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Introduction: Meniscal allograft transplantation seems to be a valid therapeutic option to restore the knee function and limit the development of osteoarthritis after menisectomy. No surgical technique has been shown to provide better results than others. The main objective of this study was to assess graft healing after arthroscopic meniscal allograft transplantation without bone plugs. Methods: This retrospective study included all patients who underwent arthroscopic meniscal allograft transplantation during 2005-2010. The meniscal horns were fixed through two tibia tunnels without bone plugs. The primary endpoint was graft healing according to Henning's criteria on MR arthrography (MRA) at 6-month follow-up. The secondary endpoints were the KOOS questionnaire, the IKDC score, measurement of the joint space and meniscal extrusion on both MRA at 6-month and MRI at last follow-up. The series included 22 patients, mean age 37 ± 7.5 years. The allograft was lateral in 20 cases and medial in 2 cases. The mean follow-up was 4.4 ± 1.6 years with one lost to follow-up. Results: MR arthrography was performed in 14/21 patients at 6-months of follow-up: 8/14 (57.1 %) had total graft healing, 2/14 (14.3 %) partial healing and 4/14 (28.6 %) no healing. At final follow-up, all functional scores had significantly improved. The average pre- and post-operative joint space thickness was similar. MRI showed meniscal extrusion in 75 % of patients. Conclusion: The meniscal allograft transplantation without bone plugs effectively treats painful and functional sequellae of meniscectomies. The graft healed in most patients at 6-month follow-up. The long-term clinical relevance of meniscal extrusion has to be evaluated. Level of evidence: Retrospective study, Level IV. [ABSTRACT FROM AUTHOR]

This paper provides an overview of the PACS photometer flux calibration concept, in particular for the principal observation mode, the scan map. The absolute flux calibration is tied to the photospheric models of five fiducial stellar standards ( α Boo, α Cet, α Tau, β And, γ Dra). The data processing steps to arrive at a consistent and homogeneous calibration are outlined. In the current state the relative photometric accuracy is ∼2 % in all bands. Starting from the present calibration status, the characterization and correction for instrumental effects affecting the relative calibration accuracy is described and an outlook for the final achievable calibration numbers is given. After including all the correction for the instrumental effects, the relative photometric calibration accuracy (repeatability) will be as good as 0.5 % in the blue and green band and 2 % in the red band. This excellent calibration starts to reveal possible inconsistencies between the models of the K-type and the M-type stellar calibrators. The absolute calibration accuracy is therefore mainly limited by the 5 % uncertainty of the celestial standard models in all three bands. The PACS bolometer response was extremely stable over the entire Herschel mission and a single, time-independent response calibration file is sufficient for the processing and calibration of the science observations. The dedicated measurements of the internal calibration sources were needed only to characterize secondary effects. No aging effects of the bolometer or the filters have been found. Also, we found no signs of filter leaks. The PACS photometric system is very well characterized with a constant energy spectrum νF = λF = const as a reference. Colour corrections for a wide range of sources SEDs are determined and tabulated. [ABSTRACT FROM AUTHOR]

We present a flux calibration scheme for the PACS chopped point-source photometry observing mode based on the photometry of five stellar standard sources. This mode was used for science observations only early in the mission. Later, it was only used for pointing and flux calibration measurements. Its calibration turns this type of observation into fully validated data products in the Herschel Science Archive. Systematic differences in calibration with regard to the principal photometer observation mode, the scan map, are derived and amount to 5 − 6 %. An empirical method to calibrate out an apparent response drift during the first 300 Operational Days is presented. The relative photometric calibration accuracy (repeatability) is as good as 1 % in the blue and green band and up to 5 % in the red band. Like for the scan map mode, inconsistencies among the stellar calibration models become visible and amount to 2 % for the five standard stars used. The absolute calibration accuracy is therefore mainly limited by the model uncertainty, which is 5 % for all three bands. [ABSTRACT FROM AUTHOR]

Tillaux fractures are relatively uncommon fractures of the anterolateral tibial epiphysis that are observed in adolescents during the 18-month period when the distal tibial physis has begun to fuse centrally. The case of a 16-year-old boy with a juvenile Tillaux fracture treated successfully by reduction and percutaneous fixation under arthroscopic control is presented. The procedure is technically feasible, allows accurate reconstruction of the weight bearing surface of the joint and secure internal fixation of the fracture. The authors describe the principles of the procedure and discuss its advantages compared to open surgery. [ABSTRACT FROM AUTHOR]