Evaluating the reliability of four-dimensional computed tomography scans of the wrist

Introduction: Four-dimensional CT (or 4D CT) scans are a novel approach to diagnosing musculoskeletal pathology. Although still in its infancy, there has been a surge of interest in identifying clinical applications for musculoskeletal 4D CT. The scapholunate joint has received the most attention thus far due to the complex articulations and challenges faced with prompt diagnosis of scapholunate injuries. The objective of this thesis is to review current literature on musculoskeletal 4D CT and to evaluate the inter- and intra-rater reliability of the assessment of scapholunate stability in 4D CT wrist scans. Methodology: 4D CT scans of thirteen healthy volunteers and four patients were prepared. Seven orthopaedic and plastic surgeons were recruited to qualitatively assess the stability of the scapholunate joint in the 4D CT scans. Statistical analysis included percent agreement, Fleiss’ kappa, and Gwet’s AC1 coefficient. Results: The percent agreement amongst all raters was 0.80392 (95% CI: 0.675 - 0.932). Fleiss’ Kappa was 0.54895 (95% CI: 0.252 - 0.846) and Gwet’s AC₁ was 0.54895 (95% CI: 0.391 - 0.915). The intraclass correlation coefficient (ICC) for intra-rater reliability was 0.71631 (95% CI: 0.5567 – 0.8423). Conclusion: Our pilot study suggests good inter- and intra-rater reliability for the qualitative assessment of scapholunate instability in 4D CT scans. Although further studies are required, this thesis highlights the vast potential of 4D CT as a non-invasive diagnostic technique of dynamic musculoskeletal injuries

A Biomechanical Investigation into the Effect of Experimental Design on Wrist Biomechanics and Contact Mechanics

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 testing techniques. The radiocarpal joint contributed more motion to wrist flexion, the midcarpal joint contributed more to wrist extension, while near neutral wrist position there was a relatively equal contribution from both joints. Passive motion joint simulation, forearm position, and coordinate system selection and joint congruency were all identified as areas needing investigation. In order to assess the effect of joint coordinate system (JCS) selection on resulting wrist angle, four JCS were compared to determine JCS selection on wrist angle characterization. Subtle differences were found between JCSs, and the findings support the use of any of the analyzed methods. Additionally, to quantify joint congruency at the wrist, validation and application of a previously described a non-invasive CT-based technique to measure joint congruency at the wrist is described. The effect of forearm orientation on wrist joint biomechanics was then evaluated. Radioscaphoid joint contact was found to be sensitive to forearm orientation and wrist angle, while radiolunate joint was not sensitive to changes in forearm orientation. Scaphoid angular rotation was found to vary with forearm position, but only at the extremes of wrist flexion-extension. The present work advances wrist biomechanics knowledge and will help to improve the clinical management of acute and chronic wrist injuries

Imaging of Osteoarthritis and Rheumatoid Arthritis in Hand Joints

The aims of this thesis can be summarized as: - to assess construct validity and reliability of direct cartilage imaging with MRI in hand OA. - to asses if CT has better reliability and detection rate of thumb base OA than conventional radiography. - to assess construct validity of low-field extremity MRI in early arthritis patients

THE DESIGN AND VALIDATION OF A COMPUTATIONAL MODEL OF THE HUMAN WRIST JOINT

Advancements in computational capabilities have allowed researchers to turn towards modeling as an efficient tool to replicate and predict outcomes of complex systems. Computational models of the musculoskeletal system have gone through various iterations with early versions employing dramatic simplifications. In this work, a three-dimensional computational model of the wrist joint was developed. It accurately recreated the skeletal structures of the hand and wrist and represented the constraints imposed by soft tissue structures like ligaments, tendons, and other surrounding tissues. It was developed to function as a tool to investigate the biomechanical contributions of structures and the kinematic response of the wrist joint. The model was created with the use of a commercially available computer-aided design software employing the rigid body modeling methodology. It was validated against three different cadaveric experimental studies which investigated changes in biomechanical response following radioscapholunate fusion and proximal row carpectomy procedures. The kinematic simulations performed by the model demonstrated quantitatively accurate responses for the range of motions for both surgical procedures. It also provided some understanding to the trends in carpal bone contact force changes observed in surgically altered specimens. The model provided additional insight into the importance of structures like the triangular fibrocartilage and the capsular retinacular structures, both of which are currently not very well understood. As better understanding of components of the wrist joint is achieved, this model could function as an important tool in preoperative planning and generating individualized treatment regiments

Utilizing Geographic Information Systems to Record and Analyze Osteoarthritis Data in Joints of the Arm: A Methodology for Dry Bones

Osteoarthritis (OA) is one of the most common pathologies encountered in dry bone contexts. However, even with the wealth of publications on documenting the presence of OA from skeletons, these studies prove to be largely incomparable due to different scoring methodologies and procedures in calculating prevalence. The standardization of a new OA data collection procedure would mitigate variability in evaluating, scoring, and calculating the prevalence of OA, thus allowing accurate comparison between studies. However, this level of data collection has often been described as unwieldy and lacking concordance. This research outlines a new methodology that utilizes Geographic Information Systems (GIS) to record OA characteristics, levels of expression, and spatial arrangement on the articular surfaces of the arm. The data was then processed using the analysis and visual rendering capabilities of GIS providing examples of OA patterning on the articular surface, within the joint, and within the individual. Using this method, large standardized OA datasets can be stored and the patterns within them modeled through the use of digitization, composite raster overlays, and modified binning techniques. The patterns recorded by this analysis can offer a more robust dataset on OA occurring within the arm that can provide the ability to explore OA progression and its relationship with biomechanical factors in larger datasets

