The effects of actual and simulated visual impairments on the walking gait: A systematic review

Background: Visual impairments (VI) affect over 2.2 billion people worldwide and are linked to an increased risk of falls. To date, no reviews have systematically synthesised evidence for the effect of VI on whole body gait biomechanics, to better understand how different types of VI might affect gait. Methods: A systematic search up to July 2025 was conducted using PubMed (MEDLINE), Scopus, Web of Science, and ERIC. Eligible studies included adults, a diagnosed or simulated VI, a non-visually impaired comparator, and reported any of the following gait parameters: 1) Spatio-temporal; 2) Kinetics; 3) Kinematics; and 4) Muscle activity. Study quality was evaluated using quality assessment with diverse studies (QuADS) and a narrative synthesis undertaken (SWiM). Findings: Forty-four studies were included. Twenty-seven examined straight-line level walking, 12 examined obstacle walking and five examined both straight-line level and obstacle walking. Of those examining straight-line level walking, 12 simulated VI and 15 explored diagnosed VI's. In the obstacle walking literature, nine simulated VI and six included participants with diagnosed VI's. Inconsistent findings were common across studies, with most reporting either a more cautious gait strategy with VI, or no difference between VI and non-VI conditions. Interpretation: Differences between studies are likely explained by variation in gait measurement, non-standard VI simulation methods, and lack of detail surrounding the severity of diagnosis. This hinders provision of clinical recommendations based on existing evidence. We have proposed minimum reporting requirements around acuity, contrast sensitivity, visual field method/thresholds; simulation validation to facilitate clinical utilisation.