The immediate effects of torso weighting on balance and mobility measures of persons with Parkinson's disease

Background. The decline in postural control and functional mobility are related to negative health outcomes in people with Parkinson's disease (PD). Effective treatments that enhance balance and movement can improve quality of life in this population. The addition of small weights to the torso has been used to increase postural stability and functional performance in persons with movement dysfunctions. Its effectiveness has not been documented in persons with PD. The purpose of the study was to determine if small weights applied on the torso have immediate effects on balance and mobility in people with PD. Methods. This was a randomized, double-blind clinical trial. Forty-two subjects (18 female, 24 male) were randomly assigned to a no weight (NW), fixed weight (FW), and variable weight (VW) placement group. Outcome measures included the Modified Clinical Test of Sensory Interaction in Balance (mCTSIB), Tinetti Performance Oriented Mobility Assessment (POMA), Timed Up and Go (TUG), modified Timed Up and Go (mTUG), Functional Reach Test (FRT), 360° turns, ten meter walk and lower extremity strength. These measures were performed at baseline and after random group assignment. Analysis of Covariance (ANCOVA) was used to determine if statistically significant differences in the outcome measures existed across groups. Post hoc pairwise comparisons were performed as appropriate to identify the group that demonstrated the most significant improvement in a particular measure. Result. The VW group showed significant improvement in the ten meter walk compared with the NW group (p=.039) and the FW group (p=.008). The VW group also improved compared to the FW group on the following: Fast mTUG total (p=.024), Fast mTUG Split 3 (p=.006), right ankle plantarflexors (p=.019) and left knee extensors (p=.005). Without Bonferroni adjustments, the VW group also showed significant improvement in right ankle plantarflexors compared to NW (p=.030) and FW (p=.006) groups. Discussion. For torso weighting to be effective, the weights must be strategically placed in response to the directional balance loss. The findings support existing literature on the positive effects of torso weighting on balance and mobility in other neuromuscular conditions. More research is needed to determine the long term effects of this intervention.