Common Back Pain Red Flags

Is your back pain a sign of a serious disease?

Back pain is very common—four out of five people experience back pain at some point in their lives. But there are times when it's a signal something serious could be going on with your health. 

Some of the most serious conditions that can lead to back pain include spinal infection, cancer, and a problem known as cauda equina syndrome, in which compressed nerve roots cut off sensation and movement.

Some symptoms that occur alongside back pain are warnings, or “red flags,” that may indicate to your healthcare provider you have a underlying medical condition. Recognizing these red flags may help lead the way to a timely diagnosis and treatment. 

Below are a few of the most common red flags healthcare providers generally check for during a medical evaluation.

The back pain red flags listed below may indicate a serious medical condition, or they may be unrelated to your back pain. Only a healthcare provider will be able to tell the difference, so it's important to bring any symptoms you have to your healthcare provider's attention.

Back Pain Red Flag Signs and Symptoms

  • Age (being younger than 18 or older than 50)
  • Fever or chills
  • Recent illness or surgery
  • Trauma
  • History of cancer
  • Unexplained weight loss
  • Night pain or pain at rest
  • Incontinence
  • Saddle anesthesia (loss of feeling in the buttocks and inner thighs)
  • Weak, numb, or painful leg muscles

Some red flags may occur together to indicate an underlying condition. Fever, chills, and recent illness may point to a spinal infection, for example. Signs of cancer include unexplained weight loss and experiencing pain at night or at rest. Incontinence, numbness or weakness in the legs, and loss of feeling in the buttocks and inner thighs are red flags that show up in cauda equina syndrome.

Back pain red flags may indicate other medical conditions beyond infection and cancer.


Doctors preparing patient for MRI scan
Morsa Images / Getty Images

If you are younger than 18 or older than 50, acute back pain may be cause for concern. Back pain in people younger than 18 without a history of trauma may indicate a stress fracture in a vertebra. Gymnasts, weight lifters, and other athletes who experience repeated stress to the lower back are susceptible to this kind of injury.

If you are experiencing severe pain, especially at night, or you recently lost weight without trying, or if your pain gets worse when you lie on your back, these red flags may be a sign of a spinal tumor or cancer, especially in those younger than 18.

If you are older than 50, new back pain may signal a number of potential conditions, including a tumor or spinal infection. New back pain may also indicate something as common as kidney stones or as serious as an abdominal aortic aneurysm, a life-threatening weakness in the major vessel that supplies blood to your legs.

If your healthcare provider expresses concern about cancer at your appointment, they may refer you to another specialist for further testing. 

Fever, Chills, or Recent Illness or Surgery

Stiff neck

JGI / Tom Grill / Blend Images / Getty Images

A fever may indicate an infection, such as meningitis, infection in the​ epidural space around your spinal cord, or surgery-related infection.

Common symptoms of spinal infection include, but are not limited to, fever, chills, stiff neck, and/or unexplained weight loss.

Fever, chills, or recent illness with low back pain may be a sign of a spinal epidural abscess, an infection between the outer covering of the spinal cord or nerve roots and the bones surrounding it.

Spinal epidural abscesses can occur in people who have boils, infections in the bloodstream or bones of the spine, and those who have recently had back surgery. People who use intravenous drugs are also at increased risk for spinal epidural abscess.

If you are an IV drug user, have a compromised immune system (from HIV, steroid use, or a transplant), and/or have had a urinary infection, you may be at higher risk for a spinal infection.

A recent lumbar puncture during surgery or an epidural injection to help with back pain, for example, can also increase risk of an infection or epidural hematoma (pooling of blood on the outer covering of the brain or spinal cord and nerve roots).

With a spinal infection, it is imperative to get an accurate diagnosis as quickly as you can.

Treatment focuses on eliminating the infection, relieving pain, improving nutrition, maintaining spinal stability, and preserving and restoring the functioning of your nervous system.


Fractured vertabrae illustration

John Bavosi / Getty Images

Major trauma, such as a bad car accident, significant fall, or sports injury, may result in a fracture of the spine. A vertebral fracture may additionally injure surrounding nerves or the spinal cord itself.

