Perspective: Balance Assessments in Progressive Supranuclear Palsy: Lessons Learned

Abstract

Many studies have examined aspects of balance in progressive supranuclear palsy (PSP), but guidance on the feasibility of standardized objective balance assessments and balance scales in PSP is lacking. Balance tests commonly used in Parkinson's disease often cannot be easily administered or translated to PSP. Here we briefly review methodology in prior studies of balance in PSP; then we focus on feasibility by presenting our experience with objective balance assessment in PSP-Richardson syndrome and PSP-parkinsonism during a crossover rTMS intervention trial. We highlight lessons learned, safety considerations, and future approaches for objective balance assessment in PSP.

Keywords: balance; gait; posturography; progressive supranuclear palsy; wearable sensors.

Figure 1

Our balance assessment in PSP protocol. SOT, Sensory Organization Test; C1, condition one (quiet stance without movement of the force plate or surround with eyes open); C2, condition two (quiet stance without movement of the force plate or surround with eyes closed); MCT, Motor Control Test; ABC, Activities-Specific Balance Confidence (ABC) Scale; FES-I, Falls Efficacy Scale-International.

Figure 2

Representative center of pressure sway excursions in quiet stance without movement of the force plate or surround (condition one of the Sensory Organization Test) before and after cerebellar repetitive TMS compared to sham TMS. rTMS, repetitive transcranial magnetic stimulation; CoP, center of pressure; AP, anterior-posterior; ML, medio-lateral; C1, condition one.