Wearable sensor-based measures of step-up transfers are supplementary to patient-reported outcome measures following total joint arthroplasty.

PURPOSE: This study investigated the longitudinal assessment of step-up performance in patients undergoing total joint arthroplasty (TJA) and correlation with subjective patient reported outcome measures (PROMs). METHODS: In this sub-analysis of the ADAPT study, PROMs were assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Block step-up (BS) transfers were assessed by wearable-derived measures of time. 76 patients undergoing TJA were included. Subgroups were formed isolating the worst performing quartile (low functioning (LF)) from the high functioning (HF), and outcomes were compared. RESULTS: One-year post-surgery, WOMAC function demonstrated strong correlations to WOMAC pain (Pearson's r = 0.67-0.84) and moderate correlations to BS performance (Pearson's r = 0.31-0.54). Both WOMAC and BS significantly improved with a larger effect size for the HF subgroup (0.62 vs. 0.43; p < 0.05). Patients designated to the LF subgroup at 3 months had increased odds of representing the LF subgroup at 12 months (WOMAC = 19; BS = 4). WOMAC defined 18 LF patients at 12 months follow-up. BS performance identified 9 additional LF patients. CONCLUSIONS: WOMAC function scores seem pain dominated. Measures of BS performance allow assessment of otherwise hidden residual functional impairment. Lower functioning 3 months post-surgery is predictive of longer-term impairment.

Severe hip or knee osteoarthritis is a disabling condition which not only impacts patients' mobility but restricts quality of life due to constant pain and consequential lifestyle changes.Total joint arthroplasty (TJA) has developed into a successful intervention for patients with advanced hip or knee osteoarthritis.Some patients are dissatisfied after TJA due to residual functional impairment and the inclusion of performance-based tests in the post-operative evaluation and rehabilitation allows for the assessment of otherwise hidden residual impairment.Early detection of functional impairment using the repeated block step-up (BS) transfers allows to facilitate more targeted rehabilitation for better functional outcomes.

Distinct Effect of TCF4 on the NFκB Pathway in Human Primary Chondrocytes and the C20/A4 Chondrocyte Cell Line.

OBJECTIVE: Previous studies indicated a difference in crosstalk between canonical WNT pathway and nuclear factor-κB (NFκB) signaling in human and animal chondrocytes. To assess whether the differences found were dependent on cell types used, we tested the effect of WNT modulation on NFκB signaling in human primary articular chondrocytes in comparison with the immortalized human costal chondrocyte cell line C20/A4. DESIGN: We used gene expression analysis to study the effect of WNT modulation on IL1ß-induced matrix metalloproteinase (MMP) expression as well as on WNT and NFκB target gene expression. In addition, we tested the involvement of RelA and TCF4 on activation of the WNT and NFκB pathway by TCF/LEF and NFκB reporter experiments, respectively. RESULTS: We found an inhibitory effect of both induction and inhibition of WNT signaling on IL1ß-induced MMP mRNA expression in primary chondrocytes, whereas WNT modulation did not affect MMP expression in C20/A4 cells. Furthermore, TCF/LEF and NFκB reporter activation and WNT and NFκB target gene expression were regulated differentially by TCF4 and RelA in a cell type-dependent manner. Additionally, we found significantly higher mRNA and protein expression of TCF4 and RelA in C20/A4 cells in comparison with primary chondrocytes. CONCLUSIONS: We conclude that WNT modulation of NFκB is, at least in part, cell type dependent and that the observed differences are likely because of impaired sensitivity of the NFκB pathway in C20/A4 cells to modulations in WNT signaling. This might be caused by higher basal levels of TCF4 and RelA in C20/A4 cells compared to primary chondrocytes.

Danger of central pontine myelinolysis in hypotonic dehydration and recommendation for treatment.

Isotonic saline is the fluid most commonly used for treatment of asymptomatic hypotonic dehydration, but as shown in the case presented in this article, rapid increase in serum sodium may follow administration of isotonic saline, leading to the development of central pontine myelinolysis (CPM). Because the necessity of rapid correction is less, whereas the risk of CPM is greater with chronic asymptomatic hyponatremia than with acute hyponatremia, use of a half normal saline might be more appropriate than normal saline for treating certain patients with hypotonic dehydration with asymptomatic hyponatremia. The calculations indicate that half normal saline will expand the extracellular volume quite effectively, but the rate of increase in serum sodium will be considerably slower than that with normal saline.