C4/C5 Disc Extrusion with Spinal Cord Edema Presentation

Understanding the Anatomical Mismatch

Spinal cord edema at C4/C5 typically manifests with bilateral hand weakness, gait disturbance, hyperreflexia, and sensory changes below the level of compression, according to the World of Neurosurgery 1, 2, 3.
The American College of Radiology notes that C4/C5 level cord compression presents with bilateral hand numbness and weakness, burning dysesthesias in forearms, and involvement of multiple muscle groups including biceps, triceps, wrist extensors, and finger flexors bilaterally 1, 2, 4.
Patients with cervical spinal cord injury at this level characteristically show hand dysfunction affecting both fine motor control and grip strength, often with lower extremity involvement, as reported by the World of Neurosurgery 5, 3.

Bilateral hand clumsiness and weakness, not just finger drop, are expected in patients with C4/C5 disc extrusion causing spinal cord edema, according to the World of Neurosurgery 1, 4.
Gait disturbance or lower extremity weakness are common findings in patients with spinal cord edema at C4/C5, as noted by the World of Neurosurgery 1.
Sensory level or patchy sensory changes are also expected in patients with C4/C5 disc extrusion causing spinal cord edema, according to the World of Neurosurgery 1, 4.

C6 or C7 radiculopathy from a different level, such as C5/C6 or C6/C7 disc herniation, can cause isolated finger drop, as reported by the Journal of the American College of Radiology 6, 7.
Posterior interosseous nerve compression, a radial nerve branch, can also cause finger drop, according to the Journal of the American College of Radiology 6.
Peripheral nerve pathology unrelated to the cervical spine can also cause isolated finger drop, as noted by the Journal of the American College of Radiology 7.

A comprehensive neurological examination should include testing all upper extremity myotomes systematically, assessing reflexes, evaluating gait and lower extremity strength and reflexes, and testing sensory function in dermatomal distribution and for sensory level, as recommended by the World of Neurosurgery 1.
The American College of Radiology notes that MRI findings of cord edema at C4/C5 should correlate with clinical myelopathy, and that correlation with clinical examination is essential to avoid false-positive findings in asymptomatic individuals 6, 7.