1.The Efficacy of Medial Patellofemoral Ligament Reconstruction Combined with Tibial Tuberosity Transfer in the Treatment of Patellofemoral Instability
Tarek BOUTEFNOUCHET ; Christopher DOWNHAM ; James BASSETT ; Peter THOMPSON ; Andrew SPROWSON
The Journal of Korean Knee Society 2016;28(2):99-109
A systematic review of the literature was undertaken to evaluate the efficacy of medial patellofemoral ligament (MPFL) reconstruction combined with tibial tuberosity transfer (TTT) in the treatment of patellofemoral instability. Using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, a systematic search was carried out to identify and review the published literature pertinent to MFPL reconstruction combined with TTT. Relevant studies were critically appraised with narrative data synthesis. Studies that met the eligibility criteria were suitable for appraisal and consisted of case series and therapeutic series (levels IV & III). All studies had inherent variations in outcomes reporting and limited follow-up. Combined treatment offers restoration of normal anatomy, thus adding clinical value to the currently recommended anatomic approach to MPFL reconstruction. Nevertheless, the current body of evidence does not determine the threshold at which patellofemoral axis requires the need for adjunctive distal realignment as opposed to MPFL reconstruction alone. This review highlighted numerous recurring limitations in the conduct and presentation of the studies, which inadvertently mitigated the interpretation of their results. Future priority should be awarded to larger randomised controlled trials utilising validated patient reported outcome measures.
Awards and Prizes
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Follow-Up Studies
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Humans
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Ligaments
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Outcome Assessment (Health Care)
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Patellar Dislocation
2.Multiple Residues in the P-Region and M2 of Murine Kir 2.1 Regulate Blockage by External Ba2+.
Young Mee LEE ; Gareth A THOMPSON ; Ian ASHMOLE ; Mark LEYLAND ; Insuk SO ; Peter R STANFIELD
The Korean Journal of Physiology and Pharmacology 2009;13(1):61-70
We have examined the effects of certain mutations of the selectivity filter and of the membrane helix M2 on Ba2+ blockage of the inward rectifier potassium channel, Kir 2.1. We expressed mutant and wild type murine Kir 2.1 in Chinese hamster ovary (CHO) cells and used the whole cell patch-clamp technique to record K+ currents in the absence and presence of externally applied Ba2+. Wild type Kir2.1 was blocked by externally applied Ba2+ in a voltage and concentration dependent manner. Mutants of Y145 in the selectivity filter showed little change in the kinetics of Ba2+ blockage. The estimated Kd(0) was 108micrometer for Kir2.1 wild type, 124micrometer for a concatameric WT-Y145V dimer, 109micrometer for a WT-Y145L dimer, and 267micrometer for Y145F. Mutant channels T141A and S165L exhibit a reduced affinity together with a large reduction in the rate of blockage. In S165L, blockage proceeds with a double exponential time course, suggestive of more than one blocking site. The double mutation T141A/S165L dramatically reduced affinity for Ba2+, also showing two components with very different time courses. Mutants D172K and D172R (lining the central, aqueous cavity of the channel) showed both a decreased affinity to Ba2+ and a decrease in the on transition rate constant (kon). These results imply that residues stabilising the cytoplasmic end of the selectivity filter (T141, S165) and in the central cavity (D172) are major determinants of high affinity Ba2+ blockage in Kir 2.1.
Animals
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Cricetinae
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Cricetulus
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Cytoplasm
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Female
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Kinetics
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Membranes
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Ovary
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Patch-Clamp Techniques
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Potassium Channels
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Potassium Channels, Inwardly Rectifying