Numbness and radiculopathy

What is Sciatica?

Sciatica is a condition where the sciatic nerve is irritated or inflamed causing nerve pain in the patient. The hallmark characteristics of sciatica is radiating or shooting sharp nerve pain down the entire leg. The sciatic nerve is the largest branch of the sacral plexus and is the largest nerve in the body. It branches from the lower back (L4 to S3), passes through the sacral promontory and ala and descends in front of the piriformis muscle into the posterior thigh. It then continues as the tibial and common fibular nerves travelling down the leg and towards the foot. Lumbar disc herniation or inflammation is one of the most common factors causing compression of the sciatic nerve thus sciatica.

Cause of Sciatica

Sciatica can be caused by multiple factors; spinal disc herniation, spinal stenosis and piriformis syndrome are amongst the most common. As mentioned above, spinal disc herniation in the lumbar spine accounts for about 90% of all sciatica cases under 50. Injury or abnormal increase in pressure loading of the spinal discs can results in herniation and swelling or inflammation of the disc, which can lead to compression of the sciatic nerve root. With lifting injuries, patients commonly report an increase of pain when bending forward or sitting. Pain level is usually very high.

Spinal stenosis is a less common contributor to sciatica; however, it is the most common chronic cause of sciatica; over the age of 50. Lumbar spinal stenosis is a condition where the space where the nerve passes through and exits is narrowed due to osteophytes (bone spurs) or spondylolisthesis etc. With decreased available space for the nerve to exit, the chances of compression or irritation increases. Due to the nature of osteophytic degeneration, treatment can be complicated compared to other causes of sciatica.

Lastly, piriformis syndrome is a less common condition that can contribute to sciatica. It accounts for 8% of lower back or buttock pain and is usually diagnosed as an association with sciatica. In 17% of people, the sciatic nerve runs through the piriformis muscle rather than beneath it, thus when the muscle spasms due to injury or overuse, the sciatic nerve can be irritated, causing sciatic pain. Piriformis syndrome has been referred to as “Wallet syndrome” where carrying a wallet in the rear hip pocket for an extended period of time can compress the piriformis muscle causing inflammation and sciatic pain. Sciatica caused by piriformis syndrome is usually the least severe and easiest to resolve.

Risk factors of sciatic includes smoking, obesity and occupational and physical injuries. Non-modifiable risk factors includes aging, being male and having a history of lower back pain. Less reported risk factors includes a history of hip replacement with an association of 0.5%-2% chance of sciatica as a complication.

Cause and Symptoms

The symptoms of sciatica can last for several weeks to several months or even years or more. It is common in men aged 30-50 or older, with a ratio of affected individuals being 4:1 compared to women. Due to the high level of pain, patients often feel restless when the pain occurs; they may experience an electric shock-like stabbing pain, and common symptoms include an inability to bend over, difficulty walking, weakness in both legs, difficulty sitting down, sleep disturbances or inability to sleep, and impacts on normal life. Most patients will have noticeable pain and numbness in the lumbar region, such as aching pain, tingling, or burning sensations. There may also be numbness and pain extending from the calf to the foot, feelings of weakness, and reduced or lost sensation in the lower limbs. If the nerve damage is severe, it may also lead to muscle atrophy, abnormal reflexes, or even affect bladder and bowel functions, resulting in incontinence, impotence, and paralysis.

Treatment methods

The treatment for sciatica mainly includes four types: spinal structural correction therapy, medication, steroid injections, and surgical treatment.

Sciatica is generally caused by instability in the pressure on the intervertebral discs and spine, leading to inflammation of the soft tissues around the intervertebral discs and spine, which compresses the sciatic nerve and causes pain symptoms. Patients can maintain spinal stability through spinal correction therapy. When there are issues with the lumbar spine and vertebrae, a detailed full spine assessment by a doctor and X-ray diagnosis can determine the health of the intervertebral discs and the extent of nerve tissue compression, as well as the overall condition of the spine. Manual therapy and treatment plans designed by the doctor can correct issues such as herniated discs and soft tissue inflammation, strengthen the surrounding soft tissues, and stabilize the structure, allowing patients to achieve long-term recovery.

Another method for treating sciatica is taking medication to relieve pain, including anti-inflammatory pain relievers, non-steroidal drugs, nerve pain medications, and muscle relaxants. Depending on the situation, the doctor may prescribe medication for 6-8 weeks to alleviate symptoms of nerve compression. If the pain does not subside, patients may choose to receive epidural steroid injections in the spine. The epidural space is located between the outer layer of the dura mater and the spinal bones, and epidural steroids involve injecting corticosteroids into the epidural space, which can reduce irritation to the nerve roots and provide pain relief, anti-inflammatory, and swelling-reducing effects. Generally, the pain relief from injections can last from a few weeks to three months, with the effects being relatively short-term, and long-term steroid injections are not recommended due to potential side effects.

Finally, if long-term conservative treatment does not alleviate nerve pain or if significant symptoms such as loss of sensation in limbs or incontinence occur, consideration should be given to performing a discectomy. The doctor will make a precise two-centimeter skin incision in the lower back and, with the assistance of a microscope or endoscope, remove the herniated intervertebral disc. Patients can generally get out of bed on the same day after surgery or return home to rest within a few days.

Dr. Lai’s Recommendations:

To avoid triggering lumbar pain and diseases, daily attention should be paid to maintaining the spine, exercising more, and not smoking. For those who often sit for long periods, such as office workers or frequent computer users, it is important to maintain correct sitting posture and avoid crossing legs; when sitting, the lumbar spine should be pressed against the back of the chair, kept straight, and shoulders relaxed. Those who sit for long periods should stand up and move or stretch every 45 minutes to relieve the pressure on the spine. Additionally, individuals who frequently lift heavy objects or move things need to pay attention to correct lifting posture, avoiding bending at the waist and instead squatting to lift, to prevent excessive strain on the lumbar spine, which can lead to disc herniation or bone spurs compressing the nerves. Furthermore, individuals who are overweight or obese place excessive load on the lumbar spine due to their weight, so it is recommended to engage in moderate exercise to strengthen muscle activity and spinal health. For those who exercise regularly, attention should be paid to whether their posture during exercise is correct to avoid injuries that could affect the spine and cause pain. If there are concerns about having sciatica or other spinal issues, it is advisable to seek medical attention as soon as possible, consult a doctor for professional advice, and undergo a detailed full spinal assessment to find suitable treatment options for sciatica.