S Gravius

University of Bonn, Bonn, North Rhine-Westphalia, Germany

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Publications (113)146.82 Total impact

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    ABSTRACT: Revision of failed total hip arthroplasty with severe acetabular bone loss represents a rare but challenging problem. Anatomic reconstruction with biological defect augmentation as solid bone transplants or cancellous bone restores bone stock while providing good component stability. The objective of this study was to present short- to mid-term results of revision total hip arthroplasty with a modular ring system in a consecutive series of patients with severe acetabular bone loss.
    International Orthopaedics 10/2014; · 2.32 Impact Factor
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    ABSTRACT: The accurate diagnosis of periprosthetic joint infection (PJI) relies on clinical investigation, laboratory parameters, radiological methods, sterile joint aspiration for synovial fluid leucocyte count and microbiological analysis and tissue sampling for histopathology. Due to the limits in specificity and sensitivity of these methods, molecular techniques and new biomarkers were introduced into the diagnostic procedure. Histological examination is related to the amount of neutrophils in the periprosthetic tissue in frozen sections and formalin-fixed paraffin embedded material (FFPE). However, the threshold of neutrophils per defined area of tissue among various studies is very inconsistent.
    International Orthopaedics 10/2014; · 2.32 Impact Factor
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    ABSTRACT: Background: Conventional uncemented femoral stems provide good long-term fixation in patients with a wide range of clinical function. However, preservation of bone stock, and minimally invasive approaches have led to exploration into various other implant designs. Short-stem prosthesis focusing on a stable metaphyseal fit have emerged to address these challenges in total hip arthroplasty. The purpose of this study was to evaluate the clinical and radiological results of a newly developed short-stem hip prosthesis AIDA® in context of a single surgeon study. Material and Methods: From February 2009 to December 2013, 72 cementless "AIDA® short stems" (Fa. Implantcast) were implanted by a single surgeon in one study centre via the Watson Jones interval. All patients signed informed consent prior to screening and the study design was approved by the local ethics committee. 51 patients with 52 implants (35 female, 36 male) with a follow-up > 24 months were included in this prospective, controlled clinical trial. The patients were pre- and postoperatively examined clinically and radiological by a specified protocol. Results: The average patient age at the time of THA was 61 ± 3.2 years (min.-max. 46-68 years). At the last follow-up, the average Harris Hip score increased from 41.4 ± 4.5 preoperatively to 96.8 ± 3.2 points postoperatively. The hospital stay was 9.1 days on average. The X-rays showed in all cases a stable fixation of the stems with full bony integration and no signs of loosening or migration. There were no specific complications relating to the less invasive approach. Postoperatively one periprosthetic fracture was evident. The revision operation into a cementless stem was done without any complications (revisions rate 1.9 %). Conclusion: The newly developed "AIDA short stem" is a promising hip implant for the young and active patient with osteoarthritis of the hip. The short-term results are encouraging, but nevertheless mid- and long-term results must be further observed on a prospective basis as part of this collective study.
    Zeitschrift fur Orthopadie und Unfallchirurgie 10/2014; 152(5):504-509. · 0.65 Impact Factor
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    ABSTRACT: Background and purpose — Due to the relative lack of reports on the medium- to long-term clinical and radiographic results of modular femoral cementless revision, we conducted this study to evaluate the medium- to long-term results of uncemented femoral stem revisions using the modular MRP-TITAN stem with distal diaphyseal fixation in a consecutive patient series. Patients and methods — We retrospectively analyzed 163 femoral stem revisions performed between 1993 and 2001 with a mean follow-up of 10 (5–16) years. Clinical assessment included the Harris hip score (HHS) with reference to comorbidities and femoral defect sizes classified by Charnley and Paprosky. Intraoperative and postoperative complications were analyzed and the failure rate of the MRP stem for any reason was examined. Results — Mean HHS improved up to the last follow-up (37 (SD 24) vs. 79 (SD 19); p < 0.001). 99 cases (61%) had extensive bone defects (Paprosky IIB–III). Radiographic evaluation showed stable stem anchorage in 151 cases (93%) at the last follow-up. 10 implants (6%) failed for various reasons. Neither a breakage of a stem nor loosening of the morse taper junction was recorded. Kaplan-Meier survival analysis revealed a 10-year survival probability of 97% (95% CI: 95–100). Interpretation — This is one of the largest medium- to long-term analyses of cementless modular revision stems with distal diaphyseal anchorage. The modular MRP-TITAN was reliable, with a Kaplan-Meier survival probability of 97% at 10 years.
