Lumbar spinal stenosis, a disease mainly affecting the middle-aged and the elderly, is caused by the gradual narrowing of the spinal canal by thickened yellow ligament, enlarged facet joints, and bulging discs.
Typically, individuals with spinal stenosis experience significant leg or calf pain, along with lower back pain, particularly after walking. Finding relief often involves sitting down or leaning forward, which creates space within the spinal canal and helps alleviate symptoms.
Since not all patients with narrow spinal canals develop symptoms, the focus in spinal stenosis is on leg pain caused by compressed nerves.
Factors that increase the risk of developing spinal stenosis include:
During clinical evaluations, it is important to rule out peripheral vascular disease (or lack of blood flow to the legs) as a possible diagnosis.
X-rays are used to confirm spinal stenosis, and MRI goes further by revealing the level, nature, and severity of spinal stenosis.
When severe or progressive nerves are not involved, the following conservative measures can be used:
In many instances, the conditions leading to spinal stenosis may not respond to non-surgical treatments, even though these measures can offer temporary relief. The decision for surgery is influenced by the effectiveness of non-surgical options, the extent of the patient's pain, and the patient's preferences.
Surgery may be considered when a patient experiences numbness or weakness impacting walking or affecting bowel or bladder function. The primary goals of surgery are to alleviate pressure on the nerves, restore spinal alignment, and maintain it through decompressive laminectomy—the removal of the lamina (roof) of one or more vertebrae.
Fusion may be recommended if the affected spinal segment is unstable (e.g., spondylolisthesis or lateral subluxation in degenerative scoliosis) or if it contributes significantly to the patient's axial back pain in the same setting. Utilizing the patient's own bone from the removed lamina or facet, fusion often involves titanium pedicle screws. Various methods, such as placing interbody cages in the intervertebral disc spaces after discectomy, may be used to enhance fusion and strengthen unstable spinal segments following decompression surgery.
The use of BMP (bone morphogenetic protein) is an advancement in surgical fusion, particularly in patients with higher risks of non-union, such as diabetics, smokers, and those undergoing multi-level and revision surgeries.
Current trends in spine surgery emphasise non-fusion surgery and minimally invasive techniques, particularly in the treatment of lumbar spinal stenosis in carefully selected patients. Non-fusion surgery utilises dynamic devices (e.g., interspinous spacers) after decompression laminectomy to limit spinal motion at the affected level. Minimally invasive surgery, facilitated by specially designed ports and screw systems, allows for reduced hospital stays and earlier return to work.