Polish (PL)German (DE)English (EN)
Product information: +48 509 940 633 | Order support: +48 512 999 218
0

What does Lasègue's sign indicate?

20 sierpnia 2023
Lasegue's sign, nervous system, sciatica
The Lasègue's sign, also known as the straight leg raise test, is a significant element in neurological diagnosis, especially in the context of issues related to the spine and sciatic nerve. The name of this sign originates from the French physician Charles Lasègue, who first described this clinical feature in 1864.

In the 19th century, medicine evolved significantly, and clinical observations became a key tool in diagnosing various disorders. During this era, researchers focused on developing techniques and tests that could aid in identifying and understanding diseases and disorders of the nervous system. It was in this context that Dr. Charles Lasègue decided to investigate the impact of different body positions on patients with lower back and limb pain.

His studies led to the discovery of a characteristic sign that now bears his name. The typical Lasègue's sign involves the presence of radiating pain along the sciatic nerve, which may occur when raising the extended lower limb, especially when the patient is lying on their back. When the raised leg reaches a certain angle, the patient's pain may intensify or radiate along the nerve. This sign is significant in the diagnosis of spinal-related disorders such as disc herniation, and also less commonly seen in the population, such as spinal stenosis or radicular syndromes.
Extension of the lower limb sign, spine, spinal structure

Spinal Anatomy and the Lasegue's Sign

The Lasègue's sign is an important indicator of the health of the spine and the nervous system. To fully understand this sign and its connection to spinal anatomy, it's necessary to learn about the structure of the spine and the sciatic nerve.

The human spine consists of several segments, including the cervical, thoracic, lumbar, sacral, and coccygeal segments. Between the individual vertebrae are the intervertebral discs, which serve as shock absorbers and enable spinal movements. In the lower lumbar region of the spine, there are often health issues related to compression of the sciatic nerve.

The sciatic nerve (Latin: nervus ischiadicus), which is the largest peripheral nerve in the human body, originates from the spinal nerves of the lumbar and sacral spine. It runs through the lower spine, then descends along the pelvic bone and thigh. Its main branches innervate the muscles of the lower limb and transmit sensory signals from this important body part to the brain.
The Lasègue's sign is an incredibly important element in diagnosing pain and spinal difficulties.
The Lasègue's sign is caused by compression or irritation of the sciatic nerve. When the nerve is irritated, as in the case of herniated disc, degenerative changes, or stenosis, it can often lead to pain, numbness, or tingling along the nerve. When the raised lower limb, especially when the patient is lying on their back, the nerve can undergo additional compression, causing characteristic radiating pain.

Therefore, proper understanding of the anatomical structure of the spine, intervertebral discs, and the path of the sciatic nerve is crucial in explaining why the Lasègue's sign occurs and what could be its causes. When diagnosing conditions related to the spine and nerves, doctors often rely on the analysis of the Lasègue's sign as an important indicator to determine the cause of painful and neurological symptoms in the patient.
Lasegue's sign, intervertebral discs, sciatic nerve

Differences between the Lasegue's Sign and other back pain symptoms

Differences between the Lasègue's sign and other back pain symptoms arise from the characteristic and mechanism of occurrence of this specific symptom. The Lasègue's sign, also known as the straight leg raising sign, stands out as an indicator of compression or irritation of the sciatic nerve.

In contrast to musculoskeletal pain, the Lasègue's sign is radiating pain that increases during the raising of the elevated leg, especially in a lying position. This sign also differentiates itself from chronic back pain that results from long-term structural issues of the spine. Furthermore, the Lasègue's sign is useful in identifying these conditions as it may indicate compression of the sciatic nerve.

In cases of back pain related to injuries such as various falls or accidents, the Lasègue's sign also stands out. It is closely correlated with the compression of the sciatic nerve, which is typical in herniated disc or radiculopathy. Localized pain associated with a specific spinal area or muscles also differs from the Lasègue's sign. The latter triggers radiating pain along the sciatic nerve, which can extend to the buttock, thigh, and even foot.

Extension of the lower limb sign, spinal degeneration, leg pain

Lasegue's Sign and inflammatory/neurological processes

The Lasègue's sign is a significant element in diagnosing inflammatory and neurological processes, especially in the lower back region. It is particularly useful in effectively identifying issues related to the sciatic nerve that can lead to pain and neurological disorders.

It can occur in cases of inflammatory processes, such as the commonly encountered inflammation of the sciatic nerve (Latin: neuritis) or the rarer inflammation of a nerve root (Latin: radiculitis). In these processes, the sciatic nerve may be irritated or damaged, causing the characteristic pain radiating along the pathway of the nerve. Often, the cause of these processes is a disc herniation that compresses the sciatic nerve and triggers the Lasègue's sign.

Furthermore, the Lasègue's sign can also be associated with various conditions such as root syndromes or neuropathies. Root syndromes are disorders in which nerve roots are compressed or irritated, leading to pain. It may result from nerve disorders stemming from metabolic diseases, infections, or injuries. The Lasègue's sign can also indicate serious sciatic nerve damage associated with these conditions.

The Lasègue's sign serves as an important indicator that may suggest the presence of inflammatory or neurological processes in the spinal and sciatic nerve regions. When evaluating patients with back pain, especially if it radiates along the lower limbs, doctors often use this sign as a significant reference point. It allows them to refer the patient for further examinations and precise diagnosis, enabling appropriate management and treatment of inflammatory processes and neurological disorders.
Lasegue's sign, sciatic nerve, arm pain, intervertebral disc

Treatment and management of patients with a positive Lasegue's Sign

Properly planned treatment and patient management with a positive Lasègue's sign is a comprehensive process that requires understanding the source of pain and adapting therapy to the patient's individual needs. Therefore, it is crucial to determine the exact cause of the sign, based on history, physical examination, and imaging studies.

