Reaming versus broaching in cemented hip arthroplasty: mechanical stability in cadaver femora

Introduction We used an experimental hip model to assess the mechanical stability of a hip prosthesis, and compared the femoral medullary canal preparation techniques of reaming and broaching.

Methods 15 pairs of cadaveric femora had a simulated replacement, the right femur with a reaming technique and the left with a broaching technique. Both femurs were radiographed to assess component positioning and cement mantle. The femurs were osteotomized 30 days after the procedure. The shear strength of the interface was studied at 4 different levels along an aluminum rod during push-out tests.

Results The overall mean value of the interface failure load was 15% lower with the reaming technique (6.5 kN for the reaming technique versus 7.7 kN for the broaching technique; p = 0.02).

Interpretation Broaching was superior to reaming for the preparation of the femoral canal, and should be used in order to increase primary stability. Further in vivo studies are required to account for factors such as intramedullary pressure, bleeding and surgical variations, which could not be accounted for in our study.     

DOES THE MANAGEMENT OF BLADDER PERFORATION DURING TRANSURETHRAL RESECTION OF SUPERFICIAL BLADDER TUMORS PREDISPOSE TO EXTRAVESICAL TUMOR RECURRENCE?

PURPOSE: We evaluated the impact of a bladder perforation during transurethral resection of superficial bladder tumor on extravesical tumor recurrence and patient prognosis. We also defined potential risk factors for extravesical recurrence prospectively giving emphasis to the management of the perforation. MATERIALS AND METHODS: The medical records of 3,410 patients were reviewed. Parameters recorded included patient age and sex, tumor stage, grade, number, size and location at the time of perforation, the type of bladder perforation (extraperitoneal vs intraperitoneal) and the way the perforation was managed (open surgical repair vs conservative treatment). Logistic regression analysis was used to identify risk factors for extravesical recurrence. Cox regression analysis was used to compare cancer specific survival. RESULTS: A total of 34 cases of bladder perforation were recorded, 4 patients were treated with open surgery and 30 treated conservatively. The 4 patients who underwent open surgery presented with extravesical recurrence after a mean followup of 7.5 months. The remaining 30 patients had no evidence of extravesical recurrence after a mean followup of 60 months (p <0.001). Of the patients with extravesical relapse 3 died of disease. The surgical management of bladder perforation was the best predictor of extravesical recurrence (p <0.001, r = 1.13), followed by an intraperitoneal localization of the perforation (p =0.0003, r = 0.67) and tumor size (p =0.01, r = 0.42). CONCLUSIONS: Surgical repair of a bladder perforation during transurethral resection of bladder tumor increases the risk of extravesical tumor cell recurrence and negatively affects patient prognosis.     

Outcomes in adults with bicuspid aortic valves

Nikolaos Tzemos, MD; Judith Therrien, MD; James Yip, MD; George Thanassoulis, MD; Sonia Tremblay, MD; Michal T. Jamorski, BSc; Gary D. Webb, MD; Samuel C. Siu, MD, SM

JAMA. 2008;300(11):1317-1325.

Context  Bicuspid aortic valve is the most common congenital cardiac anomaly in the adult population. Cardiac outcomes in a contemporary population of adults with bicuspid aortic valve have not been systematically determined.

Objective  To determine the frequency and predictors of cardiac outcomes in a large consecutive series of adults with bicuspid aortic valve.

Design, Setting, and Participants  Cohort study examining cardiac outcomes in 642 consecutive ambulatory adults (mean [SD] age, 35 [16] years; 68% male) with bicuspid aortic valve presenting to a Canadian congenital cardiac center from 1994 through 2001 and followed up for a mean (SD) period of 9 (5) years. Frequency and predictors of major cardiac events were determined by multivariate analysis. Mortality rate in the study group was compared with age- and sex-matched population estimates.

Main Outcome Measures  Mortality and cause of death were determined. Primary cardiac events were defined as the occurrence of any of the following complications: cardiac death, intervention on the aortic valve or ascending aorta, aortic dissection or aneurysm, or congestive heart failure requiring hospital admission during the follow-up period.