    Acta Orthopaedica. 09/2014;
  • T M Randau, S Gravius, A Nüssler
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    ABSTRACT: Over the last few years, numerous new treatment methods have been developed for musculoskeletal diseases. Some of these new methods are based on the targeted use of stem cells to initiate healing processes, to compensate for deficits or to activate the regeneration of tendons, muscles, bones and cartilage. This goal can be achieved through the direct use of stem cells on or in a carrier material or through a combination with tissue engineering. In this article, we give a short overview of the possible fields of application of inducible pluripotent haematopoietic, and adult stem cells as well as on their use in musculoskeletal tissue. Furthermore, we provide a summary of the current legal situation concerning the application of stem cells in humans.
    Zeitschrift fur Orthopadie und Unfallchirurgie 08/2014; 152(4):320-327. · 0.65 Impact Factor
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    ABSTRACT: In Germany, 800,000 fractures are treated per year, and up to 10 % of these patients may suffer subsequently from a delayed union or a nonunion at the fracture site. Surgical treatment of these complications is tedious and associated with high costs. Therefore non-operative treatment is recently receiving more scientific and clinical attention. The adjuvant treatment with ultrasound has been propagated for the past years to enhance fracture healing and bony union, and has been discussed controversially. This review article demonstrates the significance of the low intensity pulsed ultrasound application in fracture treatment, on the basis of basic science results, animal experiments and the results of clinical trials.
    Zeitschrift fur Orthopadie und Unfallchirurgie 07/2014; · 0.65 Impact Factor
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    ABSTRACT: Acinetobacter baumannii is an emerging nosocomial pathogen primarily in countries with a high prevalence of multidrug resistance. Here we report the detection of a bla OXA23 carbapenemase-producing A. baumannii strain in a German patient with prosthetic hip joint infection following several hip joint surgeries but no history of foreign travel.
    Infection 07/2014; · 2.44 Impact Factor
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    ABSTRACT: Revision of failed total hip arthroplasty with massive acetabular bone loss resulting in pelvic discontinuity represents a rare but challenging problem. The objective of this study was to present short to mid-term results of revision total hip arthroplasty with a custom-made acetabular implant in a consecutive series of patients with pelvic discontinuity.
    International Orthopaedics 07/2014; · 2.32 Impact Factor
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    ABSTRACT: The pre-operative differentiation between periprosthetic joint infection (PJI) and aseptic loosening after total hip (THA) or knee (TKA) arthroplasty is essential for successful therapy and relies in part on the use of molecular markers. The objective of this study was to assess serum levels of lipopolysaccharide-binding protein (LBP) as a diagnostic tool for PJI and to compare its accuracy with standard tests. One hundred and twenty patients presenting with a painful TKA or TKA with indication for surgical revision were included in this prospective, controlled, clinical trial at a single centre. Pre-operative blood and serum samples were collected and analysed for white blood cell (WBC) count, C-reactive protein (CRP) and LBP. The definite diagnosis of periprosthetic joint infection was determined on the basis of clinical, microbiological and histopathological examination. LBP showed significantly higher values in PJI compared with aseptic loosening (p < 0.001) and control (p < 0.001), with a specificity of 66 % and a sensitivity of 71 % at a cutoff value of >7 ng/ml. In combination with CRP, the positive predictive value for PJI was at 0.67; negative predictive value with both negative was at 0.77. Patients with PJI have elevated serum levels of LBP when compared with patients with aseptic loosening. The use of LBP in serum appears not to be a more accurate marker than CRP level in serum for detecting PJI. On the basis of these results, we cannot recommend the sole use of LBP for differentiating PJI and aseptic loosening following THA and TKA.
