TY - JOUR A1 - Boelch, Sebastian P. A1 - Rueckl, Kilian A1 - Fuchs, Clara A1 - Jordan, Martin A1 - Knauer, Markus A1 - Steinert, Andre A1 - Rudert, Maximilian A1 - Luedemann, Martin T1 - 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 JF - BioMed Research International N2 - 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. KW - Copal\(^®\) spacem KW - PMMA bone cement KW - elution KW - compressive strength Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-177435 VL - 2018 IS - 4323518 ER - TY - JOUR A1 - Arnholdt, Jörg A1 - Gilbert, Fabian A1 - Blank, Marc A1 - Papazoglou, Jannis A1 - Rudert, Maximilian A1 - Nöth, Ulrich A1 - Steinert, Andre F. T1 - The Mayo conservative hip: complication analysis and management of the first 41 cases performed at a University level 1 department JF - BMC Muskoskeletal Disorders N2 - 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." KW - total hip arthroplasty KW - short hip stem KW - mayo stem KW - minimal invasive surgery Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-157812 VL - 18 IS - 250 ER - TY - JOUR A1 - Kamawal, Yama A1 - Steinert, Andre F A1 - Holzapfel, Boris M A1 - Rudert, Maximilian A1 - Barthel, Thomas T1 - Case report - calcification of the medial collateral ligament of the knee with simultaneous calcifying tendinitis of the rotator cuff JF - BMC Muscoskeletal Disorders N2 - 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. KW - case report KW - calcification KW - medical collateral ligament KW - knee rotator cuff KW - open surgical repair Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-147669 VL - 17 IS - 283 ER - TY - JOUR A1 - Rudert, Maximilian A1 - Horas, Konstantin A1 - Hoberg, Maik A1 - Steinert, Andre A1 - Holzapfel, Dominik Emanuel A1 - Hübner, Stefan A1 - Holzapfel, Boris Michael T1 - 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 JF - BMC Musculoskeletal Disorders N2 - 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. KW - anatomical landmark KW - direct anterior approach KW - Hueter interval KW - minimally-invasive KW - hip replacement KW - perforator Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146031 VL - 17 IS - 57 ER - TY - JOUR A1 - Boelch, Sebastian Philipp A1 - Barthel, Thomas A1 - Goebel, Sascha A1 - Rudert, Maximilian A1 - Plumhoff, Piet T1 - Calcinosis universalis - a rare case with classical presentation JF - Case Reports in Orthopedics N2 - 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. Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126300 VL - 2015 ER - TY - JOUR A1 - Rudert, Maximilian A1 - Holzapfel, Boris Michael A1 - Jakubietz, Michael T1 - Adjuvant Radiotherapy JF - Deutsches Ärzteblatt International N2 - No abstract available. KW - Soft-tissue sarcoma Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-133571 VL - 108 IS - 33 ER -