Identifying Asymmetries in Reaction Time and Reach Distance by Adding a Neurocognitive Component to the Y-Balance Test of the Lower Quarter

The study team will measure performance under two conditions: the standard Y-Balance Test (YBT) and the YBT with an added neurocognitive component (YBT+NC). For the YBT+NC, the study team will attach Blaze Pods to the target area of the three reach indictors: anterior (A), posteromedial (PM), and posterolateral (PL). The Blaze Pods will light up in random sequences, requiring participants to slide the illuminated reach indicator as far as possible while maintaining balance on the stationary stance limb. Reaction time, individual reach distances (PM,PL,A), YBT composite score, and number of errors will be recorded and compared bilaterally.

To first establish feasibility and clinical utility, a pilot group of healthy participants will perform both the YBT and the YBT+NC with two simultaneous testers on two separate occasions separated by at least one day but no more than 28 days. The differences in reach distances, composite scores, and reaction times between the two test conditions will be compared. The study team will also determine intra- and inter-rater reliability as well as any learning effects.

For the patient cohort, the study team will employ a cross-sectional design to measure patients presenting for physical performance testing battery between 5-8 months post-anterior cruciate ligament reconstruction/repair (ACLR). This visit is standard of care for this population. If the patient is able to pass the initial screening test (maintain pain-free single leg balance for 10 seconds) a physical therapist will have the patient perform both the YBT and the YBT+NC as described above. The study team will compare the side-to-side differences between reaction time, reach distance, and number of errors (loss of balance) made.