TY - JOUR A1 - Hoelscher‑Doht, Stefanie A1 - Kladny, A.-M. A1 - Paul, M. M. A1 - Eden, L. A1 - Buesse, M. A1 - Meffert, R. H. T1 - Low-profile double plating versus dorsal LCP in stabilization of the olecranon fractures JF - Archives of Orthopaedic and Trauma Surgery N2 - Introduction Proximal ulna fractures are common in orthopaedic surgery. Comminuted fractures require a high primary stability by the osteosynthesis, to allow an early functional rehabilitation as fast as possible, to reduce long-term limitations of range of motion. Classical dorsal plating is related to wound healing problems due to the prominence of the implant. New low-profile double plates are available addressing the soft tissue problems by positioning the plates at the medial and lateral side. This study analysed whether, under high loading conditions, these new double plates provide an equivalent stability as compared to the rigid olecranon locking compression plate (LCP). Materials and methods In Sawbones, Mayo Type IIB fractures were simulated and stabilized by plate osteosyntheses: In group one, two low-profile plates were placed. In group two, a single dorsal plate (LCP) was used. The bones was than cyclically loaded simulating flexion grades of 0°, 30°, 60° and 90° of the elbow joint with increasing tension forces (150 , 150 , 300 and 500 N). The displacement and fracture gap movement were recorded. In the end, in load-to-failure tests, load at failure and mode of failure were determined. Results No significant differences were found for the displacement and fracture gap widening during cyclic loading. Under maximum loading, the double plates revealed a comparable load at failure like the single dorsal plate (LCP). The double plates failed with a proximal screw pull-out of the plate, whereas in the LCP group, in 10 out of 12 specimens the mode of failure was a diaphyseal shaft fracture at the distal plate peak. Conclusion Biomechanically, the double plates are a good alternative to the dorsal LCP providing a high stability under high loading conditions and, at the same, time reducing the soft tissue irritation by a lateral plate position. KW - olecranon KW - plate KW - biomechanical KW - fracture KW - low profile Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-235844 SN - 0936-8051 VL - 145 ER - TY - JOUR A1 - Ochman, S. A1 - Vordemvenne, T. A1 - Paletta, J. A1 - Raschke, M. J. A1 - Meffert, R. H. A1 - Doht, S. T1 - Experimental Fracture Model versus Osteotomy Model in Metacarpal Bone Plate Fixation JF - The Scientific World Journal N2 - Introduction Osteotomy or fracture models can be used to evaluate mechanical properties of fixation techniques of the hand skeleton in vitro. Although many studies make use of osteotomy models, fracture models simulate the clinical situation more realistically. This study investigates monocortical and bicortical plate fixation on metacarpal bones considering both aforementioned models to decide which method is best suited to test fixation techniques. Methods Porcine metacarpal bones (n =40) were randomized into 4 groups. In groups I and II bones were fractured with a modified 3-point bending test. The intact bones represented a further control group to which the other groups after fixation were compared. In groups III and IV a standard osteotomy was carried out. Bones were fixated with plates monocortically (group I, III) and bicortically (group II, IV) and tested for failure. Results Bones fractured at a mean maximum load of 482.8N±104.8N with a relative standard deviation (RSD) of 21.7%, mean stiffness was 122.3±35 N/mm. In the fracture model, there was a significant difference (P = 0.01) for maximum load of monocortically and bicortically fixed bones in contrast to the osteotomy model (P = 0.9). Discussion. In the fracture model, because one can use the same bone for both measurements in the intact state and the bone-plate construct states, the impact of inter-individual differences is reduced. In contrast to the osteotomy model there are differences between monocortical and bicortical fixations in the fracture model. Thus simulation of the in vivo situation is better and seems to be suitable for the evaluation of mechanical properties of fixation techniques on metacarpals KW - biomechanics KW - fracture model KW - metacarpal KW - osteotomy KW - plate fixation Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-178840 N1 - http://dx.doi.org/10.1100/2011/465371 VL - 11 ER - TY - JOUR A1 - Gilbert, F. A1 - Schneemann, C. A1 - Scholz, C. J. A1 - Kickuth, R. A1 - Meffert, R. H. A1 - Wildenauer, R. A1 - Lorenz, U. A1 - Kellersmann, R. A1 - Busch, A. T1 - Clinical implications of fracture-associated vascular damage in extremity and pelvic trauma JF - BMC Muscuskeletal Disorders N2 - Background: Vascular damage in polytrauma patients is associated with high mortality and morbidity. Therefore, specific clinical implications of vascular damage with fractures in major trauma patients are reassessed. Methods: This comprehensive nine-year retrospective single center cohort study analyzed demography, laboratory, treatment and outcome data from 3689 patients, 64 patients with fracture-associated vascular injuries were identified and were compared to a control group. Results: Vascular damage occurred in 7% of patients with upper and lower limb and pelvic fractures admitted to the trauma room. Overall survival was 80% in pelvic fracture and 97% in extremity fracture patients and comparable to non-vascular trauma patients. Additional arterial damage required substantial fluid administration and was visible as significantly anemia and disturbed coagulation tests upon admission. Open procedures were done in over 80% of peripheral extremity vascular damage. Endovascular procedures were predominant (87%) in pelvic injury. Conclusion: Vascular damage is associated with high mortality rates especially in combination with pelvic fractures. Initial anemia, disturbed coagulation tests and the need for extensive pre-clinical