Spinal stenosis

Overview

Spinal stenosis is a disorder characterized by nerve root compression caused by a variety of pathologic causes, resulting in symptoms such as pain, weakness, and numbness. Each degree of compression might cause distinct symptoms depending on the position of the afflicted spine, necessitating a different treatment technique.

What is Spinal stenosis?

Spinal stenosis is a disorder in which the nerve roots get compressed as a result of a variety of pathologic conditions, resulting in symptoms such as pain, numbness, and weakness. The upper neck (cervical) and lower back (lumbar) are the most commonly afflicted locations, while the thoracic spine can also be squeezed by a disk herniation. Spinal stenosis can impact three separate anatomic areas inside the vertebral canal.

First, the central canal, which houses the spinal cord, might narrow in an anterior-posterior dimension, causing neural components to compress and blood flow to the spinal cord in the cervical area and the cauda equina in the lumbar area to be reduced. Second, as a result of disk herniation, hypertrophy of the facet joints and ligaments, or unstable sliding of one vertebral body relative to the level below, the neural foramen, which are apertures through which the nerve roots leave the spinal cord, might be squeezed.

Finally, a facet joint hypertrophy can compress the lateral recess, which is exclusively observed in the lumbar spine and is described as the place along the pedicle that a nerve root penetrates immediately before exiting via the neural foramen.

The majority of patients will feel some form of back discomfort, but fortunately, even without surgery, the majority will heal without incident. Only 1-3 percent will have a herniated disc, and fewer than 2% will suffer nerve root compression.

Spinal stenosis is prevalent as people age, but it is impossible to anticipate who may develop symptoms. In most situations, adjustments in lifestyle can limit the degenerative process.

Anatomy

Central canal stenosis is a midline sagittal spinal canal diameter narrowing that can cause neurogenic claudication (NC) or discomfort in the buttock, thigh, or leg. It is most usually found at an intervertebral disk level. This stenosis is caused by ligamentum flavum hypertrophy, inferior articulating process (IAP), cephalad vertebral facet hypertrophy, vertebral body osteophytosis, vertebral body compression fractures, and herniated nucleus pulposus (HNP).

In a normal-sized canal, disk abnormalities normally do not induce symptoms of central stenosis. A noticeable bulge or modest herniation in a developmentally tiny canal, on the other hand, might create symptomatic central stenosis. Large disk herniations can compress the dural sac and jeopardize its nerves, especially at the higher cephalad lumbar levels where the dural sac includes more nerves.

In the United States, acute and chronic neck and lower back pain are important health-care issues. Back pain affects around 75% of all people at some point in their life. The majority of individuals who arrive with an acute bout of back pain recover without surgery, but 3-5 percent have a herniated disc and 1-2 percent have nerve root compression. Patients above the age of 65 have more chronic or recurring symptoms of degenerative spinal degeneration.

Progressive spinal canal narrowing can develop alone or in conjunction with acute disc herniations. Congenital and acquired spinal stenoses increase the patient's risk of acute neurologic damage. The cervical and lumbar spines are the most commonly affected by spinal stenosis.

Cervical spine movement aggravates congenital or acquired spinal stenosis. The cervical chord expands in diameter during hypertension. The anterior roots are constricted within the canal by the annulus borders and spondylitic bony bars. Hypertrophic facet joints and thicker infolded ligamentum flavum in the posterior canal compress the dorsal nerve roots. Neural structures are linked anteriorly to the bulging disc annulus and spondylitic bars during hyperflexion. When a vertebral collapse occurs, the cervical spine loses its form, which can lead to anterior cord compression.

Hypertrophy of the ligamentum flavum, bone spondylitic hypertrophy, and disc annulus bulging all contribute to the development of central spinal stenosis in the central cervical spinal area. The proportional importance of each component contributing to the stenotic pattern varies in each situation.

Congenital cervical spine stenosis may predispose a person to myelopathy as a result of mild trauma or spondylosis.

Epidemiology

Spinal stenosis affects between 250,000 and 500,000 people in the United States. This equates to roughly 1 in 1000 people over the age of 65 and about 5 in 1000 people over the age of 50. Around 70 million Americans are over the age of 50, and this figure is expected to climb by 18 million in the next decade alone, implying that the frequency of spinal stenosis will rise.

