Orthopedics 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 …

A Biomechanical Comparison Of A Subacromial Balloon Spacer, Superior Capsular Reconstruction, And A Rigid Subacromial Spacer In A Massive Irreparable Rotator Cuff Cadaveric Model, Devin Ferguson

Electronic Thesis and Dissertation Repository

Massive irreparable rotator cuff tears are a common cause of pain and disability. Several different treatments exist; however, they are associated with poor clinical outcomes and survivorship in younger patients without glenohumeral arthritis. The purpose of this thesis was to compare the impact of a subacromial balloon spacer, superior capsular reconstruction, and a rigid subacromial implant on the glenohumeral kinematics and mechanical efficiency of a massive rotator cuff deficient shoulder. The results indicate that each surgical state improves the glenohumeral kinematics of a massive irreparable rotator cuff tear. The subacromial implant leads to mild overcorrection of humeral head translation. No …

Assessing Inflammation In The Pathology Of Knee Osteoarthritis, Zachary J. Koudys

Electronic Thesis and Dissertation Repository

Osteoarthritis (OA) is a joint disease that causes pain, stiffness, and loss of function. Inflammation of the synovium plays a role in the pathology of OA. Macrophages are the dominant immune cells in synovial tissue. Activated macrophages over-express the translocator protein (TSPO). [¹⁸F]FEPPA is a 2^nd generation positron emission tomography (PET) tracer that can target TSPO with high specificity. Hybrid [¹⁸F]FEPPA PET/MRI may enable accurate quantification of macrophage activity in vivo. In this work, [¹⁸F]FEPPA tracer uptake in knee synovial tissue was measured ex vivo using autoradiography and was validated to correlate to …

Severe Lower Extremity Trauma In Ontario: A Linked Population-Based Analysis, Stephanie M. Kim

Electronic Thesis and Dissertation Repository

Open tibia fractures (OTF) are a management challenge. Admission to a trauma center (TC) and a coordinated approach to bony fixation and soft-tissue reconstruction (STR) have been shown to improve outcomes. The objective of this study was to describe patients who had OTF in Ontario and analyze their outcomes. Linked population data pertaining to patients who had OTF between the years 2009-2020 were examined. Demographic information, admission location, and management course were collected. 4240 patients were found. The mean age was 47, and majority were males. Patients admitted to TC had greater proportion of having Injury Severity Score >15, and …

Comparison Of Hip Navigation System Accuracy In Direct Anterior Approach, Jeremy Loh

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Introduction

Malposition of the acetabular component has been thought to have an influence on increasing increase the risk instability, impingement, and ultimately revision surgery. Hip navigation technology has been developed to provide the surgeon with real time intraoperative metrics to make critical decisions in implant placement. The goal of this study was to compare the accuracy of acetabular component positioning in direct anterior approach hip replacements using conventional fluoroscopy only technique, fluoroscopic image dependent navigation, and imageless navigation.

Methods

A retrospective data collection and prospective analysis was conducted for this study. After sample size calculations, fifty patients were collected for …

A Long-Term Follow-Up Of The Stability Study: Multicenter Rct Comparing Anterior Cruciate Ligament Reconstruction With And Without Lateral Extra-Articular Tenodesis In Individuals At High Risk Of Graft Failure, Katelyn M. Inch

Electronic Thesis and Dissertation Repository

One hundred and ninety-six patients at the Fowler Kennedy Sport Medicine Clinic (FKSMC) undergoing anterior cruciate ligament (ACL) reconstruction (ACLR) were randomized as part of the multi-center STABILITY study to receive either an isolated ACLR or ACLR with a lateral extra-articular tenodesis (LET). The STABILITY study followed these patients up to two years postoperative, and a long-term follow-up protocol was initiated afterwards. Eighty-two patients from this center were seen at three, five and seven years postoperative as part of a long-term follow-up. Our primary outcome was a composite outcome of instability and graft failure. Secondary outcomes included patient-reported outcome measures …

