Quantitative analysis of sit to stand movement: experimental set-up definition and application to healthy and hemiplegic adults

Rising from a chair or sit to stand (STS) is a movement with a great clinical interest: it is meaningful in order to evaluate motor control and stability in patients with functional limitations. STS requires some skills, as coordination between trunk and lower limbs movements, correction of muscles strength, control of equilibrium and stability and it is often considered into clinical evaluation scales of different pathologies. In literature, although some studies are focused on STS, the essential functions of standing up are not well standardized and uniformly defined: for this reason its application in clinical centres is difficult. In this study an experimental set-up for acquisition of STS movement which is suitable for clinical applications has been proposed: first, it was studied in healthy subjects, to define a normative database of this specific motor task, then in pathological subjects (adults with hemiplegia), to quantify their functional limitation, using quantitative kinematic and kinetic parameters. The results showed that this experimental set-up is effective both in healthy and in pathological subjects; some significant parameters were identified and calculated in order to characterise and quantify the functional limitation of patients.