Development Of A Sensor-Based Measurement System For Square Hop Testing: A Feasibility Study

Background Knee and ankle injuries are among the most common injuries in football, basketball and handball. After an injury, movement-related functions and structures must be examined and deviations from the norm identified. Functional testing procedures are increasingly being used for this purpose. Based on the test results, the rehabilitation process can then be systematically controlled and individually adapted. Jumping ability in multidirectional movement can be measured with the Square Hop Test (SHT). Jump tests are usually carried out under visual control. However, this approach may be prone to errors due to its subjectivity. In order to compensate for the disadvantages of conventional data collection and to objectify data collection, the aim of this work was to construct a prototype that automates data collection and data evaluation of SHT using a sensor-based method. Methods The development of medical devices initially requires feasibility studies (proof of concept) in the early phase of clinical testing. Proof of concept (PoC) is used to check the requirements of the application and for the initial collection of data. With the help of the PoC, the material was determined, checked and adjusted. In addition, data collection and data analysis were tested using a microcontroller. For this purpose, test jumps were carried out. No patent research was carried out. Results The tester can access a test protocol using any internet-enabled device. The final prototype has a size of 22x22 conductive copper tracks and therefore 484 measuring points. The measurement system measures valid and faulty jumps and quantifies side differences of the extremities using the Leg Symmetry Index. The duration of the test is 30 seconds; every crossing of the lines counts as a valid jump and a jump that touches the lines is counted as an error. Discussion The use of sensor-based measurement systems can help to objectify clinical data collection through the automated measurement of valid and incorrect jumps and thus make diagnoses more precise. Weaknesses of manual test execution are thus overcome with the sensor-based SHT. In addition, such a measurement system enables the combination of qualitative and quantitative assessment criteria, for example by displaying a jump image. In further studies, test quality criteria such as validity and reliability of the sensor-based SHT must be determined. Conclusion for practice A sensor-based measurement system can be used to automate the collection and evaluation of the SHT data. Sensor-based SHT can potentially help increase the certainty of important decisions in the rehabilitation process for lower extremity injuries regarding exercise capacity or sport ability. This could have a beneficial effect on the further course of rehabilitation.