Total Hip Arthroplasty In Young Patients, Aaron G. Chen

Electronic Thesis and Dissertation Repository

Total hip arthroplasty (THA) is the gold standard in treatment of hip arthritis yet is often avoided in young patients due to concerns of inferior survivorship. We aim to explore the role of THA in young patients and assess whether these historical concerns are valid in contemporary THA by presenting the results of: (1) a systematic review and meta-analysis of the current literature, (2) a retrospective database review, and (3) a retrospective population-based study. We found excellent long-term survivorship with modern THA in young patients, demonstrating greater than 90% revision-free survival up to 15 years. Factors that may increase risk …

Decompression Vs. Decompression And Fusion In Cauda Equina Syndrome Secondary To Massive Lumbar Disc Herniation, Ruheksh Raj

Electronic Thesis and Dissertation Repository

Posterior spinal surgery through either a decompression or additional fusion procedure is the widely accepted standard of care for patients presenting with cauda equina syndrome (CES) secondary to massive disc herniation. A plethora of literature has been published regarding post- surgical outcome, particularly in regards to improvement of lower sacral nerve symptoms in relation to timing of surgery. There is a paucity of data with regards to long term clinical outcomes in patients between the decompression and decompression and fusion groups. We initially hypothesized was that there would be no longer term clinical differences in outcome between the two groups, …

Determination Of The Protective Capacity Of Hand Wraps In Combat Athletes Using Force Analysis, Eva M. Gusnowski

Electronic Thesis and Dissertation Repository

Upper extremity injuries are common in combat athletes, and are highest in the hand/wrist. Although protective hand gear is used, there is a paucity of research investigating its effectiveness. This study addressed this knowledge gap by measuring the level of force transmitted to the hand during striking using two types of hand wraps. This prospective cross over study included six combat athletes. A load cell was placed over the proximal phalanges/metacarpophalangeal joints and was used to measure sustained peak force during striking while covered with either standard linear or gel-reinforced hand wraps and boxing gloves. The gel reinforced wraps consistently …

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 …

Quantitative Mri And 3d-Printing For Monitoring Periprosthetic Joint Infection, Greg Hong

Electronic Thesis and Dissertation Repository

Joint replacements are becoming increasingly commonplace with over 130,000 joint arthroplasties being performed annually in Canada. Although joint replacement surgery is highly successful, implants do occasionally fail and need to be replaced via costly and difficult revision surgery. Periprosthetic joint infection (PJI) has recently become the leading reason for revision of both hip and knee replacements, which is unfortunate because PJI is difficult to diagnose and treat effectively; diagnosis is made particularly difficult by the lack of established non-invasive (imaging) means of evaluating PJI. This thesis aims to demonstrate that magnetic resonance imaging (MRI) has potential for diagnosing and monitoring …

The Biomechanical Effects Of Glenoid And Humeral Lateralization On The Rotator Cuff Muscles In Reverse Total Shoulder Arthroplasty, Yousif Atwan

Electronic Thesis and Dissertation Repository

The utilization of reverse total shoulder arthroplasty (RTSA) has continued to increase as its clinical indications expand. The optimization of the rotator cuff function in the setting of RTSA is poorly understood and poor outcomes are associated with lack of external and internal rotation function. The purpose of this study is to evaluate the role of implant parameters on rotator cuff tendon excursion and moment arms in the setting of RTSA.

Using a cadaveric based model, a custom designed modular RTSA system was implanted that allowed for incremental changes to glenoid and humeral lateralization. Using a shoulder simulator and optical …

The Natural History Of Modic Changes - A 5- And 15-Year Follow-Up Study, Parnian Saremi

Electronic Thesis and Dissertation Repository

Modic changes (MCs), defined as bone marrow lesions adjacent to the vertebral endplate seen on MRI, have been associated with back pain. There are different types of MCs, with different histopathological correlates. This community-based study sample comprised 110 men from the Twin Spine Study, with baseline, 5-year, and 15-year follow-up MRIs. Following training and reliability testing, 1320 endplates (T12-S1) were evaluated for MC presence, type, and dimensions at each time point. Results demonstrated that Type 2 Modic Changes (MC2) were the most common type, with approximately half located at the two lowest disc levels. However, Type 1 Modic Changes (MC1) …

