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Bryan T. Kelly - One of the best experts on this subject based on the ideXlab platform.
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Patient Characteristics and Early Functional Outcomes of Combined Arthroscopic Labral Refixation and Periacetabular Osteotomy for Symptomatic Acetabular Dysplasia
The American journal of sports medicine, 2016Co-Authors: Benjamin F. Ricciardi, Stephanie W. Mayer, Kara G. Fields, Catherine Wentzel, Bryan T. Kelly, Ernest L. SinkAbstract:Background:Symptomatic labral tears are common in patients with acetabular dysplasia; however, optimal treatment of the labrum remains controversial.Purpose:To present patient characteristics and early functional outcomes associated with combined arthroscopic labral Refixation and Bernese periacetabular osteotomy (PAO) for symptomatic acetabular dysplasia with a displaced labral tear from the acetabular rim.Study Design:Cohort study; Level of evidence, 3.Methods:Patients undergoing PAO from a single-center prospective hip preservation registry were eligible (N = 73 patients; mean clinical follow-up, 23 months). Indications for combined arthroscopic labral Refixation included symptomatic labral injury and MRI findings suggestive of labral detachment from the acetabular rim indicating a repairable tear. The study group consisted of patients undergoing combined arthroscopic labral Refixation and PAO (scope/PAO group: n = 21 patients). Patients undergoing PAO alone (PAO group: n = 52 patients) were included a...
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Clinical and Morphologic Factors Associated with Suture Anchor Refixation of Labral Tears in the Hip
HSS Journal ®, 2014Co-Authors: John A. Ruder, Erin Magennis, Anil S. Ranawat, Bryan T. KellyAbstract:Background The acetabular labrum is critical to hip function. Surgical options for treatment of a damaged labrum include removal, debridement, and Refixation using suture anchors. Questions/Purposes The purpose of this study is to determine if certain patient demographic and osseous morphological factors result in increased labral damage requiring Refixation. Methods Data was collected prospectively from a consecutive series of 334 procedures performed from August 2010 to June 2011 for femoroacetabular impingement. Demographic data, including age, sex, and race, was collected from patient charts. Three-dimensional (3D) CT scans were reviewed to retrieve alpha angles, acetabular version, femoral version, and lateral center edge angle on the symptomatic hip. Results In 238 (71.3%) of the procedures, the labrum required Refixation using suture anchors with a mean of 2.74 anchors being used. Of males, 78.8% required suture anchors and 62.3% of females required suture anchors. Among procedures requiring suture anchors, significantly more suture anchors were used in males (2.92) than females (2.47). Regression analysis showed a positive association between alpha angle, acetabular retroversion at 1 and 2 o’clock, and the number of suture anchors used. The mean alpha angle in the cohort that required suture anchors (63.1°) was significantly greater than the cohort that did not (59.4°). Conclusion This study found femoral deformities to contribute more to labral damage than acetabular deformities and highlighted the importance of preoperative 3D CT scans. This study provides demographic and morphologic factors to review preoperatively to evaluate if extensive labral damage is present and if suture anchor Refixation will be required.
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Clinical and morphologic factors associated with suture anchor Refixation of labral tears in the hip.
HSS journal : the musculoskeletal journal of Hospital for Special Surgery, 2013Co-Authors: John Ruder, Anil S. Ranawat, Erin Magennis, Bryan T. KellyAbstract:Background The acetabular labrum is critical to hip function. Surgical options for treatment of a damaged labrum include removal, debridement, and Refixation using suture anchors.
Cees Van Leeuwen - One of the best experts on this subject based on the ideXlab platform.
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Neural correlates of task-related Refixation behavior.
