Medicine and Health Sciences Commons^™

The Shared Contributions Of The Capsule, Labrum, And Bone On The Suction Seal Of The Hip, Alexander J. Hoffer

Electronic Thesis and Dissertation Repository

The hip capsule, labrum, and bone contribute to hip stability. Abnormalities in these structures are associated with pain and microinstability. Previous studies have quantified the individual stabilizing roles of the capsule and labrum and have associated cam over-resection with decreased hip stability.

The first objective of this thesis was to identify the relative biomechanical contributions of the capsule, labrum, and bone to the hip suction seal, as a representation of hip stability. The second objective was to assess the effectiveness of a labral reconstruction in restoring the suction seal after a cam over-resection.

Ten human cadaveric hips were tested in …

Biomechanical Characterization Of Semi-Rigid Constructs And The Potential Effect On Proximal Junctional Kyphosis In The Thoracic Spine, Chloe Cadieux

Electronic Thesis and Dissertation Repository

Long spinal fusions are the mainstay of treatment in adult spinal deformity; however, proximal junctional kyphosis (PJK) is a common and potentially catastrophic complication that can occur following this procedure. It has been hypothesized that using semi-rigid constructs at the superior aspect of the instrumentation may decrease this complication. The objective of this thesis was to determine if there is a biomechanical advantage between various semi-rigid constructs utilized in long spinal fusions to help decrease the risk of PJK. Nine human cadaveric spines (T1 – T12) instrumented with the standard all-pedicle-screw construct (APS) were compared to various semi-rigid constructs including …

Assessment Of Landing Biomechanics And Rehabilitation After Anterior Cruciate Ligament Reconstruction, Sheila S. Gagnon

Electronic Thesis and Dissertation Repository

Aberrant landing biomechanics increase the risk of anterior cruciate ligament (ACL) injury and are a focus of rehabilitation after ACL reconstruction. The purpose of the present thesis was to develop and evaluate methods of assessing landing mechanics and investigate the effects of different rehabilitation strategies after ACL reconstruction. Three studies were conducted. The first study used a Delphi process to develop the content of a Clinician-Rated Drop Vertical Jump Scale to evaluate jump landing mechanics during rehabilitation after ACL reconstruction. Twenty experts participated in four rounds of questioning, resulting in 92% agreement for knee valgus collapse, lateral trunk lean, insufficient …

Acromial Insufficiency Fractures In Reverse Total Shoulder Arthroplasty: A Biomechanical Study, Alicia Kerrigan

Electronic Thesis and Dissertation Repository

Reverse total shoulder arthroplasty (RTSA) is increasingly utilized in the aging population, with a growing list of surgical indications including rotator cuff tear arthropathy, proximal humerus fractures, and revision arthroplasty. Acromial insufficiency fractures following RTSA are poorly understood, difficult to diagnose, and associated with inferior clinical outcomes. There is limited knowledge in the literature regarding the etiology of post-operative acromial fractures. The purpose of this study is to evaluate the role of implant parameters on acromial strain following RTSA.

Using a cadaveric model, a custom designed modular RTSA system was implanted that allowed for evaluation of modifiable parameters including glenoid …

Constraining Kinematics During Single-Leg Squats And Step-Ups Can Reduce Quadratus Lumborum Activation And Facilitate Gluteal Activation, Shaylyn Kowalchuk

Electronic Thesis and Dissertation Repository

Increased quadratus lumborum activation and decreased gluteal activation may lead to lateral pelvic drop and increased hip adduction and internal rotation during single-leg exercises. These activation patterns and motions are associated with low back pain or lower extremity injuries. The purpose of this study was to evaluate if mechanically restricting hip adduction and internal rotation of the femur affected muscle activation. Twenty female track and field athletes performed single-leg squats and step-ups, and the quadratus lumborum, gluteus medius and maximus muscles activations were measured with surface electromyography. This study tested the hypothesis that mechanically restricted exercises would decrease quadratus lumborum …

Complex Shoulder Instability: The Role Of The Latarjet Coracoid Transfer, Ryan Degen

Electronic Thesis and Dissertation Repository

Recurrent anterior shoulder instability is a common clinical entity often requiring surgical stabilization. Recurrence rates following soft-tissue stabilization procedures are moderately high and have been attributed to associated bony defects of either the glenoid or humeral head. Complex shoulder instability, defined as instability associated with bony defects around the shoulder, is a challenging clinical problem. The Latarjet coracoid transfer has been proposed as a treatment option and its resultant stabilizing effects have been explored in this biomechanical cadaver-based study.

For both glenoid and humeral head defects, the Latarjet coracoid transfer adequately stabilized the shoulder, outperforming other procedures often utilized for …

Identifying Gait Abnormalities In Patients With Femoroacetabular Impingement Syndrome, Brook A. Russell

Electronic Thesis and Dissertation Repository

OBJECTIVE: To determine the biomechanical gait characteristics and quality of life of adults with femoroacetabular impingement (FAI) and how their gait compares to the gait of healthy controls. METHODS: Gait analyses were performed on 18 participants (9 FAI, 9 control) while walking barefoot in the Wolf Orthopeadic Biomechanics Lab. In addition, FAI participants completed general and region specific quality of life questionnaires. RESULTS: Hip moment (5.2%BW*ht vs. 4.96%BW*ht), toe out angle (12.36 ° vs. 8.15°), and lateral (3.55° vs. 2.18°) and forward (4.34° vs. 3.93°) pelvic tilt were not statistically different between groups. Trunk lean (1.33° vs. 0.36°), hip flexion …