Pseudoradicular syndromes

Radicular and pseudoradicular lower back pain are different types of pain that radiate distally at the legs. Radicular pain radiates below the knee and is thought to stem from disorders associated with nerve root compression which is often felt in distal dermatomes below the knee (projected pain). In contrast, pseudoradicular pain does not radiate below the knee and is thought to be associated with local proximal disorders that do not affect any nerves or nerve roots.

The distinction between radicular and pseudoradicular lower back pain is clinically relevant for several reasons:
(i) radicular pain has always a neuropathic component because it always involves damage or irritation of peripheral nerves or nerve roots. In contrast, pseudoradicular pain may occur without damage or irritation of peripheral nerves or nerve roots and, thus, might be purely nociceptive. This distinction is very important when evaluating the results of neurophysiologic examinations.
(ii) Radicular pain (neuropathic pain) is predominantly sensitive to antidepressants and anticonvulsants. In contrast, pseudoradicular pain (nociceptive pain) is predominantly sensitive to nonsteroidal anti-inflammatory drugs (NSAIDS).

Diagnosis is based on the clinical features. Diagnostic imaging should be considered to rule out other causes of lower back pain or to establish the diagnosis of radicular or pseudoradicular lower back pain when in doubt. However, it should be noted that abnormalities found in radiological examinations in the lumbar spine poorly correlate with clinical symptoms.

Radial shock wave therapy (RSWT) is a very effective alternative to conservative treatment in pseudoradicular lower back pain.