Vision research, 2020Co-Authors: Radha Nila Meghanathan, Cees Van Leeuwen, Marcello Giannini, Andrey R. NikolaevAbstract:Eye movement research has shown that attention shifts from the currently fixated location to the next before a saccade is executed. We investigated whether the cost of the attention shift depends on higher-order processing at the time of fixation, in particular on visual working memory load differences between fixations and Refixations on task-relevant items. The attention shift is reflected in EEG activity in the saccade-related potential (SRP). In a free viewing task involving visual search and memorization of multiple targets amongst distractors, we compared the SRP in first fixations versus Refixations on targets and distractors. The task-relevance of targets implies that more information will be loaded in memory (e.g. both identity and location) than for distractors (e.g. location only). First fixations will involve greater memory load than Refixations, since first fixations involve loading of new items, while Refixations involve rehearsal of previously visited items. The SRP in the interval preceding the saccade away from a target or distractor revealed that saccade preparation is affected by task-relevance and Refixation behavior. For task-relevant items only, we found longer fixation duration and higher SRP amplitudes for first fixations than for Refixations over the occipital region and the opposite effect over the frontal region. Our findings provide first neurophysiological evidence that working memory loading of task-relevant information at fixation affects saccade planning.
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Neural Correlates of Task-related Refixation Behaviour
2019Co-Authors: Radha Nila Meghanathan, Cees Van Leeuwen, Marcello Giannini, Andrey R. NikolaevAbstract:Abstract Information uptake during scene viewing under free viewing conditions is crucially determined by the scanning plan. This plan is determined both by top-down and bottom-up factors. To capture top-down factors affecting saccade planning, we compared EEG between first fixations and Refixations on items varying in task-relevance. First fixations and Refixations impose different working memory costs because first fixations involve encoding of new items whereas Refixations involve rehearsal of existing items in working memory. These memory requirements also differ with the task-relevance of the item being encoded. Together, these two factors of task-relevance and memory processes related to Refixation behavior would affect saccade planning. In a visual task involving search and memorization of multiple targets, we compared saccade-related potentials (SRPs) between first fixations and Refixations for task-relevant (target) and task-irrelevant (distractor) items. We assessed the interval preceding a saccade away from the fixation of interest. Studying this presaccadic interval revealed how mechanisms related to saccade preparation are affected by task-relevance and Refixation behavior. We found higher SRP amplitudes for first fixations than Refixations over the occipital region for task-relevant items only. Our findings indicate that saccade planning is modulated by both task-relevance of an item and working memory load.
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Revising the scanning plan for continued visual exploration: the neurophysiology of Refixation-related behavior
2019Co-Authors: Andrey R. Nikolaev, Radha Nila Meghanathan, Marcello Giannini, Cees Van LeeuwenAbstract:Abstract Regarding the continued exploration of a visual scene, little is known about how far ahead we plan our eye-movements. We propose that when the eyes return to a previously visited location, this Refixation may have already been planned at the initial visit, i.e., at the precursor fixation. Precursor fixations are effective markers of strategic locations for later scrutiny. This implies visual processing is enhanced at precursor fixations. Moreover, since marking involves updating the scanning plan, activation of oculomotor control routines may also be expected. The opposite is expected when Refixations are only made to recover information lost or missed during scanning. However, the eye-movement literature so far has ignored precursor fixations. Using EEG-eye movement co-registration in a natural viewing task, we analyzed fixation-related EEG in precursor fixations, ordinary fixations, and Refixations. The analysis crucially involved matching potentially confounding eye movement characteristics between fixation types. In precursor fixations, amplitude of fixation-related potentials over posterior areas was increased and EEG alpha power over frontal areas was decreased, compared to ordinary fixations. These findings, respectively, indicate enhanced rather than deficient visual processing at precursor fixations and enhanced oculomotor control activity. Our results question the major role of Refixations as compensating for lost information and support the proposal of periodic updating of saccade planning at precursor fixations in the course of visual exploration.
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Refixation patterns reveal memory-encoding strategies in free viewing.
