Journal of Osteoporosis and Physical Activity
Open Access

Abstract

Bone Remodeling Assessment in Patients with Renal Osteodystrophy Undergoing Vibrational Therapy: A MRI Finite Element Analysis Approach

Daniel C. Kargilis, Rashad Madi*, Alexandra S. Batzdorf, Sofia M. Miguez, Jonathan Guntin, Elizabeth A. Kobe, Felix W. Wehrli, Chamith S. Rajapakse

Introduction: Chronic Kidney Disease-Mineral and Bone Disorder (CKD-MBD) is a bone remodeling disorder resulting from impaired renal function. Patients with CKD have an increased risk of fractures, and current treatments offer limited effectiveness. Alternative interventions have been proven to be effective such as Low-Intensity Vibrational therapy (LIV) that triggers an anabolic bone response increasing the Bone Mineral Density (BMD) with no adverse effects. Our study aims to use MRI based finite element modeling to simulate bone strains in patients with Renal Osteo Dystrophy (ROD) at baseline and determine whether the results can help identify the relationship between the simulated strains and actual bone remodeling after Low-Intensity Vibration (LIV) therapy. By establishing this relationship, our study seeks to provide insight into the microarchitectural changes in bone that occur in response to LIV therapy, which could potentially lead to improved treatment strategies for ROD patients.

Materials and methods: The study utilized retrospective data from a randomized controlled trial, which assigned 30 patients with ROD equally to active and placebo groups and received daily 20 minutes treatment with LIV for 6 months. MRI scans of the patients’ distal tibias were conducted at baseline, and 6 months follow-up, and the resulting strain was calculated using Finite Element Analysis (FEA). The study also utilized baseline patient data to develop a multiple linear regression model to analyze the change in Bone Volume Fraction (BVF) over time.

Results: We found a positive correlation between baseline trabecular strain and percent change in trabecular BVF at 6 months follow-up (r=0.62, P=0.045) and between baseline trabecular strain and percent change in BVF in the center of the trabecular region (r=0.65, P=0.03). However, among placebo device users, there was a negative correlation between these variables in the right trabecular region (r=-0.76, P=0.02). Additionally, high-strain voxels experienced a gre ater percent change in BVF than low-strain voxels (P<0.0001).

Conclusion: This study discovered a link between initial trabecular strain and the efficacy of LIV therapy in patients diagnosed with ROD, suggesting that elevated baseline strain levels correspond with substantial alterations in BVF due to LIV. The study underlined the need to measure baseline trabecular strain instead of relying solely on initial BVF, demonstrating its pivotal role in treatment success. Further investigations into the relationship between these bone parameters would contribute to a better understanding and optimization of therapeutic approaches.

Published Date: 2025-01-27; Received Date: 2023-07-09