Joint space width of the tibiofemoral and of the patellofemoral joint in chronic knee pain with or without radiographic osteoarthritis: a 2-year follow-up

AbstractObjectives: To assess the interval change of the minimal joint space width (MJS) in radiographs of the tibiofemoral (TF) joint and of the patellofemoral (PF) joint with a 2-year follow-up in middle-aged people with longstanding knee pain with or without radiographic osteoarthritis (OA) and to study the precision of the MJS measurements.Design: In the format of a prospective study of early OA the signal knee in 55 people, 28 men and 27 women (aged 41–57 years, median 50), with chronic knee pain at inclusion was examined with a 2-year interval (median 25 months, range 21–30). The MJS of the TF joint was measured using a flexed PA view in weightbearing and the MJS of the PF joint using an axial view in standing.Results: The MJS of the TF joint decreased medially by 0.056±0.44mm (n.s.) and increased laterally by 0.080±0.51mm (n.s.) during the time of observation. In knees with an MJS medially that was less or the same as compared with the lateral compartment, the MJS decreased by 0.14±0.38mm (p=0.038) and in a subgroup of these knees, without osteophytes, the MJS decreased by 0.14±0.27mm (p=0.018). The MJS of the PF joint decreased by 0.019mm (n.s.) during the time of observation. The coefficient of variation for intra- and interobserver MJS measurements of the TF joint was 1.0 and 1.1% medially and 2.3 and 2.7% laterally, and for measurement error 6.9% medially and 4.8% laterally, respectively. The coefficient of variation for intra- and interobserver MJS measurements of the PF joint was 8.1 and 5.8% medially and 7.5 and 10.1% laterally and for the measurement error it was 8.1% medially and 8.5% laterally, respectively.Conclusions: A statistically significant reduction of the MJS was only demonstrated in the medial compartment of the TF joint in those individuals who had an MJS in this compartment which was less or the same as compared with the lateral compartment as well as in a subgroup of these knees without osteophytes. The radiographic examinations and the MJS measurements were reproducible

Transformation kinetics of alloys under non-isothermal conditions

The overall solid-to-solid phase transformation kinetics under non-isothermal conditions has been modeled by means of a differential equation method. The method requires provisions for expressions of the fraction of the transformed phase in equilibrium condition and the relaxation time for transition as functions of temperature. The thermal history is an input to the model. We have used the method to calculate the time/temperature variation of the volume fraction of the favored phase in the alpha-to-beta transition in a zirconium alloy under heating and cooling, in agreement with experimental results. We also present a formulation that accounts for both additive and non-additive phase transformation processes. Moreover, a method based on the concept of path integral, which considers all the possible paths in thermal histories to reach the final state, is suggested.Comment: 16 pages, 7 figures. To appear in Modelling Simul. Mater. Sci. En

Altered Metabolism of Growth Hormone Receptor Mutant Mice: A Combined NMR Metabonomics and Microarray Study

Growth hormone is an important regulator of post-natal growth and metabolism. We have investigated the metabolic consequences of altered growth hormone signaling in mutant mice that have truncations at position 569 and 391 of the intracellular domain of the growth hormone receptor, and thus exhibit either low (around 30% maximum) or no growth hormone-dependent STATS signaling respectively. These mutants result in altered liver metabolism, obesity and insulin resistance

Distribution of MR-detected cartilage defects of the patellofemoral joint in chronic knee pain

Objectives: The aim of the study was to detect cartilage defects and determine the center of these defects in MR imaging of the patellofemoral joint (PFJ) in middle-aged people with chronic knee pain. Design: In the format of a prospective study of early osteoarthritis (OA), this cross-sectional study of the signal knee (the most painful one at inclusion in the study in 1990) in 59 individuals, 30 women and 29 men (aged 41-58 years, mean 50 years) with chronic knee pain, with or without radiographically determined knee OA, was examined using MR imaging on a 1.0 T imager. Cartilage defects and the center of these defects in the PFJ were recorded. Results: Cartilage defects were found more often in the patella (40 knees) than in the femoral trochlea (23 knees) (P<0.001) and were unevenly distributed in the patella (P<0.001), with most cartilage defects in the mid-patella. Conclusions: Since cartilage defects occur more commonly in the mid-patella, radiographs obtained with a knee flexion of approximately 45 may be more accurate to show cartilage defects of early OA of the PFJ than views with another knee flexion. Crown Copyright (C) 2003 Published by Elsevier Science Ltd on behalf of OsteoArthritis Research Society International. All rights reserved