Femoroacetabular Impingement Syndrome: Evaluating Postoperative Rehabilitation Progress And Return To Sport Readiness, Trevor A. Day

Electronic Thesis and Dissertation Repository

Femoroacetabular impingement syndrome (FAIS) is a common cause of non-arthritic hip pain and reduced physical activity in active young adults. It is defined as a motion-related disorder of the hip with a triad of symptoms, clinical signs, and imaging findings that represents symptomatic premature contact between the proximal femur and the acetabulum. There are two anatomical morphologies that can cause FAIS, cam, and pincer, and is a challenging clinical pathology. Patients typically undergo hip arthroscopy to repair damage to the joint and recess the bone causing the impingement. These procedures can result in positive outcomes for the patient, like reduced …

4dct Analysis Of In-Vivo Carpal Kinematics During Fem, Manisha R. Mistry

Electronic Thesis and Dissertation Repository

A consensus, detailed understanding of carpal kinematics remains elusive. 4-dimensional CT (4DCT) is a validated modality capable of accurately studying in-vivokinematic motion. The objective of this work is to quantify normal, in-vivo kinematic motion of the carpus through a flexion-extension arc of motion using 4DCT. Ten healthy, un-injured volunteers underwent a 4DCT scanning protocol through a complete arc of flexion-extension motion. Kinematic changes in motion were quantified using helical axis motion data for each carpal bone. Helical axes were compared between bones and statistical analysis performed using repeated-measures ANOVA to identify difference in kinematic motion between bones (p<0.05). The carpus can be divided into four main kinematic blocks: the distal carpal block, the proximal carpal block and individual scaphoid and trapezial blocks. This work supports an additional segmentation of the trapezium from the distal carpal row, which suggests some modulation between the scaphoid and distal carpal row.

Kinematics In Total Knee Arthroplasty, Allan Roy Sekeitto

Electronic Thesis and Dissertation Repository

Total knee arthroplasty (TKA) continues to be a successful procedure for the past 50 years. We investigated the kinematics after under- and overstuffing the joint space with the polyethylene (PE) insert in both cruciate-retaining (CR) TKA and posterior-stabilized (PS) TKA. We compared CR and PS designs to evaluate their respective kinematic differences. This study employed a hybrid computational-experimental joint motion simulation on a 6 degrees of freedom joint motion simulator. Physical prototypes of a virtually performed TKA based on cadaveric CT scans and a virtual ligament model were utilized. We demonstrated understuffing decreases stability and the joint compressive forces, with …

Biomechanical Strategies To Reduce Subsidence In Posterior Lumbar Interbody Fusion Procedures, Renan Jose Rodrigues Fernandes

Electronic Thesis and Dissertation Repository

Posterior approaches remain among the most used to perform lumbar interbody fusion (LIF) surgery. It happens because of the advantage of providing direct access to the neural elements in the lumbar spine and the surgeons' preference for the approach. But the interbody fusion devices (IFD) inserted using posterior approaches are of limited size, and implant subsidence remains the most common complication after LIF surgery. It can be catastrophic for the patient resulting in worse outcomes or even requiring revision surgery. Since increasing the cage's size is not possible in PLIF surgeries, this thesis will explore biomechanical strategies to increase the …

Exploring Methods For Improving Baseplate Fixation In Reverse Total Shoulder Arthroplasty, Sejla Abdic

Electronic Thesis and Dissertation Repository

Improving the success of modern reverse shoulder replacements is dependent on optimal initial baseplate fixation. A cadaveric biomechanical investigation examined how peripheral screw position and orientation affect baseplate fixation in normal glenoids. The results show no statistically significant difference between screw position (p=.60) or orientation (p=.20) regarding baseplate micromotion in the non-eroded glenoid. In a subsequent study to determine best management in pathologic baseplate fixation, a computer-model was employed to quantify the erosion in the E2 type glenoid. In the E2 type glenoid, erosion was found to be oriented postero-superiorly and covering an average of 66% of the surface area …

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 …

Reducing Length Of Stay After Total Hip And Knee Arthroplasty: Assessing Cost-Effectiveness, Caregiver Involvement And Surgical Approach, Bryn O. Zomar

Electronic Thesis and Dissertation Repository

Purpose

The overall purpose of this dissertation was to evaluate factors related to reducing length of stay after total hip and knee arthroplasty (THA and TKA).

