Jörg Friesenbichler

Effect of Platelet-Rich Plasma on the Biologic Activity of the Human Rotator-Cuff Fibroblasts: A Controlled In Vitro Study

To assess the in vitro effect of platelet‐rich plasma (PRP) on biological activity of the human rotator cuff fibroblasts and to describe the optimal dose‐response to maximize cellular stimulation while reducing potential risk. Rotator cuff (RC) fibroblasts of n = 6 patients (mean age of 65.2 years) undergoing arthroscopic cuff tear reconstruction were cultured in vitro for 21 days and stimulated with PRP in three different concentrations (1‐, 5‐, and 10‐fold). Samples were obtained for DNA and GAG measurement at 1, 7, 14, and 21 days. The biological outcomes were regressed on the PRP concentration. The application of PRP significantly influenced the fibroblast proliferation and activity of the human rotator cuff with elevated glycosaminoglycan (GAG) and DNA levels. The dosage of PRP had the significantly highest impact on this proliferation using a onefold or fivefold application. PRP has a significant effect on fibroblast proliferation of the human rotator cuff in vitro with an optimal benefit using a onefold or fivefold PRP concentration. This study justifies further in vivo investigations using PRP at the human rotator cuff.

Argyria following the use of silver-coated megaprostheses

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.

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

BackgroundMetal-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.MethodsThe 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.ResultsThe 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.DiscussionIn 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.

Serum Metal Ion Concentrations in Paediatric Patients following Total Knee Arthroplasty Using Megaprostheses

The purpose of this study was to determine the concentrations of cobalt, chromium, and molybdenum in the serum of paediatric tumour patients after fixed hinge total knee arthroplasty. Further, these metal ion levels were compared with serum metal ion levels of patients with other orthopaedic devices such as hip and knee prostheses with metal-on-metal or metal-on-polyethylene articulation to find differences between anatomical locations, abrasion characteristics, and bearing surfaces. After an average follow-up of 108 months (range: 67 to 163) of 11 paediatric patients with fixed hinge total knee arthroplasty, the mean concentrations for Co and Cr were significantly increased while Mo was within the limits compared to the upper values from the reference laboratory. Furthermore, these serum concentrations were significantly higher compared to patients with a standard rotating hinge device (P = 0.002 and P < 0.001) and preoperative controls (P < 0.001). On the other hand, the serum levels of patients following MoM THA or rotating hinge arthroplasty using megaprostheses were higher. Therefore, periodic long-term follow-ups are recommended due to the rising concerns about systemic metal ion exposure in the literature. Upon the occurrence of adverse reactions to metal debris the revision of the fixed hinge implant should be considered.

Evaluating the tibial and femoral insertion site of the anterior cruciate ligament using an objective coordinate system: A cadaver study

PURPOSE The purpose of this study was to evaluate the tibial and femoral insertion site of the anterior cruciate ligament (ACL) using an objective coordinate system in a cadaver study in order to confirm radiological assumptions of previous investigators who identified the tibial footprint (T) of the ACL on T (5.3; 5.5) and the femoral footprint (F) on F (2.9; 3.5). METHODS The tibial and femoral insertion site of the ACL was analysed on 30 human cadaver knee joints preserved according to the technique by Thiel. Thirty femora and tibiae were photographed under standardised methods and measured on a coordinate system twice by two examiners with respect to the ACLs footprint. We evaluated these measurements by use of the Cohens kappa inter- and intraobserver coefficient for two observers. RESULTS The photographs and tibial and femoral measurements were achieved with an almost perfect and a substantial agreement of inter- and intraobserver coefficients. Further, we could demonstrate that assumptions of anatomic points in previous radiological investigations were correct. CONCLUSIONS Our findings confirmed the anatomic tibial and femoral ACL footprint of a previous investigation and further the reproducibility of our coordinate system as an objective method for graft placement evaluation.

Impact of preoperative antithrombotic therapy on blood management after implantation of primary total knee arthroplasty

Red blood cell concentrates (RCC) substitution after total knee arthroplasty (TKA) is correlated with multifold of complications and an independent predictor for higher postoperative mortality. TKA is mainly performed in elderly patients with pre-existing polymorbidity, often requiring permanent preoperative antithrombotic therapy (PAT). The aim of this retrospective analysis was to investigate the impact of demand for PAT on inpatient blood management in patients undergoing TKA. In this study 200 patients were retrospectively evaluated after TKA for differences between PAT and non-PAT regarding demographic parameters, preoperative ASA score > 2, duration of operation, pre-, and intraoperative hemoglobin level, and postoperative parameters including amount of wound drainage, RCC requirement, and inpatient time. In a multivariate logistic regression analysis the independent influences of PAT, demographic parameters, ASA score > 2, and duration of the operation on RCC demand following TKA were analyzed. Patients with PAT were significantly older, more often had an ASA > 2 at surgery, needed a higher number of RCCs units and more frequently and had lower perioperative hemoglobin levels. Multivariate logistic regression revealed PAT was an independent predictor for RCC requirement. PAT patients are more likely to require RCC following TKA and should be accurately monitored with respect to postoperative blood loss.