Attention perception & psychophysics, 2019Co-Authors: Radha Nila Meghanathan, Andrey R. Nikolaev, Cees Van LeeuwenAbstract:We investigated visual working memory encoding across saccadic eye movements, focusing our analysis on Refixation behavior. Over 10-s periods, participants performed a visual search for three, four, or five targets and remembered their orientations for a subsequent change-detection task. In 50% of the trials, one of the targets had its orientation changed. From the visual search period, we scored three types of Refixations and applied measures for quantifying eye-fixation recurrence patterns. Repeated fixations on the same regions as well as repeated fixation patterns increased with memory load. Correct change detection was associated with more Refixations on targets and less on distractors, with increased frequency of recurrence, and with longer intervals between Refixations. The results are in accordance with the view that patterns of eye movement are an integral part of visual working memory representation.
Andrey R. Nikolaev - One of the best experts on this subject based on the ideXlab platform.
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Neural correlates of task-related Refixation behavior.
Vision research, 2020Co-Authors: Radha Nila Meghanathan, Cees Van Leeuwen, Marcello Giannini, Andrey R. NikolaevAbstract:Eye movement research has shown that attention shifts from the currently fixated location to the next before a saccade is executed. We investigated whether the cost of the attention shift depends on higher-order processing at the time of fixation, in particular on visual working memory load differences between fixations and Refixations on task-relevant items. The attention shift is reflected in EEG activity in the saccade-related potential (SRP). In a free viewing task involving visual search and memorization of multiple targets amongst distractors, we compared the SRP in first fixations versus Refixations on targets and distractors. The task-relevance of targets implies that more information will be loaded in memory (e.g. both identity and location) than for distractors (e.g. location only). First fixations will involve greater memory load than Refixations, since first fixations involve loading of new items, while Refixations involve rehearsal of previously visited items. The SRP in the interval preceding the saccade away from a target or distractor revealed that saccade preparation is affected by task-relevance and Refixation behavior. For task-relevant items only, we found longer fixation duration and higher SRP amplitudes for first fixations than for Refixations over the occipital region and the opposite effect over the frontal region. Our findings provide first neurophysiological evidence that working memory loading of task-relevant information at fixation affects saccade planning.
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Neural Correlates of Task-related Refixation Behaviour
2019Co-Authors: Radha Nila Meghanathan, Cees Van Leeuwen, Marcello Giannini, Andrey R. NikolaevAbstract:Abstract Information uptake during scene viewing under free viewing conditions is crucially determined by the scanning plan. This plan is determined both by top-down and bottom-up factors. To capture top-down factors affecting saccade planning, we compared EEG between first fixations and Refixations on items varying in task-relevance. First fixations and Refixations impose different working memory costs because first fixations involve encoding of new items whereas Refixations involve rehearsal of existing items in working memory. These memory requirements also differ with the task-relevance of the item being encoded. Together, these two factors of task-relevance and memory processes related to Refixation behavior would affect saccade planning. In a visual task involving search and memorization of multiple targets, we compared saccade-related potentials (SRPs) between first fixations and Refixations for task-relevant (target) and task-irrelevant (distractor) items. We assessed the interval preceding a saccade away from the fixation of interest. Studying this presaccadic interval revealed how mechanisms related to saccade preparation are affected by task-relevance and Refixation behavior. We found higher SRP amplitudes for first fixations than Refixations over the occipital region for task-relevant items only. Our findings indicate that saccade planning is modulated by both task-relevance of an item and working memory load.
