Arm-trunk coordination as a measure of vestibulospinal efficiency

作者：Sibindi Tafadzwa M; Krasovsky Tal; Feldman Anatol G; Dannenbaum Elizabeth; Zeitouni Anthony; Levin Mindy F^*

来源：Journal of Vestibular Research-Equilibrium & Orientation, 2013, 23(4-5): 237-247.

DOI：10.3233/VES-130485

• Motor control
• vestibular deficiency
• rehabilitation
• arm-trunk coordination
• measurement

When arm and trunk segments are involved in reaching for objects within arm's reach, vestibulospinal pathways compensate for trunk motion influence on arm movement. This compensatory arm-trunk synergy is characterised by a gain coefficient of 0 to 1. Vestibular patients have less efficient arm-trunk synergies and lower gains. To assess the clinical usefulness of the gain measure, we used a portable ultrasound-based device to characterize arm-trunk coordination deficits in vestibular patients. Arm-trunk coordination without vision was measured in a Stationary Hand Task where hand position was maintained during trunk movement, and a Reaching Task with and without trunk motion. Twenty unilateral vestibular patients and 16 controls participated. For the Stationary Hand task, patient gains ranged from g = 0.94 (good compensation) to 0.31 (poor compensation) and, on average, were lower than in controls (patients: 0.67 +/- 0.19; controls: 0.85 +/- 0.07; p < 0.01). Gains were significantly correlated with clinical tests (Sensory Organization; r = 0.62, p < 0.01, Foam Romberg Eyes Closed; r = 0.65, p < 0.01). For the Reaching Task, blocking trunk movement during reaching modified hand position significantly more in patients (8.2 +/- 4.3 cm) compared to controls (4.5 +/- 1.7 cm, p < 0.02) and the amount of hand position deviation was correlated with the degree of vestibular loss in a sub-group (n = 14) of patients. Measurement of the Stationary Task arm-trunk gain and hand deviations during the Reaching Task can help characterize sensorimotor problems in vestibular-deficient patients and track recovery following therapeutic interventions. The ultrasound-based portable device is suitable for measuring vestibulospinal deficits in arm-trunk coordination in a clinical setting.

• 出版日期2013