Article
Orthopedics
G-Yves Laflamme, Philippe Moisan, Julien Chapleau, Julien Goulet, Stephane Leduc, Benoit Benoit, Dominique M. Rouleau
Summary: This study investigates novel technical factors associated with mechanical failures and complications in proximal humerus fracture fixation. The importance of reduction and calcar support in PHF fixation is critical, with attention needed to avoid varus reduction, maximize medial support, avoid screws longer than 45 mm in the proximal rows, and restore the humeral offset within 6 mm or less.
JOURNAL OF ORTHOPAEDIC TRAUMA
(2021)
Article
Orthopedics
Jana Felicitas Schader, Dominic Mischler, Jan Dauwe, R. Geoff Richards, Boyko Gueorguiev, Peter Varga
Summary: Subject-specific optimization of screw orientations in a fixed-angle locking plate can reduce the predicted cutout failure risk in unstable 3-part proximal humerus fractures. The optimized screw orientations significantly decreased bone strain around the screws compared to cohort-specific and original orientations, with greater benefits observed in female patients.
JOURNAL OF SHOULDER AND ELBOW SURGERY
(2022)
Article
Chemistry, Multidisciplinary
Angel D. Castro-Franco, Ismael Mendoza-Munoz, Alvaro Gonzalez-Angeles, Mildrend I. Montoya-Reyes, Nun Pitalua-Diaz
Summary: This study aimed to determine the optimal screw insertion angle configuration for a two-part proximal humerus fracture-locking plate osteosynthesis treatment using finite element analysis. The results showed that the optimal screw insertion angle configuration improved the interfragmentary strain value of the fracture, with calcar screws being the most significant feature in fracture stability.
APPLIED SCIENCES-BASEL
(2022)
Article
Engineering, Biomedical
Vasiliki C. Panagiotopoulou, Marzieh Ovesy, Boyko Gueorguiev, R. Geoff Richards, Philippe Zysset, Peter Varga
Summary: This study aimed to develop an experimental model for single screw perforation in human humeral head and evaluate the ability of densitometric measures and micro finite element analyses to predict this failure event. Results showed that nonlinear microFE models had the strongest predictive capability for perforation force and displacement.
JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS
(2021)
Article
Biotechnology & Applied Microbiology
Zhengguo Zhu, Zuhao Chang, Wei Zhang, Hongzhe Qi, Hao Guo, JiaQi Li, Lin Qi, Shaobo Nie, Peifu Tang, Yonghui Liang, Xing Wei, Hua Chen
Summary: This study compared the intra- and extramedullary assembly fixation with traditional fixation methods in osteoporotic proximal humeral fractures. The results showed that the intra- and extramedullary assembly fixation group performed better in terms of initial stiffness and number of cycles loaded to failure, with smaller relative displacement values.
FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY
(2023)
Article
Orthopedics
Dane J. Brodke, Ajay Gurbani, Christopher Lee
Summary: The surgical treatment of proximal humerus fractures is commonly associated with high complication rates. However, innovations in technique and implant design are improving the success rates and mitigating some failures.
JOURNAL OF THE AMERICAN ACADEMY OF ORTHOPAEDIC SURGEONS
(2023)
Article
Orthopedics
Antoine Dewarrat, Alexandre Terrier, Bardia Barimani, Frederic Vauclair
Summary: This study compared the clinical outcomes and complications of two surgical techniques for proximal humeral fracture. It found that patients treated with ALPS system had better shoulder range of motion and lower complication rates.
BMC MUSCULOSKELETAL DISORDERS
(2023)
Review
Biology
Lorenzo Massimo Oldrini, Pietro Feltri, Jacopo Albanese, Francesco Marbach, Giuseppe Filardo, Christian Candrian
Summary: This study aimed to quantify complications and reintervention rates in patients treated with PHILOS plate for proximal humerus fractures. The findings showed higher complication rates in patients over 55 years old, with screw cut-out being the most common complication.
Article
Orthopedics
Hyungsuk Kim, Yang-Guk Chung, Ji Seok Jang, Yongdeok Kim, Soo Bin Park, Hyun Seok Song
Summary: The study compared the angles between the humerus and plate, finding that the lateral angle of the humerus was larger than the plates, making it prone to varus reduction and medial collapse.
