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Hoshino Y.,University of Pittsburgh | Hoshino Y.,Kobe University | Araujo P.,University of Pittsburgh | Ahlden M.,Gothenburg University | And 6 more authors.
Knee Surgery, Sports Traumatology, Arthroscopy | Year: 2012

Purpose: The variability of the pivot shift test techniques greatly interferes with achieving a quantitative and generally comparable measurement. The purpose of this study was to compare the variation of the quantitative pivot shift measurements with different surgeons' preferred techniques to a standardized technique. The hypothesis was that standardizing the pivot shift test would improve consistency in the quantitative evaluation when compared with surgeon-specific techniques. Methods: A whole lower body cadaveric specimen was prepared to have a low-grade pivot shift on one side and high-grade pivot shift on the other side. Twelve expert surgeons performed the pivot shift test using (1) their preferred technique and (2) a standardized technique. Electromagnetic tracking was utilized to measure anterior tibial translation and acceleration of the reduction during the pivot shift test. The variation of the measurement was compared between the surgeons' preferred technique and the standardized technique. Results: The anterior tibial translation during pivot shift test was similar between using surgeons' preferred technique (left 24.0 ± 4.3 mm; right 15.5 ± 3.8 mm) and using standardized technique (left 25.1 ± 3.2 mm; right 15.6 ± 4.0 mm; n. s.). However, the variation in acceleration was significantly smaller with the standardized technique (left 3.0 ± 1. 3 mm/s 2; right 2.5 ± 0.7 mm/s 2) compared with the surgeons' preferred technique (left 4.3 ± 3.3 mm/s 2; right 3.4 ± 2.3 mm/s 2; both P < 0.01). Conclusion: Standardizing the pivot shift test maneuver provides a more consistent quantitative evaluation and may be helpful in designing future multicenter clinical outcome trials. Level of evidence: Diagnostic study, Level I. © 2011 Springer-Verlag. Source

Facchini A.,University of Bologna | Stanic I.,University of Bologna | Cetrullo S.,University of Bologna | Borzi R.M.,Laboratorio Of Immunoreumatologia E Rigenerazione Tissutale | And 2 more authors.
Journal of Cellular Physiology | Year: 2011

Chondrocyte cell death can contribute to cartilage degeneration in articular diseases, such as osteoarthritis (OA). Sulforaphane (SFN), a natural compound derived from cruciferous aliment, is well known as an anti-carcinogen, but according to recent evidence it also shows cytoprotective effects on a variety of non-tumoral cells. Therefore we have tested the ability of SFN to protect chondrocytes from cell death in vitro. Treatment of growing monolayer cultures of human C-28/I2 chondrocytes with SFN in the low micro-molecular range for a few days, reduced cell growth without affecting cell survival or inducing apoptosis. However it decreased cell death in C-28/I2 chondrocytes exposed to stimuli previously reported to promptly trigger apoptosis, that is, the cytokine tumor necrosis factor-α (TNF) plus cycloheximide (CHX) or the polyamine analogue N 1,N 11-diethylnorspermine (DENSPM) plus CHX. In particular pre-treatment with SFN reduced effector and initiator caspase activities and the associated activation of JNK kinases. SFN exerted a cytoprotective action even versus H 2O 2, which differently from the previous stimuli induced cell death without producing an evident caspase activation. SFN pre-treatment also prevented caspase activation in three-dimensional micromass cultures of OA chondrocytes stimulated with growth-related oncogene α (GROα), a pro-apoptotic chemokine. The suppression of caspase activation in micromasses appeared to be related to the inhibition of p38 MAPK phosphorylation. In conclusion, the present work shows that low micro-molecular SFN concentrations exert pro-survival and anti-apoptotic actions and influence signaling pathways in a variety of experimental conditions employing chondrocyte cell lines and OA chondrocytes treated with a range of death stimuli. © 2010 Wiley-Liss, Inc. Source

Lopomo N.,Laboratorio Of Biomeccanica E Innovazione Tecnologica | Lopomo N.,Laboratorio Of Nanobiotecnologie Nabi | Zaffagnini S.,Laboratorio Of Biomeccanica E Innovazione Tecnologica | Amis A.A.,Imperial College London
Knee Surgery, Sports Traumatology, Arthroscopy | Year: 2013