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Revising the scanning plan for continued visual exploration: the neurophysiology of Refixation-related behavior
2019Co-Authors: Andrey R. Nikolaev, Radha Nila Meghanathan, Marcello Giannini, Cees Van LeeuwenAbstract:Abstract Regarding the continued exploration of a visual scene, little is known about how far ahead we plan our eye-movements. We propose that when the eyes return to a previously visited location, this Refixation may have already been planned at the initial visit, i.e., at the precursor fixation. Precursor fixations are effective markers of strategic locations for later scrutiny. This implies visual processing is enhanced at precursor fixations. Moreover, since marking involves updating the scanning plan, activation of oculomotor control routines may also be expected. The opposite is expected when Refixations are only made to recover information lost or missed during scanning. However, the eye-movement literature so far has ignored precursor fixations. Using EEG-eye movement co-registration in a natural viewing task, we analyzed fixation-related EEG in precursor fixations, ordinary fixations, and Refixations. The analysis crucially involved matching potentially confounding eye movement characteristics between fixation types. In precursor fixations, amplitude of fixation-related potentials over posterior areas was increased and EEG alpha power over frontal areas was decreased, compared to ordinary fixations. These findings, respectively, indicate enhanced rather than deficient visual processing at precursor fixations and enhanced oculomotor control activity. Our results question the major role of Refixations as compensating for lost information and support the proposal of periodic updating of saccade planning at precursor fixations in the course of visual exploration.
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Refixation patterns reveal memory-encoding strategies in free viewing.
Attention perception & psychophysics, 2019Co-Authors: Radha Nila Meghanathan, Andrey R. Nikolaev, Cees Van LeeuwenAbstract:We investigated visual working memory encoding across saccadic eye movements, focusing our analysis on Refixation behavior. Over 10-s periods, participants performed a visual search for three, four, or five targets and remembered their orientations for a subsequent change-detection task. In 50% of the trials, one of the targets had its orientation changed. From the visual search period, we scored three types of Refixations and applied measures for quantifying eye-fixation recurrence patterns. Repeated fixations on the same regions as well as repeated fixation patterns increased with memory load. Correct change detection was associated with more Refixations on targets and less on distractors, with increased frequency of recurrence, and with longer intervals between Refixations. The results are in accordance with the view that patterns of eye movement are an integral part of visual working memory representation.
Radha Nila Meghanathan - One of the best experts on this subject based on the ideXlab platform.
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Neural correlates of task-related Refixation behavior.
Vision research, 2020Co-Authors: Radha Nila Meghanathan, Cees Van Leeuwen, Marcello Giannini, Andrey R. NikolaevAbstract:Eye movement research has shown that attention shifts from the currently fixated location to the next before a saccade is executed. We investigated whether the cost of the attention shift depends on higher-order processing at the time of fixation, in particular on visual working memory load differences between fixations and Refixations on task-relevant items. The attention shift is reflected in EEG activity in the saccade-related potential (SRP). In a free viewing task involving visual search and memorization of multiple targets amongst distractors, we compared the SRP in first fixations versus Refixations on targets and distractors. The task-relevance of targets implies that more information will be loaded in memory (e.g. both identity and location) than for distractors (e.g. location only). First fixations will involve greater memory load than Refixations, since first fixations involve loading of new items, while Refixations involve rehearsal of previously visited items. The SRP in the interval preceding the saccade away from a target or distractor revealed that saccade preparation is affected by task-relevance and Refixation behavior. For task-relevant items only, we found longer fixation duration and higher SRP amplitudes for first fixations than for Refixations over the occipital region and the opposite effect over the frontal region. Our findings provide first neurophysiological evidence that working memory loading of task-relevant information at fixation affects saccade planning.
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Neural Correlates of Task-related Refixation Behaviour
2019Co-Authors: Radha Nila Meghanathan, Cees Van Leeuwen, Marcello Giannini, Andrey R. NikolaevAbstract:Abstract Information uptake during scene viewing under free viewing conditions is crucially determined by the scanning plan. This plan is determined both by top-down and bottom-up factors. To capture top-down factors affecting saccade planning, we compared EEG between first fixations and Refixations on items varying in task-relevance. First fixations and Refixations impose different working memory costs because first fixations involve encoding of new items whereas Refixations involve rehearsal of existing items in working memory. These memory requirements also differ with the task-relevance of the item being encoded. Together, these two factors of task-relevance and memory processes related to Refixation behavior would affect saccade planning. In a visual task involving search and memorization of multiple targets, we compared saccade-related potentials (SRPs) between first fixations and Refixations for task-relevant (target) and task-irrelevant (distractor) items. We assessed the interval preceding a saccade away from the fixation of interest. Studying this presaccadic interval revealed how mechanisms related to saccade preparation are affected by task-relevance and Refixation behavior. We found higher SRP amplitudes for first fixations than Refixations over the occipital region for task-relevant items only. Our findings indicate that saccade planning is modulated by both task-relevance of an item and working memory load.
