Citations

Abstract Background Computational modeling is a tool being deployed for orthopaedic solutions but its use in the hand and wrist remains limited. This work used a model to simulate a clinically relevant provocative scaphoid shift maneuver (SSM) with different levels of scapholunate interosseous ligament (SLIL) injuries to observe the effect on different metrics. Methods A personalized model simulated the full SSM motion cycle from ulnar deviation with extension to radial deviation with flexion informed by the participant’s motion obtained from dynamic computed tomography. Models repeated the SSM under different levels of SLIL injury and reported changes in joint kinematics, contact mechanics, and ligament forces. Results The fully injured model increased scaphoid dorsal translation, flexion, and radial deviation compared to the intact condition and caused a subluxation of the scaphoid. Radioscaphoid contact areas were approximately 200% greater in the fully injured model compared with all others and the fully injured model was the only condition where contact force decreased across the motion cycle. Ligament forces in the intact condition were on average 33.0 N and 54.2 N for the volar and dorsal SLIL, respectively. Lastly, the long radiolunate, an extrinsic stabilizer, had forces that increased following SLIL injury. Conclusions Computational models can successfully recreate clinically observed behaviors of an SSM, including scaphoid subluxation, while providing new insights via quantification of contact mechanics and ligament forces. Contact mechanics metrics may be important for understanding the long-term progression of untreated SLIL injuries to osteoarthritis. Additionally, ligament force metrics may explain the progression of SLIL injuries from volar SLIL to dorsal SLIL and highlight the importance of repairing extrinsic stabilizers of the joint, due to increased force sharing following SLIL injury. This work provides a pathway to future studies investigating the effects of SLIL injury and repair, both acutely and chronically.

ABSTRACT Background Prolonged QT interval is common in end‐stage renal disease (ESRD) on dialysis, but its long‐term cardiovascular (CV) implications remain unclear. Methods Using TriNetX network (2010–2024), we identified adults with ESRD on dialysis and categorized them by QTc status. After 1:1 propensity score matching ( n = 3428/group), outcomes (hazard ratio [HR]) were assessed using Cox regression. Results Prolonged QTc (> 500 ms) was associated with higher risk of all‐cause mortality (HR 1.67; p < 0.001), MACEs (HR 1.40; p < 0.001), cardiac arrest (HR 1.75; p < 0.001), sustained ventricular arrhythmia (HR 1.66; p < 0.001), new‐onset atrial fibrillation (HR 1.12; p = 0.01), and acute myocardial infarction (HR 2.19; p < 0.001). Conclusions In ESRD patients on dialysis, prolonged QT interval was independently associated with adverse CV outcomes and mortality.

ABSTRACT The paraneurium is a distinct connective tissue sheath that loosely envelopes the epineurium. The space between the para‐ and epineurium (the subparaneurial compartment) holds significant clinical relevance, serving as a target for deposition of regional anesthesia and a potential pathway for the pathological spread of cysts and tumors. However, visualization of the paraneurial layer, as a separate structure from the epineurium, remains challenging with conventional MRI, especially in the absence of pathology. This study evaluated the visualization of the paraneurium using ultra‐high‐field 7‐Tesla (7 T) MRI compared to conventional field strengths. We assessed normal nerve anatomy and a spectrum of pathological cases, including intraneural ganglion cysts, schwannomas, intraneural perineuriomas, and metastatic melanoma. The results demonstrated that 7 T MRI provides superior resolution and delineation of the paraneurium compared to 1.5 and 3 T systems. In normal anatomy, T1‐weighted and proton density (PD) sequences provided optimal contrast between the paraneurium and surrounding adipose tissue. In contrast, for pathological cases, T2‐weighted sequences with fat suppression were superior for depicting the paraneurium and identifying subparaneurial involvement. In conclusion, 7 T MRI offers a significant advantage in identifying the thin paraneurial layer. This capability provides valuable insights into the pathogenesis of tumor spread and holds promise for improving pre‐operative planning and clinical decision‐making in peripheral nerve pathology.

ABSTRACT Purpose Active lesion expansion is clinically important because it can indicate disease progression and influence management and treatment planning. However, sequential imaging is often unavailable, and rapid growth can only be inferred from indirect findings such as active perilesional tissue injury. This study aimed to implement and test the feasibility of an MR elastography (MRE)‐based technique for assessing the expansile nature of mass lesions by detecting stiffness changes caused by mechanical strain manifestations in adjacent tissues. Methods A tissue strain mapping (TSM) algorithm was developed using spatial–temporal directional filtering to reveal the presence of perilesional latent strain that is not apparent in conventional MRE inversions. The technical feasibility was tested in tissue‐simulating phantoms containing a mass that was progressively expanded. Preliminary feasibility for clinical application was also demonstrated in representative in vivo examples. Resulting TSM maps were compared with conventional MRE stiffness maps. Results In the phantom experiments, TSM revealed the presence of local strain at the periphery of the expanding mass, with the effect increasing proportionally to the degree of expansion. Conventional MRE did not demonstrate comparable localized stiffening patterns. In vivo examples showed similar perilesional strain features that were not apparent on conventional MRE maps. Conclusion The feasibility of the proposed MRE‐based TSM technique was demonstrated in phantom and preliminary in vivo studies. These findings suggest that the technique is a promising tool for assessing the expansile nature of mass lesions and motivate further development of the TSM processing and exploration of potential clinical applications.