The link between lateral trunk flexion in Parkinson’s disease and vestibular dysfunction: a clinical study

Abstract

Introduction

Lateral trunk flexion (LTF) is a common postural deformity in Parkinson’s disease (PD). Postural control is known to depend on visual, vestibular, and somatosensory information.

Objectives

This study aimed to investigate the relationship between vestibular dysfunction and postural abnormalities in PD patients with LTF.

Methods

We enrolled a total of 19 PD patients with LTF (PD-LTF+) and 19 age- and sex-matched PD patients without LTF (PD-LTF-). All patients underwent vestibular tests, including spontaneous nystagmus, gaze-evoked nystagmus, ocular movements, optokinetic eye test, fast positioning maneuvers, and the bithermal caloric test.

Results

Most of the PD-LTF + patients had abnormal vestibular function (11/19), while there were fewer vestibular function injuries in the control group (3/19). In PD-LTF + group, there were 5 patients (5/11, 45.5%) of peripheral vestibular dysfunction, 2 patients (2/11, 18.2%) of central vestibular damage, and 4 patients (4/11, 36.4%) of mixed injuries. The peripheral vestibular deficiencies could be either bilateral (4/9, 44.4%) or unilateral (5/9, 55.6%). The unilateral vestibular dysfunction was ipsilateral to the leaning side in 2 patients and contralateral to the leaning side in the other 3 patients.

Conclusion

Vestibular dysfunction may be an independent risk factor for LTF in PD patients.

Keywords:

• Parkinson’s disease
• lateral trunk flexion
• Pisa syndrome
• vestibular dysfunction
• nystagmus

Acknowledgements

We thank the patients for participating in this study.

Author contributions

HYT and WL contributed to study concept and design; HYT contributed to drafting of the manuscript; YC, ZDC and WL contributed to critical revision of the manuscript for important intellectual content; DNL, YT and ZYOY contributed to enrolling patients.

Disclosure statement

No potential conflict of interest was reported by the author(s).