fluid substitution were observed in the cohort with vascular damage. Therefore, fast diagnosis and early interventional and surgical procedures are necessary to optimize patient-specific outcome. KW - endovascular repair KW - extremity trauma KW - fracture-associated vascular damage KW - level of evidence: IV KW - surgical trauma room KW - pelvic trauma Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176252 VL - 19 IS - 404 ER - TY - JOUR A1 - Gilbert, F. A1 - Meffert, R. H. A1 - Schmalzl, J. A1 - Weng, A. M. A1 - Köstler, H. A1 - Eden, L. T1 - Grade of retraction and tendon thickness correlates with MR-spectroscopically measured amount of fatty degeneration in full thickness supraspinatus tears JF - BMC Musculoskeletal Disorders N2 - Background: The amount of fatty degeneration (FD) has major impact on the clinical result and cuff integrity after rotator cuff repair. A quantitative analysis with magnet resonance imaging (MRI) spectroscopy was employed to analyze possible correlation of FD with tendon retraction, tendon thickness and patients’ characteristics in full thickness supraspinatus tears. Methods: Forty-two patients with full-thickness supraspinatus tears underwent shoulder MRI including an experimental spectroscopic sequence allowing quantification of the fat fraction in the supraspinatus muscle belly. The amount of fatty degeneration was correlated with tendon retraction, tendon thickness, patients’ age, gender, smoker status, symptom duration and body mass index (BMI). Patients were divided in to three groups of retraction (A) 0-10 mm (n=), (B) 11-20 mm (n=) and (C) < 21 mm (n=) and the means of FD for each group were calculated. Results: Tendon retraction (R = 0.6) and symptom duration (R = 0.6) correlated positively, whereas tendon thickness correlated negatively (R = − 0.6) with the amount of FD. The fat fraction increased significantly with tendon retraction: Group (A) showed a mean fat mount of 3.7% (±4%), group (B) of 16.7% (±8.2%) and group (C) of 37.5% (±19%). BMI, age and smoker-status only showed weak to moderate correlation with the amount of FD in this cohort. Conclusion: MRI spectroscopy revealed significantly higher amount of fat with increasing grade of retraction, symptom duration and decreased tendon thickness. Thus, these parameters may indirectly be associated with the severity of tendon disease. KW - rotator cuff KW - MRI KW - spectroscopy KW - muscle degeneration Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176116 VL - 19 IS - 197 ER - TY - JOUR A1 - Gilbert, F. A1 - Heintel, T. M. A1 - Jakubietz, M. G. A1 - Köstler, H. A1 - Sebald, C. A1 - Meffert, R. H. A1 - Weng, A. M. T1 - Quantitative MRI comparison of multifidus muscle degeneration in thoracolumbar fractures treated with open and minimally invasive approach JF - BMC Musculoskeletal Disorders N2 - Background: Minimally invasive pedicle screw fixation has less approach-related morbidity than open screw placement and is allegedly less traumatizing on paravertebral muscles, as there is no requirement to mobilize and retract the adjacent muscle portion. The approach-related long-term effects to the morphology of the paravertebral muscles are unknown. The purpose of this study was to compare the long-term amount of fatty degeneration of the multifidus muscle in patients treated with a classical open or a minimally invasive approach. Methods: Fourteen Patients meeting inclusion criteria were selected. In all patients a singular fracture of the thoracolumbar spine with a two-level posterior instrumentation was treated, either using an open approach or a minimally invasive approach. All patients underwent quantitative MRI spectroscopy for quantification of the fatty degeneration in the multifidus muscle as a long-term proof for muscle loss after minimum 4-year follow-up. Clinical outcome was assessed using Oswestry Low Back Pain Disability Questionnaire, SF-36 and VA-scale for pain. Results: The minimally invasive approach group failed to show less muscle degeneration in comparison to the open group. Total amount of fatty degeneration was 14.22% in the MIS group and 12.60% in the open group (p = 0.64). In accordance to MRI quantitative results there was no difference in the clinical outcome after a mean follow up of 5.9 years (±1.8). Conclusion: As short-term advantages of minimal invasive screw placement have been widely demonstrated, no advantage of the MIS, displaying a significant difference in the amount of fatty degeneration and resulting in a better clinical outcome could be found. Besides the well-known short-term advantage of minimally invasive pedicle screw placement, a long-term advantage, such as less muscle degeneration and thus superior clinical results, compared to the open approach could not be shown. KW - dorsal instrumentation KW - minimal invasive surgery KW - muscle degeneration KW - spine trauma Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-175742 VL - 19 IS - 75 ER - TY - JOUR A1 - Boelch, S. P. A1 - Jansen, H. A1 - Meffert, R. H. A1 - Frey, S. P. T1 - Six Sesamoid Bones on Both Feet: Report of a Rare Case JF - Journal of Clinical and Diagnostic Research N2 - There is a variation of the total number of distinct bones in the human in the literature. This difference is mainly caused by the variable existence of sesamoid bones. Sesamoid bones at the first MTP are seen regularly. In contrast additional sesamoid bones at the divond to fifth MTP are rare. We report a case of additional sesamoid bones at every metatarsophalangeal joint (MTP) of both feet. A 22-year-old female Caucasian presented with weight-dependent pain of the divond MTP of the left foot. In the radiographs of both feet additional sesamoid bones at every MTP could be seen. This case reports a very rare variation in human anatomy. A similar case has not been displayed to the academic society and therefore should be acknowledged. KW - anatomy KW - genetics KW - variation Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126073 VL - 9 IS - 8 ER -