@article{PaulMiedenLeferingetal.2023, author = {Paul, Mila M. and Mieden, Hannah J. and Lefering, Rolf and Kupczyk, Eva K. and Jordan, Martin C. and Gilbert, Fabian and Meffert, Rainer H. and Sir{\´e}n, Anna-Leena and Hoelscher-Doht, Stefanie}, title = {Impact of a femoral fracture on outcome after traumatic brain injury — a matched-pair analysis of the TraumaRegister DGU\(^®\)}, series = {Journal of Clinical Medicine}, volume = {12}, journal = {Journal of Clinical Medicine}, number = {11}, issn = {2077-0383}, doi = {10.3390/jcm12113802}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-319363}, year = {2023}, abstract = {Traumatic brain injury (TBI) is the leading cause of death and disability in polytrauma and is often accompanied by concomitant injuries. We conducted a retrospective matched-pair analysis of data from a 10-year period from the multicenter database TraumaRegister DGU\(^®\) to analyze the impact of a concomitant femoral fracture on the outcome of TBI patients. A total of 4508 patients with moderate to critical TBI were included and matched by severity of TBI, American Society of Anesthesiologists (ASA) risk classification, initial Glasgow Coma Scale (GCS), age, and sex. Patients who suffered combined TBI and femoral fracture showed increased mortality and worse outcome at the time of discharge, a higher chance of multi-organ failure, and a rate of neurosurgical intervention. Especially those with moderate TBI showed enhanced in-hospital mortality when presenting with a concomitant femoral fracture (p = 0.037). The choice of fracture treatment (damage control orthopedics vs. early total care) did not impact mortality. In summary, patients with combined TBI and femoral fracture have higher mortality, more in-hospital complications, an increased need for neurosurgical intervention, and inferior outcome compared to patients with TBI solely. More investigations are needed to decipher the pathophysiological consequences of a long-bone fracture on the outcome after TBI.}, language = {en} } @article{HuflageFieberFaerberetal.2022, author = {Huflage, Henner and Fieber, Tabea and F{\"a}rber, Christian and Knarr, Jonas and Veldhoen, Simon and Jordan, Martin C. and Gilbert, Fabian and Bley, Thorsten Alexander and Meffert, Rainer H. and Grunz, Jan-Peter and Schmalzl, Jonas}, title = {Interobserver reliability of scapula fracture classifications in intra- and extra-articular injury patterns}, series = {BMC Musculoskeletal Disorders}, volume = {23}, journal = {BMC Musculoskeletal Disorders}, number = {1}, doi = {10.1186/s12891-022-05146-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-299795}, year = {2022}, abstract = {Background Morphology and glenoid involvement determine the necessity of surgical management in scapula fractures. While being present in only a small share of patients with shoulder trauma, numerous classification systems have been in use over the years for categorization of scapula fractures. The purpose of this study was to evaluate the established AO/OTA classification in comparison to the classification system of Euler and R{\"u}edi (ER) with regard to interobserver reliability and confidence in clinical practice. Methods Based on CT imaging, 149 patients with scapula fractures were retrospectively categorized by two trauma surgeons and two radiologists using the classification systems of ER and AO/OTA. To measure the interrater reliability, Fleiss kappa (κ) was calculated independently for both fracture classifications. Rater confidence was stated subjectively on a five-point scale and compared with Wilcoxon signed rank tests. Additionally, we computed the intraclass correlation coefficient (ICC) based on absolute agreement in a two-way random effects model to assess the diagnostic confidence agreement between observers. Results In scapula fractures involving the glenoid fossa, interrater reliability was substantial (κ = 0.722; 95\% confidence interval [CI] 0.676-0.769) for the AO/OTA classification in contrast to moderate agreement (κ = 0.579; 95\% CI 0.525-0.634) for the ER classification system. Diagnostic confidence for intra-articular fracture patterns was superior using the AO/OTA classification compared to ER (p < 0.001) with higher confidence agreement (ICC: 0.882 versus 0.831). For extra-articular fractures, ER (κ = 0.817; 95\% CI 0.771-0.863) provided better interrater reliability compared to AO/OTA (κ = 0.734; 95\% CI 0.692-0.776) with higher diagnostic confidence (p < 0.001) and superior agreement between confidence ratings (ICC: 0.881 versus 0.912). Conclusions The AO/OTA classification is most suitable to categorize intra-articular scapula fractures with glenoid involvement, whereas the classification system of Euler and R{\"u}edi appears to be superior in extra-articular injury patterns with fractures involving only the scapula body, spine, acromion and coracoid process.