Sciatica is usually felt as pain that travels from the lower back or buttock down the leg. It may be accompanied by tingling, numbness, an electric shock sensation, or weakness. However, the cause is not always the same.
The key is to observe how the pain began, where it travels, what makes it worse, what relieves it, and whether there are any neurological symptoms. Even so, a definitive diagnosis usually requires a clinical examination. This article is intended to provide guidance, not a diagnosis. If you experience progressive loss of strength, loss of bladder or bowel control, genital numbness, sudden bilateral pain, fever, a history of cancer, significant trauma, or nighttime pain that does not subside, seek urgent medical attention.
Why is it important to understand the cause of your sciatica?
The cause of sciatica matters because it determines the treatment. Sciatica that worsens when sitting is not the same as one that appears when walking, or one related to a herniated disc, or one caused by lumbar stenosis. Knowing the likely origin helps in choosing the best care and knowing when to consult a doctor.
When sciatic pain travels like a shock: lumbar herniated disc
One of the most frequent causes of sciatica is a lumbar herniated disc. It occurs when part of the disc's internal material protrudes through a fissure and can compress or irritate a nerve root.
Regarding pain, some people tolerate lumbar extension postures (a gentle arching backward) better, whereas sitting for long periods usually increases pressure on the disc and worsens symptoms.
When sciatica is due to a herniated disc, it does not always become a recurring problem. For many people, it appears as an acute episode that improves with time and conservative treatment, and may not recur. Even so, for others, it may reappear, especially if risk factors, overexertion, poor tolerance to effort, or new episodes of disc irritation persist.
Clues that point to a herniated disc
- Pain that travels down one leg, often below the knee
- Burning sensation, electric shock, or sharp pain
- Worsens when coughing, sneezing, bending, or sitting
- May include tingling, loss of sensation, or weakness
- Usually affects one side more than both
- The pain can behave "mechanically": certain movements clearly trigger the sciatica while others relieve it.
The American Academy of Orthopaedic Surgeons notes that in people under 40, the typical cause of sciatica is usually a herniated disc.
Treatment if the cause of sciatica is a herniated disc
When sciatica is due to a herniated disc, the initial goal is usually to reduce inflammation and nerve root irritation. In many cases, the following are recommended:
- Maintain gentle activity and walk as much as tolerable
- Avoid heavy lifting or repetitive bending if they increase the pain
- Frequent posture changes
- Progressive exercises guided by physical therapy
- Analgesics or anti-inflammatory drugs if indicated
When walking makes it worse and sitting brings relief: lumbar stenosis
Lumbar spinal stenosis occurs when the spaces in the spinal canal or where the nerves exit narrow. With less space, nerves can become irritated or pinched. This can cause lower back pain, buttock pain, leg pain, tingling, cramps, or a feeling of heaviness.
It is usually more frequent in people over 50 because the spine can wear down over time. That wear and tear can cause discs to bulge, osteoarthritis to develop, and ligaments to thicken... All of this can reduce the space available for the nerves.
In less common cases, the narrowing can also be due to a fracture, a cyst, or a tumor.
Clues that point to lumbar stenosis
- Pain or heaviness in one or both legs
- Worsens when standing, walking in general, or walking downhill
- Improves when sitting, crouching, or leaning forward
- May feel better walking while leaning, as if supported
- More common in people over 50 years of age
The classic pattern of lumbar stenosis is pain that worsens when standing and improves when sitting or leaning forward.
Treatment if the cause of sciatica is lumbar stenosis
In lumbar stenosis, the problem is usually the narrowing of the canal through which the nerves pass. For this reason, many people find relief by:
- Sitting
- Leaning forward
- Walking while supported by a walker or cane
- Performing lumbar flexion exercises
Physical therapy usually focuses more on improving walking tolerance, flexibility and mobility, core and glute strengthening, and postural strategies.
Unlike some herniated discs, which can improve significantly over time, lumbar stenosis tends to behave as a more chronic and degenerative problem. Symptoms can fluctuate, with better and worse periods, and gradually reappear when walking or standing for longer periods.
When a vertebra slips: spondylolisthesis
Spondylolisthesis occurs when one vertebra shifts in relation to the vertebra below it. Here, the pain often worsens with prolonged standing, extended walking, or extending the back backward.
Clues that point to spondylolisthesis
- Lumbar pain (with or without pain traveling to the buttocks or legs)
- Worsens when standing, walking, or extending the back
- May include lumbar stiffness or tight hamstrings
- Can appear in young athletes or older adults due to degeneration
Treatment if the cause of sciatica is spondylolisthesis
Treatment begins with relative rest from aggravating activities, anti-inflammatories or analgesics if they are safe for the individual, and physical therapy to strengthen the back and core muscles.
