@article{TrivanovicVolkmannStoeckletal.2023,
  author    = {Trivanovic, Drenka and Volkmann, Noah and Stoeckl, Magdalena and Tertel, Tobias and Rudert, Maximilian and Giebel, Bernd and Herrmann, Marietta},
  title     = {Enhancement of immunosuppressive activity of mesenchymal stromal cells by platelet-derived factors is accompanied by apoptotic priming},
  series = {Stem Cell Reviews and Reports},
  volume    = {19},
  journal   = {Stem Cell Reviews and Reports},
  number    = {3},
  doi       = {10.1007/s12015-022-10471-4},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324669},
  pages     = {713-733},
  year      = {2023},
  abstract  = {The pro-inflammatory phase of bone healing, initiated by platelet activation and eventually hematoma formation, impacts bone marrow mesenchymal stromal cells (MSCs) in unknown ways. Here, we created platelet-rich plasma (PRP) hydrogels to study how platelet-derived factors modulate functional properties of encapsulated MSCs in comparison to a non-inflammatory fibrin (FBR) hydrogel environment. MSCs were isolated from human bone marrow, while PRP was collected from pooled apheresis thrombocyte concentrates and used for hydrogel preparation. After their encapsulation in hydrogels for 72 h, retrieved MSCs were analyzed for immunomodulatory activities, apoptosis, stem cell properties, senescence, CD9\(^+\), CD63\(^+\) and CD81\(^+\) extracellular vesicle (EV) release, and metabolism-related changes. PRP-hydrogels stimulated immunosuppressive functions of MSCs, along with their upregulated susceptibility to cell death in communication with PBMCs and augmented caspase 3/7 activity. We found impaired clonal growth and cell cycle progression, and more pronounced β-galactosidase activity as well as accumulation of LC3-II-positive vacuoles in PRP-MSCs. Stimuli derived from PRP-hydrogels upregulated AKT and reduced mTOR phosphorylation in MSCs, which suggests an initiation of survival-related processes. Our results showed that PRP-hydrogels might represent a metabolically stressful environment, inducing acidification of MSCs, reducing polarization of the mitochondrial membrane and increasing lipid accumulation. These features were not detected in FBR-MSCs, which showed reduced CD63\(^+\) and CD81\(^+\) EV production and maintained clonogenicity. Our data revealed that PRP-derived hematoma components cause metabolic adaptation of MSCs followed by increased immune regulatory functions. For the first time, we showed that PRP stimuli represent a survival challenge and "apoptotic priming" that are detrimental for stem cell-like growth of MSCs and important for their therapeutic consideration.},
  language  = {en}
}
@article{SteinertSchroederSefrinetal.2022,
  author    = {Steinert, Andre F. and Schr{\"o}der, Lennart and Sefrin, Lukas and Janßen, Bj{\"o}rn and Arnholdt, J{\"o}rg and Rudert, Maximilian},
  title     = {The impact of total knee replacement with a customized cruciate-retaining implant design on patient-reported and functional outcomes},
  series = {Journal of Personalized Medicine},
  volume    = {12},
  journal   = {Journal of Personalized Medicine},
  number    = {2},
  issn      = {2075-4426},
  doi       = {10.3390/jpm12020194},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-312746},
  year      = {2022},
  abstract  = {Purpose: To treat patients with tricompartimental knee osteoarthritis (OA), a customized cruciate-retaining total knee arthroplasty (CCR-TKA) system can be used, including both individualized instrumentation and implants. The objective of this monocentric cohort study was to analyze patient-reported and functional outcomes in a series of patients implanted with the second generation of this customized implant. Methods: At our arthroplasty center, we prospectively recruited a cohort of patients with tricompartmental gonarthrosis to be treated with total knee replacement (TKA) using a customized cruciate-retaining (CCR) implant design. Inclusion criteria for patients comprised the presence of intact posterior cruciate and collateral ligaments and a knee deformity that was restricted to <15° varus, valgus, or flexion contracture. Patients were assessed for their range of motion (ROM), Knee Society Score (KSS), Western Ontario and McMaster University osteoarthritis index (WOMAC), and short form (SF)-12 physical and mental scores, preoperatively, at 