What is stenosis? It is an abnormal narrowing of a passage in the body. This can include, constriction of a blood vessel, valve, spinal canal or intervertebral foramen (IVF). The narrowing of the spinal canal and IVF typically occurs following degeneration of the intervertebral disc. Almost all people who receive imaging at age 50+ will show evidence of spinal stenosis, but not all will have symptoms. Symptoms vary depending on the location and severity of the stenosis. If the stenosis occurs at one spinal level in one region with mild constriction, symptoms may be intermittent and less severe.
Symptoms of Lumbar stenosis:
- Numbness or tingling in a foot or leg
- Weakness in a foot or leg
- Pain or cramping in one or both legs when you stand for long periods of time or when you walk, which usually eases when you bend forward or sit
- Back pain
- incontinence
- balance problems
Causes of Lumbar Stenosis:
The primary cause of lumbar stenosis is osteoarthritis/ degenerative disc disease. Between each boney vertebra is a spinal disc which acts as a cushion/ hydraulic pump. The young healthy disc is likened to a fresh jelly donut with a fibrous outer layer and gelatinous inside. The disc acts like a hydraulic pump by increasing and decreasing water content with changes in load. For example, at night when sleeping a healthy disc imbibes water to expand the disc, with load and movement throughout the day will decrease water content. The healthy disc hydrates and rehydrates throughout the day depending on load and activity. An aged disc (>50 y/o) is like a jelly donut that has been sitting on the counter for a few days or more. It is firmer, flatter and has less water content. An aged disc doesn’t always equal an unhealthy spine. What happens with a flattened disc is that there is more load to the facet joints on the sides of the vertebrae.
Intervertebral Foramina Stenosis
The increased load will cause formation of bone spurs that can take up space in the IVF or cause the spinal nerve in the IVF to travel further and reduce blood flow. The spinal nerve root has to travel a further distance with a flattened disc and the increased tension on the spinal nerve root reduces blood flow. It is like pulling a garden hose around the corner of the house to water flowers in the back yard, the tension on the hose reduces the flow of water. With the increased load to the lumbar facets, osteoarthritis can occur and the development of synovial cysts. The cysts occur as a result of load and arthritis and can become a space occupying lesion in the IVF.
Radiculopathy is the sequelae to IVF narrowing. A radiculopathy is a referred pain, weakness, sensory change from an effected nerve root.
Central Canal Stenosis
The spinal canal can also become narrowed with the changes of ligaments (ligamentum flavum) that help hold the spine together. Over time these ligaments become stiff and thickened which can reduce the diameter of the spinal canal. The spinal canal in the lumbar spine contains the cauda equina, which is comprised of 10 pairs of spinal nerves which are responsible for sensory and motor (strength) innervation to the pelvis and lower limbs, as well as bowel and bladder function.
Neurologic symptoms such as claudication associated with spinal stenosis occur most commonly as a result of reduced blood flow to nerve roots or mechanical compression of nerve roots.
Narrowing of the spinal canal can lead to mechanical compression of the nerve roots and cause venous congestion. Multiple spinal levels might be narrowed to produce symptoms of reduced conduction to the nerve roots (sensory and motor loss).
Symptoms of spinal stenosis are caused by and become most prominent when there is a reduction of space in the joints; this occurs naturally with prolonged standing when the spine is in an erect position. Extension of the spine causes the overlapping of facet joints, with resultant relaxation and inward buckling of the ligamental flavum. Walking may additionally exacerbate symptoms as the increase in oxygen demands of the spinal nerve roots may exceed the available blood flow, and worsened with multilevel venous congestion.
Treatment of Stenosis
The Wayne
One of the most important goals of treatment is to increase blood flow to spinal nerve roots whether in the central canal or IVF.
- Nerves do not respond well to reduced blood flow and oxygenation, the result is pain, paresthesias (tingling), numbness and motor (strength) loss. Functionally, this can reduce the ability to move and walk and increase risk factors for other disease processes. The position of the body is very important: standing up straight will reduce the blood flow to the spinal nerve roots by reducing space in the spinal canal and IVF. Do not bend backwards or perform stretching into extension (ie: cobra position) or lay flat on back. Do support hips and knees when laying on back, perform knee to chest stretching, flexion based exercises, walk with walker or trekking poles and allow yourself to slouch a little. Flexion (slouch) opens up the space for the spinal nerves slightly, which helps increase blood flow.
