Background: Experimental analyses have demonstrated the impact of mechanical conditions on bone healing. In critical clinical cases the mechanical conditions may be even more demanding than those in experimental studies. This study set out to examine the gap movements in distraction and correction osteotomies and to determine the suitability of initial fixation.
Patients And Methods: Interfragmentary movements, ground reaction forces, and stability (ground reaction force divided by interfragmentary movement) were measured in 18 patients with tibial osteotomies stabilized by Ilizarov hybrid constructs until either bone union or conversion to internal fixation occurred (9 distraction treatments, 9 correction osteotomies). Consolidation was determined by clinical evaluation and standard radiographic techniques.
Results: In both groups cocontraction led to gap movements comparable to level walking. Although the in vitro stiffness was slightly increased in the correction constructs, the interfragmentary movement in vivo was initially comparable between the groups. Patients undergoing distraction returned later to full weight bearing than patients undergoing correction treatment. In the correction group the stability increased with treatment time, while in the distraction group the stability remained relatively small.
Conclusions: The in vivo mechanical conditions in challenging clinical cases appear far more demanding than those in experimental studies. In distraction, mechanical conditions at the defect appear to be more critical than during correction osteosynthesis. According to the persistence of shear motion, even after 80 days of treatment, it may from the clinical point of view be important to maintain interfragmentary compression during the whole healing process and thereby reduce shear.
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http://dx.doi.org/10.1007/s00423-002-0340-8 | DOI Listing |
PLoS One
January 2025
Department of Agricultural Engineering, Technical and Vocational University, Tehran, Iran.
With the growing need for sustainable transportation solutions, understanding the relationship between driving characteristic parameters, vehicle type, and their impact on emissions and fuel consumption over real driving scenarios is becoming increasingly important. In this paper, four conventional vehicles and one hybrid vehicle with different technologies were compared in four distinct routes in Tehran city. Nineteen real driving cycles were generated using widely employed K-means and PCA algorithms.
View Article and Find Full Text PDFPLoS One
January 2025
Key Laboratory of Clinical Evaluation Technology for Medical Device of Zhejiang Province, Department of Clinical Engineering and Material Supplies, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, P.R. China.
The structural alterations in the constituent materials of nanocomposites such as graphene nanocomposites typically induce changes in their properties including mechanical, electrical, and optical properties. Therefore, by altering the preparation conditions of nanocomposites and investigating their responsiveness to basic biomolecules (such as proteins), it is possible to explore the application potentials of the composites and guide development of new nanocomposite preparation. In this study, different composites of graphene oxide and gold nanoparticles (AuNPs/GO) were obtained by varying the volumes of reducing agents used in the one-pot hydrothermal method.
View Article and Find Full Text PDFJ Bone Miner Res
January 2025
Army Health and Performance Research, Army Headquarters, Andover, United Kingdom.
Calcium supplementation before exercise attenuates the decrease in serum calcium and increase in PTH and bone resorption. This study investigated the effect of calcium supplementation on calcium and bone metabolism during load carriage in women. Forty-eight women completed two load carriage sessions (load carriage 1 n = 48; load carriage 2 n = 40) (12.
View Article and Find Full Text PDFSICOT J
January 2025
Department of Orthopaedic Surgery, Joint Replacement Unit, Kuala Lumpur Hospital, Ministry of Health Malaysia, Jalan Pahang, 50586 Kuala Lumpur, Malaysia.
Introduction: Extraarticular deformity (EAD) with knee arthritis is a complex condition involving tri-planar bone deformity with pathological malalignment and chronic soft tissue contracture or laxity in the knee joint. Intraarticular correction by TKA, which was previously performed with conventional manual jig by mechanical alignment technique, had its limits and difficulties especially extensive soft tissue release and risk of jeopardizing the collateral ligaments. Robotic technology allows for reproducible and precise execution of surgical plan and allows adjustment to various new personalised alignment philosophy including functional alignment (FA).
View Article and Find Full Text PDFNano Lett
January 2025
Interdisciplinary Graduate Program in Materials Science, Vanderbilt University, Nashville, Tennessee 37235, United States.
Permeance-selectivity trade-offs are inherent to polymeric membranes. In fuel cells, thinner proton exchange membranes (PEMs) could enable higher proton conductance and increased power density with lower area-specific resistance (ASR), smaller ohmic losses, and lower ionomer cost. However, reducing thickness is accompanied by an increase in undesired species crossover harming performance and long-term efficiency.
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