Neural tension patterns during cervical spine rotation: diagnostic implications from a cadaveric study

Area of Science:

• Biomechanics
• Neuroscience
• Anatomy

Background:

• Cervical neural tension is crucial for spinal nerve function during positional changes.
• Current clinical tests inadequately assess upper and mid-cervical nerve tension, impacting diagnoses like occipital neuralgia.

Purpose of the Study:

• To quantify tensile load changes in upper and mid-cervical spinal nerves (C1-C5) during passive cervical spine rotation.
• To explore distinct tension patterns between upper and middle cervical segments.

Main Methods:

• Cadaveric study using five formalin-embalmed specimens.
• Measured tensile load on cervical spinal nerves (C1-C5) using force gauges.
• Assessed C1-C3 under flexion-rotation and C4-C5 under neutral-plane rotation.

Main Results:

• C1-C3 showed ipsilateral neural tension increases during flexion-rotation.
• C4-C5 demonstrated contralateral load increases during neutral-plane rotation.
• Significant variations in tensile load were noted at C5, with good-to-excellent reliability (ICC > 0.75) at C2-C5.

Conclusions:

• Cervical rotation significantly influences neural tension, with segment-specific patterns.
• Replacing lateral neck flexion with rotation in tension tests is a promising research direction.
• Findings support the flexion-rotation test for assessing greater occipital nerve tension and warrant further in vivo studies.