Date of Award


Degree Type


Degree Name

Master of Science


Health and Human Performance


Exercise Science

First Advisor/Chairperson

Sarah Clarke


Study Design: Quasi-experimental. Objectives: To compare clinical and mechanical measures in detecting lower limb asymmetries associated with second anterior cruciate ligament (ACL) injuries. Background: Knee extension moment (KExtM) asymmetry is predictive of second ACL injury. Evaluation of clinical return to sport tests to assess and classify asymmetry is needed. Methods: While performing the drop vertical jump (DVJ), thirty healthy individuals underwent 3D motion analysis. Absolute difference in KExtM between limbs at initial contact of the DVJ (KExtM symmetry) was calculated separately for each trial and averaged. Subjects performed single leg hop (SLH) and Y-Balance tests (YBT). Limb symmetry index (LSI) and absolute difference in anterior reach distance (ANT RD) between limbs were used for SLH, and YBT symmetry measures; respectively. Pearson’s correlation assessed the relationship between LSI, YBT, and KExtM symmetry. Confusion matrices were used to illustrate classification accuracy. Results: A moderate negative correlation (r = -0.418, p= 0.022; 95% CI = -0.68, -0.07) existed between LSI and KExtM symmetry. A weak negative correlation (r = -0.377, p = 0.040; 95% CI = -0.65, -0.02) existed between ANT RD and KExtM symmetries. LSI and ANT RD symmetry demonstrated no true positives in symmetry classification. Conclusion: Although LSI and ANT RD were related to KExtM symmetry, both tests failed to correctly classify asymmetries.