Doctor of Physical Therapy (DPT)
First Committee Member
Second Committee Member
Number of Pages
Objective: To examine the reliability and validity of using a movement analysis application (MAA) to measure knee valgus angle during three functional activities used to assess return-to-sport after ACL reconstruction (ACLR). Design: Reliability and validity study Setting: University laboratory Participants: Twelve ACLR participants with a non-contact mechanism of injury and 20 healthy individuals. Independent Variables: Each subject performed single-leg drop landing, single-leg hop, and 90º cut with simultaneous 3-dimensional (3D) motion capture and video recording in the frontal plane on an iPad. Main Outcome Measures: Peak knee valgus angle during the landing phase of each task was measured using a MAA and 3D analysis. To obtain reliability, peak knee valgus angle was measured in 2 days with at least 7 days apart. Reliability was determined using intra-class correlation coefficients (ICCs) and standard errors of measurement (SEMs). Validity was assessed using Pearson correlation coefficients by comparing peak knee valgus angles between the MAA and 3D analysis. Results: Our data revealed excellent intra- and inter-rater reliability with low SEMs of using a MAA for evaluating peak knee valgus angle in both groups. Significant, moderate to large associations were found in comparing peak knee valgus angles between the MAA and 3D analysis in both groups. Conclusions: Our findings suggest that a MAA is reliable for measuring peak knee valgus angle for both healthy and ACLR participants. The actual values obtained by a MAA should be viewed with caution given that the comparison against the 3D motion analysis is moderate to large.
Reliability; Validity; Anterior cruciate ligament; Movement analysis application; Knee valgus
University of Nevada, Las Vegas
Benson Deaver, Brenda and Nelson, Tyrel, "Reliability and Validity of using a Mobile Application to Asses Knee Valgus in Healthy and Post-Anterior Cruciate Ligament Reconstruction Participants" (2018). UNLV Theses, Dissertations, Professional Papers, and Capstones. 3561.