Patellar instability Colvin, Alexis Chiang; West, Robin V
Journal of bone and joint surgery. American volume
90, Issue:
12
Journal Article
Peer reviewed
Recurrent patellar instability can result from osseous abnormalities, such as patella alta, a distance of >20 mm between the tibial tubercle and the trochlear groove, and trochlear dysplasia, or it ...can result from soft-tissue abnormalities, such as a torn medial patellofemoral ligament or a weakened vastus medialis obliquus. Nonoperative treatment includes physical therapy, focusing on strengthening of the gluteal muscles and the vastus medialis obliquus, and patellar taping or bracing. Acute medial-sided repair may be indicated when there is an osteochondral fracture fragment or a retinacular injury. The recent literature does not support the use of an isolated lateral release for the treatment of patellar instability. A patient with recurrent instability, with or without trochlear dysplasia, who has a normal tibial tubercle-trochlear groove distance and a normal patellar height may be a candidate for a reconstruction of the medial patellofemoral ligament with autograft or allograft. Distal realignment procedures are used in patients who have an increased tibial tubercle-trochlear groove distance or patella alta. The degree of anteriorization, distalization, and/or medialization depends on associated arthrosis of the lateral patellar facet and the presence of patella alta. Associated medial or proximal patellar chondrosis is a contraindication to distal realignment because of the potential to overload tissues that have already undergone degeneration.
Background:
An anterior cruciate ligament (ACL) injury greatly increases the risk for premature knee osteoarthritis (OA). Improved diagnosis and staging of early disease are needed to develop ...strategies to delay or prevent disabling OA.
Purpose:
Novel magnetic resonance imaging (MRI) ultrashort echo time (UTE)–T2* mapping was evaluated against clinical metrics of cartilage health in cross-sectional and longitudinal studies of human participants before and after ACL reconstruction (ACLR) to show reversible deep subsurface cartilage and meniscus matrix changes.
Study Design:
Cohort study (diagnosis/prognosis); Level of evidence, 2.
Methods:
Forty-two participants (31 undergoing anatomic ACLR; 11 uninjured) underwent 3-T MRI inclusive of a sequence capturing short and ultrashort T2 signals. An arthroscopic examination of the medial meniscus was performed, and modified Outerbridge grades were assigned to the central and posterior medial femoral condyle (cMFC and pMFC, respectively) of ACL-reconstructed patients. Two years after ACLR, 16 patients underwent the same 3-T MRI. UTE-T2* maps were generated for the posterior medial meniscus (pMM), cMFC, pMFC, and medial tibial plateau (MTP). Cross-sectional evaluations of UTE-T2* and arthroscopic data along with longitudinal analyses of UTE-T2* changes were performed.
Results:
Arthroscopic grades showed that 74% (23/31) of ACL-reconstructed patients had intact cMFC cartilage (Outerbridge grade 0 and 1) and that 90% (28/31) were Outerbridge grade 0 to 2. UTE-T2* values in deep cMFC and pMFC cartilage varied significantly with injury status and arthroscopic grade (Outerbridge grade 0-2: n = 39; P = .03 and .04, respectively). Pairwise comparisons showed UTE-T2* differences between uninjured controls (n = 11) and patients with arthroscopic Outerbridge grade 0 for the cMFC (n = 12; P = .01) and arthroscopic Outerbridge grade 1 for the pMFC (n = 11; P = .01) only and not individually between arthroscopic Outerbridge grade 0, 1, and 2 of ACL-reconstructed patients (P > .05). Before ACLR, UTE-T2* values of deep cMFC and pMFC cartilage of ACL-reconstructed patients were a respective 43% and 46% higher than those of uninjured controls (14.1 ± 5.5 vs 9.9 ± 2.3 milliseconds cMFC and 17.4 ± 7.0 vs 11.9 ± 2.4 milliseconds pMFC, respectively; P = .02 for both). In longitudinal analyses, preoperative elevations in UTE-T2* values in deep pMFC cartilage and the pMM in those with clinically intact menisci decreased to levels similar to those in uninjured controls (P = .02 and .005, respectively), suggestive of healing. No decrease in UTE-T2* values for the MFC and new elevation in UTE-T2* values for the submeniscus MTP were observed in those with meniscus tears.
