. 2022 Jun 8;23:550. doi: 10.1186/s12891-022-05485-5

Table 1.

Lumbar spinal stenosis clinical phenotype descriptions

LSS Phenotype	Symptom Description
TYPE A: NEUROGENIC CLAUDICATION PAIN SYMPTOMS	Neurogenic claudication describes the typical widespread lower extremity pain aggravated during walking in people with LSS. Symptoms of aching, cramping, pain or burning most commonly affect both legs, though not always symmetrically. The symptoms are precipitated by standing as well as walking and relieved with sitting/ forward flexion/ lying down. These dynamic, posture-related bilateral pain symptoms are generally considered to be associated with central canal stenosis in the lumbar spine
TYPE B: NEUROGENIC CLAUDICANT SENSORY/ BALANCE SYMPTOMS	Neuroischaemic symptoms associated with LSS include tingling, paraesthesia, numbness and weakness in the lower extremities, usually bilaterally, and can also include problems with balance. As with other LSS phenotypes, these neuroischaemic symptoms are precipitated by standing and walking. The symptoms are generally considered to be due to central canal stenosis in the lumbar spine causing intermittent compromise of the cauda equina/ nerve roots related to compression, venous stasis and hypoxia
TYPE C: RADICULAR UNILATERAL LEG PAIN SYMPTOMS	Radicular-type leg pain symptoms affecting predominantly one lower extremity are generally considered to be due to direct nerve root compromise associated with lateral recess canal stenosis or foraminal stenosis in the lumbar spine. These symptoms generally follow a specific dermatomal pattern. Symptoms are aggravated by standing and walking but may also be present at other times. Since there may be inflammation of the nerve root, symptoms are less influenced by change in posture, and can also be experienced at rest, when sitting or at night in bed

LSS Phenotype

Symptom Description

TYPE A:

NEUROGENIC CLAUDICATION PAIN SYMPTOMS

Neurogenic claudication describes the typical widespread lower extremity pain aggravated during walking in people with LSS. Symptoms of aching, cramping, pain or burning most commonly affect both legs, though not always symmetrically. The symptoms are precipitated by standing as well as walking and relieved with sitting/ forward flexion/ lying down. These dynamic, posture-related bilateral pain symptoms are generally considered to be associated with central canal stenosis in the lumbar spine

TYPE B:

NEUROGENIC CLAUDICANT SENSORY/ BALANCE SYMPTOMS

Neuroischaemic symptoms associated with LSS include tingling, paraesthesia, numbness and weakness in the lower extremities, usually bilaterally, and can also include problems with balance. As with other LSS phenotypes, these neuroischaemic symptoms are precipitated by standing and walking. The symptoms are generally considered to be due to central canal stenosis in the lumbar spine causing intermittent compromise of the cauda equina/ nerve roots related to compression, venous stasis and hypoxia

TYPE C:

RADICULAR UNILATERAL LEG PAIN SYMPTOMS

Radicular-type leg pain symptoms affecting predominantly one lower extremity are generally considered to be due to direct nerve root compromise associated with lateral recess canal stenosis or foraminal stenosis in the lumbar spine. These symptoms generally follow a specific dermatomal pattern. Symptoms are aggravated by standing and walking but may also be present at other times. Since there may be inflammation of the nerve root, symptoms are less influenced by change in posture, and can also be experienced at rest, when sitting or at night in bed

In clinical practice, patients often present with a combination of these three overlapping symptom descriptions. The phenotype descriptions were developed as an aid to survey participants rather than a reflection of real patients who often present with a mixture of symptoms, and were expected to prompt different treatment selections. Bilateral neurogenic claudicant pain symptoms described in phenotype A might be associated with bilateral foraminal or lateral recess stenosis as well as with central canal stenosis