    International Orthopaedics 05/2014; · 2.32 Impact Factor
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    ABSTRACT: Arthropathy as a result of repeated joint bleeding is a severe complication in patients with haemophilia. In the evaluation of synovial tissue specimens, histology alone is non-specific and there is considerable morphological overlap with other joint diseases. Formalin-fixed paraffin-embedded specimens are available in pathological institutes and can be studied to understand the pathogenesis of haemophilic arthropathy. A powerful technique to identify hundreds of proteins in a tissue section combining proteomics with morphology is imaging mass spectrometry (IMS). We determined whether matrix-assisted laser desorption/ionization (MALDI) IMS can be used to identify and map protein signatures in the synovial tissue of patients with haemophilic arthropathy. MALDI IMS was applied to synovial tissue of six patients with haemophilic arthropathy. We detected several peaks predictive in mass with ferritin light (m/z 1608) and heavy chain (m/z 1345), alpha- (m/z 1071) and beta (m/z 1274) haemoglobin subunits, truncated coagulation factor VIII peptide (m/z 1502, 1176), beta- and gamma fibrinogen peptides (m/z 980, 1032, 1117 and 1683), and annexin A2 (m/z 1111, 1268, 1460, 2164). In addition, the distribution of these proteins in synovial tissue sections was demonstrated. MALDI IMS identified and mapped specific proteins in the synovial membrane of patients with haemophilic arthropathy known to be involved in the pathogenesis of other joint diseases. This technique is a powerful tool to analyse the distribution of proteins in synovial tissue sections.
    Haemophilia 05/2014; 20(3):446-53. · 3.17 Impact Factor
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    ABSTRACT: Management of acetabular bone defects Paprosky types IIa and IIb in revision hip arthroplasty by rebuilding the bone stock using impaction bone grafting, primary stable reconstruction with an acetabular reconstruction ring, and restoring the hip center of rotation to its anatomical position. Acetabular segmental or combined structural defects in the superior acetabular dome with superior/lateral hip center migration with intact anterior and posterior columns (Paprosky types IIa, IIb). Acute or chronic infections, severe acetabular bone defects preventing adequate anchorage of the prosthesis-particularly destruction of the posterior column. Modified transgluteal, lateral approach to the hip joint. Removal of the loose acetabular component. Complete circumferential exposure of the acetabular rim, while maintaining mechanical stability of the remaining bone. Preparation of the homologous spongiosa chips and reconstruction of the acetabular defect in impaction grafting technique. Implantation of the acetabular reconstruction ring and primary stable fixation with cancellous screws in the acetabular dome. Cemented fixation of a polyethylene inlay. Mobilization on 2 underarm crutches from postoperative day 1. Partial weight bearing with 20 kg for 6 weeks postoperatively. If plain radiographs show unchanged seating of the prosthesis after 6 weeks, loading can be increased by 10 kg/week until full weight bearing is achieved; thrombosis prophylaxis is continued throughout. Limitation of hip flexion to 90° during the first 6 weeks, and no adduction and forced external rotation to avoid dislocation. Avoidance of sports involving jumping and axial impact loading for 12 months. Radiologic checkups after 3, 6, and 12 months and, thereafter, every 2 years. Analysis between 2008 and 2011 involved 22 consecutive patients with a total of 23 prostheses; the mean follow-up was 38 ± 11 months. Compared to the preoperative evaluation, follow-up yielded a significant improvement in the average Harris Hip Score (82.2 ± 8.7 vs. 44.7 ± 10.7) and the Merle d'Aubigné Score (14.6 ± 1.9 vs. 7.5 ± 1.3). Radiological solid osseointegration of the cup was observed in 21 cases; partial radiolucent lines were seen in 2 cases (9 %) in the zones I-III delineated by DeLee and Charnley. In 21 cases (91 %) radiographs confirmed no measurable migration or displacement of the acetabular component and the bone graft was determined to be incorporated on the basis of osseous consolidation within the grafted area in 20 cases (87 %). During follow-up 3 prosthesis (13 %) required revision.