In many cases, various supplements and pain-relieving medications, as well as anti-inflammatory and muscle relaxant medications, can help alleviate pain. However, involvement in physical therapy is equally important, primarily aiming to improve spinal mobility and strengthen muscles. Patients also learn stretching techniques that reduce muscle tension and thus alleviate pain.

In some situations where conservative methods don't work, invasive therapies are considered. Nerve blocks targeting the sciatic nerve are highly popular, involving the administration of pain-relieving drugs around the nerve and can provide relief. In extreme cases, when a severe disc herniation or spinal deformation is the issue, a challenging decision about surgical intervention may be necessary.

Proper patient education also plays a significant role. Patients must understand their condition and learn self-observation and lifestyle adjustment to prevent recurrences. It's important for patients to be engaged in the treatment process and be aware of available options.

It's worth noting that effective treatment of patients with a positive Lasègue's sign requires a holistic approach. Customizing therapy, primarily considering proper diagnosis, patient needs, and appropriate education, allows for an improvement in the quality of life by alleviating pain and ultimately restoring functionality of the body.
Foam mattresses, mattress store, visco foam, HR

Lasegue's Sign and sleep hygiene

The history of the Lasègue's sign provides a unique example of how careful clinical observations can lead to the discovery of significant diagnostic features. Thanks to the work of Lasègue and other researchers, this sign is now utilized by doctors worldwide as a crucial indicator that can suggest the presence of neurological or orthopedic disorders.

Sleep hygiene plays an essential role in managing the Lasègue's sign and overall spine health. The positive Lasègue's sign, which is radiating pain along the sciatic nerve, can be exacerbated by poor sleep and bad habits related to body position during sleep.

Choosing the right mattress and orthopedic pillow is crucial for maintaining the proper body position while sleeping throughout the night. A foam mattress with the appropriate degree of firmness and full functionality, along with a good pillow that adequately supports the spine, can help avoid improper body alignment that could aggravate pain associated with the Lasègue's sign.
A positive Lasègue's test result should prompt reflection on sleep hygiene.
Choosing the right sleeping position is also crucial. If you experience the Lasègue's sign, lying on your back with raised legs can be more comfortable as it reduces pressure on the sciatic nerve. If you prefer side sleeping, place a pillow between your knees to keep your spine in a straight line.

Avoid sleeping in a twisted position that can lead to back muscle tension and increased pain. Strive to maintain a natural spinal alignment during sleep. Keeping a regular sleep schedule is also crucial for overall spine health. Improper or irregular sleep can affect muscle and nervous system condition, which in turn can exacerbate the Lasègue's sign.

It's important to remember that sleep hygiene influences the Lasègue's sign by shaping body positioning during sleep and maintaining overall spinal health. Therefore, choosing an appropriate mattress such as the highly functional Osaka Air mattress, along with sleeping position and ensuring consistency and quality of sleep, can help reduce pain and consequently enhance the comfort of experiencing patients.

We also encourage you to explore other articles on the best sleep and health blog, as well as the Encyclopedia of Healthy Sleep prepared by the ONSEN® team of specialists. For those who care about spine health, we recommend a set of spine exercises prepared by our physiotherapist.
Spine mattress, medical store Toruń, sciatica

FAQ: Lasègue's sign

What is the Lasegue's sign?

The Lasegue's sign, also known as the straight leg raise test, is a clinical test used to diagnose issues with the sciatic nerve and the spine. It involves inducing radiating pain along the sciatic nerve by raising the extended lower limb.

What might a positive Lasegue's sign indicate?

A positive Lasegue's sign, meaning the occurrence of pain or radiating discomfort during the test, can suggest compression of the sciatic nerve. This could be caused by problems such as a herniated disc, spinal stenosis, or root syndromes.

How is the Lasegue's test performed?

The Lasegue's test involves lifting the patient's extended leg while they are in a lying position. The doctor raises the patient's leg until the patient reports pain or discomfort along the sciatic nerve. The angle at which the pain occurs might be significant for diagnosis.

What is the crossed femoral Lasegue's sign?

The crossed femoral Lasegue's sign, also known as the reverse Lasegue's sign, is a test used to diagnose issues with the spinal nerves. It involves lifting the healthy leg of the patient on the opposite side. If pain occurs on the side where the symptom wouldn't appear in the standard test, it could indicate compression of a nerve root.

How does the Lasegue's sign differ from the Kernig's sign?

Both of these clinical features are used to diagnose neurological problems but in different contexts. The Lasegue's sign involves inducing pain along the sciatic nerve by raising the extended leg. On the other hand, the Kernig's sign is a symptom seen in cases of meningeal infections, where lifting the extended leg of the patient causes resistance or pain in the lower back.

Share
Newsletter - stay up to date!
Without your consent, we cannot add your e-mail address to the ONSEN® newsletter subscriber base.
Thank you for joining the ONSEN® newsletter subscriber group!
Comments
There were errors in the form.
First name or nickname *
E-mail address (will not be visible)
Telephone number (will not be visible)
Comment *
Thank you for adding a comment!
More about how to live and function healthily...