Aperture fixation with interference screws matching the diameter of the tunnel is associated with the risk of graft laceration and graft rotation. A hybrid fixation technique (extracortical and aperture fixation) with undersized interference screws provides a higher fixation strength when compared to an aperture fixation using only a screw matching the size of the tunnel and also reduces the risk of graft laceration. This research is an experimental laboratory study. We evaluated the initial fixation strength at time-zero of an extracortical-, a hybrid- and an aperture fixation in ACL reconstruction using extracortical buttons and different sized interference screws in porcine knees. The tests were performed using a single cycle and cyclic loading protocol. Analysis of yield load, maximum load and stiffness in the single cycle loading test showed no statistically significant differences for hybrid fixation with a 1 mm undersized screw and aperture fixation with a screw matching the size of the tunnel. Cyclic loading tests showed a statistically significant difference between hybrid and aperture fixation. The use of an undersized screw alone in aperture fixation resulted in insufficient fixation strength. The initial fixation strength of the hybrid technique with undersized screws is higher compared to an interference screw fixation alone. The hybrid fixation technique is an alternative for ACL graft fixation.
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http://dx.doi.org/10.1007/s00167-006-0159-x | DOI Listing |
BMB Rep
January 2025
Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang 37673; Division of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea.
Cryo-fixation techniques, including cryo-electron and cryofluorescence microscopy, enable the preservation of biological samples in a near-native state by rapidly freezing them into an amorphous ice phase. These methods prevent the structural distortions often caused by chemical fixation, allowing for high-resolution imaging. At low temperatures, fluorophores exhibit improved properties, such as extended fluorescence lifetimes, reduced photobleaching, and enhanced signal-tonoise ratios, making single-molecule imaging more accurate and insightful.
View Article and Find Full Text PDFSpine J
December 2024
Surgical and Orthopaedic Research Laboratories, Prince of Wales Clinical School, University of New South Wales, Sydney, New South Wales, Australia.
Background Context: 3D-printed titanium cage designs can incorporate complex, porous features for bone ingrowth and a greater surface area for minimizing subsidence. In a companion study (Part 1), we determined that increased surface area leads to decreased subsidence; however, it remains unclear how increasing the cage surface area, resulting in a smaller graft aperture, influences fusion.
Purpose: We evaluated the effects of surface area of 3D-printed titanium cages and the use of autologous bone grafts on spinal fusion in sheep.
Indian J Ophthalmol
October 2024
Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
Psychon Bull Rev
September 2024
School of Psychology, UNSW Sydney, Kensington, NSW, 2052, Australia.
Face recognition in humans is often cited as a model example of perceptual expertise that is characterized by an increased tendency to process faces as holistic percepts. However emerging evidence across different domains of expertise points to a critical role of feature-based processing strategies during the initial encoding of information. Here, we examined the eye-movement patterns of super-recognisers-individuals with extremely high face identification ability compared with the average person-using gaze-contingent "spotlight" apertures that restrict visual face information in real time around their point of fixation.
View Article and Find Full Text PDFPsychon Bull Rev
August 2024
Department of Psychology, Arizona State University, Tempe, AZ, USA.
A previously viewed scene is often remembered as containing a larger extent of the background than was actually present, and information that was likely present just outside the boundaries of that view is often incorporated into the representation of that scene. This has been referred to as boundary extension. Methodologies used in studies on boundary extension (terminology, stimulus presentation, response measures) are described.
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