The effects of external support methods on elbow proprioception

Background: This study aimed to compare the acute effects of external support approaches (counterforce, sleeve, and sham brace) on elbow proprioception in asymptomatic individuals. Methods: The study included 20 individuals in the counterforce brace group (age: 23.00/6.50 years), 20 in the sleeve brace group (22.50/2.70 years), and 20 in the sham brace group (22.5/5.75 years). Proprioception assessment was conducted using the active joint position sense error (JPE) with a universal goniometer (Miyang, China). Target angles were set at 70° and 110° of elbow flexion. Evaluations were performed at 3 time points: Baseline (BS), immediately after wearing orthosis (IA), and 30 minutes after wearing orthosis (30MA). ANOVA-type statistics were applied for group, time, and group*time interactions. Between-group comparisons were utilized with the Kruskal-Wallis test, while within-group comparisons were employed with the Friedman Analysis. Results: At 70°, JPE scores were similar in terms of time points and groups (respectively p=0.055; p=0.095). No statistically significant difference was observed regarding group time point interaction (p=0.476). At 110°, statistically significant differences were observed in JPE scores regarding time points and groups (respectively p=0.020; p=0.005). No statistically significant difference was noted for the group time point interaction at 110° (p=0.346). At 70°, in the sleeve group, significant differences were identified between BS-30MA (p=0.001) and IA-30MA (p=0.009). At 110°, in the sleeve group, significant differences were observed between BS-30MA (p=0.007) and IA-30MA (p=0.007). In the counterforce group, significant differences were identified between BS-30MA (p=0.001). In the counterforce group at 70°, no difference was found between time points (p>0.05), while at 110°, a significant difference was observed (p<0.05). In the sleeve and sham groups, no differences were identified between different time points at 70° and 110° (p>0.05). Conclusion: In asymptomatic individuals, sleeve orthosis enhanced elbow proprioception at 70°, while counterforce and sleeve orthoses were effective at 110°. A 30-minute duration of orthosis use may be insufficient to achieve adequate statistical power. Studies involving different usage durations could more effectively elucidate the effects of orthoses on proprioception. These orthoses can be utilized in asymptomatic individuals without suppressing elbow proprioception.