What is Sciatica? An Easy-to-Understand Explanation of Causes, Symptoms, and Treatment Approaches

Introduction

"It's sciatica."

Many people have likely had the experience of being told this at an orthopedic clinic.

However, in reality,

sciatica is not a disease name.

It is the name of a symptom.

Even students aiming to become physical therapists

• what sciatica is,

• how it differs from a hernia,

• and why pain occurs from the buttocks to the legs,

may sometimes be unable to explain these correctly.

In this article,

I will explain the mechanism, causes, symptoms, and key points for assessment of sciatica in an easy-to-understand way.

What is sciatica?

Sciatica refers to

pain or numbness

that occurs along the path of the sciatic nerve.

It is a symptom.

In other words,

Sciatica is not a disease name

but rather

a set of symptoms that occur in the sciatic nerve region

that is what it means.

What is the sciatic nerve?

The sciatic nerve is the thickest peripheral nerve in the human body.

It is formed by nerves emerging from the lumbar spine,

passes through the back of the buttocks,

the back of the thigh,

the calf,

and extends down to the foot.

Nerve pathway

L4

L5

S1

S2

S3

End of nerve pathway

↓

Sciatic nerve

↓

Tibial nerve

Common peroneal nerve

↓

Foot

Therefore,

even if the problem occurs in the lower back,

symptoms can appear all the way down to the foot.

Main symptoms

With sciatica,

buttock pain

thigh pain

calf numbness

and numbness in the toes may occur.

Patients often describe it as

• a feeling like an electric shock

• a tingling sensation

• Burning pain

• Heavy and dull

It is sometimes described as.

Why does sciatica occur?

It occurs when the sciatic nerve itself,

or the nerve root, is irritated.

1. Lumbar Disc Herniation

This is the most well-known cause.

The protruding disc compresses the nerve root.

It is relatively common in young to middle-aged people.

2. Spinal Stenosis

The pathway for the nerves becomes narrow,

and the nerves are compressed.

It is frequently seen in the elderly.

3. Lumbar Spondylolisthesis

Due to the displacement of the vertebrae,

stress on the nerves increases.

4. Piriformis Syndrome

This is a condition where the piriformis muscle,

located deep in the buttocks, compresses the sciatic nerve.

The difference between a herniated disc and sciatica

This is a frequently asked topic on national exams.

Lumbar disc herniation

Disease name

Sciatica

Symptom name

For example,

just as you get a cough from a cold,

you get sciatica from a herniated disc

is the general idea.

Why can it get worse when bending forward?

When a herniated disc is the cause,

bending forward increases the pressure inside the intervertebral disc.

Then,

the pressure on the nerve increases,

and the symptoms worsen.

Conversely,

with spinal canal stenosis,

bending forward can sometimes provide relief.

Impact on walking

When you have sciatica,

your walking pattern also changes.

Antalgic gait

Changing the way you walk to avoid pain

Reduced stride length

Unable to walk for long distances

Weight-bearing avoidance

Unable to put weight on the affected side

Decreased balance

Instability due to neurological symptoms

What do PTs evaluate?

Interview

• Site of pain

• Onset timing

• Aggravating factors

Neurological examination

• Sensation

• Muscle strength

• Deep tendon reflexes

SLR test

Representative nerve stretch tests

Gait observation

• Claudication

• Weight-bearing

• Stride length

Postural assessment

• Forward-leaning posture

• Lateral shift

• Pelvic alignment

Common clinical complaints

Patients may

"My legs hurt more than my lower back"

complain as follows.

Even in such cases,

the cause is often in the lower back.

Common complaints

• Cannot walk for long periods

• Numbness when sitting

• Pain when waking up in the morning

• Numbness extending to the toes

Things to consider as a PT

When evaluating sciatica,

it is important not to look only at the symptoms,

but to consider

why the nerve is being irritated.

Is it a herniated disc?

Is it spinal stenosis?

Is it spondylolisthesis?

Is it piriformis syndrome?

Evaluation and treatment change depending on the cause.

Summary

Sciatica is

a general term for pain and numbness that occurs along the path of the sciatic nerve.

It is a symptom name, not a disease name,

and its causes include

• lumbar disc herniation

• spinal canal stenosis

• lumbar spondylolisthesis

• piriformis syndrome

and so on.

As a PT,

rather than simply ending with "there is sciatica,"

it is important to identify the underlying cause.

By understanding the cause of the symptoms,

you can lead to more appropriate assessment and treatment.