33 research outputs found
A comparison of leg length and femoral offset discrepancies in hip resurfacing, large head metal-on- metal and conventional total hip replacement: a case series
<p>Abstract</p> <p>Background</p> <p>A discrepancy in leg length and femoral offset restoration is the leading cause of patient dissatisfaction in hip replacement surgery and has profound implications on patient quality of life. The aim of this study is to compare biomechanical hip reconstruction in hip resurfacing, large-diameter femoral head hip arthroplasty and conventional total hip replacement.</p> <p>Method</p> <p>Sixty patient's post-operative radiographs were reviewed; 20 patients had a hip resurfacing (HR), 20 patients had a Large Head Metal-on-metal (LHM) hip replacement and 20 patients had a conventional small head Total Hip Replacement (THR). The leg length and femoral offset of the operated and unoperated hips were measured and compared.</p> <p>Results</p> <p>Hip resurfacing accurately restored hip biomechanics with no statistical difference in leg length (<it>P </it>= 0.07) or femoral offset (<it>P </it>= 0.95) between the operated and non-operative hips. Overall HR was superior for reducing femoral offset discrepancies where it had the smallest bilateral difference (-0.2%, <it>P </it>= 0.9). The traditional total hip replacement was least effective at restoring the hip anatomy.</p> <p>Conclusion</p> <p>The use of a larger-diameter femoral head in hip resurfacing does not fully account for the superior biomechanical restoration, as LHM did not restore femoral offset as accurately. We conclude that restoration of normal hip biomechanics is best achieved with hip resurfacing.</p
Stent redilation in canine models of congenital heart disease: Pulmonary artery stenosis and coarctation of the aorta
In a canine puppy model, pulmonary artery stenosis was created by banding the left pulmonary artery to 30–40% of its original diameter. Animals underwent right heart catheterization and angiography 1–2 mo later, and Palmaz P308 stents were implanted. Stent redilation was performed 3–5 mo later. One mo postredilation, the animals were restudied and sacrificed. Coarctations of the aorta were created by transverse aortic incision and longitudinal repair. P308 stent implantation was performed 2–3 mo later. Stent redilation was performed after 6–10 mo, and the animals were restudied and sacrificed 1–2 mo later. Stent implantation was performed in 6 puppies with pulmonary artery stenosis, as 2 animals developed postoperative pulmonary arterial hypoplasia, precluding stenting. The stenosis diameter increased from 4.8 ± 0.5 mm to 7.4 ± 0.6 mm (mean ± SE) following stenting ( P = 0.005), and increased further to 9.2 ± 0.7 mm following redilation ( P < 0.001). There were no significant vessel tears or ruptures. Coarctation stenting was performed in 8 animals. The coarctation was dilated from 5.8 ± 0.9 mm to 9.8 ± 0.6 mm ( P < 0.001), and to 13.5 ± 0.5 mm at redilation ( P = 0.002). Redilation could not be performed in 1 animal. Aortic rupture and death occurred in 2 of 7 animals at redilation. Stent implantation and redilation in experimental pulmonary artery stenosis appears safe and effective. Though stent implantation for coarctation of the aorta appears safe, there was a 28% aortic rupture rate at stent redilation in this model. © 1996 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/38176/1/24_ftp.pd
Sleep study, respiratory mechanics, chemosensitive response and quality of life in morbidly obese patients undergoing bariatric surgery: a prospective, randomized, controlled trial
<p>Abstract</p> <p>Background</p> <p>Obesity is a major public health problem in both developed and developing countries alike and leads to a series of changes in respiratory physiology. There is a strong correlation between obesity and cardiopulmonary sleep disorders. Weight loss among such patients leads to a reduction in these alterations in respiratory physiology, but clinical treatment is not effective for a long period of time. Thus, bariatric surgery is a viable option.</p> <p>Methods/Design</p> <p>The present study involves patients with morbid obesity (BMI of 40 kg/m<sup>2 </sup>or 35 kg/m<sup>2 </sup>to 39.9 kg/m<sup>2 </sup>with comorbidities), candidates for bariatric surgery, screened at the Santa Casa de Misericórdia Hospital in the city of Sao Paulo (Brazil). The inclusion criteria are grade III morbid obesity, an indication for bariatric surgery, agreement to participate in the study and a signed term of informed consent. The exclusion criteria are BMI above 55 kg/m<sup>2</sup>, clinically significant or unstable mental health concerns, an unrealistic postoperative target weight and/or unrealistic expectations of surgical treatment. Bariatric surgery candidates who meet the inclusion criteria will be referred to Santa Casa de Misericórdia Hospital and will be reviewed again 30, 90 and 360 days following surgery. Data collection will involve patient records, personal data collection, objective assessment of HR, BP, neck circumference, chest and abdomen, collection and analysis of clinical preoperative findings, polysomnography, pulmonary function test and a questionnaire on sleepiness.</p> <p>Discussion</p> <p>This paper describes a randomised controlled trial of morbidly obese patients. Polysomnography, respiratory mechanics, chemosensitive response and quality of life will be assessed in patients undergoing or not undergoing bariatric surgery.</p> <p>Trial Registration</p> <p>The protocol for this study is registered with the Brazilian Registry of Clinical Trials - ReBEC (RBR-9k9hhv).</p
Bostonia: 1997-1998, no. 1-4
Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs
KEPLER's First Rocky Planet: Kepler-10b
NASA's Kepler Mission uses transit photometry to determine the frequency of
earth-size planets in or near the habitable zone of Sun-like stars. The mission
reached a milestone toward meeting that goal: the discovery of its first rocky
planet, Kepler-10b. Two distinct sets of transit events were detected: 1) a 152
+/- 4 ppm dimming lasting 1.811 +/- 0.024 hours with ephemeris
T[BJD]=2454964.57375+N*0.837495 days and 2) a 376 +/- 9 ppm dimming lasting
6.86 +/- 0.07 hours with ephemeris T[BJD]=2454971.6761+N*45.29485 days.
Statistical tests on the photometric and pixel flux time series established the
viability of the planet candidates triggering ground-based follow-up
observations. Forty precision Doppler measurements were used to confirm that
the short-period transit event is due to a planetary companion. The parent star
is bright enough for asteroseismic analysis. Photometry was collected at
1-minute cadence for >4 months from which we detected 19 distinct pulsation
frequencies. Modeling the frequencies resulted in precise knowledge of the
fundamental stellar properties. Kepler-10 is a relatively old (11.9 +/- 4.5
Gyr) but otherwise Sun-like Main Sequence star with Teff=5627 +/- 44 K,
Mstar=0.895 +/- 0.060 Msun, and Rstar=1.056 +/- 0.021 Rsun. Physical models
simultaneously fit to the transit light curves and the precision Doppler
measurements yielded tight constraints on the properties of Kepler-10b that
speak to its rocky composition: Mpl=4.56 +/- 1.29 Mearth, Rpl=1.416 +/- 0.036
Rearth, and density=8.8 +/- 2.9 gcc. Kepler-10b is the smallest transiting
exoplanet discovered to date.Comment: Accepted, Astrophysical Journal, November 25, 2010; Eexpected
publication date: February 20, 201
Bostonia: 1997-1998, no. 1-4
Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs