Mobile assessment of visual function helps to prevent Re-Injury in elderly patients with recent hip fractures

Patients undergoing surgery due to hip fracture face an elevated risk of a subsequent fall during rehabilitation. An important contributing factor to this risk is deteriorated visual function, often responsive to intervention. This study aims to explore differences in visual acuity (VA) and stereovision (SV) between individuals with a history of fall-related hip injuries (study group) and age-matched controls, utilizing a mobile application (EuvisionTab, ET) to distinguish age-related visual decline from pathological vision.

A total of 32 and 71 participants were enrolled in the study and control groups, respectively (mean age: 74.9 years, range: 60-96). Monocular logMAR VA was measured using a tablet by means of an adaptive threshold-search algorithm. SV was assessed using low-dot density static and dynamic random dot stereograms. An age-dependent reference limit for VA was established. For ET stereotests, the number of correctly identified optotypes out of 10 random presentations served as the measure for further comparisons. Visually impaired status in the study group was determined if patients failed either the VA threshold or the SV criteria.

In the control group, an apparent but statistically nonsignificant decline in VA was observed, while stereovision remained stable and did not exhibit significant age-related variations based on ET stereotests. Conversely, the study group demonstrated significantly worse results in monocular VA (p = 0.0032) and for both stereotests (p = 0.018 for static, p = 0.036 for dynamic) according to paired samples t-test and chi-square test, respectively. Hip injuries were significantly associated with visual impairment (OR = 4.88, p = 0.0012).

This study focuses on one possible risk factor of elderly falls, namely, vision impairment. Patients with visual decay present a higher incidence of hip injuries compared to age-matched controls. This data suggest that vision screening and, when feasible, restoration of visual function may contribute to the prevention of secondary falls, refractures, or contralateral fractures. A mobile-based screening protocol, executable as part of a postoperative bedside examination and independent of specialized eye care, can be proposed.