@phdthesis{Doerries2020,
  author    = {D{\"o}rries, Susanne},
  title     = {Analyse der Gr{\"u}nde f{\"u}r Revisionsoperationen bei einliegender Knieprothese},
  doi       = {10.25972/OPUS-21403},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-214034},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2020},
  abstract  = {Die Knieendoprothetik verzeichnet in den letzten Jahren steigende Zahlen, was wiederum steigende Zahlen an Revisionen zur Folge hat. Diese Studie hat die Gr{\"u}nde f{\"u}r Revisionen ermittelt. Hierzu wurden 1245 Operationen gesammelt und ausgewertet. Instabilit{\"a}t, Infektion und aseptische Lockerungen stellen die Hauptgr{\"u}nde f{\"u}r eine Revisionsoperation dar. Es wurden zus{\"a}tzlich verschiedene Zeitr{\"a}ume zwischen Prim{\"a}rimplantation und Revision unterteilt und die jeweiligen Gr{\"u}nde ermittelt.},
  subject      = {Reoperation},
  language  = {de}
}
@phdthesis{Bischof2006,
  author    = {Bischof, Antje},
  title     = {Ergebnisse der Knieendoprothetik bei M. Ahlb{\"a}ck : Unikondyl{\"a}re versus Bikondyl{\"a}re Prothese},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-20957},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2006},
  abstract  = {Die vorliegende Studie berichtet erstmals {\"u}ber den Vergleich einer uni- mit einer bikondyl{\"a}ren Endoprothese zur Therapie des M. Ahlb{\"a}ck im Sp{\"a}tstadium. Da diese Osteonekrose nur das mediale Kompartiment betrifft, liegt die Indikation f{\"u}r eine unikompartimentelle Prothese vor. Trotzdem wurde entsprechend den Erfahrungen der Operateure in unserer Klinik seit 1988 h{\"a}ufiger eine bikondyl{\"a}re Prothese inmplantiert. In der der Literatur findet sich bis heute keine einheitliche Meineung zu diesem Thema und es gibt nur wenige Studien zum M. Ahlb{\"a}ck, da diese Erkrankung sehr selten auftritt. Daher wurde diese Studie konzipiert, mit dem Ziel, die Ergebnisse der unikondyl{\"a}ren gegen{\"u}ber der bikondyl{\"a}ren Prothese zu vergleichen. In diese Studie wurden 37 Patienten (39 Knie) mit der Diagnose M. Ahlb{\"a}ck eingeschlossen. Die pr{\"a}- und intraoperativen klinischen und r{\"o}ntgenologisch Daten wurden retrospektiv erfaßt. Daraufhin wurden die Patienten bei einem Follow up nach durchschnitllich 6,6 (0,75-16,75) Jahren nochmals klinisch und r{\"o}ntgenologisch untersucht. Aufgrund der geringen Inzidenz des M. Ahlb{\"a}ck war die Studie auf eine kleine Fallzahl beschr{\"a}nkt. Zusammenfassend kann gesagt werden, daß in allen klinischen und r{\"o}ntgenologischen Beobachtungen sowie in der Analyse der berechneten Scores die bikondyl{\"a}re Prothese der unikondyl{\"a}ren {\"u}berlegen war. Die Verankerung der unikondyl{\"a}ren Prothese im femoralen Knochenlager scheint aufgrund der Nekrosezone beim M. Ahlb{\"a}ck nicht ausreichend gew{\"a}hrleistet zu sein. Daher empfehlen wir die bevorzugte Implantation einer bikondyl{\"a}ren Prothese gegen{\"u}ber einem unikondyl{\"a}ren Modell f{\"u}r die operative Therapie des M. Ahlb{\"a}ck.},
  language  = {de}
}
@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{RakKlannHeinzetal.2023,
  author    = {Rak, Dominik and Klann, Lukas and Heinz, Tizian and Anderson, Philip and Stratos, Ioannis and Nedopil, Alexander J. and Rudert, Maximilian},
  title     = {Influence of mechanical alignment on functional knee phenotypes and clinical outcomes in primary TKA: a 1-year prospective analysis},
  series = {Journal of Personalized Medicine},
  volume    = {13},
  journal   = {Journal of Personalized Medicine},
  number    = {5},
  issn      = {2075-4426},
  doi       = {10.3390/jpm13050778},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-313646},
  year      = {2023},
