Clinical features
The presentation is typically insidious.
- usually presents in the sixth or seventh decade
- a long history of low back pain may be present but patients usually presents with leg symptoms
Pain is often the main complaint.
- commonly seen in the lower back, buttocks, thighs, and legs
- patients may describe the discomfort as a cramping or burning feeling
- pain may vary from a gradual onset of dull aching pain in the sacroiliac area and posterolateral thighs to sharp radicular pain in the thighs, legs, and feet
- bilateral (but not entirely symmetrical) pain may be seen in central canal LSS while in exclusively foraminal or lateral recess stenosis, patients may report symptoms resembling unilateral radiculopathy.
In addition patients may have the following symptoms:
- problems with balance
- sensory loss - numbness or tingling
- lower extremity muscle weakness
Neurogenic claudication is the cardinal symptom present in patients with central LSS
- it is the most specific symptom for the central LSS
- there is progressive onset of pain numbness, weakness and tingling in low back, buttocks and legs
- usually occurs with changes in posture (e.g. - by standing, or lumbar extension) and increased by walking. Sitting or forward flexion reduces the symptom
- flexed or stooped position of the patient when walking ("shopping cart sign") is an indication of neurogenic claudication.
- this or the inability to stand fully upright may be the presenting symptom in some cases
- it is important to differentiate claudication caused by LSS from vascular claudication related to peripheral vascular disease
Symptoms of LSS usually have a significant impact on patients' day to day life. Many will have problems with walking and may require walking aids or in some instances may even avoid walking altogether.
Note:
- low back pain in the absence of leg symptoms is usually not thought to be caused by LSS even in the presence of severe anatomic stenosis (may be controversial in some cases)
Reference:
- Lurie J, Tomkins-Lane C. Management of lumbar spinal stenosis. BMJ.2016;352:h6234.