20 I Fall 2018 www.anjc.info TECHNIQUE Council A 70-year-old male presents to your clinic complaining of worsening back pain and lower extremity pain, numbness, heaviness and weakness. He was a regular walker, walking up to 4 kilometers per day and now he cannot walk more than half a block and has to sit down for relief. He has high blood pressure but is otherwise healthy. How would you assess and manage this patient? Degenerative lumbar spinal stenosis (DLSS) is a leading cause of pain, disability, and loss of independence in older adults. Lumbar spinal stenosis refers to a focal narrowing of the central canal and/or lateral foramina of the spine usually identified by imaging. Evidence of narrowing of the spinal canals alone without clinical information is not meaningful since 30 percent of patients over the age of 55 have moderate spinal stenosis and have no symptoms (Tong 2006). Neurogenic claudication is the term used to describe the clinical syndrome caused by lumbar spinal stenosis. It is characterized by bilateral or unilateral buttock, lower extremity pain, heavi- ness, numbness, tingling or weakness, precipitated by walking and standing and relieved by sitting and bending forward (Katz 2008, Suri 2010). There are many causes of narrowing of the spinal canals. However, by far the most common cause of spinal stenosis is degenerative arthritis. Degenerative arthritis, or osteoarthritis, is a wear and tear type of arthritis that we all get to some degree when we age. Degenerative arthritis results in thinning and bulging of the intervertebral discs, thickening of the facet joints, and infolding and thickening of the internal spinal ligaments. Degenerative spinal changes lead to a decrease in the cross sectional area of the spinal canals and potential compression to the spinal nerves that travel to the lower extremities. The narrowed spinal canals also restrict blood flow to the spinal nerves which needs oxygen to function. This leads to neuro-ischemia and hypoxia to the nerves which results in lower extremity pain and claudication (Takahashi 1995). Limited walking ability is the dominant functional impairment caused by symptomatic DLSS (Katz 2008). Those afflicted have greater walking limitations than individuals with knee or hip osteoarthritis (Winter 2010) and greater functional limitations than those with congestive heart failure, chronic obstructive lung disease or SLE (Fanuele 2000). Inability to walk among individuals with symptomatic DLSS leads to a sedentary lifestyle and a progressive decline in health status. DLSS is a chronic disease that can deteriorate with age. Reliable data on the prevalence of symptomatic DLSS is lacking. A Japa- nese study revealed that almost half of patients who present to a primary care doctor with numbness and tingling of the lower extremities have neurogenic claudication due to lumbar spinal stenosis with an average age of 65 for females and 55 for males (Konno 2007). With the rapidly aging population there will be an exponential rise in the number of people afflicted with symp- tomatic DLSS with a large associated increase use in health care resources. An interesting phenomena associated with DLSS is the dynamic nature of the symptoms. Symptoms usually are precipitated by standing and walking and the longer one stands or walks the more intense the symptoms become. However, sitting or stooping forward or lying down results in a rapid reduction or elimination of the symptoms. This is explained by the change in the cross sectional area of spinal canals with changing posture (Kanno 2012, Madsen 2008). Lumbar flexion which occurs when you sit or stoop forward increases the spinal cross sectional area and reduces spinal nerve compression and restores spinal blood supply whereas lumbar extension (we tend to maintain an lumbar lordosis when we stand and walk) decreases the cross sectional area and increases nerve pressure and symptoms. Patients with DLSS will typically describe their leg symptoms as numbness, tingling, pins and needles, weakness or heaviness in the buttock, posterior thigh and lower leg that can impact their ability to walk. Back pain can be present, but is not always, and can follow the same dynamic pattern. Using a shopping cart or walker can eliminate or relieve leg symptoms because of the forward (flexed) leaning posture. Patients may also report difficulty with balance because of the impaired lower extremity proprio- ception as a result of spinal nerve compression. Patients with DLSS are often frustrated and depressed because they are experiencing a shrinking of their world with their limited inability to walk. Physical Examination On physical examination, patients with DLSS tend to stand with a stooped posture. Range of motion testing typically demonstrates little difficulty during forward flexion, however lumbar extension is usually limited and painful and can sometime reproduce lower extremity symptoms. Lumbar extension position may have to be maintained for a period of time before leg symptoms are reproduced. Balance testing may reveal difficulty and many patients will use a cane for added security. Heel-toe walking and a standing squat may demonstrate weakness that reflects involvement of a specific nerve root(s), however, this is usually seen in more long standing DLSS. The same hold true for sensory The Management of Degenerative Lumbar Spinal Stenosis By Dr. Carlo Ammendolia