Dual energy CT for more accurate diagnosis and monitoring of early osteoarthritis-related shoulder injuries

Abstract

The rapid acceleration of population aging has led to a growing prevalence of age-related musculoskeletal (MSK) conditions, such as osteoarthritis (OA). Dual-energy computed tomography (DECT) is an advanced imaging modality that shows promise in enhancing the diagnosis and characterization of MSK disorders by providing improved visualization of joint and tissue changes after injury. These advancements may support more effective treatment planning and better patient outcomes. The primary aim of this study was to refine input parameters used in DECT imaging and apply them to better understand the relationship between shoulder injury and early osteoarthritic changes over a six month period. This knowledge is expected to improve therapeutic outcomes and support early screening for individuals at high risk of developing OA. DECT was employed to quantify volumetric bone mineral density (vBMD) and to model bone stiffness and loading using finite element modeling (FEM) in both cadaveric specimens and participants. Three anatomical regions of the proximal humerus were assessed: the humeral shaft diaphysis, the articular surface of the humerus (humeral head), and the anatomical neck. Cadaveric scans were performed using both dipotassium phosphate (K2HPO4) and hydroxyapatite (HA) calibration phantoms while participants were scanned using only the HA phantom. Imaging was conducted using both BONE and Standard (STD) reconstruction kernels at three energy pair combinations: 40/90, 90/140, and 40/140 keV. These combinations were chosen to evaluate whether higher energy pairs could help mitigate attenuation issues commonly encountered at lower energy pair combinations. The BONE kernel was selected for its superior bone edge sharpening and contrast, whereas the STD kernel was used to enhance visualization of surrounding soft tissues. Participant imaging occurred at baseline (within six weeks of injury) and again at six-month follow-up. Results of this study demonstrated that both vBMD and FEM-derived stiffness values were significantly higher in the diaphysis when scanned using the BONE kernel at the highest energy pair combination (90/140 keV). In contrast, the anatomical neck consistently showed the lowest vBMD and stiffness values, with no significant differences in vBMD or FEM-derived stiffness values observed within the anatomical neck or humeral head regions under the same parameters. By developing patient-specific, image-based computational models, this study contributes to a deeper understanding of both biomechanical and imaging characteristics of early shoulder OA, potentially informing future diagnostic and therapeutic strategies.