Definition of Sciatica

Sciatica is the pain circulating along the sciatic nerve. The sciatic nerve is the longest nerve in the body that extends from the lower back of the pelvis, through the hips, buttocks and the back of both legs, and down to the feet. The pain is triggered when the sciatic nerve is strained or compressed by something like a bone spur, a herniated disk, or a tumour. This usually affects only one side of the body. It produces inflammation and even numbness in the concerned leg.


Causes of Sciatica

There are various probable causes of Sciatica. Injury, infection, or any other condition that aggravates the sciatic nerve can trigger sciaticia. Here are some of the other common causes:

  • Herniated Disk
    Herniated disk or slipped disc happens when the soft cushion-like part of the disk positioned between the vertebrae of the spine slips through the fibrous external core and compresses the sciatic nerve root. The disks in between the vertebrae become weaker and are more prone to injury as you age.
  • Spinal Stenosis
    Spinal stenosis is the narrowing of the spinal canal that results to the compression of the sciatic nerve. This can be caused by the natural deterioration and aging of the vertebrae or the result of excessive growth of soft tissue or enlarged facet joints.
  • Isthmic Spondylolisthesis
    Isthmic Spondylolisthesis is a lumbar spinal condition that arises when there’s a small fracture or damage on the isthmus that lets one vertebral body to slip ahead on another vertebral body below it. This pinches the sciatic nerve. The isthmus, also known as the pars interarticularis, refers to the small section of the bone that links the facet joints at the back of the spine.
  • Piriformis Syndrome
    Piriformis syndrome occurs when the Piriformis muscle inside the buttocks contracts and triggers pain. Since the Piriformis muscle is located in the buttocks, it can put pressure on the sciatic nerve when Piriformis syndrome occurs.
  • Sacroiliitis
    Sacroiliitis is the swelling of the sacroiliac joint/s, which are located in the lower spine that is connected to the pelvis. This usually happens when you climb the stairs or stand for a long time, which causes sciatic-type pain in the lower back and down to the legs.
  • Spinal Tumours
    A spinal tumour situated in the spinal cord can cause sciatica as the tumour can irritate the sciatic nerve roots.


Symptoms of Sciatica

Sciatica usually shows symptoms that affect the buttocks and legs more than the back. It usually occurs abruptly and may last for a few days or weeks. Here are the possible symptoms of sciatica:

  1. Lower back pain from hip and buttocks down to one leg
  2. Numbness of the affected leg or foot
  3. Weakening of the calf muscles
  4. A tingling/burning sensation or a jolt from the lower back down to the leg or foot

The intensity of pain may vary from mild to severe. Sometimes, coughing, sneezing or long period of sitting may worsen the indications.


Risk Factors for Sciatica

Sciatica is mostly experienced by people who are between ages 30 to 50. Women who are pregnant are also prone to sciatica as the pregnancy puts pressure on the sciatic nerve when the uterus develops. Here are other risk factors for sciatica:

  • Aging – growth-related changes in the spine as you age, i.e. herniated disks and bone spurs
  • Obesity – additional body weight caused by obesity can increase the strain on the spine
  • Job – occupations that involve lifting of hefty loads, bending of the back, and other jobs that involve prolonged periods of sitting


Sciatica Prevention

Sciatica may recur even if you’ve had it in the past. The risk of sciatica may be reduced or prevented by the following:

  • Regular Exercise – exercises that help keep your back and core muscles strong. Make sure that you stretch before you exercise to avoid possible injuries. You can also ask your doctor for activities that are safe and effective in keeping your back sturdy.
  • Better Posture Adaptation – maintain a proper posture whenever you sit or stand. Make sure that you maintain the normal curve of your back to ensure proper posture.
  • Effective Body Mechanics Practice – when carrying heavy objects, make sure that you keep your back straight and bend your knees.


Sciatica Diagnosis

Sciatica can already be validated through the symptoms, but tests and diagnosis are needed in order to verify which treatment will alleviate the condition. Here are some of the ways on how to diagnose sciatica:

  • Physical Exam
    The doctor will usually ask where the pain occurs and when/how did it start. For the physical exam, the doctor may ask you to walk on your toes, stand from a squatting position, or even lift your leg in a straight position.
  • Imaging Tests
    Taking imaging tests is typically instructed when the pain is severe. These tests are used to determine the cause of sciatica, which will identify what treatment to take. The imaging tests may include MRI, Spine X-Ray, CT Scan and Electromyography (EMG).


Surgical Treatment for Sciatica

Most cases of sciatica pain are usually treated with non-surgical treatments. However, when the sciatica symptoms progressively become severe, it may require prompt surgical treatment. This depends on the patient’s decision.

There are different surgical treatments for sciatica, depending on the cause and extent of the sciatica pain:

  • Discectomy or Microdiscectomy
    If the cause of sciatica pain is due to herniated disk, the most suggested surgical treatment to be used is discectomy or microdiscectomy. Both procedures only remove the part of the herniated disk that is pressing the sciatic nerve, however microdiscectomy utilises microscopic magnification to perform a small incision.
  • Laminectomy
    If the sciatica pain is due to spinal stenosis, the surgical treatment that is most used is a laminectomy. This surgical procedure involves the removal of the lamina – a segment of the vertebrae, that is pushing the sciatic nerve.

Therapies may be recommended in order to improve the lower back muscles and promote faster recovery.


Dr Chua Soo Yong is an Orthopaedic and Specialist Spine Surgeon who is experienced in the management of sciatica.

Article Courtesy of Dr Chua Soo Yong
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