Search

We evaluated the usefulness of a recent measure of drinking water nitrate as a predictor of long-term average nitrate exposure calculated from historic data. Exposure estimates were calculated for 214 study participants who used public water supplies between 1947 and 1980 in Minnesota. Long-term average nitrate was calculated by linking residential histories to historical nitrate data. For recent exposures, we averaged nitrate measurements in 1980, or the next closest year with measurements. The Spearman correlation coefficient for the relationship between the two measures was 0.54 (95% confidence interval [CI] = 0.44-0.63). Agreement was highest among those residing 34 or more years in their town as of 1980 (r[SUBs] = 0.70; 95% CI = 0.55-0.80). These findings suggest that taking into account the study participants' duration of residence may enhance the validity of using a recent measure as an indicator of past exposures. [ABSTRACT FROM AUTHOR]

Presents several letters to the editor in reference to articles and topics discussed in previous issues. "The Attorney and the Non-Attorney Arbitrator," which discusses the engineer-arbitrator's style, published in the Fall 1997 issue; Remarks on the policy statement of the U.S. Equal Employment Opportunity Commission regarding mandatory mediation.

Background and Purpose: Caffeine is associated with a lower risk of some neurological diseases, but few prospective studies have investigated caffeine intake and risk of amyotrophic lateral sclerosis (ALS) mortality. We therefore determined associations between coffee, tea and caffeine intake, and risk of ALS mortality., Methods: We conducted pooled analyses of eight international, prospective cohort studies, including 351 565 individuals (120 688 men and 230 877 women). We assessed coffee, tea and caffeine intake using validated food-frequency questionnaires administered at baseline. We used Cox regression to estimate study- and sex-specific risk ratios and 95% confidence intervals (CI) for ALS mortality, which were then pooled using a random-effects model. We conducted analyses using cohort-specific tertiles, absolute common cut-points and continuous measures of all exposures., Results: During follow-up, 545 ALS deaths were documented. We did not observe statistically significant associations between coffee, tea or caffeine intake and risk of ALS mortality. The pooled multivariable risk ratio (MVRR) for ≥3 cups per day vs. >0 to <1 cup per day was 1.04 (95% CI, 0.74-1.47) for coffee and 1.17 (95% CI, 0.77-1.79) for tea. The pooled MVRR comparing the highest with the lowest tertile of caffeine intake (mg/day) was 0.99 (95% CI, 0.80-1.23). No statistically significant results were observed when exposures were modeled as tertiles or continuously., Conclusions: Our results do not support associations between coffee, tea or total caffeine intake and risk of ALS mortality., (© 2018 EAN.)

Recent studies in the USA and elsewhere have identified a possible association between Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS) and melanoma. However, empirical evidence is very limited. We conducted a study of all people diagnosed as having melanoma in Australia since 1982 (n = 127,037). The subjects, excluding those who had died within 12 months of diagnosis, were followed until 31 December 2001. We then compared their mortality risk of ALS and PD to that of the general population. There were a total of 53 ALS deaths and 129 deaths due to PD. Although the absolute risk is small, the melanoma cohort had a risk of death due to ALS 70% higher (standardised mortality ratio = 169.4, 95% CI = 127-221) than the general population, and nearly a 3-fold increased risk of dying from PD (standardised mortality ratio = 266.3, 95% CI = 222-317). These increased risks continued for long-term survivors, arguing against a surveillance effect (particularly for ALS). The consistency of these results in 2 separate populations (Australia and USA) strengthens the evidence for an association between melanoma and each of the 2 neurodegenerative diseases.

Objectives: This study explored the risk of childhood acute lymphoblastic leukemia (ALL) associated with participation by household members in hobbies or other home projects involving organic solvents., Methods: Participants in this case-control study were 640 subjects with ALL and 640 matched controls., Results: Childhood ALL was associated with frequent (> 4 times/month) exposure to model building (odds ratio [OR] = 1.9; 95% confidence interval [95% CI] = 0.7, 5.8) and artwork using solvents (OR = 4.1; 95% CI = 1.1, 15.1). We also found elevated risk (OR = 1.7; 95% CI = 1.1, 2.7) among children whose mothers lived in homes painted extensively (> 4 rooms) in the year before the children's birth., Conclusions: In this exploratory study, substantial participation by household members in some common household activities that involve organic solvents was associated with elevated risks of childhood ALL.

