Acetabular Subchondral Bone Breach During Labral Repair: Influence of Portal Location, Curved vs. Straight Drill Guides, and Drill Starting Point

Objectives: Acetabular labral tears are commonly treated with arthroscopic repair using suture anchors. Iatrogenic chondral injury has been cited as one of the more common complications during hip arthroscopy, and can occur while pre-drilling for suture anchors. Proposed factors contributing to penetration of the articular subchondral bone or the far cortex of the acetabulum include the portal utilized for drilling; the position of the drill guide relative to the acetabular rim (on rim, ON; off rim, OFF); and the use of straight (ST) versus curved (CU) drill guides. The purpose of this study was to evaluate the relative impact of these variables on drill penetration of the acetabular subchondral bone or the far cortex of the acetabulum. Methods: Sixty sawbone acetabula models were marked at the 3, 2, 1, 12, and 11 o’clock position. A Simulated anterior (AP), anterolateral (AL), and distal anterolateral accessory (DALA) portals were created. Twelve groups of five acetabula were drilled at each clock face position: ST/AP/ON; ST/AL/ON; CU/AP/ON; CU/AL/ON; ST/AP/OFF; ST/AL/OFF; CU/AP/OFF; CU/AL/OFF; ST/DALA/ON; ST/DALA/OFF; CU/DALA/ON; CU DALA/OFF. Perforations of the articular subchondral bone and far cortex of the acetabulum were recorded. Results were tabulated and analyzed to assess the relative impact of each variable both in aggregate and at each position on the clock face. Results: A total of 300 acetabular suture anchor drill holes were created on 60 acetabula 12 combinations of portal utilized (anterior, anterolateral, distal anterolateral accessory), drill guide type (curved or straight), and rim position (on rim, off rim). A total of 38/300(12.7%) drillings perforated the subchondral bone, and 45/300(15%) breach the far cortex. Drilling from the AP, AL, and DALA portal breached the articular subchondral bone 21/100 (21%), 17/100(17%), and 0/100(0%) respectively; and breached the far acetabular cortex 36/100(36%), 1/100(1%), and 8/100(8%) respectively. Drillings using a curved drill guide penetrated the subchondral bone on 14/150(9.3%) attempts and drillings using a straight drill guide penetrated the subchondral bone 33/150(22%) attempts (p=0.0025). Drillings with an “On Rim” start point breached the articular subchondral bone 29/150(19.3%) versus 9/150(6%) for drillings with an “Off Rim” start point; and breached the far acetabular cortex 21/150(14%) times versus 24/150(16%) times. Articular surface penetrations were most frequent at the 2 and 3 o’clock positons, and far cortex perforations were most frequent at the 11 and 12 o’clock positions. Conclusion: This study quantifies the relative impact of portal location, drill guide, and starting point on the acetabular rim on acetabular subchondral bone and far cortex penetration. Portal location had the highest impact, with the DALA portal noted to be the safest. Curved drill guides also reduced the number of acetabular subchondral bone penetrations. These findings can be used to influence arthroscopic technique during acetabular labral repair.

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Acetabular Subchondral and Cortical Perforation During Labral Repair With Suture Anchors: Influence of Portal Location, Curved Versus Straight Drill Guides, and Drill Starting Point

Arthroscopy The Journal of Arthroscopic and Related Surgery ◽

10.1016/j.arthro.2019.02.016 ◽

2019 ◽

Vol 35 (8) ◽

pp. 2349-2354 ◽

Cited By ~ 1

Author(s):

Guillaume D. Dumont ◽

Adam J. Money ◽

Zachary T. Thier

Keyword(s):

Labral Repair ◽

Suture Anchors ◽

Starting Point ◽

Cortical Perforation

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Crystal structure images of large gold clusters and growing crystals by HRTEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010011218x ◽

1984 ◽

Vol 42 ◽

pp. 428-429

Author(s):

L.R. Wallenberg ◽

J.-O. Bovin ◽

G. Schmid

Keyword(s):

