Discogenic Radiculopathy: Definition, Diagnosis, and Management

Definition and Pathophysiology

Discogenic radiculopathy occurs when a herniated disc or degenerative disc disease causes compression and/or irritation of a spinal nerve root, resulting in pain and neurological symptoms that follow the distribution of the affected nerve root 1, 2
The compression can be due to "soft disc" (herniated disc material) or "hard disc" (spondylarthrosis such as facet or uncovertebral joint hypertrophy) or a combination of both 1
Most commonly affects the cervical spine (particularly C5-C6 levels) and lumbar spine (particularly L4-L5 and L5-S1 levels) 1, 3

Presents with a combination of radiating pain along the affected nerve root distribution, sensory dysfunction, motor weakness, and associated neck or back pain at the site of nerve root compression 1, 2, 4

MRI without contrast is the preferred imaging modality for suspected discogenic radiculopathy due to its superior ability to visualize soft tissue abnormalities, including disc herniations and nerve root compression 1, 2
CT provides good definition of bony elements and can be helpful in assessing neuroforaminal stenosis due to uncovertebral or facet hypertrophy 2
Radiographs may be useful as initial screening but have limited value as degenerative changes are common in asymptomatic individuals and correlate poorly with symptoms 1, 2

Bilateral radiculopathy may indicate risk for cauda equina syndrome 6, 7
New changes in bladder function, subjective and/or objective loss of perineal sensation, and progressive neurological deficits require urgent evaluation 6, 7, 3

Surgical decompression should be considered when there is persistent or progressive neurological deficit despite conservative management 1, 4
Anterior cervical decompression is recommended for cervical radiculopathy when conservative management fails, with success rates of 52-99% reported 4

Recurrent symptoms have been reported in up to 30% of patients following surgical treatment 4

MRI findings alone should not be used to diagnose symptomatic radiculopathy due to high rates of both false-positive and false-negative findings 1
Always evaluate for red flags that might indicate more serious pathology requiring urgent intervention 6, 7, 3