}, language = {en} } @article{JordanBroeerFischeretal.2022, author = {Jordan, Martin C. and Br{\"o}er, David and Fischer, Christian and Heilig, Philipp and Gilbert, Fabian and H{\"o}lscher-Doht, Stefanie and Kalogirou, Charis and Popp, Kevin and Grunz, Jan-Peter and Huflage, Henner and Jakubietz, Rafael G. and Erg{\"u}n, S{\"u}leyman and Meffert, Rainer H.}, title = {Development and preclinical evaluation of a cable-clamp fixation device for a disrupted pubic symphysis}, series = {Communications Medicine}, volume = {2}, journal = {Communications Medicine}, number = {1}, doi = {10.1038/s43856-022-00227-z}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-299800}, year = {2022}, abstract = {Background Traumatic separation of the pubic symphysis can destabilize the pelvis and require surgical fixation to reduce symphyseal gapping. The traditional approach involves open reduction and the implantation of a steel symphyseal plate (SP) on the pubic bone to hold the reposition. Despite its widespread use, SP-fixation is often associated with implant failure caused by screw loosening or breakage. Methods To address the need for a more reliable surgical intervention, we developed and tested two titanium cable-clamp implants. The cable served as tensioning device while the clamp secured the cable to the bone. The first implant design included a steel cable anterior to the pubic symphysis to simplify its placement outside the pelvis, and the second design included a cable encircling the pubic symphysis to stabilize the anterior pelvic ring. Using highly reproducible synthetic bone models and a limited number of cadaver specimens, we performed a comprehensive biomechanical study of implant stability and evaluated surgical feasibility. Results We were able to demonstrate that the cable-clamp implants provide stability equivalent to that of a traditional SP-fixation but without the same risks of implant failure. We also provide detailed ex vivo evaluations of the safety and feasibility of a trans-obturator surgical approach required for those kind of fixation. Conclusion We propose that the developed cable-clamp fixation devices may be of clinical value in treating pubic symphysis separation.}, language = {en} } @article{HeiligFaerberPauletal.2022, author = {Heilig, Philipp and Faerber, Lars-Christopher and Paul, Mila M. and Kupczyk, Eva and Meffert, Rainer H. and Jordan, Martin C. and Hoelscher-Doht, Stefanie}, title = {Plate osteosynthesis combined with bone cement provides the highest stability for tibial head depression fractures under high loading conditions}, series = {Scientific Reports}, volume = {12}, journal = {Scientific Reports}, number = {1}, doi = {10.1038/s41598-022-19107-6}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-299782}, year = {2022}, abstract = {Older patients sustaining tibial head depression fractures often cannot follow the post-operative rehabilitation protocols with partial weight-bearing of the affected limb, leading to osteosynthesis failure, cartilage step-off and arthritis development. Therefore, the aim of this study was to analyse the biomechanical performance of different types of osteosyntheses alone and in combination with bone cement simulating cyclically high loading conditions of tibial head depression fractures. Lateral tibial head depression fractures (AO: 41-B2.2; Schatzker type III) were created in synthetic bones and stabilized using three different osteosyntheses alone and in combination with a commonly used bone cement (chronOS™): 2 screws, 4 screws in the jail technique and a lateral angle-stable buttress plate. After fixation, the lateral tibial plateau was axially loaded in two, from each other independent testing series: In the first test protocol, 5000 cycles with 500 N and in the end load-to-failure tests were performed. In the second test protocol, the cyclic loading was increased to 1000 N. Parameters of interest were the displacement of the articular fracture fragment, the stiffness