Definition
Lumbar stenosis is a narrowing of the vertebral canal diameter at the lumbosacral spine. The alterations of the column that derive from this process can exert pressure on the nerve roots, before they escape from the intervertebral foramina, causing pain. This pathological condition is mainly acquired, but it can be, even if very rarely, also congenital.
Lumbar stenosis is a common cause of sciatica in middle-aged and elderly patients, in which, in some ways, the process can be considered almost physiological: the size and shape of the vertebral canal, in fact, tend to undergo some variations with aging. These changes are more pronounced in people who carry out work that puts their back on excessive effort and are overweight.
The most common causes of acquired lumbar stenosis are osteoarthritis, degenerative disc disorders and spondylolisthesis (ie a vertebra slides forward with respect to the one below), with compression of the cauda equina.
Additional diseases of the spine that predispose to narrowing of the vertebral canal include Paget's disease of bone, rheumatoid arthritis, ankylosing spondylitis and scoliosis of the lumbar spine.
Most common symptoms and signs *
- cruralgia
- Tingling in the legs
- Sore legs
- Hypoaesthesia
- weakness
- Backache
- Paresthesia
- Sciatica
- Spinal stenosis
Further indications
Lumbar stenosis causes pain in the back (localized, in particular, in terms of shrinkage) and symptoms due to the compression of one or more nerve roots, including tingling and / or numbness (paresthesia), hyposthenia (loss of strength) of the limbs inferior and reduction of the reflexes along the course of the interested segment.
Patients can also report a pain radiating from the lumbar tract to the buttocks, to the back of the thighs or to the calves during walking, when climbing stairs or simply standing. Lumbar spinal stenosis is typically relieved when the torso is flexed forward or sits down (although the paresthesias may be constant). Rarely, spinal cord compression can cause cauda equina syndrome.
As for the diagnosis, lumbar stenosis is suspected based on characteristic symptoms. If neurological deficits are present, imaging studies and neurophysiological tests must be performed to confirm the presence and degree of involvement of the spinal root. Structural anomalies are diagnosed with greater accuracy through computerized axial tomography (CT) and nuclear magnetic resonance (NMR).
Spinal stenosis can be treated temporarily with painkillers and anti-inflammatory drugs, corticosteroid injections, rest and physiotherapy. In the more advanced cases, instead, it is necessary a surgical intervention that foresees the "decompression" of the channel through the pre-established removal of portions of vertebrae, of ligaments and / or protruded disks, to return to the structures contained in it the adequate space and alleviate symptoms such as tingling and weakness. The procedure is completed with the stabilization of the spine, using bone grafts, metal plates and screws, to create a bond between two or more adjacent vertebrae.
Alternatively, it is possible to use a fixed implant (called "interspinous spacer") positioned with a minimally invasive surgical procedure. This device keeps the space between the spinous processes open, so the spinal nerves coming out of the column are not compressed and do not cause pain.
