The prosup app ; a reliable application for measuring prosupination of the lower arm

Decrease in supination and pronation is a well-known phenomenon after both-bone
ante-brachii forearm fractures. A fracture might lead to a limitation of the
rotation of the forearm, resulting in decreased pronation and supination. This
decreased function is often precluded. It is desirable to maintain a full range
of motion to allow for daily activities. Currently the clinical golden standerd
for prosupination is a visual estimation with the Universal Goniometer (UG).
The most accurate measure device is a mechanical goniometer in the motionlab
in the Technical University of Delft, the biometrics ltd. apparatus. This
machine gives the most reliable measurements, but it applicable in the clinical
setting. This golden standard can be used to validate the application. Pitfalls
of the current method are; visual malestimation, by wrong execution of the test
by the patient, or wrong execution of the test by the physician (Behnoush, et
al. 2016). Smartphones are being implemented in medial care more and more.
Therefore we conducted a search of literature for smartphones as a tool for
accurate measurement of angles. A study of Behnoush et al, showed different
methods of measuring ROM of the shoulder. They compared the smartphone to the
UG and we compared and they found that the use of a found that the smartphone
was at least as accurate as the UG. The purpose our study was determine if our
prosup application is as reliable as the currently applied UG or the technical
golden standard goniometer for measuring pronation and supination of the
forearm as well in adults as in children.
First we designed an application for android smartphones. This application was
compared to the golden standard the biometrics ltd. apparatus. Than followed by
designing a prototype wristband. The ideal position of the wristband on the
wrist was determined, with the most stable position on the lowerarm, and the
lowest measurements error. This was done by positioning the wristband on
different positions on the lower arm, flexing the muscles and register how much
this affected the measured values. The best position was on the radial side of
the wrist. The prototype was tested on three test persons to determine the
accuracy of the measurements of the application. Finally an inter observer
reliability was conducted to determine if our application is a reliable
replacement for the current goniometer and the biometrics ltd. apparatus golden
standard .
The next aim of our study is to test our application and wristband on 100 test
persons, on the affected arm and the non-affected contra-lateral arm. And
compare these measurements to the currently used UG measurements. All done in
triple and by two investigators. Validating our application and preparing It
for clinical use.

Primary objective; To asses the accuracy and precision, the criterion validity
of the app compared to the goniometer and the inter and intra observer
reliability
Secondary objective; To evaluate the applicability of the PROSUP mobile phone
application for children with a lower arm injury with evaluation
forms.

Clinical research in which patients will undergo a prosupination measurement
during their normal follow-up after trauma to the forearm. Patients can be
included after plaster removal / pressure bandage.
Involved arm; 2 researchers / 3x measurement with the application and the
goniometer. Unaffected arm; 1 researchers / 1x measurement with the application
1x the goniometer.
Order of measurements will be randomized using a computer application.
A total of 9 measurements. This way we can calculate the intra- and
interobserver reliability.
And compare this app with the currently used golden standard the goniometer.
Evaluate the user friendlyness of the PROSUP mobile application with evaluation
forms.

none, low burden