Lumbar spinal stenosis (LSS) is still the most common preoperative diagnosis in persons over the age of 65 undergoing spine surgery. According to reports, lateral nerve entrapment affects 8-11 percent of people. According to certain research, lateral recess stenosis is the source of discomfort for 60% of individuals with failed back surgery condition.

As many as 35% of people aged 20-39 years who are asymptomatic have disc bulging. CT scans and MRI investigations in asymptomatic patients under the age of 40 show a 4-28 percent incidence of spinal stenosis. Most people over the age of 60 have some degree of spinal stenosis. Because the vast majority of people with moderate spinal stenosis have no symptoms, the absolute prevalence can only be calculated.

Because to increasing dorsal root ganglion (DRG) diameter and resultant smaller foramen, the incidence of foraminal stenosis rises in the lower lumbar levels (ie, nerve root area ratio). Jenis and An list the most usually affected roots as L5 (75%), L4 (15%), L3 (5.3%), and L2 (4 percent )

Lower lumbar levels have increased obliquity of nerve root passage as well as a higher prevalence of spondylosis and DDD, which predisposes individuals to L4 and L5 nerve root impingement.

Cervical stenosis caused by ossification of the posterior longitudinal ligament is more common in Asians, while LSS is more common in men. Patients with LSS owing to degenerative causes are often beyond the age of 50; however, LSS may be present at a younger age in cases of congenital abnormalities.

Spinal stenosis causes

Congenital or acquired etiologies can cause spinal stenosis. Congenital etiologies account for just 9% of all cases. Achondroplasia, shorter pedicles, osteopetrosis, apical vertebral wedging, spinal dysraphism, segmentation failure early vertebral arch ossification, thoracolumbar kyphosis, morquio syndrome, and osseous exostosis are some frequent congenital causes.

Trauma, degenerative changes, iatrogenic causes, and systemic processes are the most common causes of acquired stenosis. Trauma often causes an immediate mechanical stress to alter the spinal canal. Degenerative alterations occur when the central canal and lateral recess narrow due to posterior disk herniation, ligamentum flavum hypertrophy, or spondylolisthesis. Iatrogenic spinal stenosis can be caused by laminectomy, fusion, or discectomy surgery.

Pathophysiology

Spinal stenosis is a disease condition that causes the vertebral spinal canal and lateral recesses to narrow. This frequently results in compression of components within the spinal canal, such as the spinal cord, surrounding nerve tissue, and cerebrospinal fluid. A variety of causes might contribute to the narrowing.

This involves bulging or protrusion of the intervertebral disc, posterior nucleus pulposus herniation, epidural fat deposition, hypertrophy of the posterior longitudinal ligament or the ligamentum flavum, and facet joint hypertrophy. A spinal cord injury can cause serious consequences such as myelopathic syndrome or cauda equina syndrome.

Symptoms of Spinal stenosis

A complete history of symptoms and a physical exam, with an emphasis on sensation, motor strength, reflexes, specific tests, and gait, are commonly used to evaluate a patient with spinal stenosis. Cervical spine stenosis can cause radicular symptoms from nerve root compression and myelopathy from spinal cord compression. Patients first complain of neck or arm ache.

Radicular symptoms arise when a patient's nerve root is impinged, and they vary depending on the level affected. A C5-6 disk herniation, for example, causes C6 radiculopathy. The most prevalent is a C6-7 disk herniation, which causes a wrist drop and paresthesia in the second and third digits. The C5-6 disk herniation is the most frequent, resulting in forearm flexion weakness and paresthesia in the thumb and radial forearm.

A herniated C7-T1 disk can cause weakness in the intrinsic muscles of the hand as well as numbness in the fourth and fifth fingers. Finally, a herniated C4-5 disk might cause deltoid weakness and shoulder paresthesia. Pain and paresthesia in the head, neck, and shoulder are also possible. Cervical spondylotic myelopathy can be found in individuals with more than 30% spinal constriction, resulting in upper extremity clumsiness, gait disruption, lower limb weakness, and ataxia.

