What is Sciatica?
What is Sciatica?
Sciatica is a term used to describe symptoms caused by irritation or compression of the sciatic nerve, rather than a diagnosis in itself. It typically presents as pain, altered sensation, or discomfort that travels from the lower back into the buttock and down the leg.
The sciatic nerve is the largest and longest nerve in the body. It plays a key role in connecting the lower spine to the muscles and skin of the leg and foot. Because of its length and pathway, it can be affected at several points, which is why symptoms can vary widely between individuals.
Sciatica most commonly affects one side of the body, although the severity, location, and nature of symptoms can differ depending on the underlying cause.
Understanding the Sciatic Nerve
The sciatic nerve is formed from several nerve roots that exit the lumbar spine (lower back) and sacrum (base of the spine). These nerve roots join together and travel through the pelvis, passing deep beneath the gluteal muscles before continuing down the back of the thigh and into the lower leg and foot.
Along its course, the nerve can be influenced by spinal structures, surrounding joints, and soft tissues. This is why both spinal and non-spinal factors can contribute to sciatic symptoms.
What Sciatica Can Feel Like
The presentation of sciatica can vary significantly from person to person. Common descriptions include:
A sharp, shooting pain that travels down the leg
Burning or electric shock-like sensations
Aching or deep discomfort in the lower back or buttock
Tingling or pins and needles in the leg or foot
Numbness in certain areas of the lower limb
In some cases, weakness in the affected leg
Symptoms may be constant or intermittent. Some people notice their symptoms worsen with prolonged sitting, bending forwards, coughing, or certain movements of the spine or hip.
Common Causes and Contributing Factors
Sciatica occurs when there is irritation or pressure placed on the nerve roots or the sciatic nerve itself. This can happen for several reasons, and often there is more than one contributing factor.
1. Disc-related changes
One of the most common causes is irritation from a lumbar intervertebral disc. This may involve a bulge or herniation, where the disc material places pressure on nearby nerve roots.
2. Degenerative (wear and tear) changes
Age-related changes in the spine can lead to reduced space around the nerves. This may include joint thickening or changes in spinal alignment.
3. Spinal stenosis
This refers to a narrowing of the spaces within the spine, which can place pressure on the nerves, particularly during standing or walking.
4. Muscular and soft tissue irritation
In some cases, the nerve may be irritated by deep gluteal muscles, particularly in the hip region. This can mimic or contribute to sciatic-type symptoms.
5. Load and movement-related factors
Repetitive strain, prolonged sitting, sudden increases in activity, or reduced movement variability can all influence symptoms.
How Sciatica is Assessed
Assessment of sciatica focuses on identifying the likely source of nerve irritation and understanding how it behaves in response to movement and load.
A clinical assessment may include:
Detailed symptom history (onset, behaviour, aggravating and easing factors)
Postural and movement analysis
Lumbar spine and hip range of motion testing
Neurological testing (strength, reflexes, sensation)
Functional movement assessment (e.g. sitting, bending, walking tolerance)
The goal is not only to identify what is sensitive, but also to understand what positions or movements influence symptoms.
Management Principles
Most cases of sciatica improve over time with conservative management. The approach is typically based on the underlying cause and the individual’s presentation.
Movement and activity
Prolonged rest is generally not recommended. Instead, guided movement that keeps the body active without repeatedly aggravating symptoms is usually encouraged.
Manual therapy
Hands-on treatment may be used to reduce muscle tension, improve joint mobility, and support symptom modulation, particularly in the early stages.
Exercise rehabilitation
A structured rehabilitation programme often forms a key part of recovery. This may include:
Spinal mobility and control work
Hip stability and strength training
Nerve mobility (neural gliding) exercises
Progressive loading strategies
Load management
Adjusting daily activities, sitting time, and exercise load can help reduce irritation while maintaining function.
Education
Understanding what influences symptoms is often a key factor in recovery. Many people benefit from learning how to modify positions and movements without avoiding activity altogether.
Recovery Expectations
Recovery timelines can vary. Some cases improve within a few weeks, while others may take longer depending on the underlying cause and individual factors.
Fluctuation in symptoms is common and does not necessarily indicate worsening. In many cases, the goal is gradual improvement in tolerance to movement and reduction in symptom intensity over time.
When Further Investigation is Needed
While most cases of sciatica are managed conservatively, further medical assessment is recommended if any of the following occur:
Progressive or significant muscle weakness
Loss of bowel or bladder control (urgent medical attention required)
Numbness in the saddle/groin area
Severe, unrelenting pain that does not change with position or rest
Symptoms following significant trauma
These may indicate more serious underlying conditions requiring urgent review.
Summary
Sciatica describes a pattern of symptoms resulting from irritation of the sciatic nerve, most commonly due to changes in the lower back or surrounding structures. While symptoms can be uncomfortable and sometimes limiting, most cases respond well to a structured, movement-based approach to recovery.
Understanding the underlying drivers of symptoms, rather than focusing on pain alone, is often key to longer-term improvement and prevention of recurrence.