    Operative Orthopädie und Traumatologie 04/2014; · 0.47 Impact Factor
  • J Schmolders, S Gravius, D C Wirtz
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    ABSTRACT: Introduction: Minimally invasive approaches to the hip joint during primary endoprosthetics have been for many years the focus of controversial discussion. Minimally invasive approaches offer soft tissue protecting implantations clear advantages regarding early postoperative functional results and reduced intraoperative blood loss. Method: On the basis of comprising literary research the available primary and secondary literature is evaluated - the advantages and disadvantages of minimally invasive approaches at the hip joint are discussed in relation to traditional approaches. Results: The available primary and secondary literature verifies that the advantages of minimally invasive approaches at the hip joint include functional outcome in the early postoperative phase. In comparison to standard approaches there are no differences in the functional outcome after 12 months follow-up. Additionally, reduced length of operation, reduced blood loss and shorter stationary stay are confirmed. Studies relating to degrees of evidence I and II, which concern the medium- and long-term results of minimally invasive approaches in comparison to the established standard approaches, are not available. The available systematic reviews and meta-analyses merely allow a global evaluation of the primary literature on minimally invasive approaches, without thereby differentiating between the established standard approaches and the modified pendant according to minimally invasive criteria. There is a lack of knowledge with regard to in-vivo imaging data (MRI) as a potential evidence for reduction of muscular trauma by using minimally invasive approaches. Conclusion: Presently, the available literature does not allow definitive assessment regarding the significance of minimally invasive approaches at the hip joint. Future, random-controlled studies are necessary in order to compare the reliable (long-term) results of the established standard approaches with the hip approaches according to minimally invasive criteria. As long as sufficient long-term results regarding the complication and revision rates of minimally invasive approaches are not available, the method cannot be recommended as "gold standard."
    Zeitschrift fur Orthopadie und Unfallchirurgie 04/2014; 152(2):120-9. · 0.65 Impact Factor
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    ABSTRACT: Periprosthetic joint infections (PJI) are often treated by two stage exchange with the use of an antibiotic impregnated spacer. Most of the two-stage exchange algorithms recommend the implantation of an antibiotic-impregnated spacer during the first stage for a period of 2-24 weeks before reimplantation of the new prosthesis. For the spacer to have a therapeutic effect, the local antibiotic concentration must be greater than the minimal inhibition concentration (MIC) against the pathogens causing the PJI. It must remain so for the entire spacer period, otherwise recurrence of infection or resistances might occur. The question as to whether a sufficient concentration of antibiotics in vivo is reached for the entire spacer period has not been answered satisfactorily. We here present a case of a histologically confirmed chronic PJI 20 month after primary arthroplasty. The primary knee arthroplasty was performed due to osteoarthritis of the joint. Initial assessment did not detect a causative pathogen, and two stage exchange with a vancomycin-gentamycin impregnated spacer was performed. At the time of reimplantation, sonication of the explanted spacer revealed a multi-resistant strain of staphylococcus epidermidis on the device and in the joint. Adaption of the therapy and prolonged treatment successfully eradicated the infection. According to the authors' knowledge, the case presented here confirms for the first time the surface contamination (proven through sonication) of a vancomycin-/gentamicin- impregnated Vancogenx(R)-spacer with a MRSE after ten weeks of implantation.This case study demonstrates the difficulties still associated with the diagnostics of PJI and the published different two stage treatment regimes with the use of antibiotic impregnated spacers.
    BMC Infectious Diseases 03/2014; 14(1):144. · 3.03 Impact Factor
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    ABSTRACT: Despite reliable results of ankle fusion for advanced haemophilic arthropathy, total ankle replacement (TAR) may be functionally advantageous. There is only very limited literature data available on TAR in patients with haemophilia. The objective of this study is to evaluate the short- and mid-term results after TAR in patients with end-stage haemophilic ankle arthropathy and concomitant virus infections. In a retrospective study, results after eleven TAR in 10 patients with severe (n = 8) and moderate (n = 2) haemophilia (mean age: 49 ± 7 years, range, 37-59) were evaluated at a mean follow-up of 3.0 years (range, 1.2-5.4). Nine patients were positive for hepatitis C, five were HIV-positive. Range of motion (ROM), AOFAS-hindfoot-score, pain status (visual analogue scale, VAS) as well as patient satisfaction were evaluated. In two cases deep prosthesis infection occurred leading to the removal of the implant. In the remaining eight patients the mean AOFAS score improved significantly from 21.5 to 68.0 points (P < 0.0005), the VAS score decreased significantly from 7.6 to 1.9 points (P < 0.0005). ROM increased from 23.2 to 25.0 degrees (P = 0.51). At final follow-up all patients without any complications were satisfied with the postoperative results. Radiographic examination did not reveal any signs of prosthetic loosening. TAR is a viable surgical treatment option in patients with end-stage ankle osteoarthritis due to haemophilia. It provides significant pain relieve and high patient satisfaction. However, due to the increased risk of infection and lack of long-term results, TAR particularly in patients with severe haemophilia and virus infections should be indicated carefully.
