Neurogenic claudication (NC) is a medical condition characterized by discomfort, pain, or weakness in the legs that occurs when a person is walking or standing upright. The term is derived from “neurogenic,” indicating an origin in the nervous system, and the Latin word “claudicare,” meaning “to limp.” This intermittent leg pain is common among older adults and affects the lower back and legs. NC symptoms are directly related to posture and activity, frequently interfering with daily activities like walking or standing for extended periods.
Distinguishing Neurogenic from Vascular Claudication
Neurogenic claudication (NC) is often confused with vascular claudication (VC) because both cause leg pain with activity, but their underlying mechanisms are entirely different. NC stems from the compression of spinal nerves, whereas VC is caused by insufficient blood flow to the muscles in the legs, a symptom of peripheral artery disease (PAD).
The primary distinguishing factor is the effect of posture on the symptoms. With NC, the pain is provoked by standing or extending the spine backward, and it is quickly relieved by bending forward or sitting down, which temporarily widens the spinal canal. In contrast, VC is purely activity-dependent; the pain is brought on by exercise and relieved simply by stopping the activity and resting, regardless of body position. Furthermore, VC pain usually starts in the calves, while NC often affects the buttocks and thighs first.
The Underlying Cause: Lumbar Spinal Stenosis
Neurogenic claudication is the most common clinical feature of lumbar spinal stenosis (LSS). Spinal stenosis describes the narrowing of the spinal canal in the lower back, which houses the spinal cord and nerve roots. This constriction reduces the space available for the nerves, leading to their compression and subsequent symptoms.
The narrowing is primarily a result of age-related degenerative changes. Over time, the intervertebral discs lose water content and height, causing them to bulge outward and reduce the canal space. Concurrently, the facet joints develop arthritis, leading to the formation of bone spurs (osteophytes) that encroach upon the nerve openings.
The ligaments supporting the spine, particularly the ligamentum flavum, can also thicken and buckle into the spinal canal. These combined structural changes—bulging discs, arthritic facet joints, and thickened ligaments—physically compress the lumbar nerve roots. The resulting pressure on the nerves disrupts their function, leading to the pain, tingling, and weakness experienced in the legs.
Recognizable Symptoms and Presentation
Neurogenic claudication follows a classic and predictable pattern. Primary symptoms include pain, cramping, tingling, or weakness that radiates into the buttocks, thighs, and calves, sometimes affecting one or both legs. These symptoms are reliably triggered by activities that cause the spine to extend or straighten, such as prolonged standing or walking, especially when walking downhill.
A hallmark sign of NC is the immediate relief of symptoms upon changing posture to a flexed position. Sitting down, squatting, or leaning forward, such as over a shopping cart or a walker, allows the spinal canal to slightly open up, relieving the pressure on the compressed nerves. This phenomenon is often called the “shopping cart sign.” Patients often report that they can ride a stationary bike without pain because the forward-flexed posture keeps the spinal canal decompressed.
Diagnosis and Management Approaches
Diagnosis begins with a detailed physical examination and a thorough review of the patient’s symptoms and medical history. The physician looks for the classic positional nature of the pain—worsening with extension and relief with flexion—to differentiate it from vascular causes. Imaging tests are then used to confirm the presence and severity of the underlying lumbar spinal stenosis.
Magnetic Resonance Imaging (MRI) is the preferred imaging modality because it provides detailed pictures of the soft tissues, allowing doctors to visualize the compressed nerve roots, bulging discs, and thickened ligaments. Computed Tomography (CT) scans may also be used, particularly if an MRI is contraindicated, to assess the bony structures of the spine. Ruling out vascular claudication often involves separate tests, such as the ankle-brachial index, to check blood flow in the legs.
Management typically starts with conservative, non-surgical approaches.
Conservative Treatments
Physical therapy is a primary treatment, focusing on exercises that strengthen the core muscles and promote a slightly flexed posture to reduce nerve compression. Medications, including non-steroidal anti-inflammatory drugs (NSAIDs), are used to manage pain and inflammation. Epidural steroid injections, which deliver anti-inflammatory medication directly to the area around the compressed nerves, can offer temporary relief.
Surgical Intervention
When conservative treatments fail to provide adequate relief for severe, life-limiting symptoms, surgical intervention may be considered. The most common surgical procedure is decompression surgery, such as a laminectomy, which involves removing a portion of the bone and tissue that is pressing on the nerves to create more space in the spinal canal.