What Causes Sciatica?

By Ehren Allen, DPT/Certified Orthopedic Manual Therapist

What Causes Sciatica?

A commonly asked question is what causes sciatica. Sciatica is a general term to describe pain radiating down the leg. The pain can come from several sources but they are all related to the Sciatic nerve. The sciatic nerve is a large nerve that begins in the low back travels down the back of the thigh. At the knee, the Sciatic nerve splits into smaller branches and then goes into many of the muscles of the lower leg.

The quick answer is Sciatica pain can originate at several points along the nerve. These may include:

  • Lumbar disk
  • Lumbar facet joint
  • Piriformis muscle
  • Sacroiliac joints

The Lumbar Disk

The most common source of Sciatica pain is the lumbar disk. The lumbar disk can become irritated and inflamed. Inflammation in the disk can cause pain down the sciatic nerve, even if the nerve is not actually compressed. This is because the disk itself has nerve endings which come from the branches of the sciatic nerve.

What causes sciatic nerve pain

Pinched human sciatic nerve

Facet Joints

The facet joints are the small joints in the spine which  allow movement in the spine.  There are 2 facet joints at every spine level (one on each side).  The facet joints also have nerve endings which come from the branches of the sciatic nerve.  Irritation or inflammation in the facet can cause pain down the sciatic nerve in the leg.

The Piriformis Muscle

The Piriformis muscle is a muscle in the pelvis near the gluteal muscles.  The sciatic nerve passes very close to the piriformis muscle as it descends through the pelvis.  Sometime, tightness in the piriformis muscle can apply pressure to the sciatic nerve.  This may cause sciatica pain.  True piriformis problems are not that common. The piriformis is often blamed because of its proximity to the pain, but it is usually not the actual cause.

What causes sciatica at JOI.

Piriformis Syndrome and Anatomy

Sacroiliac Joints

The Sacroiliac joints (SIJ) are the large joints that connect the lower spine to the pelvis. The SI joints have a lot of nerve endings which carry pain information. They can cause a lot of pain when they have a dysfunction. The Si joints are very stable though and true SI issues are not as common as lumbar disk issues. SI joint issues are more common during and after pregnancy or with severe trauma to the pelvis.

How Do You Fix Sciatica?

It is important to determine what causes sciatica to treat it properly.  The quick answer is early physical therapy is usually to best first step. A physical therapist will perform a detailed evaluation and help to identify to source of the pain. Treatment may include manual therapy and exercises to improve movement and decrease the stress on painful area.

In some cases, advanced tests such as X-rays or MRIs may be needed if the pain does not improve. These tests can help physicians know whether medical treatments may help

Click to learn more about sciatica neuralgia.

The Jacksonville Orthopedic Institute has the area’s top spine doctors and physical therapists.  The JOI team can help you find the answer to Sciatica!  To schedule an appointment, call JOI-2000 or click the link below.  To learn more about sciatic nerve stretches, please go to: Sciatic Nerve Stretches.

Book an Appointment with The Jacksonville Orthopaedic Institute Today!

JOI Physicians continue to offer online new patient appointments. This is another option to make it more convenient to make new patient appointments with less phone hold times. Follow the link below to select your JOI MD and schedule online.

You can still call 904-JOI-2000 to make new patient JOI Physician Appointments if that is your preference.

To make appointments with JOI Rehab, please call 904-858-7045.

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