Spinal stenosis is a common condition characterized by a narrowing of the spinal canal.
The severity of the presentation differs from person to person depending on the body type. Size of the spinal canal does not affect the symptoms. Patients with spinal stenosis present with a chronic back pain. The symptoms vary with the location of the stenosis. However, pain, motor weakness, paresthesia and numbness of the lower limbs are the associated common symptoms.
Stenosis in the lumbar spine results in lumbago with radiculopathy. Urinary incontinence and loss over rectal control is seen in severe cases of spinal stenosis. Classical symptoms of lumbar stenosis include bilateral neurologic claudication.
Patients experience diffuse pain in the lower extremity which is intermittent and accompanied with paresthesiae. In a study conducted on 75 patients, it was observed that numbness, radiculopathy and neurologic claudication were present throughout in equal intensity. Neurologic claudication is aggravated with prolonged standing and descending and is relieved with elevation of extremity or by lying in a supine position .
The compensatory changes that develop eventually in patients of lumbar stenosis are leaning on to objects, posture changes like forward bending and slowing of gait.
Stenosis in the cervical spine results in a syndrome called cervical spondylotic myelopathy. Symptomatically there is proximal upper extremity weakness with loss of upper arm power. Later it may progress to ataxia due to compression of the spinocerebellar tracts.
Patients may also develop paresthesiae, weakness, upper arm radiculopathy and depressed reflexes depending on the level of nerve root impingement. In cases where there is inflammation of the ligamentum flavum or at the facetal joint capsule, the presentation may be asymptomatic as there is no nerve root compression. Such cases only show radiologic changes. In cases of metastasis of spine, the regional pain is present due to nerve root compression along with canal stenosis.
MRI and CT scans remain the standard scanning procedures in order to study the site and extent of the spinal stenosis. MRI scans helps in viewing the spinal structure, bones, vessels and muscular ligaments, while CT scans provide information about the central canal, lateral recess, and the vertebral foraminae  .
Angiography is rarely indicated and is done only in suspected cases of vascular malformations. Neuronal studies include needle electromyography which detects lumbosacral radiculopathy along with axonal loss. Nerve conduction studies are done to helps to rule out neuropathies like peripheral neuropathy, tarsal tunnel syndrome etc. .
The aim to treatment of spinal stenosis is pain management and limiting the further disability. Non-surgical treatment includes analgesics, anti inflammatory agents and anti spasmodic, along with this physical therapy such as traction, exercises to strengthen muscles helps to reduce pressure and improves mobility.
Surgery includes lumbar decompressive laminectomy in which the nerves are decompressed by removing the roof of the vertebrae overlying the thickened ligaments. After this an interlaminal implant is placed between the two bones to in order to stabilize the joints  .
For neuropathic pain, tricyclic antidepressants are given but are not highly recommended due to their adverse effects especially in elderly age group. The radicular pain from the lateral recess stenosis is relieved by membrane–stabilizing anticonvulsants such as gabapentin and caramazepine. In patients not responding to medications and other physical therapies, epidural steroid injection provides relief.
Patients undergoing surgery get good relief from the pressure symptoms as the compression of the affected nerve root gets released. Spinal stenosis results in morbidity more than mortality. This condition often causes disability and chronic pain rather than death. In individuals with spinal canal stenosis, the anterior cord compression causes a central spinal cord syndrome, likewise, a posterior cord compression causes partial dorsal column syndrome.
The spinal stenosis at the cervical or the thoracic region leads to compression symptoms leading to myelopathy and weakness in the lower extremity along with difficulty in maintain gait. In individuals with lumbar spinal stenosis, a study showed that about 90% of 169 patients showed symptomatic relief over the period of two years without undertaking any treatment. In another study of 32 patients suffering from moderate stenosis, no symptomatic change was observed in 70% of them despite taking conservative treatment for 4 years, while 15% showed improvement .
Spinal stenosis occurring congenitally is due to segmentation failure, achondroplasia or due to incomplete closure of the vertebral arch. Developmental anomalies include early vertebral arch ossification, vertebral wedging, osseous exostosis and thoracolumbar kyphosis.
Acquired causes include trauma, degeneration changes due to disc prolapsed, ligamentum flavum hypertrophy and spodylolisthesis.
It is estimated that about 250,000 to 500,000 US residents have been suffering from the symptoms of spinal stenosis. This represents that spinal stenosis accounts to be a major health issue in the United States. About 1 in 1000 of the population in the age group older to 65 years suffers from this condition. It is more prevalent in the older age group. Of these, there are about 35% patients who are asymptomatic.
Lower lumbar spine is more prone to foraminal stenosis as the diameter of the dorsal root ganglion is larger than that of the foramen.
Among the Asians, cervical stenosis is more common. This is due to the ossification of the posterior longitudinal ligament. The longitudinal Framingham heart study recorded degenerative slip disc syndrome in about 1% of men and 1.5% female above the age group of 54. A Swedish study revealed 5 of 100,000 residents developed spinal stenosis with the canal diameter 11mm or less .
The spinal canal comprises of the spinal cord, cerebrospinal fluid and the dural membranes which capsules the cerebrospinal fluid. The prolapse of the intervertebral discs due to degeneration or due to trauma and other mechanical factors results in narrowing of the spinal canal and the lateral recesses. Along with the narrowing of the spinal canal, the other changes observed are, thickening of the posterior longitudinal ligament, and hypertrophy of the facet joints, epidural fat deposition and inflammation of the ligamentum flavum.
The degeneration leads to further subluxation of the vertebral bodies thus resulting in the spur formation. The common site for this is mainly the fifth, sixth and the seventh cervical vertebraes .
Simple measures like exercising regularly , going for daily walks, maintaining ideal body weight , maintaining a good posture and understanding one’s own body mechanics are ways to prevent back pathology. Doing regular exercises strengthens the muscles of the back and helps in shock absorbing in case sudden change of posture or trauma.
Spinal stenosis is a condition in which there is narrowing of the spinal canal. This is commonly seen in the lumbar and cervical spine. Lumbar spinal stenosis is often accompanied by nerve impingement. It includes central as well as lateral recess stenosis.
In lateral canal stenosis, as there is involvement of the nerve it results in severe radiculopathy, with muscle weakness, pain and immobility. This occurs due to a series of changes in the components of the central and lateral canal such as ligamentum flavum inflammation, bony spurs, epidural fat deposition and facetal hypertrophy .
Management of spinal stenosis includes conservative or surgical treatment. Conservative approach comprises of rest, analgesics, anti inflammatory medications, physical exercises, and weight loss. Surgery is done in patients who have severe pain, disability, neuropathy or malignancy.
Spinal stenosis occurs due to narrowing of the spinal canal. This leads to pressure to the surrounding nerves. Disc degeneration is the common cause of spinal stenosis. This leads to collapse of the disc space and compression of the facetal joints thus irritating the spinal nerves and giving rise to pain and numbness.
Treatment includes anti inflammatory drugs, pain killers, injections to relieve the numbness. Physical therapy such as traction and strengthening exercises are an important part of the overall regimen to be followed. Patients are instructed to avoid factors which can cause aggravation such as excessive lumbar extension or doing descending walks, or factors that can produce stress on the affected bone, and ligaments such lifting heavy weights they are encouraged to do more of exercises such as pilates, flexion training , gluteal strengthening, etc. .