3 and 6 months, as well as at 1, 2, 3, and 5 years of follow-up (FU) postoperatively. Results: The average age of the patient population was 64 years (range: 40-81), the average BMI was 31 (range: 23-42), and in total, 28 female and 45 male patients were included. Implant survivorship was 97.5\% (one septic loosening) at an average follow-up of 2.5 years. The KSS knee and function scores improved significantly (p < 0.001) from, respectively, 41 and 53 at the pre-operative visit, to 92 and 86, respectively, at the 5-year post-operative time point. The SF-12 Physical and Mental scores significantly (p < 0.001) improved from the pre-operative values of 28 and 50, to 50 and 53 at the 5-year FU, respectively. Patients experienced significant improvements in their overall knee range of motion, from 106° at the preoperative visit to 122°, on average, 5 years postoperatively. The total WOMAC score significantly (p < 0.001) improved from 49.1 preoperatively to 11.4 postoperatively at 5-year FU. Conclusions: Although there was no comparison to other implants within this study, patients reported high overall satisfaction and improvement in functional outcomes within the first year from surgery, which continued over the following years. These mid-term results are excellent compared with those reported in the current literature. Comparative long-term studies with this device are needed. Level of evidence 3b (individual case-control study).},
  language  = {en}
}
@article{vonHertzbergBoelchLuedemannRudertetal.2022,
  author    = {von Hertzberg-Boelch, Sebastian Philipp and Luedemann, Martin and Rudert, Maximilian and Steinert, Andre F.},
  title     = {PMMA bone cement: antibiotic elution and mechanical properties in the context of clinical use},
  series = {Biomedicines},
  volume    = {10},
  journal   = {Biomedicines},
  number    = {8},
  issn      = {2227-9059},
  doi       = {10.3390/biomedicines10081830},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-281708},
  year      = {2022},
  abstract  = {This literature review discusses the use of antibiotic loaded polymethylmethacrylate bone cements in arthroplasty. The clinically relevant differences that have to be considered when antibiotic loaded bone cements (ALBC) are used either for long-term implant fixation or as spacers for the treatment of periprosthetic joint infections are outlined. In this context, in vitro findings for antibiotic elution and material properties are summarized and transferred to clinical use.},
  language  = {en}
}
@article{BoelchRueecklStrecketal.2021,
  author    = {Boelch, Sebastian Philipp and R{\"u}eckl, Kilian and Streck, Laura Elisa and Szewczykowski, Viktoria and Weißenberger, Manuel and Jakuscheit, Axel and Rudert, Maximilian},
  title     = {Diagnosis of chronic infection at total hip arthroplasty revision is a question of definition},
  series = {Biomed Research International},
  volume    = {2021},
  journal   = {Biomed Research International},
  doi       = {10.1155/2021/8442435},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-265762},
  year      = {2021},
  abstract  = {Purpose. Contradicting definitions of periprosthetic joint infection (PJI) are in use. Joint aspiration is performed before total hip arthroplasty (THA) revision. This study investigated the influence of PJI definition on PJI prevalence at THA revision. Test quality of prerevision aspiration was evaluated for the different PJI definitions. Methods. 256 THA revisions were retrospectively classified to be infected or not infected. Classification was performed according to the 4 different definitions proposed by the Musculoskeletal Infection Society (MSIS), the Infectious Diseases Society of America (IDSA), the International Consensus Meeting (ICM), and the European Bone and Joint Infection Society (EBJIS). Only chronic PJIs were included. Results. PJI prevalence at revision significantly correlated with the applied PJI definition (p=0.01, Cramer's V=0.093). PJI prevalence was 20.7\% for the MSIS, 25.4\% for the ICM, 28.1\% for the IDSA, and 32.0\% for the EBJIS definition. For synovial fluid white blood cell count, the best ROC-AUC for predicting PJI was 0.953 in combination with the MSIS definition. Conclusion. PJI definition significantly influences the rate of diagnosed PJIs at THA revision. Synovial fluid white blood cell count is a reliable means to rule out PJI. In cases with a borderline high synovial white blood cell count before THA revision as the only sign of chronic PJI, an extended diagnostic work-up should be considered.},
