Neurogenic claudication (NC), also known as pseudoclaudication, is the most common symptom of lumbar spinal stenosis (LSS) and describes intermittent leg pain from impingement of the nerves emanating from the spinal cord. Neurogenic means that the problem originates within the nervous system. Claudication, , refers to painful cramping or weakness in the legs. should therefore be distinguished from vascular claudication, which stems from a circulatory problem rather than a neural one.
The term neurogenic claudication is sometimes used interchangeably with spinal stenosis. However, the former is a clinical term, while the latter more specifically describes the condition of spinal narrowing. is a medical condition most commonly caused by damage and compression to the lower spinal nerve roots. It is a neurological and orthopedic condition that affects the motor nervous system of the body, specifically, the lower back, legs, hips and glutes. does not occur by itself, but rather, is associated with other underlying spinal or neurological conditions such as spinal stenosis or abnormalities and degenerative changes in the spine. The International Association for the Study of Pain defines neurogenic claudication as "pain from intermittent compression and/or ischemia of a single or multiple nerve roots within an intervertebral foramen or the central spinal canal". This definition reflects the current hypotheses for the pathophysiology of , which is thought to be related to the compression of lumbosacral nerve roots by surrounding structures, such as hypertrophied facet joints or ligamentum flavum, bone spurs, scar tissue, and bulging or herniated discs.
The predominant symptoms of involve one or both legs and usually presents as some combination of tingling, cramping discomfort, pain, numbness, or weakness in the lower back, calves, glutes, and thighs and is precipitated by walking and prolonged standing. However, the symptoms vary depending on the severity and cause of the condition. Lighter symptoms include pain or heaviness in the legs, hips, glutes and lower back, post-exercise. Mild to severe symptoms include prolonged constant pain, tiredness and discomfort in the lower half of the body. In severe cases, impaired motor function and ability in the lower body can be observed, and bowel or bladder dysfunction may be present. Classically, the symptoms and pain of are relieved by a change in position or flexion of the waist. Therefore, patients with have less disability in climbing steps, pushing carts, and cycling.
Treatment options for depends on the severity and cause of the condition, and may be nonsurgical or surgical. Nonsurgical interventions include drugs, physical therapy, and spinal injections. Spinal decompression is the main surgical intervention and is the most common back surgery in patients over 65. Other forms of surgical procedures include: laminectomy, microdiscectomy and laminoplasty. Patients with minor symptoms are usually advised to undergo physical therapy, such as stretching and strengthening exercises. In patients with more severe symptoms, medications such as pain relievers and steroids are prescribed in conjunction with physical therapy. Surgical treatments are predominantly used to relieve pressure on the spinal nerve roots and are used when nonsurgical interventions are ineffective or show no effective progress.
Diagnosis of neurogenic claudication is based on typical clinical features, the physical exam, and findings of spinal stenosis on computer tomography (CT) or X-ray imaging. In addition to vascular claudication, diseases affecting the spine and musculoskeletal system should be considered in the differential diagnosis.
Signs and symptoms Neurogenic claudication commonly describes pain, weakness, fatigue, tingling, heaviness and paresthesias that extend into the lower extremities. These symptoms may involve only one leg, but they usually involve both. Leg pain is usually more significant than back pain in individuals who have both. is classically distinguished by symptoms improving or worsening with certain activities and manoeuvres. Pain may occur with walking, standing, and back extension. Sitting and bending or leaning forward tend to provide relief. Patients may also report that pain is worse while walking down stairs and improved while walking up stairs or using a bicycle or shopping cart. A positive "shopping cart sign" refers to the worsening of pain with spinal extension and improvement with spinal flexion.
Whilst these common symptoms are usually present in many patients with , rarer and more serious symptoms can occur in severe cases of . In extreme cases of constant discomfort, pain or numbness is experienced. This results in patients to have decreased mobility and function as excessive or constant movements cause pain. Exercise and prolonged walking often become difficult and are triggers of pain, tiredness, numbness and heaviness in the legs, lower back and hips. Common tasks such as standing upright for an extended duration or picking up heavy objects may become increasingly difficult to perform. In addition, patients with severe may experience difficulties sleeping as lying down on their back causes discomfort and pain. In very extreme cases, bowel or bladder dysfunction can occur. However, this is a consequence of the underlying cause of rather than the condition itself. As most causes of involve increased pressure or damage to the nerves in the lower spine, damage and pressure on the nerves that extend to the bowel or bladder may occur, leading to bowel or bladder dysfunction.
On physical examination, patients with have normal peripheral pulses. The neurologic exam, straight leg raise, and femoral nerve stretch are typically normal. Abnormal signs may be revealed if the patient is observed walking until they exhibit . For example, a positive "stoop test" is observed if bending forward or stooping while walking relieves symptoms. Occasionally, patients may have other signs such as sensory loss or gait changes.
