Factors predicting patient satisfaction 2 years after total knee arthroplasty for osteoarthritis

Objective

To identify factors predicting patient satisfaction 2 years after total knee arthroplasty (TKA) for osteoarthritis.

Methods

Prospective multicenter study of patients followed up for 2 years after TKA for osteoarthritis. We evaluated pain and function (Lequesne index and WOMAC) at baseline and after 2 years. After 2 years, the patients rated their satisfaction as a percentage, with values greater than 50% defining good satisfaction. Factors associated with good satisfaction were identified by univariate analyses followed by multivariate analysis.

Results

Of 299 patients, 264 completed the study (26 were lost to follow-up, six died, and three refused the 2-year evaluation), including 237 (89.8%) with satisfaction scores greater than 50%. Highly significant improvements were found after 2 years versus baseline in the Lequesne index (7.9 vs. 14.5, P < 0.0001) and WOMAC index (26.3 vs. 51.3, P < 0.0001). There were 26 (9.8%) complications. Factors significantly associated with good satisfaction in the multivariate model were absence of complications (P = 0.004), body mass index less than 27 kg/m² (P = 0.015), high radiological joint narrowing score (P = 0.038), age greater or equal to 70 years (P = 0.038), and absence of depression at the 2-year evaluation (P = 0.002).

Conclusion

We report the first prospective multicenter study done in France to assess pain and function in a large number of patients treated with TKA for osteoarthritis. Our results indicate a high success rate. We identified three factors that predict patient satisfaction and can be assessed before surgery (age greater than 70 years, absence of obesity, and severe joint space narrowing).     

Interaction between anandamide and sphingosine-1-phosphate in mediating vasorelaxation in rat coronary artery

Background and purpose:

This study establishes a pharmacokinetic/pharmacodynamic (PK/PD) model to describe the time course and in vivo mechanisms of action of the antinociceptive effects of lumiracoxib, evaluated by the thermal hyperalgesia test in rats.

Experimental approach:

Female Wistar fasted rats were injected s.c. with saline or carrageenan in the right hind paw, followed by either 0, 1, 3, 10 or 30 mg·kg⁻¹ of oral lumiracoxib at the time of carrageenan injection (experiment I), or 0, 10 or 30 mg·kg⁻¹ oral lumiracoxib at 4 h after carrageenan injection (experiment II). Antihyperalgesic responses were measured as latency time (LT) to a thermal stimulus. PK/PD modelling of the antinociceptive response was performed using the population approach with NONMEM VI.

Results:

A two-compartment model described the plasma disposition. A first-order model, including lag time and decreased relative bioavailability as a function of the dose, described the absorption process. The response model was: LT=LT₀/(1 +MED). LT₀ is the baseline response, and MED represents the level of inflammatory mediators. The time course of MED was assumed to be equivalent to the predicted profile of COX-2 activity and was modelled according to an indirect response model with a time variant synthesis rate. Drug effects were described as a reversible inhibition of the COX-2 activity. The in vivo estimate of the dissociation equilibrium constant of the COX-2-lumiracoxib complex was 0.24 µg·mL⁻¹.

Conclusions:

The model developed appropriately described the time course of pharmacological responses to lumiracoxib, in terms of its mechanism of action and pharmacokinetics.     

A genetic variant of NLRP1 gene is associated with asbestos body burden in patients with malignant pleural mesothelioma

The presence of asbestos bodies (ABs) in lung parenchyma is considered a histopathologic hallmark of past exposure to asbestos fibers, of which there was a population of longer fibers. The mechanisms underlying AB formation are complex, involving inflammatory responses and iron (Fe) metabolism. Thus, the responsiveness to AB formation is variable, with some individuals appearing to be poor AB formers. The aim of this study was to disclose the possible role of genetic variants of genes encoding inflammasome and iron metabolism proteins in the ability to form ABs in a population of 81 individuals from North East Italy, who died after having developed malignant pleural mesothelioma (MPM). This study included 86 genetic variants distributed in 10 genes involved in Fe metabolism and 7 genetic variants in two genes encoding for inflammasome molecules. Genotypes/haplotypes were compared according to the number of lung ABs. Data showed that the NLRP1 rs12150220 missense variant (H155L) was significantly correlated with numbers of ABs in MPM patients. Specifically, a low number of ABs was detected in individuals carrying the NLRP1 rs12150220 A/T genotype. Our findings suggest that the NLRP1 inflammasome might contribute in the development of lung ABs. It is postulated that the NLRP1 missense variant may be considered as one of the possible host genetic factors contributing to individual variability in coating efficiency, which needs to be taken when assessing occupational exposure to asbestos.     

Proximal femoral focal deficiency: radiologic analysis of 49 cases

Proximal femoral focal deficiency, an uncommon congenital anomaly, necessitates early radiologic classification for surgical planning and treatment. Objective radiographic criteria, including femoral length index, acetabular depth index, acetabular angle index, and shape of the proximal femur were determined in 49 patients before cartilaginous ossification of the femoral capital epiphysis; final classification was based on follow-up radiographs or findings at arthrography or surgery. These parameters were analyzed to determine the accuracy and contributions of each in classification. Correct classification into one of three groups was possible in 86% of cases with use of three of the parameters: femoral length index, acetabular depth index, and shape of the proximal femur. The acetabular angle was found to contribute insignificantly to classification. Magnetic resonance imaging, used in only one case, depicted the nonossified cartilaginous femoral capital epiphysis, thus obviating the need for invasive diagnostic procedures and facilitating early classification.