This is a very common condition especially in older people due to ‘wear and tear’.
Facet joints tend to get larger as they degenerate. This process is the body’s attempt to decrease the stress per unit area across a degenerated joint. Unfortunately, as the joint enlarges, it can place pressure on the nerves as they exit the spine
Standing upright further decreases the space available for the nerve roots, and can block the outflow of blood from around the nerve. Congested blood then irritates the nerve and cause the pain.
Some people have a constitutionally narrow spinal canal i.e. the space for the nerves is very limited and even a small slipped disc can pinch the nerves and cause pain.
When a person rises from lying down to standing, the resulting load on the intervertebral disc causes further bulging of the disc, which in turn further compromises the central canal and the foramen.
The foramina decrease in size while the nerve roots increase in diameter as you move down the spine. Thus the lumbar spine is most commonly affected.
Narrowing of the central canal and/or intervertebral foramina is due to a bulging disc, enlargement of the facet joints or simply thickening of ligaments.
Virtually all individuals in their seventies have at least some degree of spinal stenosis on imaging studies, but only a fraction manifest the true symptoms of central and/or foraminal stenosis. Typically, patients with lumbar spinal stenosis have a long history of pain in the back, buttocks, and/or legs that gradually worsens over time. Standing or walking upright usually increases the symptoms, resulting in an achy pain, tightness, heaviness, and a sense of weakness in the buttocks and/or legs. These symptoms are generally relieved by sitting down or leaning forward as this increases the space around the nerves.
Although patients with lumbar spinal stenosis are unable to walk for long periods of time, they may be able to ride an exercise bicycle for much longer. Some patients also find that it is easier to walk while leaning forward on a shopping cart. This position tends to create more space in the spinal canal and can relieve some of the pressure on the nerves. Leaning on the handlebars of a bicycle creates the same effect
Spinal stenosis may cause unsteadiness or difficulty with balance and even urinary symptoms. Typically though it is pain in the distribution of a nerve commonly on the side of the leg which improves on resting or leaning forward
Physical examination can be unimpressive in patients with spinal stenosis.
It is important to make sure the patient does not have underlying vascular problems
MRI: (without gadolinium)
Nerve root block:
The commonest reason is pain especially in the legs on walking. A claudication distance of less than 300 yards is a common guide to decide on surgery.
The X stop procedure
The PEEK implant treats lumbar spinal stenosis by increasing the space around the nerves and the spinal cord.
The X STOP® Interspinous Process Decompression System implant is inserted through a small incision in a patient's back. It separates the ligaments and bone, which prevents pressure on nerves and immediately relieves pain. The procedure takes less than one hour and typically requires a brief general anaesthetic. Many patients are able to stand upright and walk the same day of the surgery.
This is a fairly new procedure and longer term results are not yet known.
The surgical procedure is relatively minor and does not require removal of bone or soft tissue. There is no real risk to the dura or the nerve roots of the spinal canal.
The surgical procedure for lumbar spinal stenosis involves removing the bone and soft tissues of the spine that are pinching the nerves. This procedure is called a "decompression" .
Some patients with lumbar spinal stenosis require only a decompression. However, if there is also forward slippage of a vertebra or curvature of the spine, a "spinal fusion" may be needed. In this procedure, two or more vertebrae are permanently fused together, using a bone graft harvested from the hip.
Fusion eliminates motion between vertebrae and prevents the slippage or curvature of the spine from worsening after surgery, which would cause more back and/or leg pain. The surgeon may use screws and rods to hold the spine in place while the bones fuse together.
The use of rods and screws makes the fusion of the bones happen faster and speeds postoperative rehabilitation. Overall, the results of spinal fusion are good to excellent in approximately 80% of patients. Patients tend to see more improvement of leg pain than back pain. Most patients are able to resume a normal lifestyle after a period of recovery from surgery.
There are some risks to surgery for lumbar spinal stenosis. About 20 % of patients may not benefit from surgery especially if the nerves have been compressed for a long time. In people who have very tightly squashed nerves, there is a risk of damage to the nerves or more commonly a CSF leak where the fluid surrounding the nerves and enclosed in a thin membrane leaks out. This can usually be repaired or patched up, but risk of a re-leak may require further surgery. Very rarely more serious neurological complications such as complete paralysis may be seen. There are also risks of an anaesthetic and surgery at an older age such as developing a pneumonia etc.
Elderly patients have higher rates of complications from surgery. So do overweight patients, diabetics, smokers, and patients with multiple medical problems.
After surgery, patients may be hospitalized for 1 to 4 days depending on the extent of surgery performed.
Relatively healthy patients who undergo only decompression may be discharged from the hospital the same day, and may return to normal activities after only a few weeks.
Patients who undergo spinal fusion are hospitalized for several days. They usually receive an outpatient physical therapy program.
A lumbar corset or brace may also be prescribed after surgery. Patients generally return to normal activities after 2 to 3 months.
Older patients who need more physical therapy may be transferred from the hospital to a rehabilitation facility.
The best way to avoid lumbar spinal stenosis is to stay as physically fit as possible. Regular exercise can improve endurance and keep the muscles that support the spine strong.
Avoiding weight gain can decrease the load that the lumbar spine has to carry.
Patients should also avoid cigarette smoking. Both the smoke and the nicotine cause the spine to degenerate faster than normal.