Abstract
Purpose :
Due to reduced visual information, dynamic balance can be impaired in patients with peripheral field loss (PFL). Sensitive and reliable balance measures are needed to support the development and testing of new postural and mobility interventions. We examined the reliability of two new dynamic measures of balance in PFL patients and age-matched healthy controls (HC).
Methods :
Fifteen patients with PFL (65.47±3.96 years) and 15 HC subjects (64.1±3.24 years) completed three tests. Timed up and Go (TUG) test involved standing up from a chair, walking 3m, turning around, walking back to the chair, and sitting down. Narrow path walking test (NPWT) was adopted from the TUG test. A green rubber mat (40 x 300 cm, Michelson contrast of 24%) divided the path into two 20-cm wide pathways. Participants completed the TUG test procedure using this narrow path. Landing balance test (LBT) involved stepping onto a force plate located 60 cm away and standing still. A vicon motion system was used to measure dynamic balance. For TUG and NPWT, spatial-temporal gait parameters were analyzed. For LBT, time to stabilize and sway area were analyzed. Each testing condition was repeated 6 times, and the tests were repeated within 2 weeks to examine the test-retest repeatability.
Results :
Performance on the NPWT and LBT was significantly worse for the PFL group than HC (p<0.05). The PFL group was slower on the NPWT (16.61 vs 13.74s), possibly due to slower walking speed, smaller cadence, wider base of support and shorter step length. For the LBT, the PFL group had a larger sway area (1834.1 vs 1260.94mm2, p<0.05). Intraclass correlation coefficients (ICC) for the parameters in NPWT and LBT ranged from 0.83 to 0.99 between two visits. Good limits of agreements of completion time and time-to-stabilize were shown in the Bland and Altman test for NPWT and LBT respectively.
Conclusions :
Both NPWT and LBT were sensitive and reliable measures for assessing dynamic balance for PFL and HCs in this study. Compared with the HC group, the PFL group had worse gait performance under challenging conditions.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.