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Software-Assisted Quantitative Measurement of Osteoarthritic Subchondral Bone Thickness
Published on: March 18, 2022
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Subchondral trabecular bone integrity changes following ACL injury and reconstruction: a cohort study with a nested,
C E Birch1, K S Mensch2, M J Desarno3
1University of Vermont, Department of Orthopaedics and Rehabilitation, San Antonio, TX, USA.
Osteoarthritis and Cartilage
|March 25, 2018
Summary
Anterior cruciate ligament (ACL) injury significantly alters tibial bone architecture, showing lower fractal dimensions (FD) in injured knees compared to healthy ones. This bone structure change persists even after ACL reconstruction and return to activity.
Area of Science:
- Orthopedics
- Biomedical Engineering
- Radiology
Background:
- Bone architecture changes after anterior cruciate ligament (ACL) injury are not well understood.
- Assessing tibial subchondral bone structure can provide insights into injury and healing.
- Fractal Dimension (FD) analysis offers a quantitative method to evaluate bone complexity.
Purpose of the Study:
- To investigate differences in tibial fractal signature between medial and lateral compartments in ACL-injured knees.
- To determine how these fractal signatures change after ACL reconstruction and return to activity.
- To establish side-to-side symmetry data for fractal dimensions in healthy controls.
Main Methods:
- Prospective cohort study with nested case-control analysis.
- Evaluated ACL-injured subjects and matched controls pre-surgery and at 46-month follow-up.
- Calculated serial Fractal Dimensions (FD) of tibial subchondral bone in medial and lateral compartments (horizontal and vertical dimensions).
Main Results:
- ACL-injured knees showed significantly different vertical FD signatures in both medial and lateral compartments compared to contralateral healthy tibias and controls at 46-month follow-up.
- Significant differences in horizontal FD profiles were observed in the lateral compartment of ACL-injured knees compared to controls and contralateral knees.
- No significant side-to-side differences in FD were found in healthy controls at any time point.
Conclusions:
- Tibial bone architecture, assessed by FD, is significantly altered in ACL-injured knees up to 46 months post-reconstruction.
- ACL injury leads to a generally lower fractal signature in the tibial subchondral bone.
- This study provides novel side-to-side symmetry data for medial and lateral FD in healthy individuals.
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