@article{JordanHufnagelMcDonoghetal.2022, author = {Jordan, Martin C. and Hufnagel, Lukas and McDonogh, Miriam and Paul, Mila M. and Schmalzl, Jonas and Kupczyk, Eva and Jansen, Hendrik and Heilig, Philipp and Meffert, Rainer H. and Hoelscher-Doht, Stefanie}, title = {Surgical fixation of calcaneal beak fractures — biomechanical analysis of different osteosynthesis techniques}, series = {Frontiers in Bioengineering and Biotechnology}, volume = {10}, journal = {Frontiers in Bioengineering and Biotechnology}, issn = {2296-4185}, doi = {10.3389/fbioe.2022.896790}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-282792}, year = {2022}, abstract = {The calcaneal beak fracture is a rare avulsion fracture of the tuber calcanei characterized by a solid bony fragment at the Achilles tendon insertion. Treatment usually requires osteosynthesis. However, lack of biomechanical understanding of the ideal fixation technique persists. A beak fracture was simulated in synthetic bones and assigned to five different groups of fixation: A) 6.5-mm partial threaded cannulated screws, B) 4.0-mm partial threaded cannulated screws, C) 5.0-mm headless cannulated compression screws, D) 2.3-mm locking plate, and E) 2.8-mm locking plate. Different traction force levels were applied through an Achilles tendon surrogate in a material-testing machine on all stabilized synthetic bones. Outcome measures were peak-to-peak displacement, total displacement, plastic deformation, stiffness, visual-fracture-line displacement, and mode of implant failure. The 2.3- and 2.8-mm plating groups showed a high drop-out rate at 100 N tension force and failed under higher tension levels of 200 N. The fracture fixation using 4.0-mm partial threaded screws showed a significantly higher repair strength and was able to withhold cyclic loading up to 300 N. The lowest peak-to-peak displacement and the highest load-to-failure and stiffness were provided by fracture fixation using 6.5-mm partial threaded cannulated screws or 5.0-mm headless cannulated compression screws. As anticipated, large 6.5-mm screw diameters provide the best biomechanical fixation. Surprisingly, the 5.0-mm headless cannulated compression screws yield reliable stability despite the absent screw head and washer. When such large screws cannot be applied, 4.0-mm screws also allow reasonable fixation strength. Plate fixation should be implemented with precaution and in combination with a restrictive postoperative motion protocol. Finally, clinical cases about the surgical application and recovery are included.}, language = {en} } @article{SzymskiAchenbachSiebentrittetal.2021, author = {Szymski, Dominik and Achenbach, Leonard and Siebentritt, Martin and Simoni, Karola and Kuner, Norbert and Pfeifer, Christian and Krutsch, Werner and Alt, Volker and Meffert, Rainer and Fehske, Kai}, title = {Injury epidemiology of 626 athletes in surfing, wind surfing and kite surfing}, series = {Open Access Journal of Sports Medicine}, volume = {12}, journal = {Open Access Journal of Sports Medicine}, doi = {10.2147/OAJSM.S316642}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-261545}, pages = {99-107}, year = {2021}, abstract = {Introduction/Background Surfing, wind surfing and kite surfing enjoy a growing popularity with a large number of athletes worldwide. The aim of this study was to identify and compare the injury profiles and compare the injury profiles of these three extreme water sports. Materials and Methods These data for this retrospective cohort study were collected through an online standardised questionnaire during the 2017-18 season. The questionnaire included questions about anthropometry, skill level, injury diagnosis, injury mechanism, environmental conditions and training regimes. Results The 626 athletes included reported 2584 injuries. On average, each athlete sustained 4.12 injuries during the season. The most frequent injury location was in the lower extremity, in particular the foot, with 49 (16.4\%) injuries in surfing, 344 (18.3\%) in wind surfing and 79 (19.7\%) in kite surfing. Surfing demonstrated a particularly high rate of head injuries (n = 37; 12.4\%). Other frequent injury types were skin lesions (up to 42.1\%) and contusions (up to 40.5\%). The most common injury across all surfing sports was skin lesions of the foot (wind surfing: 11.7\%; kite surfing: 13.2\%; surfing: 12.7\%). In surfing, skin lesions of the head were frequently observed (n = 24; 8.0\%). In surfing, a 'too large wave' (n = 18; 24.7\%) was main cause of the injury, while in wind surfing (n = 189; 34.5\%) and kite surfing (n = 65; 36.7\%) 'own incompetence' led to the most injuries. Conclusion This unique study compares injury epidemiology and mechanism in the three most popular surfing sports: wind surfing, kite surfing and surfing. Overall, injuries were sustained mainly in the lower extremity, while surfing also demonstrated a high rate of head injuries.}, language = {en} }