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. Patients 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.

Three Metachronous Osteosarcomas within 22 Years without Pulmonary Metastases: A Case Report and Review of the Literature

Introduction. We present the extremely rare case of a patient with three metachronous osteosarcomas within 22 years without evident pulmonary manifestation of disease 30 years after first diagnosis. Case Presentation. In 1983, a high-grade osteosarcoma of the left distal femur was diagnosed in an 18-year-old Caucasian male. He received rotationplasty accompanied by pre- and postoperative chemotherapy. Ten years later, an osteoblastic osteosarcoma occurred in TH12. En bloc resection and pre- and postoperative chemotherapy followed. In 2005, the patient developed another high-grade osteosarcoma in his right distal femur. Treatment included a wide resection and reconstruction with a tumour endoprosthesis as well as (neo)adjuvant chemotherapy. After the third tumour occurrence, cytogenetic and molecular genetic examinations (p53, rb1) were performed, showing a normal genetic pattern. Screening for metastases never showed clinical evidence of extraskeletal tumour manifestation. Discussion. In patients presenting metachronous osteosarcoma, identification of their lesions clonality (second primary tumour or metastases) could lead to a better understanding of tumour development and help to filter patients who need extended long-term followup due to a higher risk of late occurring sarcoma recurrence.

Pathologic fracture of the distal humerus due to a textiloma

Textiloma, also known as gossypiboma, is defined as a tumor-simulating process composed of cotton matrix or synthetic fibers surrounded by granulomatous reactions resulting from retained surgical gauzes. Forgotten surgical material, despite precautions taken, is well described in the literature. The global occurrence is estimated to be between 1 in 1000 and 1 in 10,000 interventions. Most of the cases result from abdominal surgery (52%) and gynecologic surgery (22%). The most common localization of textilomas is in the abdomen, with 75%, whereas only 6% occur in the extremities. Reports of textilomas after musculoskeletal surgical procedures in the upper extremity are rare. The cotton matrix or synthetic fibers of a retained surgical gauze are not absorbable. The human body reacts to a retained surgical gauze in 2 ways, either (1) exudative, with abscess formation, or (2) with an aseptic fibrous inflammatory response, producing adhesions and encapsulation. The clinical presentation can be either acute or delayed. Because of secondary superinfections and sepsis or formation of fistulas, the exudative form manifests earlier clinically. The delayed form appears after 2 or more years and is usually a tumorous mass. In a few cases, patients stay asymptomatic for many years and the textiloma is discovered incidentally. Because of the polymorphism and the presumptive malignant degeneration, the diagnosis can be very challenging and investigations such as computed tomography (CT) and magnetic resonance imaging (MRI), which do not always give reliable diagnoses, are often performed. A textiloma could be misinterpreted as a chondrosarcoma, osteosarcoma, chronic expanding hematoma, or metastasis. Definitive diagnosis can only be made by histopathologic examination. Pathologic fracture due to a textiloma has been reported in only 2 patients so far, with the textiloma occurring in the thigh in both cases. We report a case of a pathologic fracture of the distal humerus due to a textiloma.

[Osteosarcoma: reliability and quality of the information in the internet].

ZusammenfassungDas World Wide Web ist als medizinische Informationsquelle für Fachpersonal wie gleichsam für Laien und Patienten in den letzten Jahren zu einem bedeutenden und häufig verwendeten Nachschlagewerk herangewachsen. Die Qualität dieser Informationen ist jedoch vom anarchischen Aufbau des Internets sowie von Führung und Aufbau der Internetseiten abhängig. Die vorliegende Querschnittstudie bewertet und vergleicht die Vertrauenswürdigkeit und Informationsqualität hinsichtlich des Osteosarkoms auf den gängigsten deutschsprachigen Internetseiten für medizinische Information. Das Osteosarkom ist, als einer der häufigsten bösartigen primären Knochentumore sowie durch das Inzidenzmaximum im Kindes- und Jugendalter, in der orthopädischen Onkologie von besonderer Bedeutung.SummaryThe World Wide Web has grown during the last years to a considerable source of medical information for experts as well as for laymen and patients. The quality of this information is subjected to some limitation linked with the structure of the Internet and the management of Internet pages. The cross- sectional study presented evaluates and compares quality and reliability of information with respect of osteosarcoma in the most common German-language Internet pages for medical information. As both, one of the most common primary malignant bone tumors and its peak of incidence at the age of childhood and youth, osteosarcoma is considered of significant importance in orthopedic oncology.