Conclusion:
This study shows that novel UTE-T2* mapping demonstrates changes in cartilage deep tissue health according to joint injury status as well as a potential for articular cartilage and menisci to heal deep tissue injuries. Further clinical studies of UTE-T2* mapping are needed to determine if it can be used to identify joints at risk for rapid degeneration and to monitor effects of new treatments to delay or prevent the development of OA.
In this article, I explore media representations in a UK-owned online news outlet of the North Korean situation, drawing on the work of Michel Foucault and Stuart Hall as a means of analyzing the ...discursive formations through which representations of state criminality, associated victimization, and normative transgressions are presented to the audience. I argue that the strategy of encoding the discourse leads to the emptying out of cultural and historical contexts. In many cases, reports "refill" this void with appeals to lifeworld interpretations that resonate more with audiences' historical consciousness than depict the reality of North Korea. I conclude by suggesting that "emptied" reports may serve the function of creating a sense of ontological security that conditions audiences' decoding of the media texts.
This book brings together academics, legal practitioners and activists with a wide range of pro-choice, pro-life and other views to explore the possibilities for cultural, philosophical, moral and ...political common ground on the subjects of abortion and reproductive justice more generally. It aims to rethink polarized positions on sexuality, morality, religion and law, in relation to abortion, as a way of laying the groundwork for productive and collaborative dialogue. Edited by a leading figure on gender issues and emerging voices in the quest for reproductive justice - a broad concept that encompasses the interests of men, women and children alike - the contributions both search for 'common ground' between opposing positions in our struggles around abortion, and seek to bring balance to these contentious debates. The book will be valuable to anyone interested in law and society, gender and religious studies and philosophy and theory of law.
Successfully learning and remembering people's names is a challenging memory task for adults of all ages, and this already difficult social skill worsens with age, even in normative “healthy” aging. ...The own-age bias, a type of in-group bias, could affect the difficulty of this task across age. Past evidence supports an own-age bias in face processing, wherein individuals preferably attend to and better recognize faces of members of their own age group. However, the own-age bias has not been examined previously in relation to explicit face-name associative encoding and subsequent name retrieval, despite the importance of this social skill. Using behavioral and eye-tracking methodology, this cross-sectional research investigated the own-age bias for name memory (recognition and recall) and visual attention (fixation count, looking time, and normalized pupil size) when learning novel face-name pairs. Younger adult (n = 90) and older adult (n = 84) participants completed a face-name association task that tested name memory for younger and older female and male faces, while eye-tracking data were recorded. The visual attention variables taken from the eye-tracking data showed significant age-of-face effects at both encoding and retrieval, but no overall own-age bias in attention. Both younger and older participants showed an own-age bias in name recall with better memory for names paired with faces of their own age, as compared to other-aged faces. This cross-over effect for name memory suggests that memory for information with high social and affective relevance to the individual may be relatively spared in aging, despite overall age-related declines in memory performance.
•Evidence for own-age bias in adults extended from face recognition to name memory.•Younger and older adults better remember names paired with own- vs. other-age faces.•Greater visual attention to younger vs. older faces for younger and older adult.
Background This study was designed to investigate differences in recovery in male and female soccer athletes.
Hypotheses Soccer players with a history of concussion will perform worse on ...neurocognitive testing than players without a history of
concussion. Furthermore, female athletes will demonstrate poorer performance on neurocognitive testing than male athletes.
Study Design Cohort study (prognosis): Level of evidence, 2.
Methods Computer-based neuropsychological testing using reaction time, memory, and visual motor-speed composite scores of the ImPACT
test battery was performed postconcussion in soccer players ranging in age from 8 to 24 years (N = 234; 141 females, 93 males).
A multivariate analysis of variance was conducted to examine group differences in neurocognitive performance between male
and female athletes with and without a history of concussion.
