1. From low back pain to the soles of the feet! Why does sciatica occur?

If the pain "extends from the waist to the legs," beware that it may be a warning sign of "sciatica." First, let's understand the "sciatic nerve": it is formed by the fourth and fifth lumbar nerves and the first, second, and third sacral nerves, and runs from the buttock muscles all the way down to the lower limbs. When the sciatic nerve is compressed, pain or numbness spreads from the lower back along the nerve pathway to the buttocks, thighs, calves, and even the feet.

Sciatica is mainly caused by compression of the nerve roots, especially the fourth or fifth lumbar nerve root or the first sacral nerve root; these nerves make up part of the sciatic nerve. The most common cause is a herniated disc. When the nerve root is compressed, it triggers an inflammatory response, leading to acute or chronic sciatica. In addition, lumbar fractures after bone loss and degenerative lumbar arthritis may also narrow the intervertebral foramina due to spinal degeneration, thereby compressing the nerve roots.

Other possible causes of sciatica include spondylolisthesis, which can compress nerve roots and cause pain. Tumors of the spine or spinal cord, fractures, and spinal infections such as spinal tuberculosis may also be triggers. In addition, deep gluteal syndrome originating from the buttocks—where the deep gluteal muscles become overly tight or inflamed and compress the sciatic nerve—can also cause pain or numbness in the lower limbs. Spinal stenosis, muscle tightness, or poor posture may also cause compression or irritation of the sciatic nerve, leading to pain.

2. What symptoms can sciatica cause? Severe cases may lead to incontinence and difficulty walking

The symptoms of sciatica range widely from mild to severe. Mild symptoms may include intermittent tingling, numbness, or burning sensations in the lower back, buttocks, or lower limbs. Pain may extend along the back or outer side of the leg to the foot, but not enough to affect daily activities. Patients may feel tightness or tingling in the leg, especially after sitting or standing for long periods; symptoms may come and go and improve after rest.

Moderate symptoms present as more noticeable and persistent pain and numbness, and mobility is also affected. Patients may be unable to stand or sit for long periods, and pain worsens when bending over or lifting heavy objects. The pain may feel like a slight electric shock, extending to the thigh, calf, or sole of the foot. Crossing the legs may worsen numbness or pain, and activity is limited. Severe symptoms include intense pain, leg weakness or muscle atrophy, and even incontinence or reduced sensation in the feet, affecting normal walking and activity.

Patients with sciatica may be unable to perform simple leg-lifting movements, and the pain can be as intense as an electric shock. Actions that increase intra-abdominal pressure, such as coughing or sneezing, will worsen the pain. These symptoms can seriously affect daily life and work. It should be noted that with sciatica or lower-limb ischemia, the degree of claudication is usually at least "moderate to severe." If lower back pain continues without improvement, be very careful and do not take it lightly!

3. How is sciatica diagnosed? Doctor says: it can be clarified with "these 2 movements"

Diagnosis of sciatica mainly relies on symptoms and physical examination, such as radiating pain, numbness, or tingling extending from the lower back to the buttocks and lower limbs. A common physical exam is the Straight Leg Raising Test (SLRT). When a patient is lying flat, if raising the leg between 30 and 70 degrees causes increased leg pain, it may indicate irritation of the nerve root. In addition, patients may be unable to stand on tiptoe or walk on their heels; doctors will also check for reduced sensation or abnormal muscle reflexes.

However, the results of physical examinations are sometimes influenced by the patient's subjective description and the examiner's level of skill, so a doctor's comprehensive assessment is still needed before arranging appropriate imaging studies. Imaging studies such as MRI or CT are also important tools for diagnosing sciatica. X-rays help confirm conditions such as spondylolisthesis, degenerative bone spurs, or narrowing of the intervertebral disc space; magnetic resonance imaging (MRI) can more clearly determine the degree of spinal stenosis and nerve root compression.

We would like to remind the public that if you feel pain extending from the waist to the soles of the feet, and if this pain persists for more than a week and is accompanied by muscle weakness, loss of sensation, or incontinence, please seek medical attention as soon as possible to receive an appropriate diagnosis and treatment!