  language  = {en}
}
@article{EidmannEwaldBoelchetal.2021,
  author    = {Eidmann, Annette and Ewald, Andrea and Boelch, Sebastian P. and Rudert, Maximilian and Holzapfel, Boris M. and Stratos, Ioannis},
  title     = {In vitro evaluation of antibacterial efficacy of vancomycin-loaded suture tapes and cerclage wires},
  series = {Journal of Materials Science: Materials in Medicine},
  volume    = {32},
  journal   = {Journal of Materials Science: Materials in Medicine},
  number    = {4},
  doi       = {10.1007/s10856-021-06513-x},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-260089},
  pages     = {42},
  year      = {2021},
  abstract  = {Usage of implants containing antibiotic agents has been a common strategy to prevent implant related infections in orthopedic surgery. Unfortunately, most implants with microbial repellent properties are characterized by accessibility limitations during daily clinical practice. Aim of this in vitro study was to investigate whether suture tapes and cerclage wires, which were treated with vancomycin, show a sustainable antibacterial activity. For this purpose, we used 24 stainless steel wire cerclages and 24 ultra-high molecular weight polyethylene and polyester suture tape test bodies. The test bodies were incubated for 30 min. in 100 mg/ml vancomycin solution or equivalent volumes of 0.9\% NaCl. After measuring the initial solution uptake of the test bodies, antibacterial efficacy via agar diffusion test with Staphylococcus aureus and vancomycin elution tests were performed 1, 2, 3, and 6 days after incubation. Vancomycin-loaded tapes as well as vancomycin-loaded cerclage wires demonstrated increased bacterial growth inhibition when compared to NaCl-treated controls. Vancomycin-loaded tapes showed an additional twofold and eightfold increase of bacterial growth inhibition compared to vancomycin-loaded wires at day 1 and 2, respectively. Elution tests at day 1 revealed high levels of vancomycin concentration in vancomycin loaded tapes and wires. Additionally, the concentration in vancomycin loaded tapes was 14-fold higher when compared to vancomycin loaded wires. Incubating suture tapes and cerclage wires in vancomycin solution showed a good short-term antibacterial activity compared to controls. Considering the ease of vancomycin application on suture tapes or wires, our method could represent an attractive therapeutic strategy in biofilm prevention in orthopedic surgery.},
  language  = {en}
}
@article{ProdingerLazicHorasetal.2020,
  author    = {Prodinger, Peter Michael and Lazic, Igor and Horas, Konstantin and Burgkart, Rainer and von Eisenhart-Rothe, R{\"u}diger and Weissenberger, Manuel and Rudert, Maximilian and Holzapfel, Boris Michael},
  title     = {Revision Arthroplasty Through the Direct Anterior Approach Using an Asymmetric Acetabular Component},
  series = {Journal of Clinical Medicine},
  volume    = {9},
  journal   = {Journal of Clinical Medicine},
  number    = {9},
  issn      = {2077-0383},
  doi       = {10.3390/jcm9093031},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-213184},
  year      = {2020},
  abstract  = {Despite increasing numbers of primary hip arthroplasties performed through the direct anterior approach (DAA), there is a lack of literature on DAA revision arthroplasty. The present study was performed in order to evaluate outcomes and revision rates after revision through the DAA using an asymmetric acetabular component with optional intra- and extramedullary fixation. In a retrospective cohort study, we analyzed prospectively collected data of 57 patients (61 hips, 43 female, 18 male) who underwent aseptic acetabular component revision through the DAA with the abovementioned implant system between January 2015 and December 2017. The mean follow-up was 40 months (12-56). Survival rates were estimated using the Kaplan-Meier method. All complications were documented and functional outcomes were assessed pre- and postoperatively. Kaplan-Meier analysis revealed an estimated five-year implant survival of 97\% (confidence interval CI 87-99\%). The estimated five-year survival with revision for any cause was 93\% (CI 83-98\%). The overall revision rate was 6.6\% (n = 4). Two patients had to undergo revision due to periprosthetic infection (3.3\%). In one patient, the acetabular component was revised due to aseptic loosening four months postoperatively. Another patient suffered from postoperative iliopsoas impingement and was treated successfully by arthroscopic iliopsoas tenotomy. Two (3.3\%) of the revised hips dislocated postoperatively. The mean Harris Hip Score improved from 35 (2-66) preoperatively to 86 (38-100) postoperatively (p < 0.001). The hip joint's anatomical center of rotation was restored at a high degree of accuracy. Our findings demonstrate that acetabular revision arthroplasty through the DAA using an asymmetric acetabular component with optional intra- and extramedullary fixation is safe and practicable, resulting in good radiographic and clinical midterm results.},
  language  = {en}
}
@article{ArnholdtKamawalHolzapfeletal.2018,
  author    = {Arnholdt, J{\"o}rg and Kamawal, Yama and Holzapfel, Boris Michael and Ripp, Axel and Rudert, Maximilian and Steinert, Andre Friedrich},
  title     = {Evaluation of implant fit and frontal plane alignment after bi-compartmental knee arthroplasty using patient-specific instruments and implants},
  series = {Archives of Medical Science},
  volume    = {14},
  journal   = {Archives of Medical Science},
  number    = {6},
  doi       = {10.5114/aoms.2018.79007},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-159668},
  pages     = {1424-1431},
  year      = {2018},
  abstract  = {Introduction The goals of successful bi-compartmental knee arthroplasty are to achieve correct fit and positioning of the implant, while appropriately correcting the mechanical alignment of the leg after surgery. As these requirements are not always reliably fulfilled using off-the-shelf implant systems, newer approaches for bi-compartmental resurfacing have been explored. Material and methods In this article we report the radiographic results of 30 patients with anteromedial osteoarthritis (OA) who were treated with a novel patient-specific fixed-bearing bi-compartmental knee resurfacing system using custom-made implants and instruments. Utilizing standardized pre- and postoperative radiographic analyses (based on anterior-posterior and lateral, anterior-posterior weight-bearing full-length radiographs, patella skyline views and preoperative computed tomography (CT) scanning) implant fit and positioning as well as correction of the mechanical axis (hip-knee-ankle angle, HKA) were determined. Results On average, HKA was corrected from 173.4 ±3.47° preoperatively to 179.4 ±2.85° postoperatively. The coronal femoro-tibial angle was corrected on average 5.61°. The preoperative tibial slope measured on lateral views was 6.38 ±2.4°, while the average slope in the CT-based planning protocol (iView) was 6.14 ±2.40°. Postoperative lateral tibial slope was determined to be 5.77 ±1.97°. The thickness of the posterior femoral cuts was measured intraoperatively and, in all cases, corresponded well to the targeted thickness of the cuts provided by the iView. The joint line was preserved in all cases and the average Insall-Salvati index was 1.078 ±0.11 pre- and 1.072 ±0.11 postoperatively. The fit of the implant components measured by over- or underhang was excellent throughout (< 1.01 mm). Conclusions Custom-made bicompartmental knee arthroplasty can ensure optimized fitting and positioning of the implant with restoration of the leg axis. These implants could be considered as an alternative primary solution for knee surgeons treating bi-compartmental disease.},
  language  = {en}
}
@article{BoelchWeissenbergerSpohnetal.2018,
  author    = {Boelch, Sebastian Philipp and Weissenberger, Manuel and Spohn, Frederik and Rudert, Maximilian and Luedemann, Martin},
  title     = {Insufficient sensitivity of joint aspiration during the two-stage exchange of the hip with spacers},
  series = {Journal of Orthopedic Surgery and Research},
  volume    = {13},
  journal   = {Journal of Orthopedic Surgery and Research},
  number    = {7},
  doi       = {10.1186/s13018-017-0703-z},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-175576},
  year      = {2018},
