title: A low-cost real time virtual system for postural stability assessment at home.
abstract: OBJECTIVE
  The degeneration of the balance control system in the elderly and in many pathologies requires measuring the equilibrium conditions very often. In clinical practice, equilibrium control is commonly evaluated by using a force platform (stabilometric platform) in a clinical environment. In this paper, we demonstrate how a simple movement analysis system, based on a 3D video camera and a 3D real time model reconstruction of the human body, can be used to collect information usually recorded by a physical stabilometric platform.
  
  
  METHODS
  The algorithm used to reconstruct the human body model as a set of spheres is described and discussed. Moreover, experimental measurements and comparisons with data collected by a physical stabilometric platform are also reported. The measurements were collected on a set of 6 healthy subjects to whom a change in equilibrium condition was stimulated by performing an equilibrium task.
  
  
  RESULTS
  The experimental results showed that more than 95% of data collected by the proposed method were not significantly different from those collected by the classic platform, thus confirming the usefulness of the proposed system.
  
  
  CONCLUSIONS
  The proposed virtual balance assessment system can be implemented at low cost (about 500$) and, for this reason, can be considered a home use medical device. On the contrary, astabilometric platform has a cost of about 10,000$ and requires periodical calibration. The proposed system does not require periodical calibration, as is necessary for stabilometric force platforms, and it is easy to use. In future, the proposed system with little integration can be used, besides being an emulator of a stabilometric platform, also to recognize and track, in real time, head, legs, arms and trunk, that is to collect information actually obtained by sophisticated optoelectronic systems.
authors: Department of Life, Health and Environmental Sciences, University of L'Aquila, Via Vetoio, 67100 L'Aquila, Italy. Electronic address: Giuseppe.placidi@univaq.it.
authors: Giuseppe
authors: G
authors: Placidi
authors: Department of Life, Health and Environmental Sciences, University of L'Aquila, Via Vetoio, 67100 L'Aquila, Italy.
authors: Danilo
authors: D
authors: Avola
authors: Department of Life, Health and Environmental Sciences, University of L'Aquila, Via Vetoio, 67100 L'Aquila, Italy.
authors: Marco
authors: M
authors: Ferrari
authors: Department of Computer, Control and Management Engineering Antonio Ruberti, Sapienza University of Rome, Via Ariosto 25, 00185 Rome, Italy.
authors: Daniela
authors: D
authors: Iacoviello
authors: Department of Life, Health and Environmental Sciences, University of L'Aquila, Via Vetoio, 67100 L'Aquila, Italy.
authors: Andrea
authors: A
authors: Petracca
authors: Department of Life, Health and Environmental Sciences, University of L'Aquila, Via Vetoio, 67100 L'Aquila, Italy.
authors: Valentina
authors: V
authors: Quaresima
authors: Department of Life, Health and Environmental Sciences, University of L'Aquila, Via Vetoio, 67100 L'Aquila, Italy.
authors: Matteo
authors: M
authors: Spezialetti
mesh_terms: D056044:Actigraphy / Q000295:instrumentation* / Q000379:methods; D000328:Adult; D003199:Computer Systems; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D008297:Male; D004856:Postural Balance / Q000502:physiology*; D015203:Reproducibility of Results; D012648:Self Care / Q000295:instrumentation* / Q000379:methods; D012680:Sensitivity and Specificity; D017216:Telemedicine / Q000295:instrumentation / Q000379:methods; D014584:User-Computer Interface; D014741:Video Recording / Q000295:instrumentation* / Q000379:methods; D051598:Whole Body Imaging / Q000295:instrumentation* / Q000379:methods
keywords: Body model representation; Home use medical device; Recognition and tracking algorithms; Stabilometric force platform; Virtual stability assessment