However, even minor trauma can be cause for concern, particularly if you are older than 50 or have (or are at risk for) osteopenia, osteoporosis, cancer, or another condition that weakens the bones. Reaching, twisting, or falling from standing height are examples of minor trauma that may damage the spine.  

If you are using anticoagulant medication, trauma can also result in an epidural hematoma. If this is the case, you may have back pain, weakness, or tingling in your arms or legs.

History of Cancer

If you currently have cancer or have had cancer in the past, back pain may indicate a recurrence or metastasis, where the cancer has spread to other parts of the body.

Back pain that worsens over several months, unexplained weight loss, and pain at night or at rest may also indicate cancer.

Some types of cancers are especially likely to put pressure on the spine. Spinal cord compression is a common complication of prostate, breast, and lung cancers. Patients with metastatic bone cancer may also develop epidural spinal compression.

Night Pain or Pain at Rest

Experiencing back pain at night or at rest can be—but isn't necessarily—a sign of a serious condition such as an infection or cancer.

This is particularly true if your night or resting back pain occurs alongside another symptom. For example, pain at night and recent weight loss, especially in adolescents, are red flags for cancer and warrant a visit to your healthcare provider.

Incontinence and Saddle Anesthesia

The nerves of the lower back / Getty Images

Soiling yourself without realizing it, numbness in your groin or inner thigh, or both may be signs of nerve problems, including cauda equina syndrome.

In this syndrome, compressed nerve roots in the lumbar spine cut off sensation and movement in the buttocks and inner thighs (known as saddle anesthesia). Loss of feeling and paralysis can become permanent without quick treatment.

Cauda equina syndrome can result in serious damage to your health—including paralysis. As such, symptoms of cauda equina warrant immediate medical attention.

When accompanied by new and severe back pain, saddle anesthesia is often associated with cauda equina syndrome.

Other common symptoms of cauda equina include being unable to empty your bladder completely, increased frequency of urination, and overflow incontinence.

Patients with this condition also frequently report sexual dysfunction and leg weakness or sciatica, especially if these symptoms are severe or keep getting worse.

Weak, Numb, or Painful Leg Muscles

Your healthcare provider may test the strength of both your legs, particularly if your back pain came on suddenly and you are experiencing nerve pain. Weakness in your legs may indicate spinal cord or nerve root compression.

If you experience back pain often and the strength of your lower limbs has become weaker, it may be a sign of neurological damage.

A Word From Verywell

Lower Back, Lumbar Pain
Universal Images Group / Getty Images

Back pain and the red flags mentioned here can indicate a serious underlying medical condition. Let your healthcare provider know if you are experiencing any of these symptoms.

It's best to speak with your healthcare provider about any findings, even if the screening was performed by your physical therapist, personal trainer, or holistic practitioner. 

Your healthcare provider will be able to tell you whether your symptoms are related to another medical condition and help you treat and manage your back pain.

10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. Cleveland Clinic. Lower back pain causes & treatment.

  3. Orthoinfo - American Academy of Orthopaedic Surgeons. Spondylolysis and spondylolisthesis.

  4. McDevitt L, Davis MA. Recognizing the red flags of low back pain. Nursing Critical Care. 2011;6(1):24-29. doi:10.1097/01.CCN.0000390625.88962.e5

  5. MedlinePlus Medical Encyclopedia. Abdominal aortic aneurysm.

  6. American Association of Neurological Surgeons. Spinal infections.

  7. MedlinePlus Medical Encyclopedia. Epidural abscess.

  8. MedlinePlus Medical Encyclopedia. Epidural hematoma.

  9. Downie A, Williams CM, Henschke N, et al. Red flags to screen for malignancy and fracture in patients with low back pain: systematic review. BMJ. 2013;347(dec11 1):f7095-f7095. doi:10.1136/bmj.f7095 

  10. American Association of Neurological Surgeons. Cauda equina syndrome.

Additional Reading

By Anne Asher, CPT
Anne Asher, ACE-certified personal trainer, health coach, and orthopedic exercise specialist, is a back and neck pain expert.