and the maximum load. The osteosyntheses revealed a higher stiffness in combination with bone cement compared to the same type of osteosynthesis alone (e.g., 500 N level: 2 screws 383 ± 43 N/mm vs. 2 screws + chronOs 520 ± 108 N/mm, increase by 36\%, p < 0.01; 4 screws 368 ± 97 N/mm vs. 4 screws + chronOS 516 ± 109 N/mm, increase by 40\%, p < 0.01; plate: 509 ± 73 N/mm vs. plate + chronOs 792 ± 150 N/mm, increase by 56\%, p < 0.01). Bone cement reduced the displacement of the plate significantly (500 N level: plate: 8.9 ± 2.8 mm vs. plate + chronOs: 3.1 ± 1.4 mm, reduction by 65\%, p < 0.01; 1000 N level: 16.9 ± 3.6 mm vs 5.6 ± 1.3 mm, reduction by 67\%, p < 0.01). Thus, the highest stiffness and lowest displacement values were found when using the plate with bone cement in both loading conditions (500 N level: 2 screws + chronOs 3.7 ± 1.3 mm, 4 screws + chronOs 6.2 ± 2.4 mm; 1000 N level: 2 screws + chronOs 6.5 ± 1.2 mm, 4 screws + chronOs 5.7 ± 0.8 mm). From a biomechanical perspective, plate osteosynthesis of tibial head depression fractures should always be combined with bone cement, provides higher stability than 2-screw and 4-screw fixation and is a valid treatment option in cases where extraordinary stability is required.}, 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{KippnichDuempertSchorscheretal.2022, author = {Kippnich, Maximilian and Duempert, Maximilian and Schorscher, Nora and Jordan, Martin C. and Kunz, Andreas S. and Meybohm, Patrick and Wurmb, Thomas}, title = {Simultaneous treatment of trauma patients in a dual room trauma suite with integrated movable sliding gantry CT system: an observational study}, series = {Scientific Reports}, volume = {12}, journal = {Scientific Reports}, number = {1}, doi = {10.1038/s41598-022-20491-2}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-299695}, year = {2022}, abstract = {The trauma center of the University Hospital Wuerzburg has developed an advanced trauma pathway based on a dual-room trauma suite with an integrated movable sliding gantry CT-system. This enables simultaneous CT-diagnostics and treatment of two trauma patients. The focus of this study was to investigate the quality of the concept based on defined outcome criteria in this specific setting (time from arrival to initiation of CT scan: tCT; time from arrival to initiation of emergency surgery: tES). We analyzed all trauma patients admitted to the hospital's trauma suite from 1st May 2019 through 29th April 2020. Two subgroups were defined: trauma patients, who were treated without a second trauma patient present (group 1) and patients, who were treated simultaneously with another trauma patient (group 2). Simultaneous treatment was defined as parallel arrival within a period of 20 min. Of 423 included trauma patients, 46 patients (10.9\%) were treated simultaneously. Car accidents were the predominant trauma mechanism in this group (19.6\% vs. 47.8\%, p < 0.05). Prehospital life-saving procedures were performed with comparable frequency in both groups (intubation 43.5\% vs. 39\%, p = 0.572); pleural drainage 3.2\% vs. 2.2\%, p = 0.708; cardiopulmonary resuscitation 5\% vs. 2.2\%, p = 0.387). At hospital admission, patients in group 2 suffered significantly more pain (E-problem according to Advanced Trauma Life Support principles©; 29.2\% vs. 45.7\%, p < 0.05). There were no significant differences in the clinical treatment (emergency procedures, vasopressor and coagulant therapy, and transfusion of red blood cells). tCT was 6 (4-10) minutes (median and IQR) in group 1 and 8 (5-15.5) minutes in group 2 (p = 0.280). tES was 90 (78-106) minutes in group 1 and 99 (97-108) minutes in group 2 (p = 0.081). The simultaneous treatment of two trauma patients in a dual-room trauma suite with an integrated movable sliding gantry CT-system requires a medical, organizational, and technical concept adapted to this special setting. Despite the oftentimes serious and life-threatening injuries, optimal diagnostic and therapeutic procedures can be guaranteed for two simultaneous trauma patients at an individual medical level in consistent quality.}, language = {en} } @article{JordanJaeckleScheidtetal.2021, author = {Jordan, Martin C. and J{\"a}ckle, Veronika and Scheidt, Sebastian and Gilbert, Fabian and H{\"o}lscher-Doht, Stefanie and Erg{\"u}n, S{\"u}leyman and Meffert, Rainer H. and Heintel, Timo M.