Neurogenic claudication, myeloradiculopathy symptoms, sensory abnormalities, motor weakness, and pathologic reflexes can all result from lumbar spine stenosis. Patients will complain of cramping discomfort in their leg, calf, or buttocks. They may experience more discomfort when walking or standing for extended periods of time, and alleviation when sitting or leaning forward when using a shopping cart.

The L4-5 and L5-S1 levels are the most commonly affected by disk herniation. A herniated disk at L5-S1 can produce plantarflexion weakness, lateral foot feeling loss, and discomfort in the posterior leg. A L4-5 disk herniation can cause a foot drop as well as numbness in the big toe web and dorsal part of the foot. Finally, an L3-4 disk herniation might cause knee extension weakness, medial foot numbness, and anterior thigh discomfort.

Diagnosis

Imaging with an extended-release x-ray, CT, and MRI can be used to make a diagnosis. With the advent of MRI, plain radiographs are of minimal utility, albeit dynamic images in flexion and extension modes can show dynamic instability or spondylolisthesis. CT can assist in distinguishing calcified disks or bone osteophytes from "soft disks," distinguishing ossification of the posterior longitudinal ligament from a thicker posterior longitudinal ligament, and detecting bone fractures or lytic lesions.

The gold standard is MRI, which can detect intrinsic cord anomalies, determine the degree of spinal stenosis, and distinguish between various disorders such as tumors, hematomas, and infections. If a patient has a pacemaker and is unable to get an MRI, a CT myelogram can be used to determine the amount and degree of stenosis.

Electrodiagnostic investigations are frequently used to assist rule out and rule in a diagnosis. Nerve conduction tests, needle electromyography, and somatosensory evoked potentials were performed.

The purpose of spine imaging is to pinpoint the location and severity of illness. It is also used to assist distinguish between illnesses for which patients require surgery and those for which patients can recover with conservative therapy. Standard radiography, magnetic resonance imaging (MRI), computed tomography (CT) scanning, nuclear imaging, and angiography are all imaging investigations employed in LSS.

Treatment for spinal stenosis

Conservative therapy with bracing, rest, or anti-inflammatory drugs can be used in individuals with cervical stenosis who do not have myelopathy. For patients suffering from myelopathy, surgical decompression can give some relief from pain and sensory loss while also preventing the disease from worsening.

To alleviate compression and stabilize the spine, anterior or posterior decompression and fusion might be used, depending on the levels involved and the disease. Back pain in the lumbar spine can be managed first with NSAIDs and physical therapy, followed by interventional pain management techniques for persistent pain.

When conservative treatment fails or the patient develops progressive myelopathy, neurologic impairments, or spinal instability, surgical decompression and fusion are advised. Depending on the nature of the disease, an anterior, lateral, or posterior approach can be used to restore lumbar lordosis, decompress the stenosis, and induce fusion.

Differential Diagnosis

Lumbar Compression Fracture
Lumbar Degenerative Disk Disease
Lumbar Facet Arthropathy
Lumbar Spondylosis
Mechanical Low Backpain
Rehabilitation for Osteoarthritis
Rheumatoid Arthritis
Spondylodiskitis
Spondylolisthesis Imaging

Lumbar Spinal stenosis

Lumbar spinal stenosis is a common cause of discomfort in the legs and back. It refers to a constriction in the spine, specifically in the central canal, lateral recess, or neural foramen. Symptoms of lumbar radiculopathy may appear when the lateral recess and neural foramen are stenosed. Despite its frequency, there is presently no internationally accepted definition of lumbar spinal stenosis, nor are there generally agreed radiologic diagnostic criteria.

Lumbar spinal stenosis is a major source of impairment in the elderly, and it is the leading reason of spine surgery in individuals over the age of 65. As a result, doctors must properly detect and treat lumbar spinal stenosis.

Degenerative spondylosis is a major cause of lumbar spinal stenosis. The intervertebral discs can deteriorate and protrude posteriorly as a result of age, wear-and-tear changes, and traumas, among other reasons, generating higher loading of the vertebral posterior parts. These modifications can result in the creation of posterior vertebral osteophytes (uncinate spurs), facet hypertrophy, synovial facet cysts, and ligamentum flavum hypertrophy, all of which can contribute to spinal stenosis.