Methods

Study 1 was a randomized controlled trial (RCT) to investigate the cost-effectiveness of outpatient THA compared to standard overnight stay. Study 2 was a prospective cohort study to assess patient- and caregiver-related factors and how they may relate to caregiver strain and level of assistance when caring for patients undergoing THA and TKA. Finally, Study 3 was a 2x2 factorial RCT to compare the trajectory of early functional recovery between the medial parapatellar …

Lateral Subvastus Lateralis Versus Medial Parapatellar Approach For Total Knee Arthroplasty, Sahil Prabhnoor S. Sidhu

Electronic Thesis and Dissertation Repository

The current gold standard surgical approach for Total Knee Arthroplasty (TKA) is a medial parapatellar approach (MPA). We aimed to study a novel lateral subvastus lateralis approach (SLA) for TKA and compare patient outcomes and joint kinematics to the MPA.

Patients with neutral or varus alignment undergoing primary TKA were recruited to undergo the SLA. At one year postoperative, patient outcomes (WOMAC, SF-12, KSS) and joint kinematics (using radio stereometric analysis (RSA)) were analyzed. 7 LPA and 7 MPA patients were compared.

The SLA resulted in improved medial femoral rollback early in flexion, but less “regular” (external) rotation of the …

Joint Protection Programs For People With Hand Arthritis, Pavlos Bobos

Electronic Thesis and Dissertation Repository

The fact that Joint Protection Programs (JPP) can reduce pain and improve function is based on small, but definitive Randomized Controlled Trials (RCTs), conducted in the 1980s. However, changes over time in the nature of hand use, the rapid expansion of technology, and improvements in our understanding of health literacy mean that these programs are now outdated. Further, problems with adherence to JPP are well documented. The purpose of this thesis was 1) to conduct a scoping review to map all the available evidence around joint protection programs in published and unpublished studies 2) to evaluate the effectiveness of joint …

Navigation And Patient Specific Instrumentation In Shoulder Arthroplasty, Joseph Cavanagh

Electronic Thesis and Dissertation Repository

The humeral head osteotomy influences shoulder arthroplasty component height, version and neck shaft angle and therefore outcomes. The purpose of this study is to develop and utilize navigation to execute the osteotomy.

3D printed models were used to develop a navigation technique, and then to execute planned osteotomies. Free hand, fixed angle guide, patient specific guides, and real time navigation osteotomies were completed. The height, neck shaft angle and version were recorded. Also collected, were the planes of the guides once they were placed.

Navigation had significantly less error from the planned osteotomy in neck shaft angle versus all other …

Biomechanical Analysis Of Total Knee Arthroplasty Performed On A 6 Degree Of Freedom Joint Motion Simulator Linked To A Virtual Ligament Model In Mechanical And Kinematic Alignments, Jance Mcgale

Electronic Thesis and Dissertation Repository

Total knee arthroplasty (TKA) is a very successful surgery providing many patients with increased quality of life. Despite this, some patients are dissatisfied. There are also complications with total knee arthroplasty that lead to the need for revision surgery. Improvements in stability, soft tissue balance, joint kinematics and overall patient satisfaction may lead to a decrease in TKA revisions. It is still unclear what the optimal soft tissue tension, balance or alignment is to provide superior patient outcomes. Computational models provide a means to effectively parameterize ligaments and simulate multiple scenarios of TKA. This work implemented a sophisticated 6-degree of …