ARCHIVES OF ORTHOPAEDIC AND TRAUMA SURGERY
(2022)
Article
Engineering, Biomedical
Zhengguo Zhu, Zuhao Chang, Wei Zhang, Shaobo Nie, Lin Qi, Peifu Tang, Hua Chen, Yujie Liu
Summary: This study aimed to compare the biomechanical properties of different lengths of fibula with or without calcar screw in osteoporotic proximal humeral fracture. The results showed that the groups with a 12-cm fibular strut had significant improvement in terms of initial stiffness, number of cycles loaded to failure, and relative displacement values compared to the groups with a 6-cm fibular strut, regardless of calcar screw implementation. Furthermore, the groups with calcar screws also demonstrated promising biomechanical stability irrespective of fibular length. Therefore, the use of lateral locking plate with longer endosteal fibular augmentation and calcar screw can significantly improve biomechanical stability for elderly proximal humeral fractures with posteromedial comminution.
CLINICAL BIOMECHANICS
(2023)
Article
Medicine, General & Internal
Rony-Orijit Dey Hazra, Johanna Illner, Karol Szewczyk, Mara Warnhoff, Alexander Ellwein, Robert Maximillian Blach, Helmut Lill, Gunnar Jensen
Summary: This study aimed to investigate whether age predicts the functional outcome of locking plate osteosynthesis for proximal humeral fractures. The results showed comparable functional outcomes and complication rates in both age groups, suggesting that treatment decisions should be based on fracture morphology and individual patient factors.
JOURNAL OF CLINICAL MEDICINE
(2022)
Article
Geriatrics & Gerontology
Hyojune Kim, Myung Jin Shin, Erica Kholinne, Janghyeon Seo, Duckwoo Ahn, Ji Wan Kim, Kyoung Hwan Koh
Summary: This biomechanical study found that using at least 7 proximal screws for stable fixation of a 2-part proximal humerus fracture with a locking plate can result in better stability and minimize the risk of secondary varus collapse or fixation failure.
GERIATRIC ORTHOPAEDIC SURGERY & REHABILITATION
(2021)
Article
Orthopedics
Shan Fan, Mingming Yin, Yibo Xu, Cheng Ren, Teng Ma, Yao Lu, Ming Li, Zhong Li, Kun Zhang
Summary: This study aimed to investigate the clinical efficacy of locking compression plate fixation for femoral intertrochanteric fractures in patients with preexisting proximal femoral deformity. The results showed that locking compression plate fixation is a simple and effective treatment method, with improved hip function and quality of life in patients during postoperative follow-up.
JOURNAL OF ORTHOPAEDIC SURGERY AND RESEARCH
(2021)
Article
Orthopedics
Konrad Schuetze, S. Ehinger, A. Eickhoff, C. Dehner, F. Gebhard, P. H. Richter
Summary: The study demonstrates that cement augmentation of the proximal femur nail blade is a safe procedure, which does not increase postoperative complications or mortality.
ARCHIVES OF ORTHOPAEDIC AND TRAUMA SURGERY
(2021)
Article
Biophysics
An Sermon, Ivan Zderic, Roberto Khatchadourian, Simon Scherrer, Matthias Knobe, Karl Stoffel, Boyko Gueorguiev
Summary: This study analyzed the biomechanical impact of bone cement augmentation on PFNA and TFNA head elements in a human cadaveric model with poor bone quality. The results showed that all types of implants demonstrated higher fixation strength and cut-out resistance after augmentation, with TFNA blades showing the highest values. Bone cement augmentation significantly increases the cut-out resistance of instrumented TFNA and PFNA head elements, making it a valid supplementary treatment option for poor bone quality.
JOURNAL OF BIOMECHANICS
(2021)
Article
Critical Care Medicine
Simon Lambert, Dominic Mischler, Markus Windolf, Pietro Regazzoni, Alberto Fernandez Dell'Oca, Boyko Gueorguiev, Peter Varga
Summary: Stephan Perren's significant contributions in bone pathobiology, healing, and fracture fixation have left a lasting impact on clinical care, while his important role in disseminating and applying these principles through technology in the learning environment is also noteworthy. He played a key role in developing methods and tools to translate principles of bone mechano-pathobiology into the practical world of clinical musculoskeletal traumatology through active learning environments.
