Lumbar spinal stenosis (LSS)

  • is a degenerative condition where there is reduced space for nerve and vascular elements in the lumbar spine because of degenerative changes in the spinal canal.
  • May cause a pain that spreads outwards and tingling in the backside, thighs or legs, especially during walking or standing for a long time. The pain usually gets better when the patient is at rest, is sitting down or bends forward.
  • It is linked to ageing and mainly affects people over 60.

Not all patients with spinal column contraction develop symptoms, so the term ‘spinal stenosis’ relates to symptoms of pain, not the contraction itself and diagnosis is made only once symptoms are present.

Some people are born with a small spinal canal. This is called ‘congenital stenosis’. Contraction of the spinal canal is most often due, however, to changes related to age which come on over time. This is called ‘acquired spinal stenosis’. Spinal stenosis is most common in people over 50.

Acquired forms of LSS are also classified as degenerative, spondyolytic, iatrogenic (post-surgical), post-traumatic or combined.

Lumbar spinal stenosis may be caused by:

  • Degenerative spondylitis – when a person ages, changes in deterioration caused by trauma, along with other factors, intervertebral discs may degenerate and protrude on the rear side, causing greater strain on the rear elements of the vertebrae. This may lead to the formation of osteophytes at the rear of the spinal column, hypertrophy of the facet joints, synovial facet cysts and hypertrophy of the ligamentum flavum, which in turn leads to spinal stenosis.
  • Degenerative spondylolisthesis – when degenerative changes occur on the spinal column, the pars interarticularis may be broken and the resulting instability may lead to displacement of the vertebrae to the front. Enough frontal sliding of one vertebrae onto the next vertebral segment (usually L4-on-L5) may cause a contraction of the spinal canal, leading to stenosis.
  • Other acquired conditions, although rarer than the abovementioned ones, include space-occupying lesions, post-operative fibrosis and rheumatological conditions, as well as other skeletal conditions such as ankylosing spondylitis or diffuse idiopathic skeletal hyperostosis or are secondary vis-à-vis congenital causes such as skeletal conditions – which may lead to short handles with medial facets.
    • Osteoarthritis
    • Inflammatory spondyloarthropathy
    • Disc protrusion
    • Swelling of back ligaments
    • Tumour
    • Infection
    • Various metabolic bone diseases which make the bones grow, such as Paget’s disease.

Usually, lumbar spinal stenosis manifests as pain which gets worse with prolonged movement, when standing up and with a lumbar extension and is relieved by bending forwards and resting. Neurogenic claudication is a distinctive feature of lumbar spinal stenosis. Patients complain of pain or discomfort spreading out over the backside, thigh and lower leg after walking a certain distance, which leads to functional disability and reduces patients’ ability to walk.

Symptoms are usually bilateral but asymmetrical.

Most patients report pain in the lower back, tingling and numbness.

Tingling and numbness during lumbar spinal stenosis usually comprises the whole leg and rarely includes just one distribution of the nerve root .

Around 43% of patients feel weakness.

Patients may also report that they find it easier to walk upstairs rather than go downstairs as when walking up they back is inclined forward.