}, title = {Trans-obturator cable fixation of open book pelvic injuries}, series = {Scientific Reports}, volume = {11}, journal = {Scientific Reports}, number = {1}, doi = {10.1038/s41598-021-92755-2}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-261212}, year = {2021}, abstract = {Operative treatment of ruptured pubic symphysis by plating is often accompanied by complications. Trans-obturator cable fixation might be a more reliable technique; however, have not yet been tested for stabilization of ruptured pubic symphysis. This study compares symphyseal trans-obturator cable fixation versus plating through biomechanical testing and evaluates safety in a cadaver experiment. APC type II injuries were generated in synthetic pelvic models and subsequently separated into three different groups. The anterior pelvic ring was fixed using a four-hole steel plate in Group A, a stainless steel cable in Group B, and a titan band in Group C. Biomechanical testing was conducted by a single-leg-stance model using a material testing machine under physiological load levels. A cadaver study was carried out to analyze the trans-obturator surgical approach. Peak-to-peak displacement, total displacement, plastic deformation and stiffness revealed a tendency for higher stability for trans-obturator cable/band fixation but no statistical difference to plating was detected. The cadaver study revealed a safe zone for cable passage with sufficient distance to the obturator canal. Trans-obturator cable fixation has the potential to become an alternative for symphyseal fixation with less complications.}, 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{FuchsHeiligMcDonoghetal.2020, author = {Fuchs, Konrad F. and Heilig, Philipp and McDonogh, Miriam and Boelch, Sebastian and Gbureck, Uwe and Meffert, Rainer H. and Hoelscher-Doht, Stefanie and Jordan, Martin C.}, title = {Cement-augmented screw fixation for calcaneal fracture treatment: a biomechanical study comparing two injectable bone substitutes}, series = {Journal of Orthopaedic Surgery and Research}, volume = {15}, journal = {Journal of Orthopaedic Surgery and Research}, doi = {10.1186/s13018-020-02009-6}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230336}, year = {2020}, abstract = {Background The role of cement-augmented screw fixation for calcaneal fracture treatment remains unclear. Therefore, this study was performed to biomechanically analyze screw osteosynthesis by reinforcement with either a calcium phosphate (CP)-based or polymethylmethacrylate (PMMA)-based injectable bone cement. Methods A calcaneal fracture (Sanders type IIA) including a central cancellous bone defect was generated in 27 synthetic bones, and the specimens were assigned to 3 groups. The first group was fixed with four screws (3.5 mm and 6.5 mm), the second group with screws and CP-based cement (Graftys (R) QuickSet; Graftys, Aix-en-Provence, France), and the third group with screws and PMMA-based cement (Traumacem (TM) V+; DePuy Synthes, Warsaw, IN, USA). Biomechanical testing was conducted to analyze peak-to-peak displacement, total displacement, and stiffness in following a standardized protocol. Results The peak-to-peak displacement under a 200-N load was not significantly different among the groups; however, peak-to-peak displacement under a 600- and 1000-N load as well as total displacement exhibited better stability in PMMA-augmented screw osteosynthesis compared to screw fixation without augmentation. The stiffness of the construct was increased by both CP- and PMMA-based cements. Conclusion Addition of an injectable bone cement to screw osteosynthesis is able to increase fixation strength in a biomechanical calcaneal fracture model with synthetic bones. In such cases, PMMA-based cements are more effective than CP-based cements because of their inherently higher compressive strength. However, whether this high strength is required in the clinical setting for early weight-bearing remains controversial, and the non-degradable properties of PMMA might cause difficulties during subsequent interventions in younger patients.