Outcomes and challenges in ulnar-sided wrist surgery

The findings in this thesis underlined the confounding nature of ulnar-sided wrist pain. It is crucial to be aware of the complex overlap and interaction of the pathologies at the ulnar wrist, to guide accurate diagnosis. Relevant diagnostic imaging can assist in establishing the right diagnosis and exclude other pathology. However, it must be noted that each modality has its own specific indications and set of advantages and disadvantages. Furthermore, it may be difficult to differentiate structural sources of ulnar-sided wrist pain from unrelated incidental findings, which once again highlights the importance of taking a thorough history and performing a detailed physical examination. We stated that PROMs can assist in the development of a treatment plan to meet the specific preferences and needs of a particular patient, as they quantify care from the patient’s perspective. In this thesis we found relatively high rates of complications and reoperations after ulnar-sided wrist surgery. However, these high rates did not always necessarily lead to inferior patient-reported outcomes. We believe that psychological factors and coping strategies have a great influence on level of pain and physical functioning. Advances in medical imaging technology with the use of artificial intelligence (AI) in radiology and new techniques such as 4D-CT, may allow improved assessment of wrist kinematics and pathology in ulnar-sided wrist pain. Furthermore, there is growing evidence for a strong influence of psychosocial factors on PROMs across a range of upper-extremity disorders. We believe that that there is more to generating optimal outcomes than resolving pathophysiology, restoring anatomy, and focusing on the technical components alone. More large-scale and prospective studies are required to compare several ulnar-sided wrist procedures, ideally with implementation and a great focus on the influence of psychological and social factors

Osteoarthritis

Osteoarthritis is one of the most debilitating diseases affecting millions of people worldwide. However, there is no FDA approved disease modifying drug specifically for OA. Surgery remains an effective last resort to restore the function of the joints. As the aging populations increase worldwide, the number of OA patients increases dramatically in recent years and is expected to increase in many years to come. This is a book that summarizes recent advance in OA diagnosis, treatment, and surgery. It includes wide ranging topics from the cutting edge gene therapy to alternative medicine. Such multifaceted approaches are necessary to develop novel and effective therapy to cure OA in the future. In this book, different surgical methods are described to restore the function of the joints. In addition, various treatment options are presented, mainly to reduce the pain and enhance the life quality of the OA patients

The role of ultrasonography in the investigation and management of rheumatic conditions

Aims: The importance of inflammation in the development of joint damage and subsequent functional limitation, together with the increasing awareness that clinical assessment is insensitive at detecting synovitis, has led to the use of modern imaging modalities such as ultrasonography (US) in rheumatology. This with an emphasis on improved detection of synovitis and earlier, more effective therapeutic intervention. The aim of this thesis was to investigate the role of US in routine practice, by validating its role in diagnosis, prognosis and therapeutic intervention, across a range ofcommon rheumatological clinical scenarios. Methods: Construct validity for US-detected synovitis in knee arthritides was examined by comparison with clinical assessment and arthroscopy. In order to examine the benefits of US-guided joint injections, the accuracy of guided shoulder injections was observed. As well, the efficacy of US-guided corticosteroid injections in hip osteoarthritis and predictors of outcome were also assessed. The sensitivity of US over clinical examination was assessed in a cohort of rheumatoid arthritis patients with low disease activity levels. The diagnostic and therapeutic predictive value of US-detected synovitis in inflammatory hand pain was examined in a large cohort. Finally the clinical utility of US at altering diagnosis and management in clinical rheumatology practice was prospectively examined. Results: For detection of knee synovitis, using arthroscopy as the gold-standard, US had higher sensitivity (98 vs 85%) and specificity (75 vs 25%) than clinical assessment. Kappa values for inter- and intra-reader reliability of US were 0.71 and 0.85 respectively. In the shoulder US-guided injections were 100% accurate, but 55% had evidence of extrabursal contrast limited to the tissue planes adjacent to the bursa. Outcome following hip injection was poor, but synovitis without osteophytes on US was the best predictor of short term benefit. In rheumatoid arthritis patients in clinical remission, the majority satisfying established remission criteria, US detected gray-scale and power Doppler (PD) synovitis in 85% and 60% patients respectively. The kappa value for inter-reader reliability was 0.60 for gray-scale, and intra-reader reliability was 0:60 for gray-scale and 0.62 for PD.Most inflammatory hand pain patients without clinical evidence of an inflammatory arthritis had US synovitis (55%); and US (p<O.OOl), but not clinical, synovitis was significantly associated with response to parenteral corticosteroid therapy. The site-specific diagnosis (53%) and management (53%) was altered in most patients referred for US in a routine clinic. Conclusion: Ultrasonography is now well validated in synovitis detection in small and large joints, and this has substantial implications for the accurate and early diagnosis of inflammatory arthritis, as well as in monitoring outcomes to therapy in rheumatoid arthritis. Ultrasonography can aid prognosis as well as improving placement of guided intra-articular therapies. This work has demonstrated that US has a significant role to play in rheumatology practice