BIOMECHANICAL CONSIDERATIONS FOR NEUROMUSCULAR CONTROL OF KNEE ARTHROPLASTY PATIENTS AND PROPRIOCEPTION OF HEALTHY PARTICIPANTS

Abstract

Knee osteoarthritis (OA) patients often experience significant limitations in walking and stair negotiation abilities. Total knee arthroplasty (TKA) and unicompartmental knee arthroplasty (UKA) patients are frequently unable to ascend and/or descend stairs due to pain, limited pre- and post-operative range of motion, or poor limb coordination associated with diminished quadriceps performance. Three-dimensional (3D) biomechanical gait analysis has served as a measurement technique to assess these pre- and post-operative functional deficits. Through the use of 3D biomechanical analysis, various indicators of knee OA progression and development, as well as risk of revision, have been established with external knee adduction moment (KAM) and knee flexion moment (KFM), among others. Though these risk factors are adequate in predicting medial loading and willingness to load the limb, respectively, they are not sufficient in determining pre- and post-operative neuromuscular control deficiencies. Longitudinal analyses of time-derivatives for frontal and sagittal plane measures of knee joint loading, as well as aggregate measures of leg stiffness are examined in this dissertation. These areas have been less well studied in this population and may further explain neuromuscular deficits from a biomechanical perspective. To further examine how biomechanical variables may explain neuromuscular control, this dissertation also includes a cross sectional analysis of knee joint proprioception, specifically joint position sense (JPS), in several testing positions for a healthy cohort. Several analyses were conducted to examine any differences in JPS between limbs, and associations between biomechanical measures of loading and knee joint proprioception in healthy individuals. Given the lack of evidence examining these associations, these analyses were largely exploratory; however, hypothesis driven analyses were conducted. The novel findings of this dissertation inform on these associations (or lack thereof) and provide insight into longitudinal gait changes between TKA and UKA patients. The results also inform on neuromuscular considerations for knee biomechanics in these patients during stair negotiation and level walking.