Attenuation of trunk acceleration during walking in patients with unilateral vestibular deficiencies

Head stability, central for balance control during locomotion, is associated with attenuation of trunk oscillations. The study aimed at exploring trunk attenuation in patients with unilateral vestibular disorder (UVD) assuming it was compromised, and to see if attenuation could be influenced by vestibular rehabilitation therapy.

Patients with UVD (N= 21), mean age (SD): 50.7 (11.5) years, women: 57%, were tested before and after intervention. Patients walked at different velocities with triaxial accelerometers over the lower and upper trunk. Normalization of data allowed comparison across patients over time. Self-reported symptoms and perception of handicap were registered.

Acceleration was significantly higher at the lower compared to the upper trunk on both occasions. Increased accelerations at the lower and decreased accelerations at the upper trunk following intervention caused attenuation to increase along the antero-posterior (p=0.05) and medio-lateral axes (p< 0.01). Cadence was reduced (p=0.01), step-length increased (p= 0.01), and self-reported balance (p=0.05) and handicap (p<0.01) improved.

More effective attenuation of trunk oscillations was found during walking following intervention. The observed increased stability of the upper trunk is compatible with improved head control, and this was associated with increased mobility of the lower trunk facilitating balance control during ambulation. Trunk accelerations may be useful for identification of balance control in UVD patients.