Goal of the Study?
Lumbar spinal stenosis affects approximately 11% of the population, primarily in the adult population.1 In this article, the authors worked to provide a clinical update giving practitioners a “what you need to know” perspective on the ins and outs of clinical practice.
Why are they doing this study?
Because of its prevalence and challenge to accurately diagnose, it is important to understand the clinical presentation of lumbar spinal stenosis from a symptomatology standpoint. This careful attention to a patient’s symptoms can help guide an appropriate care plan. The clinical challenge can be cloudy as other conditions like vascular claudication can lead even the best clinicians down the wrong diagnostic path.
What was done?
A review of the anatomy is important when understanding the clinical symptoms of lumbar spinal stenosis. In this clinical update, the authors revisit the degenerative changes of the spinal canal and the intervertebral foramen related to spacing and the nerves that travel through these spaces.
What did they find?
As the discs lose height, the associated anatomical changes can lead to narrowing. Degenerative discs lose height over time, and in doing so, the facets approximate, leading to hypertrophy of the bony architecture. Facet arthropathy (as seen in the Lumbar Spinal Stenosis Dynamic Disc Model) can take up valuable spinal real estate for lateral recess and intervertebral foramen; furthermore, discs lose height, discs bulge. And with this bulging, just as a tire bulges when it loses air pressure, it can often take up spinal canal spacing. This can also lead to the ligamentum flavum bulging itself (also thought of as buckling or thickening), encroaching on the valuable room the vasculature around the cauda equina must have to function.
The classic presentation is the patient reporting of not being able to distance walk as they have previously. They also report that standing often generates lower leg symptoms or buttock/leg weakness and relief of these symptoms by sitting and/or using the upper extremities to offload and flex the spine, like that seen with the shopping cart posture.
The authors point out that lateral recess stenosis and foraminal stenosis can mimic radiculopathy as seen in sciatica related to a disc herniation and report that a combination of these symptoms and subtypes is common.
How is Lumbar Spinal Stenosis Diagnosed?
A careful history and examination are at the roots of a proper diagnosis. Imaging has been relatively unreliable and likely due to the static nature of MRI and CT. It is suggested that clinicians can ask suspected patients to walk or to have patients extend the lumbar spine for thirty seconds to recreate the symptoms.
The authors have created these points and to be mindful of patients over 50 present with these symptoms:
- pain in lower extremities/buttocks while walking
- flexion to relieve
- relief if using the upper extremities to push down and generate lumbar flexion like that seen using a shopping cart or riding a bicycle
- unsteady motor disturbance while walking
- tingling or numbness in the legs while walking
- pulses equal and bilateral in lower extremities
- low back pain
How do Clinicians Talk about Lumbar Spinal Stenosis with their patients?