A Clinically Representative Rat Model Of Hip Hemiarthroplasty, Adam Dm Paish

Electronic Thesis and Dissertation Repository

Joint replacement is an increasingly common surgery with over 130,000 procedures performed annually in Canada. Although joint replacement surgery is highly successful, implants do not last a lifetime, and often have to be replaced via costly revision surgeries. Before innovations aimed at extending the life of implants are applied to the clinic, testing must be performed in animal models. Clinically representative small-animal models of joint replacement would be ideal in the initial stages of research and development, due to ease of handling and low costs, but few such models have been established in the literature. Thus, we describe the development …

A Biomechanical Investigation Into The Effect Of Experimental Design On Wrist Biomechanics And Contact Mechanics, Clare E. Padmore

Electronic Thesis and Dissertation Repository

The wrist is one of the most commonly injured joints, and injury can have serious sequelae if pathological healing ensues. Strides have been made to understand normal and pathological wrist biomechanics using experimental approaches, which has contributed to improved patient care. The present work advances our understanding of the influence of experimental techniques and joint motion measurement techniques on in-vitro wrist biomechanical cadaveric studies, and applies the knowledge learned to a common clinical entity of scapholunate insufficiency.

First, the relative contributions of the carpal rows to wrist motion were assessed, in addition to the identification of limitations of current biomechanical …

Microorganisms In Presumed Aseptic Revision Hip And Knee Arthroplasty, Michael E. Neufeld

Electronic Thesis and Dissertation Repository

The role and clinical significance of microorganisms in presumed aseptic revision total hip (THA) and knee arthroplasty (TKA) is unclear. The primary aim of this thesis was to determine the prevalence and infection-free survival of presumed aseptic revisions with unexpected positive intraoperative cultures (UPC) by analyzing the largest cohorts of UPC in the literature. Secondarily, a prospective pilot study using modern molecular techniques with an emphasis on stringent control of contamination was designed to determine how frequently microorganisms are present on implants of presumed aseptic revisions, as well as their location and association with reason for revision.

The prevalence of …

Synergistic Effects Of Non Contact Induction Heating & Antibiotics On Staphylococcus Aureus Biofilm, Rajeshwar Singh Sidhu

Electronic Thesis and Dissertation Repository

Staphylococcus aureus is a major cause of prosthetic joint infection (PJI) in which it forms adherent biofilms, thick aggregates of extracellular polymeric substances (EPS) produced by the bacteria. Biofilm associated infections are difficult to treat as they have increased resistance to various antimicrobial agents, which means infected implants often require multiple procedures and prolonged antibiotic therapy. However, a new and emerging method of treatment of PJI is non-contact induction heating (NCIH) of metal implants. We sought to investigate the feasibility and effectiveness of NCIH along with synergistic effects of antibiotics (Vancomycin) in reducing bacterial load within surface associated biofilms in …

The Of Application Of 3d-Printing To Lumbar Spine Surgery, Andrew J. Kanawati

Electronic Thesis and Dissertation Repository

Rapid prototyping refers to the manufacturing process in which a three-dimensional (3D) digital model can be transformed into a physical model by layering material in the shape of successive cross sections atop of previously layers. Rapid prototyping has been increasing in popularity in the field of medicine and surgery due to the ability to personalize various aspects of patient care. The thesis will explore the use of rapid prototyping in lumbar spine surgery, aim to quantify the accuracy of medical imaging when relating to imaged structures and their corresponding models produced by rapid prototyping, and determine if complex patient-specific guides …

Biomechanics Analysis Of Anterior Cortical Perforation In Antegrade Femoral Nailing, Michael Ching

Electronic Thesis and Dissertation Repository

Hip and femur fractures are a common problem in an aging population. The number of hip and femur fractures are on the rise in Canada. Cephalomedullary fixation is a common method of treating hip and femur fractures, with a known complication of anterior cortical perforation of the distal femur. The literature describes risk factors, such as the influence of the start point at the greater trochanter, but there is no consensus on management. Some cases are treated with restricted weightbearing and other cases with revision surgery. Restricted weightbearing increases perioperative complications including mortality and decreases functional outcomes.

We analyze the …