Results  During the follow-up period, there were 28 deaths (mean [SD], 4% [1%]). One or more primary cardiac events occurred in 161 patients (mean [SD], 25% [2%]), which included cardiac death in 17 patients (mean [SD], 3% [1%]), intervention on aortic valve or ascending aorta in 142 patients (mean [SD], 22% [2%]), aortic dissection or aneurysm in 11 patients (mean [SD], 2% [1%]), or congestive heart failure requiring hospital admission in 16 patients (mean [SD], 2% [1%]). Independent predictors of primary cardiac events were age older than 30 years (hazard ratio [HR], 3.01; 95% confidence interval [CI], 2.15-4.19; P<.001), moderate or severe aortic stenosis (HR, 5.67; 95% CI, 4.16-7.80; P<.001), and moderate or severe aortic regurgitation (HR, 2.68; 95% CI, 1.93-3.76; P<.001). The 10-year survival rate of the study group (mean [SD], 96% [1%]) was not significantly different from population estimates (mean [SD], 97% [1%]; P = .71). At last follow-up, 280 patients (mean [SD], 45% [2%]) had dilated aortic sinus and/or ascending aorta.

Conclusions  In this study population of young adults with bicuspid aortic valve, age, severity of aortic stenosis, and severity of aortic regurgitation were independently associated with primary cardiac events. Over the mean follow-up duration of 9 years, survival rates were not lower than for the general population.

     

Long-term results of thin corneas after refractive laser surgery

PURPOSE: To report the long-term refractive results of photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) in patients with thin corneas. DESIGN: A long-term, retrospective, non-randomized follow-up study. METHODS: Sixty-three patients (124 eyes) (28 males and 35 females), who had a preoperative central corneal thickness (CCT) of less than 500 microns and completed at least one year of follow-up examinations after surgery. Thirty-five patients (68 eyes) underwent PRK and 28 patients (56 eyes) underwent LASIK. RESULTS: Mean preoperative corneal pachymetry was 484.95 +/- 6.65 microm (range, 470 to 498 microm) and 482.38 +/- 10.73 microm (range, 453 to 499 microm) for LASIK and PRK, respectively. No intraoperative complications were found in both groups. None of the included eyes developed postrefractive corneal ectasia. The mean predictability for the PRK group was 0.08 diopters (D) with a standard deviation of 0.40 D (range, -1.38 to 1.00 D), and the mean predictability for the LASIK group was 0.14 D with a standard deviation of 0.55 D (range, -1.25 to 1.33 D). CONCLUSIONS: Refractive laser surgery with LASIK or PRK in patients with thin corneas (less than 500 microm) seems to be a safe and predictable technique for myopic refractive corrections.     

Endothelial cell density after photorefractive keratectomy for moderate myopia using a 213 nm solid-state laser system

PURPOSE: To evaluate whether photorefractive keratectomy (PRK) for moderate myopia using a solid-state laser with a wavelength of 213 nm alters the corneal endothelial cell density. SETTING: University refractive surgery center. METHODS: The corneal endothelium was analyzed preoperatively and 1, 6, and 12 months postoperatively using corneal confocal microscopy (modified HRT II with a Rostock Cornea Module, Heidelberg Engineering) in 60 eyes (30 patients). Patients were randomized to have myopic PRK using a 213 nm wavelength solid-state laser (study group) or a conventional 193 nm wavelength excimer laser (control group). Three endothelial images were acquired in each of 30 preoperative normal eyes to evaluate the repeatability of endothelial cell density measurements. Repeated-measures analysis of variance was used to compare the variations in endothelial cell density between the 2 lasers and the changes in endothelial cell density over time. RESULTS: There were no statistically significant differences in sex, age, corneal pachymetry, attempted correction, preoperative endothelial cell density, or postoperative refractive outcomes (uncorrected visual acuity, best spectacle-corrected visual acuity, and spherical equivalent refraction) between the 2 groups (P>.05). The coefficient of repeatability of endothelial cell density was 131 cells/mm(2). The measured endothelial cell count per 1.0 mm(2) did not significantly change up to 1 year postoperatively in either group (both P>.05). No statistically significant difference was found between the 2 groups in any postoperative interval (P>.05). CONCLUSION: Photorefractive keratectomy for moderate myopia using a 213 nm wavelength solid-state laser or a conventional 193 nm wavelength excimer laser did not significantly affect corneal endothelial density during the 1-year postoperative period.     

