Shape tracing app for movement disorder detection

Shape tracing tests for the detection and assessment of hand movement disorders are predominantly performed manually in the presence of a clinician. These procedures are therefore labour intensive, expensive, and subjective. Digital tests have been proposed to automate this assessment process, to answer the need of affordable healthcare for all. A straightforward automation solution is a conversion of the shape tracing tests from pen and paper to a mobile device. This study implemements realtime dynamic touch detection on a mid-range tablet for shape tracing. The tracing app developed was tested on 20 movement disorder patients and 10 control subjects. The results convey that the interface allows for successful self-administration of the tests. For all subjects, the accuracy was successfully preserved in the real-time dynamic acquisition of the tracing process.

I. Introduction

Dysfunctions in hand movements, such as tremor and rigidity, severely hamper a person's quality of life. These dysfunctions are often the first symptoms of neurological movement disorders, the most common of which are Parkinson's disease, Essential Tremor and Huntington's disease [1]–[3]. A common screening and assessment of movement disorders is the shape drawing test, which provides visual indications of the symptoms involved. The subject has to trace the line of a predefined object with a pen on paper whilst a clinician observes the subject doing so. These assessments are predominantly performed in medical facilities, as they necessitate the physical presence of a clinician [4]. As a result, the administration of these tests is costly, limited the accessibility to all, and their interpretation is inherently qualitative and subjective [5].