[Silver coating on tumour prostheses]. / Silberbeschichtung auf Tumorendoprothesen.

BACKGROUND: Modular endoprostheses, so-called "tumour or megaprostheses" are mainly used for limb salvage surgery after resection of malignant soft tissue or a bone tumour. Sometimes, this type of prosthesis is also used for revision surgeries after failed primary joint arthroplasty. Despite continuously improving techniques and quality management systems, periprosthetic infection is one of the most serious complications. AIM OF THE STUDY: Review of the literature in the PubMed data base with the main focus on silver coatings in joint arthroplasty and their effect on infection rate, outcome and patients' safety. RESULTS: The current literature shows that there is a beneficial role of silver coatings in megaprostheses in terms of revision rates for septic complications, especially following tumour resection with bad soft tissue coverage or in (multimorbid) high-risk patients, compared to uncoated implants. DISCUSSION: Based on the results of previous publications examining blood or serum silver concentrations or silver levels in urine, silver coatings do not appear to have side effects, except for local argyria. Continuous monitoring of silver levels in blood or serum is still recommended, and additional long-term studies will be necessary to verify the effectiveness and safety of silver coatings.

Clinical Results and Serum Metal Ion Concentrations following Ceramic-on-Metal Total Hip Arthroplasty at a Mean Follow-Up of 60 Months.

Background. Increased metal ion levels following total hip arthroplasty (THA) with metal-on-metal bearings are a highly debated topic. Local soft tissue reactions with chronic pain and systemic side effects such as neuropathy are described. The aim of the current study was to determine the serum metal ion concentrations of Cobalt (Co) and Chrome (Cr) after THA with a ceramic-on-metal (CoM) bearing. Patients and Methods. Between 2008 and 2010, 20 patients underwent THA using a CoM bearing. Clinical function was evaluated by standardized scores systems (Harris Hip Score and WOMAC Score) and radiological examination included X-rays. Patient's blood samples were obtained for metal ion analysis and correlation analysis was done between these results and implant position. Results. Overall, 13 patients with 14 CoM devices were available for the current series. The mean age at time of surgery was 61 years (range, 41 to 85). The postoperative follow-up ranged from 49 to 68 months (mean, 58). Metal ion determination showed mean concentrations of 3,1 µg/L (range, 0,3-15,2 µg/L) for Co and 1,6 µg/L (range, 0,1-5,5 µg/L) for Cr, respectively. A correlation between cup anteversion and Co and Cr concentrations was shown. Conclusion. The current series showed increments for Co and Cr following CoM THA. However, these levels are lower compared to metal ion concentrations in patients with metal-on-metal bearings and the international accepted threshold for revision of MoM devices. We recommend routine follow-up including at least one obligatory evaluation of serum metal ion concentrations and an MRI once to exclude local soft tissue reactions.

Serum sclerostin levels in renal cell carcinoma patients with bone metastases.

Sclerostin has been proposed as a potent inhibitor of bone formation. Sclerostin antibodies are under clinical development to treat osteoporosis and metastatic bone disease. Serum sclerostin level is elevated in multiple myeloma, an osteolytic malignancy, where it might serve as predictive marker for the use of sclerostin-directed antibodies. As renal cell carcinoma (RCC) patients often present with osteolytic metastases, we aimed to investigate serum sclerostin levels in RCC patients. Our study included 53 RCC patients (19 with bone metastases, 25 with visceral metastases and 9 with localized disease) and 53 age- and gender-matched non-osteoporotic controls. Frozen serum samples were subjected to sclerostin quantitative sandwich ELISA. The mean serum sclerostin levels of RCC patients and controls were 45.8 pmol/l and 45.1 pmol/l, respectively (p = 0.86). Analysis of variance showed no difference between the subgroups of RCC patients with regard to visceral or bone metastases or localized disease (p = 0.22). There was no significant association between eGFR (estimated glomerular filtration rate) and serum sclerostin levels in RCC patients (r = 0.05; p = 0.74) and controls (r = 0.06; p = 0.68). Our results indicate that serum sclerostin levels appear not to be a valuable biomarker to assess the occurrence of bone metastases in RCC patients.

The width of resection margins influences local recurrence in soft tissue sarcoma patients.

