What is the primary cause of lumbar radiculopathy?

• A. Degenerative spondyloarthropathies
• B. Traumatic fracture
• C. Infectious arthritis
• D. Congenital stenosis

Answer: (A)

Lumbar radiculopathy happens when a lumbar nerve root is compressed or irritated as it exits the spinal canal. The most common source of this compression in adults is degenerative changes in the spine—spondyloarthropathies such as facet joint arthritis and osteophyte formation—that narrow the intervertebral foramina or the canal itself. This degenerative narrowing reduces space for the nerve root, leading to dermatomal leg pain, numbness, and sometimes weakness.

Traumatic fractures can injure nerves but are a less frequent cause of radiculopathy compared to chronic degenerative changes. Infectious arthritis is unlikely to be the primary driver, and congenital stenosis can cause symptoms but is less common overall in adults with radicular pain. So, degenerative spondyloarthropathies are the most likely primary cause among these options.