Dilation of the aortic root in children infected with human immunodeficiency virus type 1 : The Prospective P2C2 HIV Multicenter Study

BACKGROUND: Vascular lesions have become more evident in human immunodeficiency virus type 1 (HIV)-infected patients as the result of earlier diagnosis, improved treatment, and longer survival. Aortic root dilation in HIV-infected children has not previously been described. This study was undertaken to determine the prevalence of aortic root dilation in HIV-infected children and to evaluate some of the potential pathogenic mechanisms. METHODS: Aortic root measurements were incorporated into the routine echocardiographic surveillance of 280 children of HIV-infected women: an older cohort of 86 HIV-infected children and a neonatal cohort of 50 HIV-infected and 144 HIV-uninfected children. RESULTS: By repeated-measures analyses, mean aortic root measurements were significantly increased in HIV-infected children versus HIV-uninfected children (P values of ≤.04 and ≤.005 at 2 and 5 years of age, respectively, for aortic annulus diameter, sinuses of Valsalva, and sinotubular junction). Heart rate, systolic blood pressure, stroke volume, hemoglobin, and hematocrit were not significantly associated with aortic root size. Left ventricular dilation, increased serum HIV RNA levels, and lower CD4 cell count measurements were associated with aortic root dilation at baseline. CONCLUSIONS: Mild and nonprogressive aortic root dilation was seen in children with vertically transmitted HIV infection from 2 to 9 years of age. Aortic root size was not significantly associated with markers for stress-modulated growth; however, aortic root dilation was associated with left ventricular dilation, increased viral load, and lower CD4 cell count in HIV-infected children. As prolonged survival of HIV-infected patients becomes more prevalent, some patients may require long-term follow-up of aortic root size

Experimental Investigation of Effect of Environment Temperature on Freeze-Form Extrusion Fabrication

Freeze-form Extrusion Fabrication (FEF) is an additive manufacturing technique that extrudes ceramic loaded aqueous pastes layer by layer below the paste freezing temperature for component fabrication. A computer controlled 3-D gantry system has been developed for the FEF process. The system includes a temperature control subsystem that allows for fabrication of components below the paste freezing temperature. The low temperature environment allows for larger component fabrication. Comparisons in terms of layer thickness, self-sustaining ability, and system response were performed between 0⁰C and -20⁰C for alumina sample fabrications. The minimum deposition angles without use of support material have been determined for 20⁰C, 10⁰C, 0⁰C, -10⁰C and -20⁰C fabrications

Measurement of Nitinol Recovery Distance Using Pseudoelastic Intramedullary Nail in Tibiotalocalcaneal Arthrodesis

Category: Ankle Introduction/Purpose: Tibiotalocalcaneal(TTC) arthrodesis is a salvage procedure for patients with complex disease of the ankle and subtalar joints. Despite the clinical efficacy and mechanical advantage of intramedullary nails, complications, such as nonunion, are not uncommon. It may be possible to sustain compression in the face of bone resorption and implant loosening over the course of healing using a novel pseudoelastic intramedullary nail. Methods: We identified 15 patients (age+54.7+/-20.0 years) who had undergone a tibiotalocalcaneal arthrodesis using a pseudoelastic intramedullary nai. Serial radiographs were used to determine the amount and rate of Nitinol element migration over time. Results: Three months after surgery, there was at least 2.38mm of Nitinol element migration proximally with mean of 5.58mm(range: 2.38 to 8.11mm). Average follow up time was 195 days (range: 89 to 490 days). Conclusion: The Nitinol element recovers distance when stretched intra-operatively and maintains moderate compression in response to bone resorption. Further studies are needed to assess if this increased compression lends itself to higher fusion rates than traditional IMN’s

Sparing the Naviculocuneiform Joint during Medial Column Stabilization for Rigid Flatfoot Deformity

Category: Midfoot/Forefoot Introduction/Purpose: Combined arthrodesis of the talonavicular (TN) and 1st tarsometatarsal (TMT) joints is a treatment option for the patient with both a rigid flatfoot and hallux valgus deformity or 1st TMT joint arthritis. In these cases, the naviculocuneiform (NC) joint is spared, as long as no evidence of joint collapse or instability is present. The purpose of this study was to assess the effect of this medial column stabilization construct on the spared NC joint over time and its ability to improve the radiographic parameters in the flatfoot deformity. Methods: Patients who underwent concomitant TN and 1st TMT joint arthrodesis, while sparing the NC joint, in the setting of a rigid flatfoot deformity, between January 2006 and December 2014, were identified. The medical records, including preoperative and postoperative radiographs were retrospectively reviewed. Outcomes included radiographic correction gained by surgery (AP and lateral talo-first metatarsal angles), union rate, complications, and need for subsequent surgery. Specific radiographic attention was paid to development of subsequent collapse and/or arthritis at the NC joint at the time of final follow-up. Results: 21 consecutive combined TN and 1st TMT joint arthrodeses were performed. Average age at time of surgery was 61 (range, 23-82) years. 17 patients had a mean follow-up of 35 (range, 12-88) months. Union was achieved at both arthrodesis sites in 16/17 patients (94.1%). One patient (5.9%) had a nonunion at the TN joint, requiring revision arthrodesis. The mean lateral talo- first metatarsal angle correction was 24.5 (range, 12-36) degrees. The mean AP talo-first metatarsal angle correction was 11.6 (range, 0-33) degrees. One patient (5.9%) developed NC joint collapse and underwent subsequent arthrodesis at that level. There was radiographic evidence of NC joint arthritis to varying degrees in all cases by the time of final follow-up, however, none were symptomatic to warrant arthrodesis. Conclusion: Simultaneous arthrodesis of the TN and 1st TMT joints, while sparing the NC joint, is a reliable treatment in the carefully selected patient who presents with both a rigid flatfoot and hallux valgus deformity or 1st TMT joint arthritis. Good results in terms of union rate and radiographic correction, as well as a low complication rate were found in this study. Subsequent joint collapse and symptomatic arthritis at the spared NC joint was rare. Longer term follow-up and inclusion of functional outcomes are warranted in future studies on this topic

