Low-cost tele-assessment system for home-based evaluation of reaching ability following stroke

Abstract

Objective: Tele-assessment techniques can provide healthcare professionals with easily accessible information regarding patients' clinical progress. Recently, kinematic analysis systems have been used to assess rehabilitative outcomes in stroke patients. Kinematic systems, however, are not compatible with tele-assessment. The objective of our study was to develop a tele-assessment system for acquiring kinematic data of forward reaching movements in stroke patients, with an emphasis on cost-effectiveness, portability, and ease of use.

Materials and methods: We selected four healthy control participants and eight hemiplegic stroke patients for our study. The stroke patients were classified as Brunnstrom stage III, stage IV, or stage V. Our tele-assessment system used two three-axes accelerometers, a potentiometer, a multifunctional data acquisition card, and two computers. A standardized kinematic system was applied simultaneously to validate the measurements recorded by our tele-assessment system during five repetitions of forward reaching movements.

Results: The correlation coefficients of the reaching displacement, velocity, and acceleration measurements obtained using our tele-assessment system and the standardized kinematic system were 0.956, 0.896, and 0.727, respectively. Differences in the maximum reaching distance and the maximum reaching velocity of forward reaching movements were observed among the study groups. There were no significant differences in the time required to complete the testing session among the study groups.

Conclusions: Our tele-assessment system is valid for the evaluation of upper-extremity reaching ability in stroke patients. Further research is needed to investigate the feasibility of the use of the tele-assessment system in patients' homes.

Fig. 1.

Illustration of the tele-assessment system showing the remote acquisition of forward reaching data in the patient's home and the transmission of the data from the patient's remote computer to the clinician's computer via the Internet.

Fig. 2.

Diagram of the forward reaching measurements. The open circles (numbered 1 and 2) represent the accelerometers. The open square represents the stationary end of the potentiometer, and the solid square represents the movable end of the potentiometer. The positions of the participant's arm and the moveable potentiometer before the reaching movement are represented in stippled lines.

Fig. 3.

Five repetitions of the forward reaching movements of a healthy control were recorded simultaneously using our tele-assessment system and the FASTRAK system, and the reaching distance waveforms were superimposed to demonstrate the validity of our tele-assessment system.

Fig. 4.

The patterns of the forward reaching movements of Brunnstrom stage III–IV stroke patients and control participants. The signal was generated from the amplitude values recorded by the potentiometer as the distance between the moveable and fixed ends changed during the forward reaching movements. The smoothness of the reaching pattern was obviously different for each group.

Fig. 5.

Reaching movement characteristics of each study group: (a) the maximum reaching distance, (b) the maximum reaching velocity, and (c) the time required to complete the testing sessions are represented. Data are mean±standard deviation values.