Comparison of clinical and neuroradiological findings in first-ever stroke. A population-based study

BACKGROUND AND PURPOSE: To determine how a recently proposed clinical stroke subclassification corresponds to specific findings on computed tomography (CT) and magnetic resonance imaging (MRI) of the brain. METHODS: Two hundred twenty-eight patients with first-ever stroke were divided into four clinical subgroups: (1) total anterior circulation syndrome: both cortical and subcortical symptoms from anterior and middle cerebral artery territory; (2) partial anterior circulation syndrome: more restricted and predominantly cortical symptoms from the same arterial territories; (3) lacunar syndrome; and (4) posterior circulation syndrome: vertebrobasilar or posterior cerebral artery symptoms. The imaging protocol included CT of the brain on day 0 through 15 and a second CT and an MRI of the brain on day 16 through 180 after acute stroke onset. RESULTS: There were 200 patients with cerebral infarction and 28 patients with intracerebral hemorrhage. Intracerebral hemorrhage was found in 19% of patients with total anterior circulation syndrome and in no patients with lacunar syndrome (chi 2 test; P < .01 for the difference between the four clinical subgroups). Of the 200 patients with cerebral infarction, 27% had total anterior circulation, 30% partial anterior circulation, 26% lacunar, and 16% posterior circulation syndromes. CT within 2 days revealed a visible lesion in about two thirds of patients with infarctions of total or partial anterior circulation syndrome type, compared with only 22% of patients with lacunar infarction (chi 2 test; P = .02 for the difference between the four subgroups). The mean volume of the symptomatic infarction on CT within 15 days was 95 mL for total anterior circulation, 20 mL for partial anterior circulation, and 2.5 mL for lacunar syndrome (one-factor ANOVA; P = .0001). A cortical involvement of the infarction on CT day 16 through 180 was seen in 81% of patients with total anterior circulation syndrome and 58% of those with partial anterior circulation syndrome, compared with only 8% of patients with lacunar syndrome (chi 2 test; P = .0001). MRI more often than CT showed a cortical involvement of lacunar infarctions and also revealed more silent lesions. CONCLUSIONS: The described clinical subgroups significantly differed in frequencies of intracerebral hemorrhage, cortical involvement, and lesion volume on CT and MRI

Magnetic resonance imaging of the knee in chronic knee pain. A 2-year follow-up

Objective: The aim of the study was to evaluate the change over time of cartilage defects, subchondral lesions and meniscal abnormalities of the knee using magnetic resonance (MR) imaging with a 2-year interval in patients with chronic knee pain. Design: In the format of a prospective study of early osteoarthritis (OA), the signal knee (most painful at the inclusion in the study 1990) in 47 individuals, 25 women and 22 men (aged 41-57 years, median 50), with chronic knee pain, with or without radiographically determined knee OA, were examined using MR imaging on a 1.0 T imager with a 2-year interval (median 25 months, range 21-30). Cartilage defects, subchondral lesions and meniscal abnormalities were recorded and compared in blind between the examinations. Results: Five new cartilage defects and eight subchondral lesions appeared during the 2-year interval. Seven defects and seven subchondral lesions disappeared during the same time. Thirty-two out of 93 cartilage defects (34%) and 19 out of 32 subchondral lesions (59%) displayed an increase or a decrease in size over time. A meniscal abnormality appeared in three locations, and disappeared in none. In 14 out of 54 locations (26%) with a meniscal abnormality an increase or a decrease of the abnormality was recorded over time and no abnormality decreased. Conclusions: After the 2 years of observation it was possible to register, using MR imaging, the appearance, increase, decrease and disappearance of cartilage defects, subchondral lesions and meniscal abnormalities in middle-aged people with chronic knee pain. This has to be considered in studies of the natural course of knee CA as well as in studies of the intraarticular effect of pharmacological treatment aiming at cartilage repair or protection