Results Soccer players with a history of at least 1 previous concussion performed significantly worse on ImPACT than those who had
not sustained a prior concussion ( F = 2.92, P =.03). In addition, female soccer players performed worse on neurocognitive testing ( F = 2.72, P =.05) and also reported more symptoms ( F = 20.1, P =.00001) than male soccer players. There was no significant difference in body mass index between male and female players
( F =.04, P =.85).
Conclusion A history of concussion and gender may account for significant differences in postconcussive neurocognitive test scores in
soccer players and may play a role in determining recovery. These differences do not appear to reflect differences in mass
between genders and may be related to other gender-specific factors that deserve further study.
Background:
The quadriceps tendon is a versatile graft option, and the clinical implications of a quadriceps tendon harvest need to be further defined.
Purpose:
To review surgical considerations for ...the safe harvest of a quadriceps tendon autograft for anterior cruciate ligament (ACL) reconstruction, with a focus on the risk of patellar fractures.
Study Design:
Case series; Level of evidence, 4.
Methods:
A series of 57 patients underwent ACL reconstruction with a quadriceps tendon autograft with a patellar bone block from March 2011 to December 2012 at a single institution. Patients who sustained a patellar fracture were identified. The clinical course for each patient was reviewed with International Knee Documentation Committee (IKDC) subjective knee form scores through 2-year follow-up.
Results:
The incidence of patellar fractures was 3.5% intraoperatively and 8.8% at 2 years. This included 2 intraoperative fractures, 1 fracture during strength testing, and 2 occult fractures detected on computed tomography (CT) performed 6 months postoperatively for research purposes in asymptomatic participants. For the 5 patients with a patellar fracture with 24-month follow-up, the IKDC scores were 91.95, 91.95, 100.00, 100.00, and 64.37.
Conclusion:
Careful consideration of the quadriceps tendon and patellar anatomy is needed to safely harvest the bone plug from the superior pole of the patella. The consequences of a quadriceps tendon autograft harvest, specifically with regard to the risks associated with fractures of the patella during the harvest, demand full consideration. Postoperative imaging with CT may identify abnormalities in patients who are otherwise asymptomatic.
Almost self-fulfilling, commonly held negative stereotypes about old age and memory can impair older adults' episodic memory performance, due to age-based stereotype threat or self-stereotyping ...effects. Research studies demonstrating detrimental impacts of age stereotypes on memory performance are generally conducted in research laboratories or medical settings, which often underestimate memory abilities of older adults. To better understand the "real world" impact of negative age and memory stereotypes on episodic memory, the present research tested story recall performance of late middle-aged and older adults (
= 51) following a naturalistic age stereotype manipulation, wherein every day, newspaper-style materials (comics and puzzles) were either embedded with negative age and memory stereotype stimuli (stereotype group) or neutral stimuli (control group). Furthermore, all participants were tested in favorable, familiar environments. Potential moderators of the stereotype effects, e.g., metamemory beliefs, were assessed at baseline. Current memory evaluation and subjective age, as well as perceived stereotype threat and task-related anxiety, were assessed following the stereotype manipulation as potential mechanisms of the expected stereotype effects. Results suggested a contrast effect, as the stereotype group demonstrated superior story recall performance compared to the control group. Marginally significant moderation effects by age and perceived stereotype threat indicated that stereotype rejection was present for late middle-aged adults but not older adults, indicative of stereotype lift, and for individuals who reported low and average, but not high, levels of perceived stereotype threat. Additionally, a trend suggested more positive memory evaluation for those in the stereotype group who reported awareness of the stereotype stimuli than those who did not notice the stimuli. These results are consistent with other research demonstrating benefits to memory performance in adulthood based on motivational and contextual factors, such as using relevant memory materials and testing in favorable conditions. Moreover, the results of this study contribute to our understanding of individuals' responses to different types of stereotype stimuli, and the differential impact of stereotype manipulations that are subtle versus blatant. Individuals were motivated to counteract negative stereotype effects when conditions were supportive, stereotype presentations were naturalistic, and personal beliefs were positive.
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