Crystal Structure ◽

Nucleation And Growth ◽

Close Packing ◽

Gold Clusters ◽

Molecular Weight Determination ◽

Growth Mechanisms ◽

Starting Point ◽

Different Types ◽

Nucleation And Growth Mechanisms ◽

Points Of View

Metallic clusters are interesting from various points of view, e.g. as a mean of spreading expensive catalysts on a support, or following heterogeneous and homogeneous catalytic events. It is also possible to study nucleation and growth mechanisms for crystals with the cluster as known starting point.Gold-clusters containing 55 atoms were manufactured by reducing (C6H5)3PAuCl with B2H6 in benzene. The chemical composition was found to be Au9.2[P(C6H5)3]2Cl. Molecular-weight determination by means of an ultracentrifuge gave the formula Au55[P(C6H5)3]Cl6 A model was proposed from Mössbauer spectra by Schmid et al. with cubic close-packing of the 55 gold atoms in a cubeoctahedron as shown in Fig 1. The cluster is almost completely isolated from the surroundings by the twelve triphenylphosphane groups situated in each corner, and the chlorine atoms on the centre of the 3x3 square surfaces. This gives four groups of gold atoms, depending on the different types of surrounding.

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Two isoprenylated flavonoids from Dorstenia psilurus activate AMPK, stimulate glucose uptake, inhibit glucose production and lower glycemia

Biochemical Journal ◽

10.1042/bcj20190326 ◽

2019 ◽

Vol 476 (24) ◽

pp. 3687-3704 ◽

Cited By ~ 2

Author(s):

Aphrodite T. Choumessi ◽

Manuel Johanns ◽

Claire Beaufay ◽

Marie-France Herent ◽

Vincent Stroobant ◽

...

Keyword(s):

Glucose Uptake ◽

Human Cancer ◽

Glucose Production ◽

Liver Mitochondria ◽

New Drugs ◽

Structural Isomer ◽

Rat Liver Mitochondria ◽

Ionization Mass ◽

Ampk Activation ◽

Starting Point

Root extracts of a Cameroon medicinal plant, Dorstenia psilurus, were purified by screening for AMP-activated protein kinase (AMPK) activation in incubated mouse embryo fibroblasts (MEFs). Two isoprenylated flavones that activated AMPK were isolated. Compound 1 was identified as artelasticin by high-resolution electrospray ionization mass spectrometry and 2D-NMR while its structural isomer, compound 2, was isolated for the first time and differed only by the position of one double bond on one isoprenyl substituent. Treatment of MEFs with purified compound 1 or compound 2 led to rapid and robust AMPK activation at low micromolar concentrations and increased the intracellular AMP:ATP ratio. In oxygen consumption experiments on isolated rat liver mitochondria, compound 1 and compound 2 inhibited complex II of the electron transport chain and in freeze–thawed mitochondria succinate dehydrogenase was inhibited. In incubated rat skeletal muscles, both compounds activated AMPK and stimulated glucose uptake. Moreover, these effects were lost in muscles pre-incubated with AMPK inhibitor SBI-0206965, suggesting AMPK dependency. Incubation of mouse hepatocytes with compound 1 or compound 2 led to AMPK activation, but glucose production was decreased in hepatocytes from both wild-type and AMPKβ1−/− mice, suggesting that this effect was not AMPK-dependent. However, when administered intraperitoneally to high-fat diet-induced insulin-resistant mice, compound 1 and compound 2 had blood glucose-lowering effects. In addition, compound 1 and compound 2 reduced the viability of several human cancer cells in culture. The flavonoids we have identified could be a starting point for the development of new drugs to treat type 2 diabetes.

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Overview of Current Approaches to Aural Rehabilitation for Adults With Cochlear Implants

Perspectives of the ASHA Special Interest Groups ◽

10.1044/2020_persp-20-00078 ◽

2020 ◽

Vol 5 (5) ◽

pp. 1175-1187

Author(s):

Rachel Glade ◽

Erin Taylor ◽

Deborah S. Culbertson ◽

Christin Ray

Keyword(s):

Health Care ◽

Clinical Practice ◽

Cochlear Implants ◽

Practice Patterns ◽

The United States ◽

Care Providers ◽

Aural Rehabilitation ◽

Starting Point ◽

Clinical Models ◽

Hearing Health

Purpose This clinical focus article provides an overview of clinical models currently being used for the provision of comprehensive aural rehabilitation (AR) for adults with cochlear implants (CIs) in the Unites States. Method Clinical AR models utilized by hearing health care providers from nine clinics across the United States were discussed with regard to interprofessional AR practice patterns in the adult CI population. The clinical models were presented in the context of existing knowledge and gaps in the literature. Future directions were proposed for optimizing the provision of AR for the adult CI patient population. Findings/Conclusions There is a general agreement that AR is an integral part of hearing health care for adults with CIs. While the provision of AR is feasible in different clinical practice settings, service delivery models are variable across hearing health care professionals and settings. AR may include interprofessional collaboration among surgeons, audiologists, and speech-language pathologists with varying roles based on the characteristics of a particular setting. Despite various existing barriers, the clinical practice patterns identified here provide a starting point toward a more standard approach to comprehensive AR for adults with CIs.