Relatively few studies investigating the vascular patterns of the carpus have been performed. Technical difficulties in identifying small vessels in three dimensions and in determining their location within the thick ligaments about the wrist have led to conflicting anatomic reports. Studies on cadavers in which improved techniques with arterial injection, chemical debridement, and decalcification were used allowed the arterial anatomy of the carpus to be delineated more accurately. The current authors review these arterial patterns, with attention given to the extraosseous and intraosseous vascularities.

Nitrate in drinking water has been implicated as a possible risk factor for non-Hodgkin's lymphoma. The authors examined the association between non-Hodgkin's lymphoma and waterborne nitrate through a population-based case-control study of white men in Minnesota. The authors, by linking residential histories with community water records, estimated average long-term exposure to nitrate in drinking water from 1947 to 1975 for 73 cases diagnosed between 1980 and 1982 and for 147 controls who used community water supplies. No association was found between nitrate levels in community water supplies and non-Hodgkin's lymphoma within the range of study exposures (median of highest exposure category = 2.4 mg nitrate/l [range = 0.1-7.2 mg/l]). The findings provide some safety assurance for those who use water systems that have nitrate levels that are less than 2.4 mg/l.

It has been hypothesized that instability of the thumb trapeziometacarpal joint is a major factor in the etiology of degenerative disease. Theoretically, surgically stabilized joints should be subject to less shear force and, hence, will be less likely to develop degenerative changes. The long-term results of volar ligament reconstruction were assessed in 19 patients (24 thumbs). The average age at surgery was 33 years (range, 18-55 years). Twenty-three thumbs were radiographic stage I; a preoperative x-ray was not available in 1. The follow-up period averaged 15 years (range, 10-23 years). At the final follow-up visit 15 thumbs were stage I, 7 were stage II, and 2 were stage III. Fifteen patients were at least 90% satisfied with the results of the surgery. Only 8% of thumbs advanced to radiographic arthritic disease, which compares favorably with the 17% to 33% reported incidence of stage III/IV basal joint arthritis in the general population., (Copyright 2000 by the American Society for Surgery of the Hand.)

In the alpha-Tocopherol, beta-Carotene Cancer Prevention (ATBC) study, a large randomized placebo-controlled trial designed to test the cancer prevention effects of alpha-tocopherol (50 mg/day) and beta-carotene (20 mg/day), participants receiving supplemental beta-carotene had significantly higher rates of lung cancer than those not receiving beta-carotene. It has been hypothesized that the supplemental beta-carotene may have interfered with the synthesis of vitamin D and that the resulting lower concentrations of vitamin D contributed to the elevated cancer incidence. We evaluated whether supplementation with beta-carotene altered the serum concentrations of either 25-hydroxyvitamin D or 1,25-dihydroxyvitamin D in the ATBC Study, by comparing on-study changes between baseline and follow-up serum samples among 20 randomly selected matched pairs of subjects from the beta-carotene and placebo groups. In a matched-pair analysis, the difference between the changes in both 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D in the beta-carotene supplement and placebo groups were small and statistically nonsignificant. These results provide no evidence that beta-carotene supplementation interferes with the endogenous production of 25-hydroxyvitamin D or 1,25-dihydroxyvitamin D and suggest that it is unlikely that an interaction between supplemental beta-carotene and vitamin D metabolites contributed to the modest increase in lung cancer incidence observed in the ATBC Study.

