Lumbar Spinal Stenosis

Procedure

Patient standing. Ask the patient to lean back into lumbar extension and hold for 30 seconds, with support if balance is poor. Note any symptoms in the buttocks or legs and how quickly they ease afterwards.

Positive Finding

Reproduction of the familiar buttock, thigh or leg pain, heaviness or tingling during sustained extension, easing once the patient returns to upright or bends forward.

Interpretation

Extension narrows the spinal canal and the foramina, so leg symptoms brought on by sustained extension fit neurogenic claudication from stenosis. Combine it with the history: older age, leg symptoms on standing and walking, and relief with sitting or bending forward. Imaging is needed to confirm stenosis if it would change management. A JAMA review of the clinical examination for lumbar spinal stenosis (Suri 2010; 4 studies, 741 patients) gives no accuracy figure for the extension test. In one of its studies (Katz 1995; 93 patients), thigh pain after 30 seconds of lumbar extension was one of four findings independently linked to the diagnosis. In these studies the reference was an expert's diagnosis confirmed on imaging, and that diagnosis was partly based on the same history and examination, so the figures are shown here as a note and not as test accuracy.

Procedure

When the patient's leg symptoms are present (for example after standing or walking), ask them to sit down or bend forward, such as leaning on a trolley, and note how quickly the symptoms change.

Positive Finding

The leg pain, heaviness or tingling eases within a few minutes of sitting or bending forward.

Interpretation

Flexion widens the spinal canal, so relief with sitting or bending forward is typical of neurogenic claudication from stenosis. Leg pain from poor circulation eases with standing still and does not need a change in posture, which helps tell the two apart. Check the foot pulses in anyone with walking-related leg pain. A JAMA review of the clinical examination for lumbar spinal stenosis (Suri 2010; 4 studies, 741 patients) found that symptoms improving when bending forward were reported by 52% of people with stenosis and 8% of those without (Konno 2007; 469 patients), and symptoms improving when sitting by 51% and 16% (Katz 1995; 93 patients). Both findings make stenosis more likely. In these studies the reference was an expert's diagnosis confirmed on imaging, and that diagnosis was partly based on the same history and examination, so the figures are shown here as a note and not as test accuracy.

Procedure

Ask the patient to walk at a comfortable pace, on level ground or a treadmill, and record the time or distance until leg symptoms begin and until they force a stop. Note what relieves them (standing still, sitting, bending forward). A treadmill test can be repeated with an incline, which puts the spine into flexion.

Positive Finding

Leg symptoms that come on with walking and ease with sitting or bending forward. Walking uphill or leaning on a trolley often lets the patient walk further.

Interpretation

A pattern that fits neurogenic claudication from stenosis; walking distance is also a useful outcome measure over time. Symptoms that ease simply by standing still, with weak or absent foot pulses, suggest vascular claudication and need medical referral. In a small study (Fritz 1997; 45 people, 26 with stenosis), a two-stage treadmill test (walking on the level, then on an incline) helped separate the groups: earlier onset of symptoms on the level and a longer recovery afterwards both pointed to stenosis. Combining the treadmill measures correctly classified 77% of people with stenosis and 95% of those without. The study was small, so no single figure is shown.

Procedure

Patient supine. Lift each leg in turn with the knee straight until symptoms appear, noting the angle and where the symptoms are felt.

Positive Finding

Reproduction of the familiar radiating leg pain, usually below the knee.

Interpretation

The SLR is usually negative in central canal stenosis, because the symptoms depend on posture and walking rather than nerve tension. A positive SLR suggests nerve-root irritation, for example from a disc herniation or narrowing in the lateral recess, and should lead to a full neurological examination. The SLR tests nerve-root tension, mainly from disc herniation (see that page). Its published accuracy is for disc herniation, not spinal stenosis, so no figure is shown here.

Procedure

Patient lies with the trunk prone on the plinth and the feet resting on the floor. Apply posterior-to-anterior pressure to each lumbar level and note any pain. Then ask the patient to lift the feet slightly off the floor (activating the back extensors) and repeat the pressure at the painful level.

Positive Finding

Pain with pressure when the feet are on the floor that eases or disappears when the feet are lifted.

Interpretation

Developed to help identify people with low back pain who may respond to stabilising exercise; it is not a test for spinal stenosis. A positive result suggests muscle activation reduces the pain, which can guide exercise choice. This entry previously described a different procedure. The prone instability test is not a test for spinal stenosis, and the figure stored here had no source for this use. No figure is shown.

Procedure

Patient standing. Apply gentle downward pressure through both shoulders for a few seconds and ask about any change in back or leg symptoms.

Positive Finding

Increase in the familiar back or leg symptoms with downward pressure.

Interpretation

Not a standardised or recognised diagnostic test for stenosis. In some frameworks, back pain reported with very light pressure through the head or shoulders is treated as a non-organic (Waddell) sign that should prompt a look at psychosocial factors. Interpret any response with caution. A JAMA review of the clinical examination for lumbar spinal stenosis (Suri 2010; 4 studies, 741 patients) found no study of this test.