BACKGROUND: Patients with soft tissue sarcoma (STS) being treated following the standardized guidelines can still not be guaranteed to remain free from local recurrence (LR). A complete tumour resection has been accepted as a major prognostic factor for LR. This retrospective study was designed to analyse the influence of two different classifications of resection margins (R-classification and UICC-classification) on LR in STS patients. MATERIALS AND METHODS: Of 411 patients treated at our institution for STS, 265 were eligible for statistical analysis. Kaplan-Meier curves and Cox regression models were used to assess the impact of an R0 resection according to the R-classification (resection margin clear but allowing <1 mm) and according to the UICC-classification (minimal resection margin ≥1 mm) on LR. RESULTS: Survival curves showed a lower LR rate for R0 resections in the UICC-classification, namely 1.3%, 12% and 12% as compared to 2.1%, 9.5% and 16.5% for the R-classification. In multivariate analysis calculated separately for each classification, R1 resection as defined by the R-classification (HR: 11.214; 95%CI: 2.394-52.517; p = 0.002) as well as by UICC-classification (HR: 15.634; 95%CI: 2.493-98.029; p = 0.003) remained significant. CONCLUSION: In our study, margin status according to both classifications represents an independent prognostic factor for LR in patients with STS following curative surgery. Local control rates were superior after a minimal resection margin of 1 mm (R0 by UICC-classification) compared to R0 resections after the R-classification.

Validation of the prognostic relevance of plasma C-reactive protein levels in soft-tissue sarcoma patients.

BACKGROUND: The concept of the involvement of systemic inflammation in cancer progression and metastases has gained attraction within the past decade. C-reactive protein (CRP), a non-specific blood-based marker of the systemic inflammatory response, has been associated with decreased survival in several cancer types. The aim of the present study was to validate the prognostic value of pre-operative plasma CRP levels on clinical outcome in a large cohort of soft-tissue sarcoma (STS) patients. METHODS: Three hundred and four STS patients, operated between 1998 and 2010, were retrospectively evaluated. CRP levels and the impact on cancer-specific survival (CSS), disease-free survival (DFS) and overall survival (OS) were assessed using Kaplan-Meier curves and univariate as well as multivariate Cox proportional models. Additionally, we developed a nomogram by supplementing the plasma CRP level to the well-established Kattan nomogram and evaluated the improvement of predictive accuracy of this novel nomogram by applying calibration and Harrell's concordance index (c-index). RESULTS: An elevated plasma CRP level was significantly associated with established prognostic factors, including age, tumour grade, size and depth (P<0.05). In multivariate analysis, increased CRP levels were significantly associated with a poor outcome for CSS (HR=2.05; 95% CI=1.13-3.74; P=0.019) and DFS (HR=1.88; 95% CI=1.07-3.34; P=0.029). The estimated c-index was 0.74 using the original Kattan nomogram and 0.77 when the plasma CRP level was added. CONCLUSION: An elevated pre-operative CRP level represents an independent prognostic factor that predicts poor prognosis and improves the predictive ability of the Kattan nomogram in STS patients. Our data suggest to further prospectively validate its potential utility for individual risk stratification and clinical management of STS patients.

Argyria following the use of silver-coated megaprostheses: no association between the development of local argyria and elevated silver levels.

The aims of this study were to evaluate the incidence of local argyria in patients with silver-coated megaprostheses and to identify a possible association between argyria and elevated levels of silver both locally and in the blood. Between 2004 and 2011, 32 megaprostheses with silver coatings were implanted in 20 female and 12 male patients following revision arthroplasty for infection or resection of a malignant tumour, and the levels of silver locally in drains and seromas and in the blood were determined. The mean age of the patients was 46 years (10 to 81); one patient died in the immediate post-operative period and was excluded. Seven patients (23%) developed local argyria after a median of 25.7 months (interquartile range 2 to 44.5). Patients with and without local argyria had comparable levels of silver in the blood and aspiration fluids. The length of the implant did not influence the development of local argyria. Patients with clinical evidence of local argyria had no neurological symptoms and no evidence of renal or hepatic failure. Thus, we conclude that the short-term surveillance of blood silver levels in these patients is not required.

[Bone metastases treatment strategies]. / Behandlungsstrategien bei Skelettmetastasen.