Osteochondral Lesions of the Talus

Osteochondral lesions of the talus (OLTs) are a difficult pathologic entity to treat. They require a strong plan. Lesion size, location, chronicity, and characteristics such as displacement and the presence of subchondral cysts help dictate the appropriate treatment required to achieve a satisfactory result. In general, operative treatment is reserved for patients with displaced OLTs or for patients who have failed nonoperative treatment for 3 to 6 months. Operative treatments can be broken down into cartilage repair, replacement, and regenerative strategies. There are many promising treatment options, and research is needed to elucidate which are superior to minimize the morbidity from OLTs

Prevalence of Congenital Cardiovascular Malformations in Children of Human Immunodeficiency Virus-Infected Women: The Prospective P2C2 HIV Multicenter Study

AbstractObjectives. The purpose of the study was to assess the effects of maternal HIV-1 (human immunodeficiency virus) infection and vertically transmitted HIV-1 infection on the prevalence of congenital cardiovascular malformations in children.Background. In the United States, an estimated 7000 children are born to HIV-infected women annually. Previous limited reports have suggested an increase in the prevalence of congenital cardiovascular malformations in vertically transmitted HIV-infected children.Methods. In a prospective longitudinal multicenter study, diagnostic echocardiograms were performed at 4–6-month intervals on two cohorts of children exposed to maternal HIV-1 infection: 1) a Neonatal Cohort of 90 HIV-infected, 449 HIV-uninfected and 19 HIV-indeterminate children; and 2) an Older HIV-Infected Cohort of 201 children with vertically transmitted HIV-1 infection recruited after 28 days of age.Results. In the Neonatal Cohort, 36 lesions were seen in 36 patients, yielding an overall congenital cardiovascular malformation prevalence of 6.5% (36/558), with a 8.9% (8/90) prevalence in HIV-infected children and a 5.6% (25/449) prevalence in HIV-uninfected children. Two children (2/558, 0.4%) had cyanotic lesions. In the Older HIV-Infected Cohort, there was a congenital cardiovascular malformation prevalence of 7.5% (15/201). The distribution of lesions did not differ significantly between the groups.Conclusions. There was no statistically significant difference in congenital cardiovascular malformation prevalence in HIV-infected versus HIV-uninfected children born to HIV-infected women. With the use of early screening echocardiography, rates of congenital cardiovascular malformations in both the HIV-infected and HIV-uninfected children were five- to ten-fold higher than rates reported in population-based epidemiologic studies but not higher than in normal populations similarly screened. Potentially important subclinical congenital cardiovascular malformations were detected

Cardiac Dysfunction and Mortality in HIV-Infected Children

BACKGROUND: Left ventricular (LV) dysfunction is common in children infected with the human immunodeficiency virus (HIV), but its clinical importance is unclear. Our objective was to determine whether abnormalities of LV structure and function independently predict all-cause mortality in HIV-infected children. METHODS AND RESULTS: Baseline echocardiograms were obtained on 193 children with vertically transmitted HIV infection (median age, 2.1 years). Children were followed up for a median of 5 years. Cox regression was used to identify measures of LV structure and function predictive of mortality after adjustment for other important demographic and baseline clinical risk factors. The time course of cardiac variables before mortality was also examined. The 5-year cumulative survival was 64%. Mortality was higher in children who, at baseline, had depressed LV fractional shortening (FS) or contractility; increased LV dimension, thickness, mass, or wall stress; or increased heart rate or blood pressure (P≤0.02 for each). Decreased LV FS (P<0.001) and increased wall thickness (P=0.004) were also predictive of increased mortality after adjustment for CD4 count (P<0.001), clinical center (P<0.001), and encephalopathy (P<0.001). FS showed abnormalities for up to 3 years before death, whereas wall thickness identified a population at risk only 18 to 24 months before death. CONCLUSIONS: Depressed LV FS and increased wall thickness are risk factors for mortality in HIV-infected children independent of depressed CD4 cell count and neurological disease. FS may be useful as a long-term predictor and wall thickness as a short-term predictor of mortality