Patients with central visual field loss adopt a cautious gait strategy during tasks that present a high risk of falling.

PURPOSE: To investigate how patients with central visual field loss (CFL) complete adaptive gait tasks when compared to visual normals and determine whether task difficulty significantly affects movement control.

METHODS

Ten patients with CFL and 12 visual normals negotiated a floor-based obstacle (of different heights, 5 and 10 cm) and also walked across an unobstructed laboratory (no obstacle present). Analysis assessed the kinematics of human movement for each task.

RESULTS

During obstacle crossing, compared to visual normals, patients with CFL lifted their lead and trail foot significantly higher to avoid the obstacle, reduced horizontal crossing velocity (only significant at low obstacle height), and increased head flexion to look down at more immediate areas of the ground (P < 0.05). During the walking only trials there was no significant difference between the two groups in any of the kinematic measures. CONCLUSIONS; Compared to visual normals, patients with CFL adopt a cautious gait strategy during tasks that present a high risk of falling, such as obstacle crossing. However, under conditions that present a low risk of tripping or falling, such as level walking, differences appear minimal.