The Butterfly Test

Assess movement control of the cervical spine. Patient follows a moving target on screen using head movement.

Target moves at unpredictable velocity along Easy, Medium, and Hard trajectories. Trajectories are invisible to patient.

Facing monitor, 90 cm (35 inches) from center, monitor at eye level.

Select difficulty levels (Easy, Medium, Hard) and repetitions. Default: all levels, 1 rep each

This section describes the Butterfly Test, which evaluates cervical spine movement control by having the patient track an on-screen target with head movements under varying difficulty levels.