Purpose: This study aims to identify and summarize the evidence on the biomechanical parameters and the corresponding technologies which have been used to quantify the pivot shift test during the clinical and functional assessment of anterior cruciate ligament (ACL) injury and surgical reconstruction. Methods: Searchstrategy Internet search of indexed scientific articles on the PubMed database, Web of Science and references on published manuscripts. No year restriction was used. Selection criteria Articles included were written only in English and related to search terms: "pivot shift" AND (OR "ACL"). The reviewers independently selected only those studies that included at least one quantitative parameter for the analysis of the pivot shift test, including both in vitro and in vivo analyses performed on human joint. Those studies that analysed only clinical grading were excluded from the analysis. Analysis After evaluating the methodological quality of the articles, the parameters found were summarized. Results: Six hundred and eight studies met the inclusion criteria, and finally, 68 unique studies were available for the systematic review. Quantitative results were heterogeneous. The pivot shift test has been quantified by means of 25 parameters, but most of the studies focused on anterior-posterior translations, internal-external rotation and acceleration in anterior-posterior direction. Conclusion: Several methodologies have been identified and developed to quantify pivot shift test. However, clinical professionals are still lacking a 'gold standard' method for the quantification of knee joint dynamic laxity. A widespread adoption of a standardized pivot shift manoeuvre and measurement method to allow objective comparison of the results of ACL reconstructions is therefore desirable. Further development of measurement methods is indeed required to achieve this goal in a routine clinical scenario. Level of Evidence: Systematic review of-at least-level II studies, Level II. © 2013 Springer-Verlag Berlin Heidelberg. Source

Lopomo N.,Laboratorio Of Biomeccanica E Innovazione Tecnologica | Lopomo N.,Laboratorio Of Nanobiotecnologie Nabi | Signorelli C.,Laboratorio Of Biomeccanica E Innovazione Tecnologica | Signorelli C.,Polytechnic of Milan | And 6 more authors.
International Orthopaedics | Year: 2014

Purpose: Despite the overall success of the surgical anterior cruciate ligament (ACL) reconstruction, some patients still present with instability symptoms even after the surgery, mainly due to the presence of associated lesions. At present, the pivot shift test has been reported to be the benchmark to assess rotatory knee laxity. The purpose of this study was to quantitatively evaluate rotatory knee laxity at time-zero in order to determine whether detected post-reconstruction laxity was predictable by its value measured before the reconstruction, which was hypothized to be influenced by the presence of associated lesions. Methods: Rotatory knee laxity was retrospectively analysed in 42 patients, including two different ACL reconstructions. The maximal anterior displacement and the absolute value of the posterior acceleration reached during the reduction of the tibial lateral compartment were intra-operatively acquired by using a navigation system and identified as discriminating parameters. For each parameter, statistical linear regression analysis (line slope and intercept)was performed between preand post-reconstruction values. Results: No statistically significant influence of the initial posterior acceleration on the post-reconstruction outcome was found (line slope, p>0.05), although a statistically significant line intercept was indeed identified (p<0.001). A statistically significant influence on the surgery outcome was instead found for the initial value of the anterior tibial displacement (line slope=0.39, p =0.004), meaning that, on average, about 40% of the post-reconstruction lateral compartment displacement could be explained by the corresponding pre-reconstruction value. Both of these findings highlighted the importance of intra-operative quantification of rotatory knee laxity to identify correct indications for the surgery. Conclusions: This study provided important implications for the future possibility of defining a quantifying tool able to assess rotatory knee laxity during ACL reconstruction. This could allow detection of additional injuries to secondary restraints by easily performing rotatory knee laxity tests, which in turn could reduce post-surgical recurrence of knee instability. © Springer-Verlag 2014. Source

Lopomo N.,Laboratorio Of Biomeccanica E Innovazione Tecnologica | Lopomo N.,Laboratorio Of Nanobiotecnologie Nabi | Signorelli C.,Laboratorio Of Biomeccanica E Innovazione Tecnologica | Signorelli C.,Polytechnic of Milan | And 4 more authors.
Knee Surgery, Sports Traumatology, Arthroscopy | Year: 2012

Purpose: The pivot-shift phenomenon has been identified to be one of the essential signs of functional anterior cruciate ligament (ACL) insufficiency. However, the pivot-shift test remains a surgeon-subjective examination, lacking a general recognized quantitative measurement. The goal of the present study was to validate the use of an inertial sensor for quantifying the pivot-shift test, using a commercial navigation system. Methods: An expert surgeon intra-operatively performed the pivot-shift test on 15 consecutive patients before ACL reconstruction. A single accelerometer and a commercial navigation system simultaneously acquired limb kinematics. An additional optical tracker mounted on the accelerometer allowed following sensor movements. Anteroposterior (a-p) tibial acceleration obtained with the navigation system was compared with three-dimensional (3D) acceleration acquired by the accelerometer. The effect of skin artifacts and test-retest positioning were estimated. Repeatability of the acceleration parameter and waveform was analyzed. Correlation between the two measurements was also assessed. Results: Average root mean square (RMS) error in test-retest positioning reported a good value of 5.5 ± 2.9 mm. Mean RMS displacement due to soft tissue artifacts was 4.9 ± 2.6 mm. The analysis of acceleration range repetitions reported a good intra-tester repeatability (Cronbach's alpha = 0.86). Inter-patients similarity analysis showed a mean acceleration waveform correlation of 0.88 ± 0.14. The acceleration ranges demonstrated a good positive correlation between the two measurements (rs = 0.72, P < 0.05). Conclusion: This study showed good reliability of the new device and good correlation with the navigation system results. Therefore, the accelerometer is a valid method to assess dynamic joint laxity. Level of evidence: II. © 2012 Springer-Verlag. Source

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