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Revising the scanning plan for continued visual exploration: the neurophysiology of Refixation-related behavior
2019Co-Authors: Andrey R. Nikolaev, Radha Nila Meghanathan, Marcello Giannini, Cees Van LeeuwenAbstract:Abstract Regarding the continued exploration of a visual scene, little is known about how far ahead we plan our eye-movements. We propose that when the eyes return to a previously visited location, this Refixation may have already been planned at the initial visit, i.e., at the precursor fixation. Precursor fixations are effective markers of strategic locations for later scrutiny. This implies visual processing is enhanced at precursor fixations. Moreover, since marking involves updating the scanning plan, activation of oculomotor control routines may also be expected. The opposite is expected when Refixations are only made to recover information lost or missed during scanning. However, the eye-movement literature so far has ignored precursor fixations. Using EEG-eye movement co-registration in a natural viewing task, we analyzed fixation-related EEG in precursor fixations, ordinary fixations, and Refixations. The analysis crucially involved matching potentially confounding eye movement characteristics between fixation types. In precursor fixations, amplitude of fixation-related potentials over posterior areas was increased and EEG alpha power over frontal areas was decreased, compared to ordinary fixations. These findings, respectively, indicate enhanced rather than deficient visual processing at precursor fixations and enhanced oculomotor control activity. Our results question the major role of Refixations as compensating for lost information and support the proposal of periodic updating of saccade planning at precursor fixations in the course of visual exploration.
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Refixation patterns reveal memory-encoding strategies in free viewing.
Attention perception & psychophysics, 2019Co-Authors: Radha Nila Meghanathan, Andrey R. Nikolaev, Cees Van LeeuwenAbstract:We investigated visual working memory encoding across saccadic eye movements, focusing our analysis on Refixation behavior. Over 10-s periods, participants performed a visual search for three, four, or five targets and remembered their orientations for a subsequent change-detection task. In 50% of the trials, one of the targets had its orientation changed. From the visual search period, we scored three types of Refixations and applied measures for quantifying eye-fixation recurrence patterns. Repeated fixations on the same regions as well as repeated fixation patterns increased with memory load. Correct change detection was associated with more Refixations on targets and less on distractors, with increased frequency of recurrence, and with longer intervals between Refixations. The results are in accordance with the view that patterns of eye movement are an integral part of visual working memory representation.
Dean Matsuda - One of the best experts on this subject based on the ideXlab platform.
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endoscopic lesser trochanter resection with Refixation of the iliopsoas tendon for treatment of ischiofemoral impingement
Arthroscopy techniques, 2018Co-Authors: Rafael Corrales, Inaki Mediavilla, Eric Margalet, Mikel Aramberri, Jorge Murillogonzalez, Dean MatsudaAbstract:Abstract Ischiofemoral impingement is a source of hip pain derived from impingement between the lesser trochanter and the ischium. Lesser trochanter excision has been recommended for recalcitrant ischiofemoral impingement through either an anterior or posterior approach. However, neither of these approaches involves Refixation of the iliopsoas tendon. We describe an endoscopic procedure involving anterior trochanter-plasty, minimizing the risk of sciatic complications, with Refixation of the partially detached iliopsoas tendinous insertion, potentially minimizing compromise to hip flexion strength and anterior hip stability.
