| Description |
Cam-type femoroacetabular impingement syndrome (FAIS) is a recently described pathology of the hip, characterized by reduced sphericity of the femoral head and pain during high range-of-motion activities. While cam FAIS is thought to be a major etiologic factor for the development of hip osteoarthritis, the natural history of cam FAIS is unknown. The over-arching objective of this dissertation was to address this knowledge gap by quantifying the morphological and biomechanical characteristics of cam FAIS. The aspherical femoral head in cam FAIS patients is thought to alter hip articulation patterns. However, the conclusions from studies evaluating hip kinematics in cam FAIS patients have been inconsistent. Unfortunately, skin marker motion capture is subject to substantial errors of up to 20° in rotation due to soft tissue artifact, and thus is likely not sufficient to study differences in hip motion between cam FAIS patients and control subjects. To this end, dual fluoroscopy has been used to quantify in-vivo hip kinematics during activities of daily living to within 1 mm and 1° in patients with cam FAIS. Measurements of morphology from radiographs are used to quantify femoral shape for diagnosis and to evaluate the sufficiency of surgical correction. However, there is little agreement as to which radiographic view provides the best visualization of the asphericity of the femoral head. Using statistical shape modeling, the specific shape variability of cam FAIS has been defined and used to evaluate various radiographic views on their ability to capture cam morphology. Importantly, insufficient resection is the most common reason for revision arthroscopy, indicating that further research on this topic is necessary. As such, cortical bone thickness was incorporated into statistical shape models to assess differences in cortical morphology that should be considered when investigating femoral resection and to evaluate whether cortical thickness could be used to guide the depth of surgical resection. Together, this work provided comprehensive measurements of hip morphometrics and biomechanics in patients with cam FAIS that improved our understanding of the role of morphology and movement patterns in FAIS hip joint degeneration. |