For many years, Maryland has ranked among the top states in cancer mortality. This study analyzed mortality data from the National Center for Health Statistics (CDC-Wonder) to help explain Maryland's cancer rate and rank. Age-adjusted rates are based on deaths per 100,000 population from 1991 through 1995. Rates and ranks overall, and stratified by age, are calculated for total cancer mortality, as well as for four major sites: lung, breast, prostate, and colorectal. Because states differ in their racial/gender mix, race/gender rates among states are also compared. Although Maryland ranks seventh in overall cancer mortality, its rates and rank by race and gender subpopulation are less high. For those under 75, white men ranked 26th, black men ranked 20th, and black and white women ranked 12th and 10th, respectively. Maryland's overall rank, as with any state, is a function of the rates of its racial and gender subpopulations and the relative size of these groups in the state. Many of the disparities between Maryland's overall high cancer rank and its lower rank by subpopulation also characterize the major cancer sites. Although a stratified presentation of cancer rates and ranks may be more favorable to Maryland, it should not be used to downplay the attention cancer mortality in Maryland deserves.

Computed tomography scans have supplanted conventional tomography for many applications and often are considered the imaging study of choice for assessing intraarticular distal radial fractures. Concern about cost containment in healthcare delivery prompts the question of whether the two studies provide comparable information and at what cost. Common intraarticular distal radial fractures were created in 12 lightly embalmed cadaveric specimens. The fractures were fixed with radiolucent Kirschner wires. Articular step off was measured with a caliper. Plain radiographs, computed tomography scans, and trispiral tomograms were obtained of each specimen. Maximal step off was measured blindly by two musculoskeletal radiologists and four hand surgeons. The radiographic measurements were compared with the actual step off and expressed as a positive or negative deviation from the actual value. There was no statistically significant difference between computed tomography scans and tomograms in predicting step off. In addition, the difference between actual and radiographic measurements was insignificant in tomogram readings and different in one of the computed tomography measurements. In the authors' institution, a tomogram costs $200, and a computed tomography scan costs $562. Trispiral tomography is more accurate and cost effective than computed tomography, and thus when available should be considered the imaging modality of choice for assessing articular step off in distal radius fractures.

Ankle arthroscopy has been increasingly applied to the diagnostic and therapeutic treatment of ankle disorders. Owing to the complex cutaneous anatomy of the ankle, neurological injuries are a potential complication of this procedure. All reports of neurological complications resulting from ankle arthroscopy have attributed them to use of a distractor pin or to portal placement. Several authors have noted the possibility of damage to the deep peroneal nerve from the use of motorized arthroscopic tools within the anterior ankle joint capsule. We present what we believe to be the first reported case of complete division of the posterior tibial nerve resulting from an apparently overaggressive intra-articular manipulation during ankle arthroscopy performed for loose body removal.

One hundred skeletally mature healthy volunteers underwent standardized bilateral posteroanterior radiographs in unloaded (static) and loaded (dynamic) conditions to determine the symmetry of ulnar variance. The mean age was 32 +/- 9 years (range, 19-61 years), with 58 women and 42 men. Ulnar variance was measured to the closest 0.5 mm using the method of perpendiculars. Three separate measurements were made of each radiograph in a blinded fashion by the same investigator. An intraobserver standard deviation of 0.21 was used to calculate a 95% tolerance interval of 0.7 mm (rounded up to 1 mm) as a measure of significance. The average static ulnar variance was -0.13 +/- 1.5 mm on the left and -0.29 +/- 1.6 mm on the right. The average dynamic ulnar variance was 0.93 +/- 1.5 mm on the left and 0.82 +/- 1.5 mm on the right. When compared individually, there was a greater than or equal to 1 mm side to side difference in 37% of volunteers under static and 38% under dynamic conditions. There were no significant correlations between ulnar variance measurements and patient age, gender, race, or handedness. Use of the normal wrist radiograph as a baseline for static radial length measurements is valid in only 63% of cases.

We present a case of progressive heterotopic ossification (HO) after cementless total knee arthroplasty causing painful stiffness that was treated with surgical excision. The patient had few risk factors associated with HO, including minimal anterior notching and dissection of the distal femoral cortex. The patient did undergo manipulation; however, this occurred after the diagnosis of HO was made. This report documents a rare case of HO following total knee arthroplasty that required surgical excision.