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Impairment Tutorial: Rating Tears of the Acetabular Labrum

Guides Newsletter ◽

10.1001/amaguidesnewsletters.2006.novdec02 ◽

2006 ◽

Vol 11 (6) ◽

pp. 4-7

Author(s):

Charles N. Brooks ◽

Richard E. Strain ◽

James B. Talmage

Keyword(s):

Magnetic Resonance ◽

Hip Arthroscopy ◽

Age Groups ◽

Limited Range ◽

Labral Repair ◽

X Rays ◽

Joint Stability ◽

Acetabular Labrum ◽

Complete Excision ◽

Limited Range Of Motion

Abstract The primary function of the acetabular labrum, like that of the glenoid, is to deepen the socket and improve joint stability. Tears of the acetabular labrum are common in older adults but occur in all age groups and with equal frequency in males and females. The AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Fifth Edition, is silent about rating tears, partial or complete excision, or repair of the acetabular labrum. Provocative tests to detect acetabular labrum tears involve hip flexion and rotation; all rely on production of pain in the groin (typically), clicking, and/or locking with passive or active hip motions. Diagnostic tests or procedures rely on x-rays, conventional arthrography, computerized tomography, magnetic resonance imaging (MRI), magnetic resonance arthrography (MRA), and hip arthroscopy. Hip arthroscopy is the gold standard for diagnosis but is the most invasive and most likely to result in complications, and MRA is about three times more sensitive and accurate in detecting acetabular labral tears than MRI alone. Surgical treatment for acetabular labrum tears usually consists of arthroscopic debridement; results tend to be better in younger patients. In general, an acetabular labral tear, partial labrectomy, or labral repair warrants a rating of 2% lower extremity impairment. Evaluators should avoid double dipping (eg, using both a Diagnosis-related estimates and limited range-of-motion tests).

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Indirect Assessment of Attitudes with Response-Time-Based Measures

Zeitschrift für Sozialpsychologie ◽

10.1024/0044-3514.37.3.131 ◽

2006 ◽

Vol 37 (3) ◽

pp. 131-139 ◽

Cited By ~ 15

Author(s):

Juliane Degner ◽

Dirk Wentura ◽

Klaus Rothermund

Keyword(s):

Social Cognitive ◽

Incremental Validity ◽

Self Report ◽

Small Scale ◽

Implicit Measures ◽

Scale Theory ◽

Starting Point ◽

Self Reports ◽

Predicting Behavior ◽

Social Cognitive Theories

Abstract: We review research on response-latency based (“implicit”) measures of attitudes by examining what hopes and intentions researchers have associated with their usage. We identified the hopes of (1) gaining better measures of interindividual differences in attitudes as compared to self-report measures (quality hope); (2) better predicting behavior, or predicting other behaviors, as compared to self-reports (incremental validity hope); (3) linking social-cognitive theories more adequately to empirical research (theory-link hope). We argue that the third hope should be the starting point for using these measures. Any attempt to improve these measures should include the search for a small-scale theory that adequately explains the basic effects found with such a measure. To date, small-scale theories for different measures are not equally well developed.

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The Solidarity of Distance1

Zeitschrift für Sozialpsychologie ◽

10.1024/0044-3514.36.3.103 ◽

2005 ◽

Vol 36 (3) ◽

pp. 103-115 ◽

Cited By ~ 3

Author(s):

Robert A. Wicklund

Keyword(s):

Physical Contact ◽

Emotional Distance ◽

Starting Point ◽

Shared Emotions ◽

Common Goals ◽

Full Interaction ◽

The Individual ◽

Social Incompetence

Abstract: Solidarity in the classic sense pertains to a cohesion among humans that entails physical contact, shared emotions, and common goals or projects. Characteristic cases are to be found among families, close friends, or co-workers. The present paper, in contrast, treats a phenomenon of the solidarity of distance, a solidarity based in fear of certain others and in incompetence to interact with them. The starting point for this analysis is the person who is motivated to interact with others who are unfamiliar or fear-provoking. Given that the fear and momentary social incompetence do not allow a full interaction to ensue, the individual will move toward solidarity with those others on a symbolic level. In this manner the motivation to approach the others is acted upon while physical and emotional distance is retained.

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