Generally speaking, the various types of spinal stenosis produce similar symptoms. Leg pain (sciatica) often with some low back pain, leg numbness and tingling, with limitations, in walking are together the most common symptoms of lumbar spinal stenosis.
Leg pain with walking (claudication) can be caused by either arterial circulatory insufficiency (vascular claudication) or from spinal stenosis (neurogenic or pseudo-claudication). Leg pain from either condition will go away with rest, but with spinal stenosis the patient usually has to sit down for a few minutes to ease the leg and often low back pain, whereas leg pain from vascular claudication will go away if the patient simply stops walking.
Although occasionally the symptoms and leg pain from spinal stenosis will come on acutely, they generally develop over the course of several years. The longer a patient with spinal stenosis stands or walks the worse the leg pain will get.
Flexing forward or sitting will open up the spinal canal and relieve the leg pain and other symptoms, but they recur if the patient gets back into an upright posture. Numbness and tingling can accompany the pain, but true weakness is a rare symptom of spinal stenosis. An older person leaning over the handle of their shopping cart while making short stumbling steps often has spinal stenosis.
Overall, the symptoms of lumbar spinal stenosis are often characterized as follows:
Diagnostic imaging studies for spinal stenosis patients include either an MRI scan or a CT scan with myelogram (using an x-ray dye in the spinal sack fluid), and sometimes both. Unenhanced or plain CT scans are of limited value unless made with very fine segmental scan slices.
It can be shown that each form of spinal stenosis has a dynamic (changing) effect on nerve compression, such as when bearing weight. Due to this changing compression, the symptoms of spinal stenosis vary from time to time and the physical examination generally will not show any neurological deficits or motor weakness. Some recent scanning methods allow the upright body position to study the effects of spinal loading.
Foraminal stenosis can be pinpointed not only by the CT and MRI scans, but also by injecting the suspicious nerve with a small volume of about 2 dozen drops of local anesthetic (selective nerve root block). After the injection a remission of spinal stenosis symptoms when walking, along with true temporary weakness of the limb, is clinically diagnostic and helps the patient to decide about surgery.
Since a spinal stenosis at two or even three levels (sub-laminar, foraminal and far lateral) can affect a single emerging nerve, a combination of anatomical and clinical clarification is needed if surgery is contemplated in order to make sure that one surgical procedure will address all contributing components of that particular case.