  abstract  = {Background: Evaluation of infection persistence during the two-stage exchange of the hip is challenging. Joint aspiration before reconstruction is supposed to rule out infection persistence. Sensitivity and specificity of synovial fluid culture and synovial leucocyte count for detecting infection persistence during the two-stage exchange of the hip were evaluated. Methods: Ninety-two aspirations before planned joint reconstruction during the two-stage exchange with spacers of the hip were retrospectively analyzed. Results: The sensitivity and specificity of synovial fluid culture was 4.6 and 94.3\%. The sensitivity and specificity of synovial leucocyte count at a cut-off value of 2000 cells/μl was 25.0 and 96.9\%. C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) values were significantly higher before prosthesis removal and reconstruction or spacer exchange (p = 0.00; p = 0.013 and p = 0.039; p = 0.002) in the infection persistence group. Receiver operating characteristic area under the curve values before prosthesis removal and reconstruction or spacer exchange for ESR were lower (0.516 and 0.635) than for CRP (0.720 and 0.671). Conclusions: Synovial fluid culture and leucocyte count cannot rule out infection persistence during the two-stage exchange of the hip.},
  language  = {en}
}
@article{BoelchRuecklFuchsetal.2018,
  author    = {Boelch, Sebastian P. and Rueckl, Kilian and Fuchs, Clara and Jordan, Martin and Knauer, Markus and Steinert, Andre and Rudert, Maximilian and Luedemann, Martin},
  title     = {Comparison of elution characteristics and compressive strength of biantibiotic-loaded PMMA bone cement for spacers: Copal\(^®\) spacem with gentamicin and vancomycin versus Palacos\(^®\) R+G with vancomycin},
  series = {BioMed Research International},
  volume    = {2018},
  journal   = {BioMed Research International},
  number    = {4323518},
  doi       = {10.1155/2018/4323518},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-177435},
  year      = {2018},
  abstract  = {Purpose. Copal\(^®\) spacem is a new PMMA bone cement for fabricating spacers. This study compares elution of gentamicin, elution of vancomycin, and compressive strength of Copal\(^®\) spacem and of Palacos\(^®\) R+G at different vancomycin loadings in the powder of the cements. We hypothesized that antibiotic elution of Copal\(^®\) spacem is superior at comparable compressive strength. Methods. Compression test specimens were fabricated using Copal\(^®\) spacem manually loaded with 0.5 g gentamicin and additionally 2 g, 4 g, and 6 g of vancomycin per 40 g of cement powder (COP specimens) and using 0.5 g gentamicin premixed Palacos\(^®\) R+G manually loaded with 2 g, 4 g, and 6 g of vancomycin per 40 g of cement powder (PAL specimens). These specimens were used for determination of gentamicin and vancomycin elution (in fetal calf serum, at 22°C) and for determination of compressive strength both prior and following the elution tests. Results. Cumulative gentamicin concentrations (p < 0.005) and gentamicin concentration after 28 days (p ≤ 0.043) were significantly lower for COP specimens compared to PAL specimens. Cumulative vancomycin concentrations were significantly higher (p ≤ 0.043) for COP specimens after the second day. Vancomycin concentrations after 28 days were not significantly higher for the Copal specimens loaded with 2 g and 4 g of vancomycin. Compressive strength was not significantly different between COP specimens and PAL specimens before elution tests. Compressive strength after the elution tests was significantly lower (p = 0.005) for COP specimens loaded with 2 g of vancomycin. Conclusion. We could not demonstrate consistent superior antibiotic elution from Copal\(^®\) spacem compared to Palacos\(^®\) R+G for fabricating gentamicin and vancomycin loaded spacers. The results do not favor Copal\(^®\) spacem over Palacos\(^®\) R+G for the use as a gentamicin and vancomycin biantibiotic-loaded spacer.},
  language  = {en}
}
@article{ReichertvonRottkayRothetal.2018,
  author    = {Reichert, Johannes C. and von Rottkay, Eberhard and Roth, Franz and Renz, Tim and Hausmann, Johannes and Kranz, Julius and Rackwitz, Lars and N{\"o}th, Ulrich and Rudert, Maximilian},
  title     = {A prospective randomized comparison of the minimally invasive direct anterior and the transgluteal approach for primary total hip arthroplasty},
  series = {BMC Musculoskeletal Disorders},
  volume    = {19},
  journal   = {BMC Musculoskeletal Disorders},