  abstract  = {In total knee arthroplasty (TKA), functional knee phenotypes are of interest regarding surgical alignment strategies. Functional knee phenotypes were introduced in 2019 and consist of limb, femoral, and tibial phenotypes. The hypothesis of this study was that mechanically aligned (MA) TKA changes preoperative functional phenotypes, which decreases the 1-year Forgotten Joint (FJS) and Oxford Knee Score (OKS) and increases the 1-year WOMAC. All patients included in this study had end-stage osteoarthritis and were treated with a primary MA TKA, which was supervised by four academic knee arthroplasty specialists. To determine the limb, femoral, and tibial phenotype, a long-leg radiograph (LLR) was imaged preoperatively and two to three days after TKA. FJS, OKS, and WOMAC were obtained 1 year after TKA. Patients were categorized using the change in functional limb, femoral, and tibial phenotype measured on LLR, and the scores were compared between the different categories. A complete dataset of preoperative and postoperative scores and radiographic images could be obtained for 59 patients. 42\% of these patients had a change of limb phenotype, 41\% a change of femoral phenotype, and 24\% a change of tibial phenotype of more than ±1 relative to the preoperative phenotype. Patients with more than ±1 change of limb phenotype had significantly lower median FJS (27 points) and OKS (31 points) and higher WOMAC scores (30 points) relative to the 59-, 41-, and 4-point scores of those with a 0 ± 1 change (p < 0.0001 to 0.0048). Patients with a more than ±1 change of femoral phenotype had significantly lower median FJS (28 points) and OKS (32 points) and higher WOMAC scores (24 points) relative to the 69-, 40-, and 8-point scores of those with a 0 ± 1 change (p < 0.0001). A change in tibial phenotype had no effect on the FJS, OKS, and WOMAC scores. Surgeons performing MA TKA could consider limiting coronal alignment corrections of the limb and femoral joint line to within one phenotype to reduce the risk of low patient-reported satisfaction and function at 1-year.},
  language  = {en}
}
@article{BoelchJakuscheitDoerriesetal.2018,
  author    = {Boelch, S. P. and Jakuscheit, A. and Doerries, S. and Fraissler, L. and Hoberg, M. and Arnholdt, J. and Rudert, M.},
  title     = {Periprosthetic infection is the major indication for TKA revision - experiences from a university referral arthroplasty center},
  series = {BMC Musculoskeletal Disorders},
  volume    = {19},
  journal   = {BMC Musculoskeletal Disorders},
  number    = {395},
  doi       = {10.1186/s12891-018-2314-1},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176983},
  year      = {2018},
  abstract  = {Background: We hypothesized, that periprosthetic joint infection (PJI) accounts for the major proportion of first (primary) and repeated (secondary) Total Knee Arthroplasty revisions at our university referral arthroplasty center. Methods: One thousand one hundred forty-three revisions, performed between 2008 and 2016 were grouped into primary (55\%) and secondary (45\%) revisions. The rate of revision indications was calculated and indications were categorized by time after index operation. The odds ratios of the indications for primary versus secondary revision were calculated. Results: In the primary revision group PJI accounted for 22.3\%, instability for 20.0\%, aseptic loosening for 14.9\% and retropatellar arthrosis for 14.2\%. PJI (25.6\%) was the most common indication up to 1 year after implantation, retropatellar arthrosis (26.8\%) 1-3 years and aseptic loosening (25.6\%) more than 3 years after implantation. In the secondary revision group PJI accounted for 39.7\%, aseptic loosening for 16.2\% and instability for 13.2\%. PJI was the most common indication at any time of revision with 43.8\% up to one, 35.4\% 1-3 years and 39.4\% more the 3 years after index operation. The odds ratios in repeated revision were 2.32 times higher (p = 0.000) for PJI. For instability and retropatellar arthrosis the odds ratios were 0.60 times (p = 0.006) and 0.22 times (p = 0.000) lower. Conclusions: PJI is the most common indication for secondary TKA revision and within one year after primary TKA. Aseptical failures such as instability, retropatellar arthrosis and aseptical loosening are the predominant reasons for revision more than one year after primary TKA.},
  language  = {en}
}