@article{JordanHoelscherDohtFehskeetal.2015,
  author    = {Jordan, Martin C. and Hoelscher-Doht, Stefanie and Fehske, Kai and Gilbert, Fabian and Jansen, Hendrik and Meffert, Rainer H.},
  title     = {Bunnell or cross-lock Bunnell suture for tendon repair? Defining the biomechanical role of suture pretension},
  series = {Journal of Orthopaedic Surgery and Research},
  volume    = {10},
  journal   = {Journal of Orthopaedic Surgery and Research},
  number    = {192},
  doi       = {10.1186/s13018-015-0331-4},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-126262},
  year      = {2015},
  abstract  = {Background Suture pretension during tendon repair is supposed to increase the resistance to gap formation. However, its effects on the Bunnell suture technique are unknown. The purpose of this study was to determine the biomechanical effects of suture pretension on the Bunnell and cross-lock Bunnell techniques for tendon repair. Methods Eighty porcine hindlimb tendons were randomly assigned to four different tendon repair groups: those repaired with or without suture pretension using either a simple Bunnell or cross-lock Bunnell technique. Pretension was applied as a 10 \% shortening of the sutured tendon. After measuring the cross-sectional diameter at the repair site, static and cyclic biomechanical tests were conducted to evaluate the initial and 5-mm gap formation forces, elongation during cyclic loading, maximum tensile strength, and mode of failure. The suture failure mechanism was also separately assessed fluoroscopically in two tendons that were repaired with steel wire. Results Suture pretension was accompanied by a 10 to 15 \% increase in the tendon diameter at the repair site. Therefore, suture pretension with the Bunnell and cross-lock Bunnell repair techniques noticeably increased the resistance to initial gap formation and 5-mm gap formation. The tension-free cross-lock Bunnell repair demonstrated more resistance to initial and 5-mm gap formation, less elongation, and higher maximum tensile strength than the tension-free Bunnell repair technique. The only difference between the tensioned cross-lock Bunnell and tensioned Bunnell techniques was a larger resistance to 5-mm gap formation with the cross-lock Bunnell technique. Use of the simple instead of cross-lock suture configuration led to failure by suture cut out, as demonstrated fluoroscopically. Conclusion Based on these results, suture pretension decreases gapping and elongation after tendon repair, and those effects are stronger when using a cross-lock, rather than a regular Bunnell suture. However, pretension causes an unfavorable increase in the tendon diameter at the repair site, which may adversely affect wound healing.},
  language  = {en}
}
@article{JordanJansenMeffertetal.2021,
  author    = {Jordan, Martin C. and Jansen, Hendrik and Meffert, Rainer H. and Heintel, Timo M.},
  title     = {Comparing porous tantalum fusion implants and iliac crest bone grafts for spondylodesis of thoracolumbar burst fractures: Prospectice Cohort study},
  series = {Scientific Reports},
  volume    = {11},
  journal   = {Scientific Reports},
  number    = {1},
  doi       = {10.1038/s41598-021-96400-w},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-261706},
  year      = {2021},
  abstract  = {The aim of this study was to compare two different techniques of performing one-level spondylodesis for thoracolumbar burst fractures using either an autologous iliac crest bone graft (ICBG) or a porous tantalum fusion implant (PTFI). In a prospective nonrandomized study, 44 patients (20 women, 24 men; average age 43.1 +/- 13.2 years) suffering from severe thoracolumbar burst fractures were treated with combined anterior-posterior stabilization. An ICBG was used in 21 cases, and a PTFI was used in the other 23 cases. A two-year clinical and radiographic follow-up was carried out. There were no statistically significant differences in age, sex, localization/classification of the fracture, or visual analog scale (VAS) before injury between the two groups. All 44 patients were followed up for an average period of 533 days (range 173-1567). The sagittal spinal profile was restored by an average of 11.1 degrees (ICBG) vs. 14.3 degrees (PTFI) (monosegmental Cobb angle). Loss of correction until the last follow-up tended to be higher in the patients treated with ICBG than in those treated with PTFI (mean: 2.8 degrees vs. 1.6 degrees). Furthermore, significantly better restoration of the sagittal profile was obtained with the PTFI than with the iliac bone graft at the long-term follow-up (mean: ICBG 7.8 degrees, PTFI 12.3 degrees; p < 0.005). Short-segment posterior instrumentation combined with anterior one-level spondylodesis using either an ICBG or a PTFI resulted in sufficient correction of posttraumatic segmental kyphosis. PTFI might be a good alternative for autologous bone grafting and prevent donor site morbidities.},
  language  = {en}
}
@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{JordanBittrichFehskeetal.2017,
  author    = {Jordan, Martin C. and Bittrich, Leonie A. and Fehske, Kai and Meffert, Rainer H. and Jansen, Hendrik},
  title     = {A rare case of Hoffa fracture combined with lateral patellar dislocation},
  series = {Trauma Case Reports},
  volume    = {9},
  journal   = {Trauma Case Reports},
  doi       = {10.1016/j.tcr.2017.05.001},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-158315},
  pages     = {13-16},
  year      = {2017},
  abstract  = {The coronal unicondylar fracture of the distal femur (AO 33-B3) is a rare intraarticular injury within the weight bearing area of the knee, initially described by Albert Hoffa in 1904. We report an unusual combination of a Hoffa fracture with lateral patellar dislocation in a young adult. Our patient sustained the injury by a sudden twist of his leg during sports. He presented clinically with knee swelling, dislocation of the patella, and localized tenderness; unable to bare weight. After plane radiograph confirmed the injury, manual reduction of the patella was done by hyperextension of the knee and medialward pressure. Afterwards, a CT scan and MRI were conducted. The injury was surgically treated with lag-screws, locking-plate and MPFL-reconstruction.},
  language  = {en}
}
@article{JordanJaeckleScheidtetal.2020,
  author    = {Jordan, Martin C. and J{\"a}ckle, Veronika and Scheidt, Sebastian and Eden, Lars and Gilbert, Fabian and Heintel, Timo M. and Jansen, Hendrik and Meffert, Rainer H.},
  title     = {Ergebnisse nach Plattenstabilisierung der Symphysensprengung},
  series = {Der Unfallchirurg},
  volume    = {123},
  journal   = {Der Unfallchirurg},
  issn      = {0177-5537},
  doi       = {10.1007/s00113-020-00804-8},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-232447},
  pages     = {870-878},
  year      = {2020},
  abstract  = {Hintergrund Die Symphysensprengung mit entsprechender Diastase kann durch eine Symphysenplatte stabilisiert werden. Fragestellung Welche Beckenverletzungen werden mit einer Symphysenplatte stabilisiert und wie ist das Outcome? Material und Methoden Retrospektive Auswertung von 64 Patienten {\"u}ber einen Untersuchungszeitraum von 24 Monaten. Ergebnisse Es waren 56 Patienten m{\"a}nnlich, 8 weiblich und das mittlere Alter betrug 44 Jahre (SD ± 17). Unf{\"a}lle im Straßenverkehr waren der f{\"u}hrende Grund f{\"u}r die Beckenverletzung. Die Verteilung nach AO-Klassifikation zeigte sich wie folgt: 14-mal B1-, 10-mal B2-, 5‑mal B3-, 23-mal C1-, 9‑mal C2- und 3‑mal C3-Verletzungen. Die Verteilung nach Young und Burgess ergab: 9‑mal APC-I-, 18-mal APC-II-, 13-mal APC-III-, 9‑mal LC-I-, 3‑mal LC-II-, 2‑mal LC-III- und 10-mal VS-Verletzungen. Der mittlere Injury Severity Score (ISS) betrug 32 und die mittlere station{\"a}re Verweildauer 29 Tage (pos. Korrelation p ≤ 0,001). Im Verlauf war eine radiologische Implantatlockerung bei 52 Patienten nachweisbar. Therapierelevante Komplikationen gab es in 14 F{\"a}llen. Hierbei war das Implantatversagen (n = 8) der Hauptgrund f{\"u}r eine operative Revision. Diskussion Obwohl die radiologische Implantatlockerung h{\"a}ufig beobachtet wird, ist sie nur selten Grund f{\"u}r einen Revisionseingriff. Kommt es hingegen zum vollst{\"a}ndigen Implantatversagen, tritt dies meist innerhalb der ersten postoperativen Wochen auf und ist revisionsbed{\"u}rftig. Eine fr{\"u}hzeitige Abkl{\"a}rung durch R{\"o}ntgenbildgebung sollte bei Verdacht erfolgen.},
  language  = {de}
}