Several spinal cord problems may cause typical sciatica signs and symptoms, and while rare, these conditions may cause paralysis or become life-threatening if not treated immediately.
The following are a few examples of spinal-cord-related serious medical conditions that may cause typical sciatica symptoms, highlighting several differentiating symptoms.
In This Article:
- When Sciatica Pain Is a Medical Emergency
- Spinal Cord Conditions with Sciatica Symptoms
- Spinal Tumors and Sciatica Symptoms
- Blood Vessel Conditions Causing Sciatica Symptoms
- Sciatica Causes and Symptoms Video
Cauda Equina Syndrome
This syndrome is caused by the compression of the cauda equina, a group of nerves at the bottom of the spine. The cauda equina extends over part of the lower lumbar spine and the sacrum (triangle-shaped bone at the bottom of the spine). A primary symptom of cauda equina syndrome is sharp, stabbing pain in the legs as in sciatica. 1 Gardner A, Gardner E, Morley T. Cauda equina syndrome: a review of the current clinical and medico-legal position. Eur Spine J. 2010;20(5):690–697. doi:10.1007/s00586-010-1668-3
A few differentiating signs and symptoms include some combination of:
- Severe low back pain
- Severe weakness and numbness in the legs making it difficult to stand or walk
- Numbness, tingling, and/or weakness in the groin, genital, and/or anal region
- Partial or complete loss of bowel and/or bladder control or retention of urine
- Sexual dysfunction (often due to numbness in the perineal area)
Cauda equina syndrome may progress suddenly. It is important to treat this syndrome as soon as possible to prevent paralysis of the lower body.
Spinal Epidural Abscess

Abscesses containing fluid or pus can collect in the epidural space and cause sciatica-like symptoms.
A spinal epidural abscess is the collection of pus in the epidural space. This abscess may develop as a result of cells that are carried through the blood from other locations, such as skin or urinary tract infections. The abscess compresses the spinal cord, causing sciatica-like symptoms, usually in both legs. 2 Alerhand S, Wood S, Long B, Koyfman A. The time-sensitive challenge of diagnosing spinal epidural abscess in the emergency department. Internal and Emergency Medicine. 2017;12(8):1179-1183. doi:10.1007/s11739-017-1718-5
Apart from low back pain with radiating pain in the legs, other signs and symptoms of a spinal epidural abscess may include:
- Fever
- Increased pain when lying down or gently pressing the lower back
- Loss of bladder control
Epidural abscess pain typically worsens with time. The abscess may become larger and spread to other areas if left untreated. Patients with immune deficiency, diabetes, and intravenous drug use may be at an increased risk for spinal epidural abscesses.
Hemorrhagic Lumbar Synovial Cyst

Facet joint degeneration may lead to the formation of hemorrhagic lumbar synovial cysts.
A lumbar synovial cyst is a fluid-filled cavity that usually develops from degenerated facet joints and compresses the spinal cord. They usually develop from abnormal motion within a vertebral segment. In most cases, these cysts are not a medical emergency and may be treated non-surgically. However, if bleeding occurs into the cyst, it is called a hemorrhagic lumbar synovial cyst and is considered a medical emergency.
A hemorrhagic lumbar synovial cyst may cause acute, intolerable pain, numbness, and/or tingling in the lower back and legs, similar to sciatica. If sciatica symptoms become acute or severe, it is advised to visit a doctor. 3 Park HS, Sim HB, Kwon SC, Park JB. Hemorrhagic lumbar synovial cyst. J Korean Neurosurg Soc. 2012;52(6):567–569. doi:10.3340/jkns.2012.52.6.567 , 4 Cicuendez M, Alen JF, Ramos A, Lobato RD, Lagares A. Spontaneous hemorrhage into a lumbar synovial cyst. Eur Spine J. 2010;19 Suppl 2(Suppl 2):S190–S192. doi:10.1007/s00586-010-1332-y
See Synovial Cyst Symptoms and Diagnosis
The above list is not comprehensive; anyone with severe or concerning sciatica signs and symptoms is advised to consult a doctor.

What is sciatica?
Sciatica is a set of symptoms that occurs when nerve roots between L4 to S3 on either side of the lower spine become irritated or pinched.
Sciatica symptoms originate in the lower back, radiate deep into the buttock, and travel down the leg.
Sciatica occurs due to an underlying medical condition; it is not a medical diagnosis.
What are the common causes of sciatica?
Lower back conditions that may cause sciatica include:
- Lumbar Herniated Disc
- Spondylolisthesis
- Degenerated Disc Disease
What are the common symptoms of sciatica?
- PAIN. Sciatica pain may be constant or intermittent and is usually described as a burning sensation or a sharp, shooting pain that extends from the lower back into the buttock, leg, and possibly the foot.
- ALTERED SENSATION. Numbness, tingling, and/or a pins-and-needles sensation may be felt at the back of the leg.
- WEAKNESS. Weakness may be felt in the leg and foot. A feeling of heaviness in the affected leg may make it difficult to lift the foot off the floor.
How is sciatica treated?
Nonsurgical Treatments
While treating sciatica, it is essential to obtain an accurate diagnosis of the underlying cause, since the treatment of each condition may be unique and different from the others.
Nonsurgical methods are typically tried first and may include one or a combination of the following:
- Physical Therapy
- Massage
- Lumbar Therapeutic Injections
- Medication
- Manual Therapy
Surgical Treatments
Surgery may be indicated when progressive neurological deficits occur.
- Microdiscectomy
- Lumbar Decompression
This information is not intended or implied as a substitute for medical advice, diagnosis or treatment. All content, including text, graphics, images or other information provided is intended for general information purposes only. Always consult with your physician for diagnosis or treatment.
- 1 Gardner A, Gardner E, Morley T. Cauda equina syndrome: a review of the current clinical and medico-legal position. Eur Spine J. 2010;20(5):690–697. doi:10.1007/s00586-010-1668-3
- 2 Alerhand S, Wood S, Long B, Koyfman A. The time-sensitive challenge of diagnosing spinal epidural abscess in the emergency department. Internal and Emergency Medicine. 2017;12(8):1179-1183. doi:10.1007/s11739-017-1718-5
- 3 Park HS, Sim HB, Kwon SC, Park JB. Hemorrhagic lumbar synovial cyst. J Korean Neurosurg Soc. 2012;52(6):567–569. doi:10.3340/jkns.2012.52.6.567
- 4 Cicuendez M, Alen JF, Ramos A, Lobato RD, Lagares A. Spontaneous hemorrhage into a lumbar synovial cyst. Eur Spine J. 2010;19 Suppl 2(Suppl 2):S190–S192. doi:10.1007/s00586-010-1332-y