Chloe Glubka, “Precision and Reliability of Foot Posture Assessment Using a Seven Segment MSF Model”
Mentor: Stephen Cobb, Kinesiology
Abnormal foot posture is associated with a multitude of lower extremity injuries. Clinicians use various methods to quantify foot posture, however, the between- and/ or within- tester reliability of many of the measurements is low, limiting their clinical application. Navicular index and arch angle are two measurements identified as having moderate reliability between- and/ or within- testers. The purpose of this study was to investigate between- and within- tester precision and reliability of the two measures assessed using a multi-segment foot model. Ten healthy adults (ages 18-44) participated in the study. Tester one palpated and marked the anatomical landmarks and then recorded their positions using a motion capture system. All markers were removed and tester two repeated the procedure. Each participant returned in one week for a second assessment. Precision measurements for between- and within- testers was calculated using the root mean square of the deviation between the positions of the anatomical landmarks in a trial and the landmarks mean position. Within- and between- tester reliability was calculated using intraclass correlation coefficients. Within- and between- testers precision for the navicular index was 0.013 ± 0.003 and 0.016 ± 0.007, respectively. Within- and between- tester precision for the arch angle was 3.6 ± 0.8° and 5.2 ± 2.8°, respectively. Within- and between- tester reliability for navicular index (within ICC: 0.76; between ICC: 0.71) was moderate to good (ICC >0.5). Within- and between- tester reliability for arch angle (within ICC: 0.25; between ICC: 0.3) was poor (ICC <0.5). The multi-segment foot model used in this study can be used to precisely and reliably measure the navicular index. However, the precision and reliability of using the model to measure arch angle was poor. Further research is needed to investigate alternative methods of using the model to quantify arch angle.
Click here for the full version of the poster to follow along.
Hello!
My name is Chloe Glubka, I am a senior majoring in Kinesiology and have been working in Dr. Cobbs lab for the past year and a half. Thank you for taking your time to learn about quantifying precision and reliability with the MSF model. Any questions and comments are welcome!
Great presentation, Chloe! Very interesting work as well. I’d be interested to know which lower extremity injuries are associated with the measures included in your study and if there are clinical implications to your findings? Perhaps the not-so-reliable nature of measuring the arch angle will impact injury risk assessment? Really cool work!
Hello! Some examples of lower extremity injuries include plantar fasciitis and stress fractures. Currently, a specific injury cannot be correlated to a certain foot posture as we are working to define normal and abnormal foot postures. Once foot posture has been universally quantified within- and between- testers, we can work clinically to apply foot posture with specific lower extremity injury.
Very interesting! Is there a possibility that some of the within-tester variability is caused by actual changes to the measurements over time?
Hello! The variability within- testers is thought to be caused by inconsistencies with marking the anatomical landmarks. One factor of this is skin movement. As the participants were all adults and the two trials were conducted within a week of each other, there should not be within- tester variability from changes to the measurements from factors such as foot growth or structure change.