Effects of neurocognitive reactive activities on upper extremity closed kinetic chain functional performance testing

Existing UE return-to-sport (RTS) decision-making criteria do not assess neurocognitive (NC) deficits, increasing the risk of reinjury. This study aimed to establish the test-retest reliability of two NC reactive (NCR) variations of an upper extremity (UE) functional performance test (FPT).

Forty-two healthy adults completed two trials each of the Closed Kinetic Chain (CKC) UE Stability Test and two NCR variations, the UE Reactive CKC Test-Single Light (UERCKCT-SL) and UE Reactive CKC Test-Multi-Light (UERCKCT-ML), on two separate days. The average number of touches and reaction time were recorded. Reliability was assessed using systematic bias, total error, intraclass correlation coefficients (ICC), and 90% minimal detectable change.

ICC results for each test ranged from .669 to .816 for females and .676 to .872 for males. A significant difference in the average number of touches performed between the test variations was observed for both females (F _2,38 = 7.6, p = .002, ${\eta }_p^2$  = .29) and males (F _2,42 = 13.5, p < .001, ${\eta }_p^2$  = .39). Test reaction time differences between the UERCKCT-SL and UERCKCT-ML were not significant for females (t ₁₉ = 1.20, d = 0.21, P = .245, CI_diff = -56.78 to 15.43) and males (t ₂₁ = 0.40, d = 0.05, p = .692, CI_diff = -59.65 to 40.33).

Adding NCR multitask UE testing may improve RTS decision-making guidelines by better mimicking sporting demands. However, further research is needed to identify clinically suitable and ecologically valid NCR UE CKC FPT.