Surgery is reserved for high-grade slippage, severe pain that limits walking or standing, or symptoms that persist despite non-surgical treatments. In these cases, spinal fusion and/or decompression may be considered to reduce pressure on the sciatic nerve.
When the problem originates in the buttock: piriformis syndrome
The piriformis syndrome occurs when the piriformis muscle compresses or irritates the sciatic nerve in the buttock area. It may resemble lumbar-origin sciatica, but the focus is usually more localized in the buttock, hip, or upper part of the leg.
This cause is very uncommon; according to the Cleveland Clinic, only between 0.3% and 6% of cases are due to piriformis syndrome. In fact, this diagnosis is primarily clinical and one of exclusion.
Clues that point to piriformis syndrome
- Deep pain in the buttock
- Worsens when sitting for a long time
- May worsen when climbing stairs, walking, or running
- May feel like burning, tingling, numbness, or sharp pain
Treatment if the cause of sciatica is piriformis syndrome
Since the pain here is usually more related to muscle tension, local nerve compression, or buttock overuse, the following usually help:
- Specific stretches
- Myofascial release techniques
- Progressive hip and glute strengthening
- Correction of biomechanical overloading
Sciatica during pregnancy: when the pelvis, posture, and load change
During pregnancy, lumbar, pelvic, or pain traveling toward the buttocks and legs can appear. Back pain is common in pregnancy because ligaments soften and stretch to prepare for childbirth, which can overload the lower back and pelvis. In addition, the shift in the center of gravity, ligamentous laxity, weight gain, and occasionally the position of the fetus can contribute to irritating or compressing the sciatic nerve.
Many pregnant women improve with gentle exercise, adapted physical therapy, sleeping on the side with a pillow between the legs, and avoiding staying in the same posture for a long time.
Summary of possible causes of sciatica and how to identify them
| Possible cause of sciatica | Frequent clues |
|---|---|
| Lumbar herniated disc | Electric pain down a leg, worsens with coughing, sneezing, bending, or sitting; possible tingling/weakness |
| Lumbar stenosis | Over 50, leg pain/heaviness when walking or standing, improves when sitting or leaning |
| Spondylolisthesis | Lumbar pain, stiffness, worsens standing or walking; may travel to legs |
| Piriformis syndrome | Deep buttock pain, worse when sitting, running, walking, or climbing stairs |
| Pregnancy / pelvic girdle | Lumbar, pelvic, or buttock pain during pregnancy; worse when walking, climbing stairs, or turning in bed |
When the pain seems like sciatica but is not sciatica
Not all pain that travels to the buttock or leg is true sciatica. There are muscular, joint, or hip problems that can produce very similar pain.
Sacroiliac pain: when the problem is in the pelvis
The sacroiliac joint connects the spine to the pelvis. When irritated, it can cause pain in the lower back, buttock, hip, and even the back of the leg.
It is sometimes confused with sciatica because the pain can travel down, but usually:
- It does not follow a clear nerve path
- It often hurts more in a specific spot near the buttock
- There is not always tingling or loss of sensation
In these cases, the pain usually worsens when:
- Standing for a long time
- Climbing stairs
- Turning in bed
- Bearing weight on one leg
Greater trochanteric pain syndrome: lateral hip pain that can extend
Also called trochanteric bursitis, it can cause pain on the side of the hip that sometimes extends toward the thigh.
It can be confused with sciatica, but usually has differentiating clues:
- Pain when sleeping on that side
- Tenderness when touching the side of the hip
- Discomfort when walking or climbing stairs
- Fewer typical neurological symptoms
Hip problems felt in the leg
Hip osteoarthritis and other joint problems can also cause pain toward the buttock, groin, thigh, or even the knee. However, unlike sciatica:
- There is usually joint stiffness
- Difficulty crossing legs or putting on socks (see sock aid)
- Pain with certain hip movements
When the pain comes from the muscle and not the sciatic nerve
Sometimes the pain that travels toward the buttock or leg does not come from a compressed nerve, but from irritated or overloaded muscles.
Muscles in the lower back, pelvis, or buttock can form highly sensitive areas known as trigger points. They are like muscle knots that hurt when pressed and, in some people, can send pain to other areas. This type of pain usually feels like:
- Muscle tension or heaviness
- Deep pain in the buttock or lower back
- Diffuse burning sensation
- Discomfort that changes depending on posture or activity
- Pain when pressing a specific area of the muscle
The difference from sciatica is that, generally, muscular pain does not usually cause clear signs of nerve damage (there is no real loss of strength, markedly numb areas, or difficulty moving the foot or leg).
Try to distinguish it this way: if touching or pressing a point in the buttock or back reproduces the pain that travels down the leg, it may be referred muscle pain. Even so, professional assessment is important, because true sciatica and muscle pain can look very similar.