    Haemophilia 03/2014; · 3.17 Impact Factor
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    ABSTRACT: The preoperative differentiation between septic and aseptic loosening after total hip or knee arthroplasty is essential for successful therapy and relies in part on biomarkers. The objective of this study was to assess synovial and serum levels of inflammatory proteins as diagnostic tool for periprosthetic joint infection and compare their accuracy with standard tests. 120 patients presenting with a painful knee or hip endoprosthesis for surgical revision were included in this prospective trial. Blood samples and samples of intraoperatively acquired joint fluid aspirate were collected. White blood cell count, C-reactive protein, procalcitonin and interleukin-6 were determined. The joint aspirate was analyzed for total leukocyte count and IL-6. The definite diagnosis of PJI was determined on the basis of purulent synovial fluid, histopathology and microbiology. IL-6 in serum showed significantly higher values in the PJI group as compared to aseptic loosening and control, with specificity at 58.3% and a sensitivity of 79.5% at a cut-off value of 2.6 pg/ml. With a cut-off >6.6 pg/ml, the specificity increased to 88.3%. IL-6 in joint aspirate had, at a cut-off of >2100 pg/ml, a specificity of 85.7% and sensitivity of 59.4%. At levels >9000 pg/ml, specificity was almost at 100% with sensitivity just below 50%, so PJI could be considered proven with IL-6 levels above this threshold. Our data supports the published results on IL-6 as a biomarker in PJI. In our large prospective cohort of revision arthroplasty patients, the use of IL-6 in synovial fluid appears to be a more accurate marker than either the white blood cell count or the C-reactive protein level in serum for the detection of periprosthetic joint infection. On the basis of the results we recommend the use of the synovial fluid biomarker IL-6 for the diagnosis of periprosthetic joint infection following total hip and knee arthroplasty.
    PLoS ONE 01/2014; 9(2):e89045. · 3.53 Impact Factor
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    ABSTRACT: Crystal formation reflects the entire composition of the surrounding solution. In case of urolithiasis, induced crystal formation in native urine has led to the development of the Bonn-Risk-Index (BRI), a valuable tool to quantify an individual's risk of calcium oxalate urolithiasis. If the progression of a disease is associated with characteristic changes in the activities of urinary components, this leads to an altered urinary crystallisation capacity. Therefore, the results of induced urinary crystal formation can be used to detect and monitor any disease linked to the altered urinary composition. Since crystal formation inherently takes into account the entire urinary composition, the influence of the disease on individual urinary parameters does not have to be known in order to monitor the consequent pathologic alterations. In this paper, we review the background of urinary crystal formation analysis and describe its established application in urolithiasis monitoring as well as potential further fields of clinical application.
    EPMA Journal, The 01/2014; 5(1):13.
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    ABSTRACT: Joint associated tumors must undergo histological analysis, since not only inflammatory, but also benign and malign tumors exist in this location. We report a well circumscribed tumor, located in the elbow that histologically turned out to be a hibernoma. Complete surgical excision is the therapy of choice and recurrences are rare. To rule out liposarcoma with hibernoma like changes, fluorescence in-situ hybridisation has been performed and showed no MDM-2 amplification. Hibernomas are tumors of brown adipose tissue that may be localized next to joints.
    Zeitschrift fur Orthopadie und Unfallchirurgie 01/2014; 152:366-8. · 0.65 Impact Factor
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    ABSTRACT: Pantoea agglomerans is a rare isolate in orthopaedic patients. We describe the first case of an acute hip prosthetic joint infection (PJI) caused by Pantoea agglomerans. The microorganism was detected after sonication of the removed hip endoprosthesis.
