usually enough.

How the law looks at it

A bad outcome from CES is not, on its own, negligence. Sometimes CES develops very quickly, or is already at the retention stage when the person first arrives, and nothing anyone did would have changed the result. In a delayed diagnosis case, the questions are more specific.

Was the care below the accepted standard? The question is whether the doctor, nurse or physiotherapist acted in a way that was widely accepted by peer professional opinion as competent practice at the time (section 5O of the Civil Liability Act 2002 (NSW)).⁷ Missing red flags that were present, failing to ask about them, failing to examine, or failing to arrange an urgent scan when CES was suspected are the usual issues. National guidance like the Clinical Care Standard can help show what accepted practice looks like.

Did the delay cause harm? This is usually the hardest part. It has to be shown that, on the balance of probabilities, earlier action would have led to a better outcome (section 5D).⁸ A lost chance on its own isn't enough (Tabet v Gett).⁹ In practice, the evidence often turns on the CES-I and CES-R distinction: if you were still at the incomplete stage when you should have been scanned and operated on, and reached retention during the delay, that can be powerful evidence.

Who can claim, and when

The person who was harmed can claim. In NSW, time usually runs from when you knew, or ought to have known, enough to claim, not simply from the date of surgery. See time limits in NSW or other states, our guide to how a claim works, and what compensation can cover. Because CES can affect work, relationships and care needs for life, these claims can be significant.

In my practice

In the CES files I see, the failure is rarely one dramatic mistake. It is a series of small ones: a GP note that says “back pain, analgesia” with nothing about the bladder; a phone call where new numbness was reported and the advice was to wait; an emergency department note that says “no red flags” without recording that anyone checked; an MRI requested at 9pm and done at 2pm the next day. Lining up those times, hour by hour, is often where the answers are.

Both things can be true

The doctors you saw may have been busy, kind and doing their best, and the system may still have let you down. You may be grateful for the surgery, and still angry about the hours before it. Both are allowed.

The bigger picture

CES claims are among the most common in spinal care, and they keep recurring for the same reasons: red flags not asked about, and scans not available when they are needed. You can check a practitioner's registration on the Ahpra public register, and complaints about care in NSW can go to the Health Care Complaints Commission. Our page on complaint or claim explains the difference.

Support

• Lifeline, 24-hour crisis support: 13 11 14
• Beyond Blue, anxiety and depression support: 1300 22 4636
• Continence Health Australia, National Continence Helpline: 1800 33 00 66
• healthdirect, 24-hour nurse advice: 1800 022 222

If your symptoms were brushed off as stress, our article on neurological symptoms dismissed as anxiety may also help.

The woman in the story keeps a folder now: every appointment, every phone call, every time. It started because nobody else seemed to be keeping track. Now it's how she makes sure she's heard.

With care,
Rosemary

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