Type 1 and type 2 cytokine-producing CD4+ and CD8+ T cells in primary antiphospholipid syndrome

Antiphospholipid syndrome (APS) is an autoimmune condition characterized by thrombosis and/or recurrent fetal loss as well as the presence of autoantibodies against epitopes present on phospholipid-binding proteins. The role of cellular immunity in the pathogenesis of the syndrome remains unclear. We studied the cellular phenotype and the production of type 1 [interferon (IFN)-, interleukin (IL)-2] and type 2 (IL-4, IL-10) cytokines by CD4+ and CD8+ T-lymphocyte subsets in 13 patients with untreated primary APS (PAPS) and in 32 healthy controls. The production of cytokines was determined in T cells after a 5-h culture with or without mitogenic stimulation using a flow cytometric method of intracellular cytokine staining. In six of the patients these studies were repeated 6 months later. In PAPS patients we found a reduced percentage of circulating CD4+CD45RA+ and an increased percentage and absolute number of CD8+HLA-DR+ cells. A type 1 response was observed in the patients unstimulated cells, indicated by an increase in IFN--producing CD8+, IL-2-producing CD4+ T cells, and a decrease in IL-4-producing CD4+ and CD8+ T cells. Similar results were obtained in the patients at follow-up. Taken together, these results suggest a chronic in vivo stimulation of CD4+ and CD8+ T cells in PAPS patients exhibiting a type 1 polarization. Changes of cellular immunity may contribute to the pathogenesis of the clinical manifestations of the syndrome and might be proven to be useful targets for therapeutic interventions in the future.     

Aspergillus fumigatus abscesses of the thyroid with obstruction of the esophagus.

Thyroid invasion by Aspergillus spp. can occur with invasive aspergillosis, although it is rarely diagnosed antemortem. We describe a case of multiple thyroid abscesses from A. fumigatus that caused esophageal obstruction in a patient with myelodysplasia. Despite aggressive antifungal treatment, the outcome was rapidly fatal.     

Endoscopic management and long-term follow-up of Dieulafoy's lesions in the upper GI tract

BACKGROUND: The aim of this study was to retrospectively evaluate the short-and long-term effectiveness of different methods of endoscopic treatment for bleeding Dieulafoy's lesions. METHODS: Patients were allocated into 2 groups according to the hemostatic method applied: (1) injection group (epinephrine and/or ethanolamine oleate), and (2) thermal coagulation group (heat probe), either alone or combined with epinephrine injection. The combination of epinephrine and ethanolamine oleate was used in 5 patients, epinephrine alone in 3, ethanolamine oleate alone in one, heat probe and epinephrine in 8, and heat probe alone in 1 patient. RESULTS: Dieulafoy's lesions were found in 18 (1%) of 1750 patients with acute nonvariceal upper GI bleeding. Comorbid conditions were present in 5 (28%) patients. Initial hemostasis was achieved endoscopically in 13 patients (72%) and permanent hemostasis in 17 patients (94%). Bleeding recurred in 5 patients (2 with concomitant disease) in the injection group; 3 were successfully retreated by heat probe coagulation and epinephrine injection, 1 with hemoclip application and 1 by surgery. There was no recurrent bleeding in thermal treatment group. Thermal treatment was significantly superior to injection (p = 0.0029). CONCLUSIONS: Endoscopic thermal coagulation with or without epinephrine injection should be the initial treatment of choice for Dieulafoy's lesions. Mortality is lowest in patients with no significant comorbidity and an unremarkable medical history.