Reliability and validity of a scale for measurement of trunk mobility in Parkinson's disease: Trunk Mobility Scale.

Axial rigidity is an important motor manifestation in Parkinson's disease (PD). Trunk mobility impairment can cause gait, balance and postural problems. However, only few instruments analyze the trunk mobility in PD patients. The aim of this study is to present a new Trunk Mobility Scale (TMS) and its validation in PD. The TMS constituted of dynamic tests involving trunk movements in sagittal, transversal and coronal planes. Ninety eight PD patients and 31 normal controls were analyzed. A strong correlation was found between the TMS scores and the Hoehn & Yahr staging scale (r: 0.72; p<0.01), motor Unified Parkinson's Disease Rating Scale (r: 0.84; p<0.01) and Schwab and England Activities of Daily Living (r: -0.72; p<0.01). The scale showed a satisfactory reliability rate (αCronbach: 0.85, ICC: 099). TMS is a simple and reliable instrument to evaluate trunk mobility impairment in patients with PD.