Postural Control Determinants of Gait Dysfunction in Huntington's Disease.

BACKGROUND

Gait dysfunction is an important concern in Huntington's disease (HD). The influence of HD-specific postural control impairments on gait dysfunction, from pre-manifest HD (pHD) to manifest HD (mHD), is poorly understood.

OBJECTIVES

To explore the interplay of posture and gait in HD, we first (Aim 1) quantified the extent of deficits in postural control and gait across the spectrum of HD. Subsequently (Aim 2), we examined the contributions of postural control impairments to gait dysfunction.

METHODS

Participants (N = 38) included healthy controls (n = 10), pHD (n = 17), and mHD (n = 11). We quantified postural control using wearable sensors during sensory-challenging conditions using Jerk and Total Sway Area, and gait at self-selected pace, using outcomes of gait quality (peak swing velocity, stride length, cadence, %stance, and %swing) and stride-to-stride variability. We examined between-group differences (Aim 1) and conducted multiple regression analyses (Aim 2).

RESULTS

Impairments in postural control (Jerk and Total Sway Area) and gait (primarily variability) were evident in pHD and substantially increased in mHD (P < .05). Postural control deficits explained 14% to 39% of variance of gait dysfunction based on quality and variability, and gait items of the Unified Huntington's Disease Rating Scale (P < .05).

CONCLUSIONS

Deficits in postural control and gait begin in the pre-manifest stage, and worsen in manifest HD, highlighting the need for earlier intervention. Our results highlight that postural control deficits contribute substantially to gait deficits in HD, rather than merely co-occurring. Further investigation is required to understand how posture-gait link can be applied to clinical gait rehabilitation programs.