Outcomes of Modular Dual Mobility Acetabular Components in Revision Total Hip Arthroplasty

BACKGROUND

There is a high rate of dislocation after revision total hip arthroplasty. This study evaluated the outcomes of 1 modular dual mobility component in revision total hip arthroplasty in patients at high risk of dislocation.

METHODS

We reviewed 64 revisions performed in 27 (42%) patients for recurrent dislocation, 16 (25%) for adverse local tissue reaction, 11 (17%) for reimplantation infection, and 10 (16%) for aseptic loosening, malposition, or fracture. Complications, reoperations, and survivorship were evaluated.

RESULTS

Three-year survival was 98% with failure defined as aseptic loosening and 91% with failure as cup removal for any reason. With mean follow-up time of 38 months, there were 14 complications, including 2 dislocations treated with closed reduction, 9 infections, and 12 reoperations. All complications occurred in patients revised for instability, adverse local tissue reaction, or infection.

CONCLUSION

The early results of this component are promising, with good overall survival and low rate of dislocation.

Intravenous Gadoxetate Disodium Administration Reduces Breath-holding Capacity in the Hepatic Arterial Phase: A Multi-Center Randomized Placebo-controlled Trial

Purpose To determine, in a multicenter double-blinded placebo-controlled trial, whether maximal hepatic arterial phase breath-holding duration is affected by gadoxetate disodium administration. Materials and Methods Institutional review board approval was obtained for this prospective multi-institutional HIPAA-compliant study; written informed consent was obtained from all subjects. At three sites, a total of 44 volunteers underwent a magnetic resonance (MR) imaging examination in which images were acquired before and dynamically after bolus injection of gadoxetate disodium, normal saline, and gadoterate meglumine, administered in random order in a single session. The technologist and volunteer were blinded to the agent. Arterial phase breath-holding duration was timed after each injection, and volunteers reported subjective symptoms. Heart rate (HR) and oxygen saturation were monitored. Images were independently analyzed for motion artifacts by three radiologists. Arterial phase breath-holding duration and motion artifacts after each agent were compared by using the Mann-Whitney U test and the McNemar test. Factors affecting the above outcomes were assessed by using a univariate, multivariable model. Results Arterial phase breath holds were shorter after gadoxetate disodium (mean, 32 seconds ± 19) than after saline (mean, 40 seconds ± 17; P < .001) or gadoterate meglumine (43 seconds ± 21, P < .001) administration. In 80% (35 of 44) of subjects, arterial phase breath holds were shorter after gadoxetate disodium than after both saline and gadoterate meglumine. Three (7%) of 44 volunteers had severe arterial phase motion artifacts after gadoxetate disodium administration, one (2%; P = .62) had them after gadoterate meglumine administration, and none (P = .25) had them after saline administration. HR and oxygen saturation changes were not significantly associated with contrast agent. Conclusion Maximal hepatic arterial phase breath-holding duration is reduced after gadoxetate disodium administration in healthy volunteers, and reduced breath-holding duration is associated with motion artifacts. ^© RSNA, 2016.

A first step toward understanding best practices in leadership training in undergraduate medical education: a systematic review

PURPOSE

To characterize leadership curricula in undergraduate medical education as a first step toward understanding best practices in leadership education.

METHOD

The authors systematically searched the PubMed, Education Resources Information Center, Academic Search Complete, and Education Full Text databases for peer-reviewed English-language articles published 1980-2014 describing curricula with interventions to teach medical students leadership skills. They characterized educational settings, curricular format, and learner and instructor types. They assessed effectiveness and quality of evidence using five-point scales adapted from Kirkpatrick's four-level training evaluation model (scale: 0-4) and a Best Evidence Medical Education guide (scale: 1-5), respectively. They classified leadership skills taught into the five Medical Leadership Competency Framework (MLCF) domains.

RESULTS

Twenty articles describing 24 curricula met inclusion criteria. The majority of curricula (17; 71%) were longitudinal, delivered over periods of one semester to four years. The most common setting was the classroom (12; 50%). Curricula were frequently provided to both preclinical and clinical students (11; 46%); many (9; 28%) employed clinical faculty as instructors. The majority (19; 79%) addressed at least three MLCF domains; most common were working with others (21; 88%) and managing services (18; 75%). The median effectiveness score was 1.5, and the median quality of evidence score was 2.

CONCLUSIONS

Most studies did not demonstrate changes in student behavior or quantifiable results. Aligning leadership curricula with competency models, such as the MLCF, would create opportunities to standardize evaluation of outcomes, leading to better measurement of student competency and a better understanding of best practices.