The primary goals of multimodal, interdisciplinary treatment of bone metastases are to achieve mobility, pain relief, and improve quality of life. In cooperation with radiotherapists and oncologists, an individual therapy plan has to be designed. As bone metastases are a sign of a systemic spread of the disease, cure is not possible in nearly all cases. A singular bone metastasis of a renal cell carcinoma may be regarded as an exemption, where wide resection might cure the patient. The extent of the operation should be based on the 3S principle "save, short & simple". The prognosis of survival should influence the treatment regime. If it is unclear whether a bone metastasis or a primary bone tumor is present, a biopsy is required.

Metal ion levels in large-diameter total hip and resurfacing hip arthroplasty--preliminary results of a prospective five year study after two years of follow-up.

BACKGROUND: Metal-on-metal hip resurfacing is an alternative to metal-on-metal total hip arthroplasty, especially for young and physically active patients. However, wear which might be detected by increased serum ion levels is a matter of concern. METHODS: The aims of this preliminary study were to determine the raise of metal ion levels at 2-years follow-up in a prospective setting and to evaluate differences between patients with either resurfacing or total hip arthroplasty. Furthermore we investigated if the inclination of the acetabular component and the arc of cover would influence these findings. Therefore, 36 patients were followed prospectively. RESULTS: The results showed increments for Co and Cr in both implant groups. Patients treated with large-diameter total hip arthroplasty showed fourfold and threefold, respectively, higher levels for Co and Cr compared to the resurfacing group (Co: p < 0,001 and Cr: p = 0,005). Nevertheless, we observed no significant correlation between serum ion levels, inclination and arc of cover. DISCUSSION: In order to clarify the biologic effects of ion dissemination and to identify risks concerning long-term toxicity of metals, the exposure should be monitored carefully. Therefore, long-term studies have to be done to determine adverse effects of Co and Cr following metal-on-metal hip replacement.

[Clinical and radiological outcome after trapezium resection with suspension and interposition arthroplasty]. / Klinische und radiologische Ergebnisse der Resektions-Suspensions-Interpositionsarthroplastik bei Rhizarthrose.

INTRODUCTION: Trapezium resection with suspension and interposition arthroplasty of the thumb-carpometacarpal joint is a common method for treatment of severe osteoarthritis of the 1st carpometacarpal joint. METHODS: We performed a single center retrospective data analysis after trapezium resection with suspension and interposition arthroplasty of the thumb-carpometacarpal joint with emphasis on quality of life and radiological parameters 3.4 years (1.2-8.7 years) after operation in 60 patients. Pre- and postoperative pain was analysed with VAS, function was measured using the DASH score, pinch grip power with a pinchmeter. RESULTS: Subjective outcome was rated excellent in 42 cases (64.6%), good in 17 (26.2%), fair in 3 (4.6%) and 3 times (4.6%) poor. 56 patients (93.3%) would like to be operated again; 4 patients (6.7%) would deny an operation retrospectively. In the VAS pain was reduced by about 75% compared to the preoperative value. The pinch grip was increased by 46.6% compared to the preoperative value. The rate of major complications was 1.5% and of minor complications 9.2 %. CONCLUSION: Trapezium resection with suspension and interposition arthroplasty can increase the quality of life and reduce pain in patients with severe osteoarthritis of the 1st carpometacarpal joint. The rate of complications is low. Outcome assessment is possible by subjective parameters. Objective values like the range of movement or the decrease of the distance between metacarpal I and scaphoid do not correlate with outcome.

[A case of a tumorsimulating expansion caused by anabolic androgen steroids in body building]. / Steroid-Doping im Bodybuilding - Ursache für eine tumorsimulierende Expansion.

Despite intensive information on possible side effects and complications of performance-enhancing substances in sports, the use of AAS (anabolic androgen steroids) is far common. Particularly in sports like bodybuilding or weight lifting AAS are used for setting up muscle mass and increasing muscle power. We present the case of a 27 year old bodybuilder, who was transferred due to suspected malignant expansion of the upper limb to a department of orthopaedic surgery, not knowing that the patient had injected AAS. At biopsy the tumor was found to be an abscess formation, that had to be treated surgically with curettage. The microbiological analysis detected an infection with Pseudomonas fluorescens and Erwinia species. Erwinia species are associated with plants, Pseudomonas fluorescens is found in feces, sewage and soil. It is obvious, that the infection is caused by an inappropriate injection of AAS or by the contamination of the injected substances.