}, 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{JordanZimmermannGhoetal.2016, author = {Jordan, Martin C. and Zimmermann, Christina and Gho, Sheridan A. and Frey, S{\"o}nke P. and Blunk, Torsten and Meffert, Rainer H. and Hoelscher-Doht, Stefanie}, title = {Biomechanical analysis of different osteosyntheses and the combination with bone substitute in tibial head depression fractures}, series = {BMC Musculoskeletal Disorders}, volume = {17}, journal = {BMC Musculoskeletal Disorders}, number = {287}, doi = {10.1186/s12891-016-1118-4}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-161201}, year = {2016}, abstract = {Background Tibial head depression fractures demand a high level of fracture stabilization to prevent a secondary loss of reduction after surgery. Elderly individuals are at an increased risk of developing these fractures, and biomechanical investigations of the fractures are rare. Therefore, the aim of this study was to systematically analyze different types of osteosyntheses in combination with two commonly used bone substitutes. Methods Lateral tibial head depression fractures were created in synthetic bones. After reduction, the fractures were stabilized with eight different treatment options of osteosynthesis alone or in combination with a bone substitute. Two screws, 4 screws and a lateral buttress plate were investigated. As a bone substitute, two common clinically used calcium phosphate cements, Norian® Drillable and ChronOS™ Inject, were applied. Displacement of the articular fracture fragment (mm) during cyclic loading, stiffness (N/mm) and maximum load (N) in Load-to-Failure tests were measured. Results The three different osteosyntheses (Group 1: 2 screws, group 2: 4 screws, group 3: plate) alone revealed a significantly higher displacement compared to the control group (Group 7: ChronOS™ Inject only) (Group 1, 7 [p < 0.01]; group 2, 7 [p = 0.04]; group 3, 7 [p < 0.01]). However, the osteosyntheses in combination with bone substitute exhibited no differences in displacement compared to the control group. The buttress plate demonstrated a higher normalized maximum load than the 2 and 4 screw osteosynthesis. Comparing the two different bone substitutes to each other, ChronOS™ inject had a significantly higher stiffness and lower displacement than Norian® Drillable. Conclusions The highest biomechanical stability under maximal loading was provided by a buttress plate osteosynthesis. A bone substitute, such as the biomechanically favorable ChronOS™ Inject, is essential to reduce the displacement under lower loading.}, language = {en} } @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{SchmidtJordanHoelscherDohtetal.2014, author = {Schmidt, Karsten and Jordan, Martin C. and H{\"o}lscher-Doht, Stefanie and Jakubietz, Michael G. and Jakubietz, Rafael G. and Meffert, Rainer H.}, title = {Suture material for flexor tendon repair: 3-0 V-Loc versus 3-0 Stratafix in a biomechanical comparison ex vivo}, doi = {10.1186/s13018-014-0072-9}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-110419}, year = {2014}, abstract = {Background Barbed suture material offers the possibility of knotless flexor tendon repair, as suggested in an increasing number of biomechanical studies. There are currently two different absorbable barbed suture products available, V-Loc™ and Stratafix™, and both have not been compared to each other with regard to flexor tendon repair. The purpose of this study was to evaluate both suture materials for primary stability under static and cyclic loading in a biomechanical ex vivo model. Methods Forty fresh porcine flexor digitorum profundus tendons were randomized in two groups. A four-strand modified Kessler suture technique was used to repair the tendon either with a 3-0 V-Loc™ or 3-0 Stratafix™ without a knot. Parameters of interest were mode of failure, 2-mm gap formation force, displacement, stiffness and maximum load under static and cyclic testing. Results The maximum load was 42.3 ± 7.2 for the Stratafix™ group and 50.7 ± 8.8 N for the V-Loc™ group. Thus, the ultimate tensile strength was significantly higher for V-Loc™ (p < 0.05). The 2-mm gap occurred at 24.8 ± 2.04 N in the Stratafix™ group in comparison to 26.5 ± 2.12 N in the V-Loc™ group (n.s.). Displacement was 2.65 ± 0.56 mm in the V-Loc™ group and 2.71 ± 0.59 mm in the Stratafix™ group (n.s.). Stiffness was 4.24 ± 0.68 (N/mm) in the V-Loc™ group and 3.85 ± 0.55 (N/mm) the Stratafix™ group (n.s.). Those measured differences were not significant. Conclusion V-Loc™ demonstrates a higher maximum load in tendon reconstruction. The differences in 2-mm gap formation force, displacement and stiffness were not significant. Hereby, the V-Loc™ has an advantage when used as unidirectional barbed suture for knotless flexor tendon repair.}, language = {en} }