    Technology and health care: official journal of the European Society for Engineering and Medicine 11/2013; · 0.64 Impact Factor
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    ABSTRACT: The aim of the therapy is mechanical and functional stabilization of high dislocated hips with dysplasia coxarthrosis using total hip arthroplasty (THA). Developmental dysplasia of the hip (DDH) in adults, symptomatic dysplasia coxarthrosis, high hip dislocation according to Crowe type III/IV, and symptomatic leg length inequality. Cerebrospinal dysfunction, muscular dystrophy, apparent disturbance of bone metabolism, acute or chronic infections, and immunocompromised patients. With the patient in a lateral decubitus position an incision is made between the anterior border of the gluteus maximus muscle and the posterior border of the gluteus medius muscle (Gibson interval). Identification of the sciatic nerve to protect the nerve from traction disorders by visual control. After performing trochanter flip osteotomy, preparation of the true actetabulum if possible. Implantation of the reinforcement ring, preparation of the femur and if necessary for mobilization, resection until the trochanter minor. Test repositioning under control of the sciatic nerve. Finally, refixation of the trochanteric crest. During hospital stay, intensive mobilization of the hip joint using a continuous passive motion machine with maximum flexion of 70°. No active abduction and passive adduction over the body midline. Maximum weight bearing 10-15 kg for 8 weeks, subsequently, first clinical and radiographic follow-up and deep venous thrombosis prophylaxis until full weight bearing. From 1995 to 2012, 28 THAs of a Crow type IV high hip-dislocation were performed in our institute. Until now 14 patients have been analyzed during a follow-up of 8 years in 2012. Mid-term results showed an improvement of the postoperative clinical score (Merle d'Aubigné score) in 86 % of patients. Good to excellent results were obtained in 79 % of cases. Long-term results are not yet available. In one case an iatrogenic neuropraxia of the sciatic nerve was observed and after trauma a redislocation of the arthroplasty appeared in another case. In 2 cases an infection of the THA appeared 8 and 15 months after index surgery. No pseudoarthrosis of the trochanter or aseptic loosening was noticed.
    Operative Orthopädie und Traumatologie 10/2013; 25(5):469-482. · 0.47 Impact Factor
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    ABSTRACT: A lateral, transgluteal approach for hip resurfacing carries the risk of approach-related weakening of the hip abductors due to unsuccessful re-adaptation of the gluteal muscles to the greater trochanter or to injury to the inferior nerve branch of the superior gluteal nerve.OBJECTIVE: We investigated whether hip resurfacing using a soft tissue-sparing, modified transgluteal approach with limited cranial splitting of the gluteus medius muscle reduces hip abductor strength and the risk of approach-related injury to the superior gluteal nerve.METHODS: Thirty-one patients (14 female, 17 male; mean age 53.5 ± 5.2 years) underwent hip resurfacing using a modified transgluteal approach with limited cranial splitting of the gluteus medius muscle. Nerve conduction signals were measured by surface electromyography (EMG), hip abductor strength by isokinetic testing a mean 36.2 months (±11 mos) after surgery. The unoperated side was used as control. Surface EMG disclosed no neural lesions of the inferior branch of the superior gluteal nerve. Isokinetics revealed a significant reduction in muscle strength on the operated versus the contralateral side. Even a limited incision of the gluteus medius muscle resulted in significant impairment of hip abductor strength 2.5 years after surgery.
    Technology and health care: official journal of the European Society for Engineering and Medicine 09/2013; · 0.64 Impact Factor

Publication Stats

213 Citations
146.82 Total Impact Points

Institutions

  • 2007–2014
    • University of Bonn
      • Klinik und Poliklinik für Orthopädie und Unfallchirurgie
      Bonn, North Rhine-Westphalia, Germany
    • Orthopädische Klinik Markgröningen
      Ludwigsburg, Baden-Württemberg, Germany
  • 2008–2013
    • University of Bonn - Medical Center
      Bonn, North Rhine-Westphalia, Germany
  • 2007–2012
    • RWTH Aachen University
      • • Helmholtz Institute of Biomedical Engineering
      • • Department of Orthopaedics and Trauma Surgery
      Aachen, North Rhine-Westphalia, Germany
  • 2007–2009
    • University Hospital RWTH Aachen
      • Department of Orthodontics
      Aachen, North Rhine-Westphalia, Germany