The Relationship Between Vibratory Perception Threshold, Joint Position Sense, and Loading Rate During Walking Gait in ACLR Individuals

Undergraduates: Sean Buitendorp, FJ Goodwin Dr. Brian Pietrosimone

Faculty Advisor: J. Troy Blackburn
Department: Exercise & Sport Science

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Anterior cruciate ligament (ACL) injury and surgical reconstruction (ACLR) increase the risk of knee osteoarthritis (OA). ACLR results in aberrant walking gait biomechanics that likely contribute to knee OA risk. In particular, higher loading rates have been observed following ACLR, and are associated with greater cartilage damage in animal models. ACLR individuals also demonstrate somatosensory deficits that may contribute to heightened loading rates. However, the relationship between somatosensory function and gait biomechanics has yet to be evaluated post-ACLR. Somatosensory function is measured in the laboratory via joint position sense (JPS). Vibratory perception threshold (VPT) may serve as a more clinically practical analog. The purposes of this study were to 1) compare somatosensory function (JPS and VPT) between the ACLR and contralateral limbs, 2) evaluate the relationship between JPS and VPT, and 3) evaluate the relationship between somatosensory function and loading rate during gait in individuals with ACLR. JPS, VPT, and gait biomechanics were assessed in 35 individuals with ACLR. JPS was assessed as the ability to reproduce a specified joint angle. VPT was assessed as the minimum detectable vibration amplitude applied to bony prominences in the lower extremity. Loading rate was assessed from force plates embedded in a walkway as the peak of the 1st time derivative of the vertical ground reaction force. Data collection is complete, and data analysis is ongoing.