  number    = {241},
  doi       = {10.1186/s12891-018-2133-4},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176072},
  year      = {2018},
  abstract  = {Background: The presented prospective randomized controlled single-centre study compares the clinical outcome up to 12 months after total hip arthroplasty using a minimally invasive single-incision direct anterior (DAA) and a direct transgluteal lateral approach. Methods: A total of 123 arthroplasties were evaluated utilizing the Harris Hip Score (HHS), the extra short musculoskeletal functional assessment questionnaire (XSFMA), the Short Form 36 (SF-36) health survey, a Stepwatch™ Activity Monitor (SAM), and a timed 25 m foot walk (T25-FW). Postoperative x-ray images after THA were reviewed to determine inclination and stem positioning. Results: At final follow-up, the XSFMA functional index scores were 10.3 (anterior) and 15.08 (lateral) while the bother index summed up to a score of 15.8 (anterior) and 21.66 (lateral) respectively, thus only differing significantly for the functional index (p = 0.040 and p = 0.056). The SF-36 physical component score (PCS) was 47.49 (anterior) and 42.91 (lateral) while the mental component score (MCS) summed up to 55.0 (anterior) and 56.23 (lateral) with a significant difference evident for the PCS (p = 0.017; p = 0.714). Patients undergoing THA through a DAA undertook a mean of 6402 cycles per day while those who had undergone THA through a transgluteal approach undertook a mean of 5340 cycles per day (p = 0.012). Furthermore, the obtained outcome for the T25-FW with 18.4 s (anterior) and 19.75 s (lateral) and the maximum walking distance (5932 m and 5125 m) differed significantly (p = 0.046 and p = 0.045). The average HHS showed no significant difference equaling 92.4 points in the anterior group and 91.43 in the lateral group (p = 0.477). The radiographic analysis revealed an average cup inclination of 38.6° (anterior) and 40.28° (lateral) without signs of migration. Conclusion: In summary, our outcomes show that after 1 year THA through the direct anterior approach results in a higher patient activity compared to THA utilizing a transgluteal lateral approach while no differences regarding hip function are evident.},
  language  = {en}
}
@article{BoelchRothArnholdtetal.2018,
  author    = {Boelch, Sebastian P. and Roth, Magnus and Arnholdt, Joerg and Rudert, Maximilian and Luedemann, Martin},
  title     = {Synovial fluid aspiration should not be routinely performed during the two-stage exchange of the knee},
  series = {BioMed Research International},
  volume    = {2018},
  journal   = {BioMed Research International},
  number    = {6720712},
  doi       = {10.1155/2018/6720712},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176800},
  year      = {2018},
  abstract  = {Purpose. Detection of infection persistence during the two-stage exchange of the knee for periprosthetic joint infection is challenging. Synovial fluid culture (SFC) and synovial white blood cell count (SWBCC) before joint reimplantation are widespread diagnostic means for this indication. The sensitivity and specificity of SFC and of SWBCC for infection persistence before planned reimplantation were evaluated. Methods. 94 two-stage exchanges of the knee with synovial fluid aspiration performed after a drug holiday of at least 14 days and before reimplantation or spacer exchange (planned reimplantation) were retrospectively analyzed. Only cases with at least 3 intraoperative samples at planned reimplantation were included. SFC and SWBCC were compared to pathogen detection (SFC\(_{(culture)}\)/SWBCC\(_{(culture)}\) and to histopathological signs of infection persistence (SFC\(_{(histo)}\)/SWBCC\(_{(histo)}\) from intraoperative samples at planned reimplantation. For SFC, the sensitivity and specificity were calculated. For SWBCC, the optimal cut-off value with its sensitivity and specificity was calculated with the Youden-Index. Results. Sensitivity and specificity of SFC\(_{(culture)}\) were 0.0\% and 98.9\%. Sensitivity and specificity of SFC\(_{(histo)}\) were 3.4\% and 100\%. The optimal cut-off value for SWBCC\(_{(culture)}\) was 4450 cells/μl with a sensitivity of 50.0\% and a specificity of 86.5\%. The optimal cut-off value for SWBCC\(_{(histo)}\) was 3250 cells/μl with a sensitivity of 35.7\% and a specificity of 92.9\%. Conclusion. The detection of infection persistence remains challenging and a consented approach is lacking. The results do not warrant the routine performance of SFC during the two-stage exchange at the knee. SWBCC can be used to confirm infection persistence at high cut-offs, but they only occur in few patients and are therefore inappropriate for the routine use.},
