Quantifying osteosynthesis plate prominence - mathematical definitions and case study on a clavicle plate.

Hardware prominence remains a clinical challenge in focus for implant design in subcutaneous plate applications. Existing evaluation of hardware prominence relies on plate-to-bone distance at a single point or on average. A reproducible measure for plate prominence remains undefined. This study mathematically defines the plate prominence linked to the cross-sectional area change due to the plate presence on the bone. Two anatomical plate designs were fitted to 100 clavicles, and afterwards plate prominence parameters were evaluated and compared. This methodology enables the quantification of hardware prominence for different plate designs to inform the development of implants targeting low prominence.

The variance of clavicular surface morphology is predictable: an analysis of dependent and independent metadata variables.

BACKGROUND: The anatomy of the clavicle is specific and varied in reference to its topography and shape. These anatomic characteristics play an important role in the open treatment of clavicle fractures. The complex and variable topography creates challenges for implant placement, contouring, and position. Hardware prominence and irritation does influence the decision for secondary surgical intervention. METHODS: Computerized tomographic scans of 350 adult clavicles with the corresponding patients' metadata were acquired and digitized. Morphologic parameters determining the shape of the clavicle were defined and computed for each digitized bone. The extracted morphologic parameters were correlated with patient metadata to analyze the relationship between morphologic variability and patient characteristics. RESULTS: The morphologic parameters defining the shape, that is, the radius of the medial and lateral curves, the apparent clavicle height and width, and the clavicle bow position, correlate with the clavicle length. The clavicle length correlates with the patients' height. Gender differences in shape and form were dependent and related to individual height distribution and clavicle length. Asian populations showed a similarly predictable, but shifted, correlation between shape and clavicle length. CONCLUSION: This anatomic analysis shows that the clavicle shape can be predicted through the clavicle length and patients' stature. Smaller patients have shorter and more curved clavicles, whereas taller patients have longer and less curved clavicles. This correlation will aid surgeons in fracture reduction, implant curvature selection, and in optimal adaptation of clavicle implants, and represents the basis for anatomically accurate solutions for clavicle osteosynthesis.

Childhood infectious diseases and risk of non-Hodgkin's lymphoma according to the WHO classification: A reanalysis of the Italian multicenter case-control study.

Since 1960, incidence of non-Hodgkin's lymphoma (NHL) has been increasing in most industrialized countries, but causes of this trend remain unclear. A role of the decreased exposure to infectious agents during childhood has been proposed. Our study evaluates the association between common childhood infectious diseases and the risk of NHL and its major subtypes by a reanalysis of the Italian multicenter case-control study. After exclusion of next-of-kin interviews, 1,193 cases, diagnosed between 1990 and 1993, and 1,708 population-based controls were included in the analyses. OR estimates were obtained by logistic regression, adjusting for gender, age, residence area, education, smoking habit and exposure to radiations, pesticides and aromatic hydrocarbons. Among B-cell lymphomas (n = 1,102) an inverse association was observed for rubella (OR = 0.80, 95% CI: 0.65-0.99), pertussis (OR = 0.74, 95% CI: 0.62-0.88) and any infection (OR = 0.75, 95% CI: 0.61-0.93). A negative trend by number of infections was observed, which was more evident among mature B-cell lymphoma (OR = 0.66 for three infections or more, 95% CI: 0.48-0.90). Our results indicate a potential protective role of common childhood infections in the etiology of B-cell NHL.

Alcohol consumption and risk of leukemia: A multicenter case-control study.

A population-based case-control study of 649 leukemia cases and 1771 controls carried out in 11 Italian areas, offered the opportunity to evaluate the relationship between alcohol consumption and leukemia risk. For all leukemias, acute lymphocytic leukemia (ALL), acute myeloid leukemia (AML), and chronic lymphocytic leukemia (CLL), we found a non-significantly inverse association for moderate levels of total alcohol and wine intake, but increased risks at high levels, with, in most cases, significant trend effects (odd ratios (OR) for all leukemias in the lowest quartile of total alcohol consumption [0.1-9.0 g/day of ethanol] versus never-drinker = 0.73; 95% confidence intervals (95% CI) = 0.51-1.03; OR in the highest quartile [> 31.7 g/day] = 1.15; 95% CI = 0.82-1.63; p of the linear trend test = 0.007). For chronic myeloid leukemia (CML), we found a non-significantly positive association for all levels of total alcohol and wine intake, and a significant positive linear trend effect (p = 0.03) for wine intake (OR for 0.1-9.0 g/day of ethanol intake from wine = 1.34; 95% CI = 0.61-2.94; OR in the highest quartile of wine intake [> 27.7 g/day] = 2.13; 95% CI = 1.01-4.50). No consistent dose-response was detected analysing duration of alcohol consumption for any leukemia subtypes. In conclusion, even though our study did not show a clear association between alcohol intake and leukemia risk, some of the patterns of the risk estimates (a possible J-shaped dose-response curve between alcohol intake and ALL, AML, and CLL risks, and the positive association between alcohol and CML), may be suggestive.

