Minimum 10-Year Clinical Outcome of Lateral Collagen Meniscal Implants for the Replacement of Partial Lateral Meniscal Defects: Further Results From a Prospective Multicenter Study

Background: The collagen meniscal implant (CMI) is a biologic scaffold aimed at replacing partial meniscal defects. The long-term results of lateral meniscal replacement have never been investigated. Purpose: To document the clinical outcomes and failures of lateral CMI implantation for partial lateral meniscal defect at a minimum 10-year follow-up. Study Design: Case series; Level of evidence, 4, Methods: This study included 24 consecutive patients who underwent lateral CMI implantation for partial lateral meniscal defects between April 2006 and September 2009 and who were part of a previous study with a 2-year follow-up. Outcome measures at the latest follow-up included the Lysholm score, Knee injury and Osteoarthritis Outcome Score, visual analog scale (VAS) for pain, Tegner activity level, and EuroQol 5-Dimensions score. Data regarding complications and failures were collected, and patients were asked about their satisfaction with the procedure. Results: Included in the final analysis were 19 patients (16 male, 3 female) with a mean age at surgery of 37.1 ± 12.6 years and a mean follow-up of 12.4 ± 1.5 years (range, 10-14 years). Five failures (26%) were reported: 1 CMI removal because of implant breakage and 4 joint replacements (2 unicompartmental knee arthroplasties and 2 total knee arthroplasties). The implant survival rate was 96% at 2 years, 85% at 5 years, 85% at 10 years, 77% at 12 years, and 64% at 14 years. Lysholm scores at the final follow-up were rated as “excellent” in 36% (5 of 14 nonfailures), “good” in 43% (6 of 14), and “fair” in 21% (3 of 14). The VAS score was 3.1 ± 3.1, with only 16% (3 of 19 patients) reporting that they were pain-free; the median Tegner score was 3 (interquartile range, 2-5). All clinical scores decreased from the 2-year follow-up; however, with the exception of the Tegner score, they remained significantly higher compared with the preoperative status. Overall, 79% of patients were willing to undergo the same procedure. Conclusion: Lateral CMI implantation for partial lateral meniscal defects provided good long-term results, with a 10-year survival rate of 85% and a 14-year survival rate of 64%. At the final follow-up, 58% of the patients had “good” or “excellent” Lysholm scores. However, there was a general decrease in outcome scores between the short- and the long-term follow-up

Autologous chondrocyte implantation using a bilayer collagen membrane: A preliminary report

Purpose. To present preliminary clinical experience with Matrix-induced autologous chondrocyte implantation, a new tissue-engineering technique for treatment of deep cartilage defects, in which autologous chondrocytes are seeded on a tridimensional scaffold provided by a bilayer type I–III collagen membrane. Methods. From December 1999 to January 2001, 13 patients underwent implantation procedure for deep cartilage defects. Age of patients ranged from 18 to 49 years (mean age, 35 years). The mean defect size was 3.5 cm 2 (range, 2.0–4.5 cm 2 ). Clinical and functional evaluation were performed using various score systems for the ankle and the knee, and magnetic resonance imaging was performed at 6 and 12 months postoperatively. Membrane structure and cellular population were investigated by light microscopy, scanning electron microscopy, and electrophoresis before implantation. Results. The mean follow-up was 6.5 months (range, 2–15 months). No complications were observed in the postoperative period. The 6 patients with a minimum follow-up of 6 months showed an improvement in clinical and functional status after surgery. Magnetic resonance images showed the presence of hyaline-like cartilage at the site of implantation; there was evidence of chondroblasts and type II collagen inside the seeded membrane. Conclusion. Matrix-induced autologous chondrocyte implantation offers several advantages with respect to the traditional cultured cell procedure. These include technical simplicity, short operating time, minimal invasiveness, and easier access to difficult sites. It appears to be a reliable method for the repair of deep cartilage defects

Performance of the EUDET-type beam telescopes

Test beam measurements at the test beam facilities of DESY have been conducted to characterise the performance of the EUDET-type beam telescopes originally developed within the EUDET project. The beam telescopes are equipped with six sensor planes using MIMOSA26 monolithic active pixel devices. A programmable Trigger Logic Unit provides trigger logic and time stamp information on particle passage. Both data acquisition framework and offline reconstruction software packages are available. User devices are easily integrable into the data acquisition framework via predefined interfaces. The biased residual distribution is studied as a function of the beam energy, plane spacing and sensor threshold. Its standard deviation at the two centre pixel planes using all six planes for tracking in a 6\,GeV electron/positron-beam is measured to be (2.88\,\pm\,0.08)\,\upmu\meter.Iterative track fits using the formalism of General Broken Lines are performed to estimate the intrinsic resolution of the individual pixel planes. The mean intrinsic resolution over the six sensors used is found to be (3.24\,\pm\,0.09)\,\upmu\meter.With a 5\,GeV electron/positron beam, the track resolution halfway between the two inner pixel planes using an equidistant plane spacing of 20\,mm is estimated to (1.83\,\pm\,0.03)\,\upmu\meter assuming the measured intrinsic resolution. Towards lower beam energies the track resolution deteriorates due to increasing multiple scattering. Threshold studies show an optimal working point of the MIMOSA26 sensors at a sensor threshold of between five and six times their RMS noise. Measurements at different plane spacings are used to calibrate the amount of multiple scattering in the material traversed and allow for corrections to the predicted angular scattering for electron beams