- Epidural Steroid Injection (ESI): to reduce inflammatory cells and venous congestion, which in turn will increase blood flow and healing response to the spinal nerves. The injection can be performed in a caudal orientation for a general approach or a selective approach to a specific nerve root level. This will be a decision made by your health care provider.
- Low load cyclic exercise in a flexion position: Pool exercise is a great way to achieve this with an aquatic float to run or walk in pool and perform general strength exercises. The unweighted environment of the pool is usually far less painful and you will be able to move in a functional way and therefore improve blood flow and healing response. If no access to a pool, use trekking poles to walk short distances frequently throughout the day ie: 5 min walks 5x daily. Make sure the poles are a little lower than normal to allow yourself to flex forward and use your arms to unweight the load of your back. Walking up a slight hill is great, but get a ride back down.
- Flexion exercises: lay on back and gently bring knees to chest, you can do one at a time or together as long as there is not a big increase in symptoms. This exercise should feel good, if it doesn’t adjust your position. (POSITION MATTERS). If you are unable to lay on your back, sit in a comfortable chair and lift knee to chest, one at a time, alternating sides. In addition you can flex body over table or countertop with pillows under stomach and let legs hang underneath your body. All of these exercises should be done at least 2-3x daily. I would suggest doing them for time for 5 min total. The hanging exercise should be done intermittently for 1 min intervals.
- Sleep position: Again position matters, not to sound like a broken record. I often suggest having people sleep with a body pillow, that way you can accommodate multiple sleep positions. One position I never recommend in stomach sleeping, it is a bad position for the spine in general and specifically bad for those with stenosis. If you are a back sleeper, use pillow to prop up hips and knees into flexion position. Use the pillow in front of body and between knees with fetal type position. The pillow protects you from rolling forward and rotating your spine. Rotation is a pain provoking for stenosis as it loads the facet joints. You can also place the pillow behind your spine so that you do not roll backwards. You will need restful sleep for healing and recovery.
- Use heat: hot tub, hot shower, sauna, hot pack on entire low back. I would suggest doing this frequently daily, stacking the odds in your favor for increased blood flow and healing.
- Massage in a flexion position: Do not lay flat on your stomach, this defeats the whole purpose of increasing blood flow. I would suggest pillows under stomach into flexion, or my favorite treatment position is side lying with knees flexed up and supported with pillow between knees.
- TENS unit : This helps increase blood flow and reduce pain while using it. You can get an inexpensive unit online, you do not need anything fancy. If you have questions what to get, send me a message. Use this at least for one hour daily, you can use it all day while awake if you like. You need to feel a sensory level stimulation for improved effectiveness. I suggest placing the electrodes two per side of spine at lower rib cage. Usually this is not where you have pain, but this is a great place to increase blood flow. You can use it at site of pain also; however, rarely in the spine is the pain where the source of pain is located.
- See a good manual physical therapist: for manual hip mobilization. I always say that stiff hips are a great opportunity to reduce pain when suffering with spinal stenosis. Treatment is focused on improving hip extension while protecting the low back from extending. Treatment position of choice in side lying on both sides. The treatment should not be painful, if it is position needs to be adjusted and low back protected from extension. 2x a week for a month is great to improve mobility and reduce pain
- Walk with shortened stride: Long stride will put an extension load through the low back. This might seem silly, but this really helps.
- low load traction: to stretch the ligamentum flavum to increase central canal space. This can be done by a therapist and also can be done at home with a specific traction unit. Inversion tables do not work well for spinal stenosis as they tend to reduce space in the central canal with extension position
- Facet joint injections/ablation procedures: If the facet joints are the source of pain, selective injections into the joints can help reduce pain and improve function.
You will need to do more than 1-2 of these things to see good results. It is worthwhile and doing just one or two of these things will not necessarily make a huge difference, but doing all will stack the odds in your favor. Your health care provider can guide you with injection management and if you are a candidate for this specific program.