Personal use of hair dyes and hematolymphopoietic malignancies.

In the context of a population-based case-control study in Italy, the authors investigated the possible association between the personal use of hair dyes and non-Hodgkin's lymphoma (NHL), leukemia, multiple myeloma, and Hodgkin's disease. They collected all incident cases of hematolymphopoietic malignancies; the control group was formed with a random sample of the general population. Overall, the authors interviewed 2,737 research subjects and 1,779 control subjects. Among women, the authors found no association between ever using hair dyes and the risk of hematolymphopoietic malignancies. However, for permanent hair dyes, the authors observed a slightly increased risk of lymphocytic leukemia (odds ratio [OR] = 1.3; 95% confidence interval [CI] = 0.8-2.2) and of follicular subtypes of NHL (OR= 1.3; 95% CI = 0.8-2.0). Women who used black hair dye colors were at an increased risk of developing leukemia (OR = 1.9; 95% CI = 1.0-3.4), in particular chronic lymphocytic leukemia (OR = 3.0; 95% CI = 1.1-7.5). In spite of the lack of information on the timing and frequency of hair dye use and the imprecision of the ORs, associations were suggested between leukemia and permanent black hair dye use and follicular NHL and the use of permanent hair dyes.

Non-Hodgkin's lymphoma and type of tobacco smoke.

BACKGROUND: In recent decades, the incidence of non-Hodgkin's lymphoma (NHL) has increased in all industrialized countries. Tobacco smoke contains several recognized or putative carcinogenic compounds that differ in concentration depending on which of the two main types, blond or black, is consumed. This investigation sought to evaluate the association between NHL and type of tobacco smoked (blond, black, or mixed), focusing on the Working Formulation (WF) subgroups. METHODS: Reanalysis of Italian data from a recent multicenter population-based case-control study. The 1450 cases of NHL and 1779 healthy controls from 11 Italian areas with different demographic and productive characteristics were included in the study, corresponding to approximately 7 million residents. Odds ratios (ORs) adjusted for age, gender, residence area, educational level, and type of interview were estimated by unconditional logistic regression model. RESULTS: A statistically significant association [OR = 1.4, 95% confidence interval (CI) 1.1-1.7] was found for blond tobacco exposure and NHL risk. A dose-response relationship was limited to men younger than 52 years (chi(2) for trend = 9.95, P < 0.001). Subjects starting smoking at an early age showed a higher risk in men younger than 65 years, whereas no clear trend was evident for the other age and gender subgroups. The analysis by WF categories showed the highest risks for follicular lymphoma in blond (OR = 2.1, 95% CI 1.4-3.2) and mixed (OR = 1.8, 95% CI 1.1-3.0) tobacco smokers and for large cell within the other WF group (OR = 1.6, 95% CI 1.1-2.4) only for blond tobacco. CONCLUSIONS: Smoking blond tobacco could be a risk factor for NHL, especially follicular lymphoma.

Non-Hodgkin's lymphoma, leukemia, and exposures in agriculture: results from the Italian multicenter case-control study.

BACKGROUND: The etiology of non-Hodgkin's lymphoma (NHL) and leukemia is still largely unknown, but exposure to chemicals, in particular pesticides, has been suggested to be a risk factor. METHODS: A large population-based case-control study was conducted in Italy with the aim of investigating the associations between pesticide exposure and NHL, and solvents and leukemia. Data presented in this article refer to 1,575 interviewed cases and 1,232 controls in the nine agricultural study areas. RESULTS: Exposure to nitro-derivatives and phenylimides among fungicides, hydrocarbon derivatives and insecticide oils among insecticides, and the herbicide amides are the chemical classes observed to be associated with the pathologies under investigation. CONCLUSIONS: The results of the case-control study suggest an increased risk for NHL and leukemia, and some chemical classes of pesticides, although few are statistically significant and some are based on few exposed cases. The results also show that men and women experience both similar and different risks for the same environmental agricultural exposures. Am. J. Ind. Med. 44:627-636, 2003.