Whole blood lead levels are associated with radiographic and symptomatic knee osteoarthritis: a cross-sectional analysis in the Johnston County Osteoarthritis Project

Abstract Introduction Lead (Pb) is known to affect bone, and recent evidence suggests that it has effects on cartilage as well. As osteoarthritis (OA) is a highly prevalent disease affecting bone and cartilage, we undertook the present analysis to determine whether whole blood Pb levels are associated with radiographic and symptomatic OA (rOA and sxOA, respectively) of the knee. Methods The analysis was conducted using cross-sectional data from the Johnston County Osteoarthritis Project, a rural, population-based study, including whole blood Pb levels, bilateral posteroanterior weight-bearing knee radiography and knee symptom data. rOA assessment included joint-based presence (Kellgren-Lawrence (K-L) grade 2 or higher) and severity (none, K-L grade 0 or 1; mild, K-L grade 2; moderate or severe, K-L grade 3 or 4), as well as person-based laterality (unilateral or bilateral). SxOA was deemed present (joint-based) in a knee on the basis of K-L grade 2 or higher with symptoms, with symptoms rated based on severity (0, rOA without symptoms; 1, rOA with mild symptoms; 2, rOA with moderate or severe symptoms) and in person-based analyses was either unilateral or bilateral. Generalized logit or proportional odds regression models were used to examine associations between the knee OA status variables and natural log-transformed blood Pb (ln Pb), continuously and in quartiles, controlling for age, race, sex, body mass index (BMI), smoking and alcohol drinking. Results Those individuals with whole blood Pb data (N = 1,669) had a mean (±SD) age of 65.4 (±11.0) years and a mean BMI of 31.2 (±7.1) kg/m2, including 66.6% women and 35.4% African-Americans, with a median blood Pb level of 1.8 μg/dl (range, 0.3 to 42.0 μg/dl). In joint-based analyses, for every 1-U increase in ln Pb, the odds of prevalent knee rOA were 20% higher (aOR, 1.20; 95% CI, 1.01 to 1.44), while the odds of more severe rOA were 26% higher (aOR, 1.26; 95% CI, 1.05 to 1.50, under proportional odds). In person-based analyses, the odds of bilateral rOA were 32% higher for each 1-U increase in ln Pb (aOR, 1.32; 95% CI, 1.03 to 1.70). Similarly for knee sxOA, for each 1-U increase in ln Pb, the odds of having sxOA were 16% higher, the odds of having more severe symptoms were 17% higher and the odds of having bilateral knee symptoms were 25% higher. Similar findings were obtained with regard to ln Pb in quartiles. Conclusions Increases in the prevalence and severity measures for both radiographically and symptomatically confirmed knee OA (although statistically significant only for rOA) were observed with increasing levels of blood Pb, suggesting that Pb may be a potentially modifiable environmental risk factor for OA

The effects of lateral meniscal allograft transplantation techniques on tibio-femoral contact pressures.

Accepted versio

The long-term results of meniscus transplantation for articular cartilage defects in the knee joint

Purpose: The purpose of this study was to examine the long-term clinical results of meniscus transplantation for articular cartilage defects in the knee joint. Type of study: Case series. Method: From October 1990 to June 1995, 8 cases underwent allogenic or autogenic meniscus transplantations for articular cartilage defects, and 7 cases were available for follow-up evaluations. The age at surgery ranged from 14 to 42 years old (average 22.5). In one case, a transplantation of tissue-engineered cartilage was performed due to pain 5 years after surgery. The other 6 cases were followed up for 8 to 13 years (average 10.1). The size of the cartilage defect ranged from 1.0 cm2 to 6.3 cm2 (average 2.8cm2). Patients were evaluated with the Lysholm score and MR images. We also performed arthroscopic examinations in 3 cases at the final evaluation. Results: The Lysholm scores ranged from 76 points to 100 points. In MR images, the congruities between the grafted lesions and normal cartilage were evaluated as smooth surfaces in 4, slightly irregular surface in 1, irregular surface in 1, and one had disappeared. In arthroscopic findings at 11 years after surgery, the grafted meniscus could not be found in one knee that had severe osteoarthritis changes, and in the other knee the lesion of the transplanted meniscus resembled a flap tear. In another case, the grafted meniscus and the surrounding cartilage displayed irregular surfaces during transplantation of tissue-engineered cartilage. In histological findings, at 11 years after surgery a small lesion in the grafted area was not hyaline cartilage but fibrocartilage. Conclusions: This study leads us to the conclusion that meniscus transplantation for articular cartilage damage is not compared to ACI although two cases showed good clinical results for a short term but the tissue was remained fibrocartilage tissues for long term.. Level of Evidence: Level 4, case series