INJURY-INTERNATIONAL JOURNAL OF THE CARE OF THE INJURED
(2021)
Article
Critical Care Medicine
Markus Windolf, Manuela Ernst, Ronald Schwyn, Daniel Arens, Stephan Zeiter
Summary: The study found that early fracture activity, defined as the number of stimulatory events per time, had a positive effect on bone healing. There were strong correlations between fracture activity in the first and second weeks post-operation and the torsional strength of the healed bone, as well as the maximum callus area measured from X-rays. However, the role of fracture activity in the later timepoints was not significant. The findings suggest the importance of mechanical environment in the direct post-operative healing phase and may advocate for direct post-operative weight bearing, pending further clinical validation.
INJURY-INTERNATIONAL JOURNAL OF THE CARE OF THE INJURED
(2021)
Article
Orthopedics
Jana Felicitas Schader, Dominic Mischler, Jan Dauwe, R. Geoff Richards, Boyko Gueorguiev, Peter Varga
Summary: Subject-specific optimization of screw orientations in a fixed-angle locking plate can reduce the predicted cutout failure risk in unstable 3-part proximal humerus fractures. The optimized screw orientations significantly decreased bone strain around the screws compared to cohort-specific and original orientations, with greater benefits observed in female patients.
JOURNAL OF SHOULDER AND ELBOW SURGERY
(2022)
Article
Engineering, Biomedical
Marzieh Ovesy, Juan Diego Silva-Henao, James W. A. Fletcher, Boyko Gueorguiev, Philippe K. Zysset, Peter Varga
Summary: This study compared different methods in predicting the pullout force of 3.5 mm screws in human cadaveric tibial cortical bone, with results showing that the non-linear micro-FE models were more accurate in predicting the experimental outcomes.
JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS
(2022)
Article
Orthopedics
F. Souleiman, I Zderic, T. Pastor, P. Varga, T. Helfen, G. Richards, B. Gueorguiev, J. Theopold, G. Osterhoff, P. Hepp
Summary: This study biomechanically investigated the effect of cartilage loss on shoulder stability in different dislocation directions. The results showed that cartilage loss significantly decreased shoulder stability, with the greatest effect observed in the anterior-inferior dislocation directions. This suggests that surgical interventions to restore cartilage should be considered for recurrent shoulder dislocations.
KNEE SURGERY SPORTS TRAUMATOLOGY ARTHROSCOPY
(2022)
Article
Engineering, Biomedical
Denis Schenk, Michael Indermaur, Mathieu Simon, Benjamin Voumard, Peter Varga, Michael Pretterklieber, Kurt Lippuner, Philippe Zysset
Summary: The study refined and experimentally validated a homogenized finite element method for in vivo prediction of bone strength and stiffness at the distal segments of the radius and the tibia using a unified set of material properties. The identified material properties allowed for accurate prediction of stiffness and failure load, demonstrating excellent agreement with experimental results at both measurement sites.
JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS
(2022)
Article
Biotechnology & Applied Microbiology
Michiel Herteleer, Armin Runer, Magdalena Remppis, Jonas Brouwers, Friedemann Schneider, Vasiliki C. Panagiotopoulou, Bernd Grimm, Clemens Hengg, Rohit Arora, Stefaan Nijs, Peter Varga
Summary: Postoperative shoulder activity after proximal humerus fracture treatment may depend on the rehabilitation protocol. This study evaluated continuous shoulder activity monitoring in elderly patients with complex fractures, comparing two rehabilitation protocols. The results showed that shoulder angles and elevation events changed over time, but there were no significant differences between the two centers.
