Objective: Beyond static assessment, functional techniques are increasingly applied in magnetic resonance imaging (MRI) studies. Stress MRI techniques bring together MRI and mechanical loading to study knee joint and tissue functionality, yet prototypical axial compressive loading devices are bulky and complex to operate. This study aimed to design and validate an MRI-compatible pressure-controlled varus-valgus loading device that applies loading along the joint line.
Methods: Following the device's thorough validation, we demonstrated proof of concept by subjecting a structurally intact human cadaveric knee joint to serial imaging in unloaded and loaded configurations, i.e. to varus and valgus loading at 7.5 kPa (= 73.5 N), 15 kPa (= 147.1 N), and 22.5 kPa (= 220.6 N). Following clinical standard (PDw fs) and high-resolution 3D water-selective cartilage (WATSc) sequences, we performed manual segmentations and computations of morphometric cartilage measures. We used CT and radiography (to quantify joint space widths) and histology and biomechanics (to assess tissue quality) as references.
Results: We found (sub)regional decreases in cartilage volume, thickness, and mean joint space widths reflective of areal pressurization of the medial and lateral femorotibial compartments.
Discussion: Once substantiated by larger sample sizes, varus-valgus loading may provide a powerful alternative stress MRI technique.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8302563 | PMC |
| http://dx.doi.org/10.1007/s10334-020-00844-6 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Benefits of Using Functional Joint Coordinate Systems in In Vitro Knee Testing.
J Biomech Eng
January 2025
Department of Biomedical Engineering and Lerner Research Institute, Cleveland Clinic, 2111 E. 96th Street, Cleveland, OH 44106.
To measure knee joint kinematics, coordinate systems (CS) must be assigned to the tibia and femur. Functional CS have been shown to be more reproducible than Anatomical. This study aims to quantify the benefits of using Functional CS in in vitro testing.
View Article and Find Full Text PDFArthroscopic Assisted Reduction and Fixation in Tibial Plateau Fractures: A Prospective Review.
J Orthop Case Rep
December 2024
Department of Orthopaedics, Dr. D.Y. Patil Medical College Hospital and Research Institute, Pimpri-Chinchwad, Maharashtra, India.
Introduction: Tibial plateau fractures, which constitute approximately 1% of all fractures with an incidence of 10.3/100,000 annually, result from varus or valgus forces combined with axial loading in the knee. These fractures display a bimodal distribution, affecting younger individuals through high-velocity trauma and older individuals through low-energy trauma.
View Article and Find Full Text PDFOptimal biomechanical choice of implant placement in various pilon fracture types: a finite element study.
BMC Musculoskelet Disord
November 2024
Department of Orthopedics, General Hospital of Central Theater Command of PLA, (Wuhan General Hospital of Guangzhou Command, Previously), Hubei Province, NO. 627, Wuluo Road, Wuhan, 430030, P.R. China.
Article Synopsis
- The study examines the impact of fracture displacement directions on stress distribution in both bones and implants for pilon fractures, a type of ankle injury.
- Different fracture types were categorized and assessed under specific loading conditions, utilizing various plate placements and lag screws for treatment.
- Results indicated significant differences in stress levels among the different fracture subtypes, leading to recommendations for optimal implant placement based on fracture type to improve surgical outcomes.
45° helical plates are a valid alternative to straight plates for treatment of proximal humeral shaft fractures.
J Orthop Res
November 2024
Department of Orthopaedic and Trauma Surgery, Lucerne Cantonal Hospital, Lucerne, Switzerland.
Helical plates used for proximal humeral shaft fracture fixation avoid the radial nerve distally as compared to straight plates. To investigate in a human cadaveric model the biomechanical competence of straight lateral plates versus 45° helical plates used for fixation of proximal comminuted humeral shaft fractures, eight pairs of human cadaveric humeri were instrumented using either a long straight PHILOS plate (Group 1) or a 45° helical plate (Group 2) for treatment of an unstable proximal humeral shaft fracture. All specimens were tested under non-destructive quasi-static loading in axial compression, internal and external rotation, and bending in four directions.
View Article and Find Full Text PDFCompressive force and valgus torque are the predominant applied loads during the pivot shift exam: An in vitro study.
Knee Surg Sports Traumatol Arthrosc
November 2024
Sports Medicine Institute, Hospital for Special Surgery, New York, New York, USA.
Purpose: Despite the clinical utility of the pivot shift exam, the requisite applied forces and torques to elicit a pivot shift remain unclear. The purposes of this study are (1) to identify the greatest forces and torques applied to the knee during the pivot shift exam and (2) to evaluate if the applied loads differ among experienced surgeons.
Methods: Three cadaveric hemipelvis-to-toe specimens (ages 53, 36 and 31 years; two males and one female) with no history of knee or hip injury were utilized.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!