In vitro inhibition of HIV-1 by Met-SDF-1β alone or in combination with antiretroviral drugs

Compounds that can block the CXCR4 chemokine receptor are a promising new class of antiretroviral agents. In these experiments we studied the effect of a modified form of the native stromal cell-derived factor- 1 (SDF-1), Met-SDF-1\u3b2. The in vitro susceptibility of two different CXCR4-tropic HIV-1 strains was determined. Antiviral effect was assessed by the reduction of p24 antigen production in PHA-stimulated peripheral blood mononuclear cells with exposure to the modified SDF-1 molecule. The 50% inhibitory concentrations (IC50) were derived from six separate experiments. The IC50 against the two HIV-1 isolates was in 1.0-2.8 \u3bcg/ml range for Met-SDF-1\u3b2. Met-SDF-1\u3b2 showed synergy to additivity with either zidovudine or nelfinavir at IC75, IC90 and IC95. Additivity was seen when Met-SDF-1\u3b2 was combined with efavirenz. No cellular toxicity was observed at the highest concentrations when these agents were used either singly or in combination. This compound is a promising new candidate in a receptor-based approach to HIV-1 infection in conjunction with currently available combination antiretroviral drug therapies

Infrastructure for Detector Research and Development towards the International Linear Collider

The EUDET-project was launched to create an infrastructure for developing and testing new and advanced detector technologies to be used at a future linear collider. The aim was to make possible experimentation and analysis of data for institutes, which otherwise could not be realized due to lack of resources. The infrastructure comprised an analysis and software network, and instrumentation infrastructures for tracking detectors as well as for calorimetry.Comment: 54 pages, 48 picture

Two stage fracture of a polyethylene post in a 9-year-old posterior-stabilized knee prosthesis: a case report

<p>Abstract</p> <p>Introduction</p> <p>Several cases of tibial post breakage are reported in the literature. To the best of our knowledge, only three cases of NexGen knee prosthesis (Zimmer, Warsaw, Indiana, USA) tibial post failure have been reported.</p> <p>Case presentation</p> <p>In November 1999, a 63-year-old Caucasian woman from Italy with a history of symptomatic left knee osteoarthritis underwent a total knee arthroplasty. In March 2008, while rising from a chair, she felt a sudden pain and instability in her left knee. She reported a fracture of the polyethylene post of the tibial insert. No malposition or malalignment of either the femoral or tibial components were identified. The polyethylene tibial insert was studied under light microscopy and scanning electron microscopy. The fracture was also noted to have occurred without any notable polyethylene wear.</p> <p>Conclusion</p> <p>Scanning electron microscopy revealed two different damage patterns that could be explained with a two-stage rupture of our patient's polyethylene post. This could have been caused by a non-optimal ligamentous balancing during first implant surgery. Her knee probably developed a varus instability that weakened the post, and then a posterior anterior stress finally broke the polyethylene.</p

Risk of obstructive sleep apnea with daytime sleepiness is associated with liver damage in non-morbidly obese patients with nonalcoholic Fatty liver disease

BACKGROUND: A high prevalence of obstructive sleep apnea syndrome (OSAS) has been reported in severely obese patients with nonalcoholic fatty liver disease (NAFLD), but few studies have evaluated OSAS in non-morbidly obese NAFLD patients. AIMS: To determine the prevalence of risk for OSAS with or without daytime sleepiness in non-morbidly obese patients with NAFLD and evaluate the association with the severity of liver damage. METHODS: We considered 159 consecutive patients with histological NAFLD and body mass index (BMI) <35 Kg/m2, and 80 controls without ultrasonographic steatosis matched for age, sex, and BMI. OSAS risk was determined by positivity for Berlin questionnaire (BQ), and daytime sleepiness by the Sleepness Epworth Scale (ESS). Liver damage was evaluated according to the NAFLD activity score. RESULTS: In NAFLD patients, BQ alone was positive in 39 (25%), ESS in 8 (5%), and both in 13 (8%, OSAS with sleepines); p\u200a=\u200ans vs. controls without steatosis. In NAFLD patients at risk for OSAS with (but not in those without) sleepiness, we observed a higher prevalence of nonalcoholic steatohepatitis (NASH; 11/13, 85% vs. 72/146, 49%; p\u200a=\u200a0.018), and of clinically significant fibrosis (stage>1; 9/13, 69% vs. 39/146, 27%; p\u200a=\u200a0.003). At multivariate logistic regression analysis, OSAS with sleepiness was strongly associated with NASH and fibrosis>1 independently of known clinical risk factors such as age, gender, BMI, diabetes, and ALT levels (OR 7.1, 95% c.i. 1.7-51, p\u200a=\u200a0.005 and OR 14.0, 95% c.i. 3.5-70, p\u200a=\u200a0.0002, respectively). CONCLUSIONS: A proportion of NAFLD patients without severe obesity is at risk for OSAS with daytime sleepiness, which is associated with the severity of liver damage independently of body mass and other cofactors