What are radicular symptoms?

What Are Radicular Symptoms?

Radicular symptoms are pain or sensorimotor deficits caused by dysfunction of a spinal nerve root, typically presenting as sharp, shooting pain radiating in a narrow band down the extremity in the distribution of the affected nerve, often accompanied by sensory changes, motor weakness, or reflex abnormalities. 1

Clinical Presentation

Pain Characteristics

• Sharp, shooting, or lancinating quality that travels in a narrow band down the length of the affected extremity, both superficially and deep 2
• Pain follows a dermatomal distribution corresponding to the specific nerve root involved 1
• In cervical radiculopathy: neck pain radiating into one arm 1
• In lumbar radiculopathy: back pain radiating down the leg (sciatica) 1, 2

Associated Neurological Features

• Sensory deficits: numbness, tingling, or altered sensation in the affected nerve root distribution 1
• Motor deficits: weakness in specific muscle groups innervated by the affected nerve root 1
• Reflex abnormalities: diminished or absent deep tendon reflexes 1
• These objective findings constitute radiculopathy (conduction block), which may or may not accompany radicular pain 2

Pathophysiology

The mechanism involves more than simple mechanical compression 2, 3:

• Compression sensitizes the nerve root to mechanical stimulation 2
• Chemical-mediated inflammatory reaction occurs at the nerve root or dorsal root ganglion 2, 3
• Ectopic nerve impulses are generated and perceived as pain in the axonal distribution 3
• Prolonged repetitive firing (5-25 minutes) can occur with compression of the dorsal root ganglion or chronically injured nerve roots 3

Common Etiologies

Cervical Spine

• Disc herniation or bulging 1
• Foraminal stenosis from facet or uncovertebral joint hypertrophy 1
• Degenerative spondylosis 1

Lumbar Spine

• Disc herniation, most commonly at L4-L5 and L5-S1 levels 1
• Spinal stenosis 1
• Degenerative changes 1, 4

Epidemiology

• Cervical radiculopathy has an annual incidence of 83.2 per 100,000 people 1
• Lumbar radiculopathy is more common than cervical 4
• Most cases (>50%) resolve spontaneously with conservative treatment within 3-4 months 1, 2

Important Clinical Distinctions

Radicular Pain vs. Referred Pain

Radicular symptoms must be distinguished from somatic referred pain, which is diffuse, poorly localized, and does not follow dermatomal patterns 2. True radicular pain is narrow-banded and dermatomal 2.

Radicular Pain vs. Radiculopathy

• Radicular pain: subjective pain in nerve root distribution 2
• Radiculopathy: objective sensory and/or motor dysfunction from nerve conduction block 2
• These may coexist but are distinct entities 2

Clinical Pitfalls

Physical examination findings correlate poorly with imaging in cervical radiculopathy, with high rates of both false-positive and false-negative MRI findings 1. This is because:

• Disc abnormalities are common in asymptomatic individuals over age 30 1
• Spondylotic changes on imaging correlate poorly with symptoms 1

Progressive neurological deficits warrant urgent evaluation to exclude cauda equina syndrome (in lumbar spine) or myelopathy (in cervical spine), which require different management algorithms 1.