Causes Neurogenic claudication is the fundamental clinical feature of , which may be congenital or acquired. As a result of , the spinal canal in the lumbar spine narrows, causing damage and arthritic changes in the spine. These changes, such as bulging disks, thickening of ligaments and overgrowth of bone spurs, lead to pressure and potentially damage to the spinal nerve roots. The compression of the spinal nerve roots that control movements and sensations in the lower body subsequently causes the symptoms of . The causes of are most commonly acquired and include degenerative changes such as degenerative disc disease and spinal osteoarthritis. may also be acquired from changes due to spinal surgery such as excess scar tissue or bone formation. Other secondary causes include space-occupying lesions, ankylosing spondylitis, rheumatoid arthritis, and Paget's disease. Less commonly, the cause of spinal stenosis may be present at birth as seen in achondroplasia, spina bifida, and certain mucopolysaccharidoses. In addition to spinal stenosis, other lower back conditions such as spondylosis, tumors, infections and herniated or ruptured discs can cause . These conditions contribute to the potential narrowing of the spinal cord, increasing pressure and inducing damage on the spinal nerve roots, thus, causing paing, tingling or weakness in the lower body.
Risk factors for include:
Age Degenerative changes of the spine Obesity Family history of spinal stenosis Tobacco use Occupation involving repetitive mechanical stress on the spine Past deformities or injuries to the spine
Diagnosis and evaluation
Neurogenic claudication is one subtype of the clinical syndrome of lumbar spinal stenosis (LSS). No gold standard diagnostic criteria currently exist, but evaluation and diagnosis is generally based on the patient history, physical exam, and medical imaging. The accuracy of a diagnosis of increases with each additional suggestive clinical finding. Therefore, a combination of signs and symptoms may be more helpful in diagnosing NC than any single feature of the history or physical exam. These signs and symptoms include pain triggered by standing, pain relieved by sitting, symptoms above the knees, and a positive "shopping cart sign".
Specific questions that may aid diagnosis include:
"Does the patient have leg or buttock pain while walking?" "Does the patient flex forward to relieve symptoms?" "Does patient feel relief when using a shopping cart or bicycle?" "Does the patient have motor or sensory disturbance while walking?" "Are the pulses in the foot present and symmetric?" "Does the patient have lower extremity weakness?" "Does the patient have low back pain?" The physical exam may include observation, evaluation of pulses in the foot, lumbar spine range of motion, and components of a neurological exam.
Helpful imaging may include x-rays, CT, CT myelogram, and magnetic resonance imaging (MRI), but MRI is preferred. Abnormal MRI findings may be present in two-thirds of asymptomatic individuals, and imaging findings of spinal stenosis do not correlate well with symptom severity. Therefore, imaging findings must be considered in the context of a patient's history and physical exam when seeking a diagnosis. The evidence for using objective imaging findings to define has been conflicting.
Differential diagnosis Neurogenic claudication must be differentiated from other causes of leg pain, which may be present in a number of conditions involving the spine and musculoskeletal system. The differential diagnosis for includes:
Vascular claudication Lumbosacral radicular pain secondary to lumbar disc herniation Referred pain from spinal structures, hip or sacroiliac joint, myofascia, or viscera Trochanteric bursitis Piriformis syndrome Muscle pain Vertebral compression fracture Compartment syndrome Peripheral neuropathy
Neurogenic vs vascular claudication +Neurogenic vs Vascular ClaudicationClinical featureNeurogenicVascularPain worse withStanding, walkingWalkingPain relieved bySpinal flexion, sittingStandingTiming of reliefWithin minutesImmediatelyLocationAbove the kneesBelow the kneesRadiation of painExtends down legsExtends up legsQuality of painSharpCramping, dullBack painCommonSometimesPeripheral pulsesPresentMay be absent Both neurogenic claudication and vascular claudication manifest as leg pain with walking, but several key features help distinguish between these conditions. In contrast to , vascular claudication does not vary with changes in posture. Patients with vascular claudication may experience relief with standing, which may provoke symptoms in . The walking distance necessary to produce pain in vascular claudication is more consistent than in neurogenic claudication.
Pathophysiology
Degenerative disc disease (DDD) may trigger the pathogenesis of neurogenic claudication. When intervertebral discs degenerate and change shape in , the normal movements of the spine are interrupted. This results in spinal instability and more degenerative changes in spinal structures including facet joints, ligamentum flavum, and intervertebral discs. These pathologic changes result in narrowing of the vertebral canal and neurovascular compression at the lumbosacral nerve roots. The compression of these spinal nerve roots that control sensation and movement in the lower body results in the tingling, pain and weakness patients often experience. However, because the severity of symptoms does not correlate well with the degree of stenosis and nerve root compression, a clear understanding of the specific pathogenesis remains challenging.