  language  = {en}
}
@article{ArnholdtGilbertBlanketal.2017,
  author    = {Arnholdt, J{\"o}rg and Gilbert, Fabian and Blank, Marc and Papazoglou, Jannis and Rudert, Maximilian and N{\"o}th, Ulrich and Steinert, Andre F.},
  title     = {The Mayo conservative hip: complication analysis and management of the first 41 cases performed at a University level 1 department},
  series = {BMC Muskoskeletal Disorders},
  volume    = {18},
  journal   = {BMC Muskoskeletal Disorders},
  number    = {250},
  doi       = {10.1186/s12891-017-1613-2},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-157812},
  year      = {2017},
  abstract  = {Background: To prevent bone loss in hip arthroplasty, several short stem systems have been developed, including the Mayo conservative hip system. While there is a plethora of data confirming inherent advantages of these systems, only little is known about potential complications, especially when surgeons start to use these systems. Methods: In this study, we present a retrospective analysis of the patients' outcome, complications and the complication management of the first 41 Mayo conservative hips performed in 37 patients. For this reason, functional scores, radiographic analyses, peri- and postoperative complications were assessed at an average follow-up of 35 months. Results: The overall HHS improved from 61.2 pre-operatively to 85.6 post-operatively. The German Extra Short Musculoskeletal Function Assessment Questionnaire (XSFMA-D) improved from 30.3 pre-operatively to 12.2 post-operatively. The most common complication was an intraoperative non-displaced fracture of the proximal femur observed in 5 cases (12.1\%). Diabetes, higher BMI and older ages were shown to be risk factors for these intra-operative periprosthetic fractures (p < 0.01). Radiographic analysis revealed a good offset reconstruction in all cases. Conclusion: In our series, a high complication rate with 12.1\% of non-displaced proximal femoral fractures was observed using the Mayo conservative hip. This may be attributed to the flat learning curve of the system or the inherent patient characteristics of the presented cohort."},
  language  = {en}
}
@article{KamawalSteinertHolzapfeletal.2016,
  author    = {Kamawal, Yama and Steinert, Andre F and Holzapfel, Boris M and Rudert, Maximilian and Barthel, Thomas},
  title     = {Case report - calcification of the medial collateral ligament of the knee with simultaneous calcifying tendinitis of the rotator cuff},
  series = {BMC Muscoskeletal Disorders},
  volume    = {17},
  journal   = {BMC Muscoskeletal Disorders},
  number    = {283},
  doi       = {10.1186/s12891-016-1147-z},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-147669},
  year      = {2016},
  abstract  = {Calcification of the medial collateral ligament (MCL) of the knee is a very rare disease. We report on a case of a patient with a calcifying lesion within the MCL and simultaneous calcifying tendinitis of the rotator cuff in both shoulders. Case presentation: Calcification of the MCL was diagnosed both via x-ray and magnetic resonance imaging (MRI) and was successfully treated surgically. Calcifying tendinitis of the rotator cuff was successfully treated applying conservative methods. Conclusion: This is the first case report of a patient suffering from both a calcifying lesion within the medial collateral ligament and calcifying tendinitis of the rotator cuff in both shoulders. Clinical symptoms, radio-morphological characteristics and macroscopic features were very similar and therefore it can be postulated that the underlying pathophysiology is the same in both diseases. Our experience suggests that magnetic resonance imaging and x-ray are invaluable tools for the diagnosis of this inflammatory calcifying disease of the ligament, and that surgical repair provides a good outcome if conservative treatment fails. It seems that calcification of the MCL is more likely to require surgery than calcifying tendinitis of the rotator cuff. However, the exact reason for this remains unclear to date.},