Another cause of lumbar spinal stenosis is degenerative spondylolisthesis. When the pars interarticularis fractures due to degenerative changes in the spine, the accompanying instability might cause the vertebra to move forward. Sufficient anterior slippage of one vertebra on top of the next (most often L4-on-L5) can restrict the spinal canal, resulting in stenosis.

Anatomically, lumbar spinal stenosis is divided into two types: central stenosis, which is caused by a combination of hypertrophied ligamentaum flavum anteriorly and bulging disc posteriorly, resulting in thecal sac compression, and lateral recess stenosis, which is caused by facet joint arthropathy with overgrowth of the superior articular facet and osteophyte formation.

As a result, the descending nerve roots are compressed. Foraminal stenosis is caused by a decrease of disc height, a protrusion of the foraminal disc, or the growth of an osteophyte, resulting in compression of the exiting nerve root. Finally, extraforaminal stenosis is caused by far lateral disc herniation, resulting in exiting nerve root compression.

Lumbar spinal stenosis often manifests as discomfort that is increased by prolonged ambulation, standing, and lumbar extension, and is alleviated by forward flexion and rest. Neurogenic claudication is a common symptom of lumbar spinal stenosis. Symptoms are frequently bilateral but asymmetric. The majority of patients have low back discomfort, numbness, and tingling. In lumbar spinal stenosis, numbness and tingling often impact the entire leg and seldom affect simply a particular nerve root distribution.

Weakness affects around 43% of the patients. Patients may also say that going upstairs is easier than walking downhill since the back is bent forward when ascending stairs. Cauda equina or conus medullaris syndromes may occur in individuals who report with new-onset bowel or bladder dysfunction, saddle anesthesia, bilateral lower limb weakness, and/or increasing lower extremity.

The goal of lumbar spinal stenosis treatment is to alleviate symptoms and improve functional status. The first-line therapy for this illness is conservative treatment. Physical therapy, anti-inflammatory medicines, and epidural steroid injections are examples of conservative treatments. Although there is no conventional physical treatment routine, many therapists focus on stretching and strengthening core muscles, which can result in improved posture and symptoms.

Although there are short-term benefits, lumbar epidural steroid injections have not been shown to improve long-term pain and disability in patients with lumbar spinal stenosis, and there is no statistical difference between epidural injections with anesthetics alone versus a mixture of anesthetics and corticosteroids. Lumbar corsets may also be used for short pain alleviation.

Conclusion

Narrowing of the spinal canal or foramina is a typical observation in senior spine imaging. A spinal stenosis diagnosis of the lumbar spine, cervical spine, or both is made only when symptoms of neurogenic claudication and/or cervical myelopathy are evident.

Patients with spinal stenosis are frequently seen by a nurse practitioner, primary care physician, emergency room physician, or internist. If the patients are asymptomatic, there is typically no need for therapy. Patients suffering from discomfort should be urged to engage in an activity regimen, quit smoking, and maintain a healthy weight.

Only a few people should be referred to an orthopedic or neurosurgeon if they have nerve compression. However, primary care physicians should inform the patient about the surgery's possible consequences, which can be devastating.

It is critical to assemble an interprofessional team of physicians (physical medicine and rehabilitation, pain management, orthopedists, and/or neurosurgeons), physical therapists, occupational therapists, social workers, and case managers who can collaborate to coordinate mobilization with outpatient therapy and aggressive multifaceted rehabilitation in order to improve a patient's functional status.

In the outpatient environment, lumbar spinal stenosis is a frequent disease condition. These people are suffering from symptoms such as leg discomfort and low back pain. This disorder is most likely caused by prolonged wear-and-tear injury to the spinal column.

Despite the fact that imaging scans can demonstrate lumbar spinal stenosis, patients may or may not have related symptoms. Because there is no evidence to support the superiority of surgery vs non-surgical therapies for lumbar spinal stenosis, an interprofessional approach is required.