Diagnostics Cervical Spine Dominant Eye

Instruct the person to sit comfortably, with feet on the floor and hands relaxed on the lap. Place a lit candle or any other light source 1 to 2 meters away from the person. Have the person gaze at the light source with both eyes open. Provide a sheet of paper with a small hole and ask the person to maintain both eyes open while looking at the light source through the hole, held at arm's length.

Once the person sees the light source through the hole, cover one eye and inquire whether they can still see the light source. Repeat the process with the other eye. The ability to see the light source through the hole in the sheet indicates the unconscious choice of the dominant eye. If the person sees the light source with the right eye, it is identified as the dominant eye. When looking at something with the dominant eye, the other eye adjusts accordingly.

The dominant eye test serves as a diagnostic tool to determine the preference for lateral flexion of C0-C1. The dominant eye influences the preferred lateral flexion of C0-C1, directing it to the homolateral side. This lateral flexion of C0 on C1 moves the facies articularis of C0 to the median line, causing compression and establishing a punctum fixum—a rotational axis for subsequent rotation and either extension or flexion.

The compression on C1 extends further down to C2, putting C2 in the same lateral flexion.

The direct connection between C2 and C0, the ligamentae alare, stretches on the contralateral side and relaxes on the homolateral side. Due to the biconcave joints between C1 and C2, which induce opposite rotation, and the consistent lateral flexion, it can be concluded that, alongside the opposite rotation, there is also an opposite direction in the transverse plane (flexion or extension).