  language  = {en}
}
@article{RudertHorasHobergetal.2016,
  author    = {Rudert, Maximilian and Horas, Konstantin and Hoberg, Maik and Steinert, Andre and Holzapfel, Dominik Emanuel and H{\"u}bner, Stefan and Holzapfel, Boris Michael},
  title     = {The Wuerzburg procedure: the tensor fasciae latae perforator is a reliable anatomical landmark to clearly identify the Hueter interval when using the minimally-invasive direct anterior approach to the hip joint},
  series = {BMC Musculoskeletal Disorders},
  volume    = {17},
  journal   = {BMC Musculoskeletal Disorders},
  number    = {57},
  doi       = {10.1186/s12891-016-0908-z},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146031},
  year      = {2016},
  abstract  = {Background The key for successful delivery in minimally-invasive hip replacement lies in the exact knowledge about the surgical anatomy. The minimally-invasive direct anterior approach to the hip joint makes it necessary to clearly identify the tensor fasciae latae muscle in order to enter the Hueter interval without damaging the lateral femoral cutaneous nerve. However, due to the inherently restricted overview in minimally-invasive surgery, this can be difficult even for experienced surgeons. Methods and Surgical Technique In this technical note, we demonstrate for the first time how to use the tensor fasciae latae perforator as anatomical landmark to reliably identify the tensor fasciae latae muscle in orthopaedic surgery. Such perforators are used for flaps in plastic surgery as they are constant and can be found at the lateral third of the tensor fasciae latae muscle in a direct line from the anterior superior iliac spine. Conclusion As demonstrated in this article, a simple knowledge transfer between surgical disciplines can minimize the complication rate associated with minimally-invasive hip replacement.},
  language  = {en}
}
@article{BoelchBarthelGoebeletal.2015,
  author    = {Boelch, Sebastian Philipp and Barthel, Thomas and Goebel, Sascha and Rudert, Maximilian and Plumhoff, Piet},
  title     = {Calcinosis universalis - a rare case with classical presentation},
  series = {Case Reports in Orthopedics},
  volume    = {2015},
  journal   = {Case Reports in Orthopedics},
  doi       = {10.1155/2015/505420},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-126300},
  pages     = {505420},
  year      = {2015},
  abstract  = {Juvenile Dermatomyositis (JDM) is a rare autoimmune disease in children and adolescents. In these patients calcinosis might be the most characteristic symptom. However there are only few reported cases of intramuscular calcinosis in Dermatomyositis. We report a case of calcinosis universalis (CU) of the elbow in JDM successfully treated with broaching. The patient, a 24-year-old woman, suffered from a long history of JDM. On examination she presented with a fistula lateral to the olecranon and pain of the right elbow joint. Plain X-rays displayed a diffuse pattern of multiple periarticular, subcutaneous, and intramuscular calcifications. The patient underwent surgery for histological and microbiological sampling as well as broaching. Intraoperatively sinus formation and subfascial hard calcium deposition were found. Due to the risk of collateral tissue damage, incomplete broaching was performed. A local infection with Staphylococcus was diagnosed and treated with antibiotics. On six-week and 30-month follow-up the patient was free of pain and had very good function. Calcifications on standard radiographs had almost resolved entirely. This case report gives a summary on calcinosis in Dermatomyositis and adds a new case of recalcitrant CU to the literature. Broaching surgery proved to be a reliable treatment option in symptomatic calcinosis.},
  language  = {en}
}
@article{RudertHolzapfelJakubietz2011,
  author    = {Rudert, Maximilian and Holzapfel, Boris Michael and Jakubietz, Michael},
  title     = {Adjuvant Radiotherapy},
  series = {Deutsches {\"A}rzteblatt International},
  volume    = {108},
  journal   = {Deutsches {\"A}rzteblatt International},
  number    = {33},
  doi       = {10.3238/arztebl.2011.0553a},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133571},
  pages     = {553},
  year      = {2011},
  abstract  = {No abstract available.},
  language  = {en}
}