Subjective postural vertical in Parkinson's disease with lateral trunk flexion

BACKGROUND Patients with Parkinson's disease (PD) and associated lateral trunk flexion (LTF) cannot accurately perceive their own verticality. OBJECTIVE We measured the subjective postural vertical in coronal plane (SPVc) angle on patients' ipsilateral and contralateral sides and combined to clarify the effects of SPVc on LTF. We also investigated effects of the SPVc angle on LTF severity. METHODS Thirty-nine patients (aged 74.1 ± 7.6 years) were divided between those with mild LTF (LTF angle