BIOENGINEERING-BASEL
(2023)
Article
Medicine, General & Internal
Biser Makelov, Dominic Mischler, Peter Varga, Theerachai Apivatthakakul, James W. A. Fletcher, Deyan Veselinov, Till Berk, Dimitur Raykov, Boyko Gueorguiev
Summary: This prospective clinical study aimed to investigate and evaluate the clinical and functional outcomes of single-stage externalized locked plating for unstable proximal and distal meta-diaphyseal tibial fractures. The results showed that this treatment method provided adequate stability of fixation with good clinical outcomes and no complications.
JOURNAL OF CLINICAL MEDICINE
(2023)
Article
Medicine, General & Internal
Markus Windolf, Dominik Knierzinger, Stefaan Nijs, An Sermon, Michael Blauth, Robert Geoff Richards, Jan Buschbaum
Summary: This study investigated the performance of a novel implant positioning technology (Xin1) for proximal humerus fractures in both laboratory and clinical settings. The results showed that the Xin1 system significantly improved surgical precision, procedure time, and reduced radiation exposure. Retrospective analysis on clinical patients demonstrated good performance of the system in real-life fracture situations, but further validation is needed before clinical implementation.
MEDICINA-LITHUANIA
(2023)
Article
Medicine, General & Internal
Karen Mys, Luke Visscher, Kenneth Petrus van Knegsel, Dominic Gehweiler, Torsten Pastor, Amirsiavosh Bashardoust, Anna Sophie Knill, Carolin Danker, Jan Dauwe, Rayna Mechkarska, Georgi Raykov, Grzegorz Marek Karwacki, Matthias Knobe, Boyko Gueorguiev, Markus Windolf, Simon Lambert, Stefaan Nijs, Peter Varga
Summary: This study aimed to develop a 3D segmentation fracture mapping technique to describe the spatial pattern and cortical bone loss in complex proximal humerus fractures (PHFs). The results showed that the fracture lines mainly passed through the surgical neck and between the tuberosities and tendon insertions. This information is important for future studies on surgical training and implant design.
MEDICINA-LITHUANIA
(2023)
Article
Medicine, General & Internal
Daniel Zhelev, Stoyan Hristov, Ivan Zderic, Stoyan Ivanov, Luke Visscher, Asen Baltov, Simeon Ribagin, Karl Stoffel, Franz Kralinger, Joerg Winkler, R. Geoff Richards, Peter Varga, Boyko Gueorguiev
Summary: This study confirmed that the new technique of using polymethylmethacrylate bone cement augmentation can significantly enhance fixation stability and reduce the risk of postoperative complications in the treatment of unstable proximal humerus fractures.
MEDICINA-LITHUANIA
(2023)
Article
Medicine, General & Internal
Markus Windolf, Maximilian Heumann, Viktor Varjas, Caroline Constant, Manuela Ernst, Robert Geoff Richards, Hans-Joachim Wilke, Lorin Michael Benneker
Summary: Spinal fusion is a widely used intervention with complications. Current diagnostic methods are limited, but a new implantable sensor system has the potential to overcome these limitations. However, its application in spinal fusion has not been demonstrated yet.
MEDICINA-LITHUANIA
(2022)
Article
Medicine, General & Internal
Markus Windolf, Viktor Varjas, Dominic Gehweiler, Ronald Schwyn, Daniel Arens, Caroline Constant, Stephan Zeiter, Robert Geoff Richards, Manuela Ernst
Summary: The study aims to investigate the safety and performance of the Fracture Monitor device in animal models and explore the application of continuous implant load monitoring in assessing fracture healing. The results show that the sensor system can autonomously function for a certain period of time without any adverse effects. The relative implant loads at 4 and 8 weeks post-operation are significantly correlated with radiographic scores and normalized bone volume metrics.
MEDICINA-LITHUANIA
(2022)
Article
Medicine, General & Internal
Torsten Pastor, Tatjana Pastor, Philipp Kastner, Firas Souleiman, Matthias Knobe, Boyko Gueorguiev, Markus Windolf, Jan Buschbaum
Summary: The study evaluated the digitally enhanced hands-on surgical training concept and device for distal interlocking of intramedullary nails, showing high scores in training capability and realism. Construct validity was proven by reliably discriminating between experts and novices, with participants indicating high further training potential for the device.
MEDICINA-LITHUANIA
(2022)