Background
Telerehabilitation might be an intriguing option to improve and monitor early rehabilitation of anterior cruciate ligament reconstruction (ACLR). Despite its self-evident potential, data on validity and safety are scarce.
Objectives:
To assess the validity of a novel sensor-based application as an objective quantitative measurement tool on knee function during rehabilitation post ACLR in the ongoing ARCUS trial (DRKS 000024359) with regards to an international accepted measurement tool.
Design and Methods:
Prospective, longitudinal, randomized, single-centre clinical trial in patients with ACL reconstruction less than 6 months after injury.
Validation of combined measures: coordination, strength and agility tests, as well as range of motion (ROM), assessed with a sensor-based application (Orthelligent, OPED) at 3 (primary endpoint), 6 and 12 months with regards to the subjective International Knee Documentation Committee (sIKDC) score, Tegner, Lysholm, and Functional Movement Screen. Further, safety and risk evaluation were conducted. To identify independent determinants of sIKDC, multivariate linear regression analysis for various sensor data of different pre-defined exercises was performed.
Results
From July 2019 to December 2020, 67 patients planned for primary ACLR (70.1% male, age 25 years [21-32], IKDC 47 [30-59], Tegner 6 [4-7], Lysholm 56 [42-72]) were included. At three months, significant correlations were detected for active and passive ROM (r=0.460, p=0.0004, y=52.52+0.58*x and r=0.358, p=0.025, y=93.34+0.41*x respectively) regarding the subjective IKDC. Further, significant correlations were found for strength and agility via the vertical jump test (r=0.426, p=0.011, y=-41.99+2.78*x) and side-hop test (r=0.367, p=0.042, y=3.66+0.58*x), as well as for coordination via the Y-Balance test (r=0.579, p=0.0001, y=32.04+1.08*x). Regarding the secondary endpoint at six months, strong correlation was detected for side hop (r=0.539 (p=0.004), y= -40.52+1.12*x), vertical jump (r=0.444, p=0.018, y= - 1.4E2+3.95*x) and Y-Balance (r=0.499 (p=0.008), y= 25.27+0.95*x). Vertical jump (ß=0.39, T=2.4) and passive ROM (ß=0.35, T=2.2) were independent predictors of the sIKDC score at 3 months (p=0.003) and the side-hop test (ß=0.45, T=2.4) of the sIKDC at 6 months (p=0.22). Moreover no adverse events related to the use of the sensor-based application were reported.
Conclusion
For the first time we were able to demonstrate, validation of a digital sensor-based application to objectively quantify knee function. This will have further implications for clinical and therapeutic decision-making, quality control of rehabilitation measures, and offers great opportunities in developing further scientific research questions.