To investigate factors associated with fulfilment of expectations towards paid employment after total hip/knee arthroplasty (THA/TKA). Cohort study including preoperatively employed patients aged... Show moreTo investigate factors associated with fulfilment of expectations towards paid employment after total hip/knee arthroplasty (THA/TKA). Cohort study including preoperatively employed patients aged 18-64 scheduled for THA/TKA. Expectations were collected preoperatively, and 6 and 12 months postoperatively with the paid employment item of the Hospitalfor-Special-Surgery Expectations Surveys (back-to-normal = 1; large improvement = 2; moderate improvement = 3; slight improvement = 4; not applicable = 5). Patients scoring not applicable were excluded. Fulfilment was calculated by subtracting preoperative from postoperative scores (< 0: unfulfilled; = 0: fulfilled). Multivariable logistic regression analyses were conducted separately for THA/TKA at 6 and 12 months postoperatively. Six months postoperatively, 75% of THA patients (n = 237/ n = 316) and 72% of TKA patients (n = 211/n = 294) had fulfilled expectations. Older age (TKA:OR 1.08, 95% CI 1.01-1.15) and better postoperative physical functioning (THA:OR 1.10, 95% CI 1.06-1.14; TKA:OR 1.03, 95% CI 1.01-1.06) increased the likelihood of fulfilment. Physical work tasks (THA:OR 0.12, 95% CI 0.03-0.44), preoperative sick leave (TKA:OR 0.33, 95% CI 0.17-0.65), and difficulties at work (THA:OR 0.10, 95% CI 0.03- 0.35; TKA:OR 0.41, 95% CI 0.17-0.98) decreased the likelihood of fulfilment. Twelve months postoperatively similar risk factors were found. Three out of four working-age THA/TKA patients had fulfilled expectations towards paid employment at 6 months postoperatively. Preoperative factors associated with fulfilment were older age, mental work tasks, no sick leave, postoperative factors were better physical functioning, and no perceived difficulties at work. Show less
The influence of sex on preoperative expectations and their fulfillment following total hip and knee arthroplasty (THA/TKA) remains unexplored. We investigated differences between men and women in... Show moreThe influence of sex on preoperative expectations and their fulfillment following total hip and knee arthroplasty (THA/TKA) remains unexplored. We investigated differences between men and women in perceived preoperative expectations on the outcome of THA/TKA and their fulfillment 1 year postoperatively. We performed a cohort study. Expectations were collected preoperatively and 1 year postoperatively using the Hospital for Special Surgery Hip/Knee Replacement Expectations Surveys (HSS-HRES/KRES; not applicable = 0, applicable: back to normal = 1, much = 2/moderate = 3/slight improvement = 4). Fulfillment of expectations was calculated by subtracting preoperative from postoperative scores (score < 0:unfulfilled; score >= 0:fulfilled). We included patients with "applicable" expectations. Chi-square and ordinal regression were used to compare expectations and fulfillment regarding sex. 2333 THA (62% women) and 2398 TKA (65% women) patients were included. 77% of THA and 76% of TKA patients completed the HSS-HRES/HSS-KRES both preoperatively and 1 year postoperatively. Men more often perceived items as "applicable", with differences in 9/20 (HSS-HRES) and 9/19 (HSS-KRES) preoperative items and, respectively, 12/20 (HSS-HRES) and 10/19 (HSS-KRES) postoperative items. The largest differences (> 10%) were found in sexual activity and working ability. 16/20 (HSS-HRES) and 14/19 (HSS-KRES) items showed an increased probability of having higher preoperative expectations of >= 10%, in favor of men. In all items, 60% of the respondents indicated that their expectation was fulfilled. Differences were observed in 16/20 (HSS-HRES) and 6/19 (HSS-KRES) items in favor of men. Sex differences were present in expectations and fulfillment, with higher applicability of items, preoperative expectations and fulfillment in men, especially on items related to functional activities. Trial registration: Trial-ID NTR3348. Show less
Importance: Aseptic loosening is a major cause of failure for unicondylar knee arthroplasty (UKA). In total knee arthroplasty (TKA), early migration as measured with radiostereometric analysis (RSA... Show moreImportance: Aseptic loosening is a major cause of failure for unicondylar knee arthroplasty (UKA). In total knee arthroplasty (TKA), early migration as measured with radiostereometric analysis (RSA) is a strong predictor of late revision for aseptic loosening of the tibial component. Migration in the first two years provides information on the fixation of an implant. However, the migration pattern of UKAs has not been systematically determined, and it is unclear if the migration pattern of UKAs is similar to that of TKAs. Therefore, the present meta-analysis aims to evaluate the migration patterns of tibial components of UKAs. Evidence review: All RSA studies reporting on migration at two or more postoperative time-points following UKA were included. Pubmed, Web of Science, Cochrane, and Embase were searched up to April 2021. The risk of bias was assessed using the methodological score of the Assessment of Quality in Lower Limb Arthroplasty tool. All phases of the review were performed by two reviewers independently. A random-effects model was applied to pool the migration data. Findings: The literature search yielded 3,187 hits, of which ten studies were included, comprising 13 study groups and 381 UKAs. The majority of the early migration occurred in the first 6 months postoperatively followed by a period of very little migration, similar to what is reported for TKAs. The pooled mean migration expressed as the maximum total point motion of all UKAs at 3 months, 6 months, 1 year, and 2 years was 0.43 mm (95% CI 0.38???0.48), 0.54 mm (95% CI 0.40???0.67), 0.59 mm (95% CI 0.52???0.66), and 0.61 mm (95% CI 0.55???0.68), respectively. Migration at one year and two years was higher than migration of TKAs as reported in previous studies. All-polyethylene UKAs migrated more at one year (0.69 mm; 95% CI 0.58???0.80) than metal-backed UKAs (0.52 mm; 95% CI 0.46???0.58). Conclusions and relevance: The migration pattern of UKAs is comparable with that of TKAs in the first two years as both types of implants show initial migration in the first few months and very little migration thereafter. However, UKAs had higher migration at 1-year and 2-year follow-up. Show less
This dissertation explores the ability of commercial parties to obtain the very thing they bargained for under the contract law of the Netherlands, Singapore and China. It does so by analysing the... Show moreThis dissertation explores the ability of commercial parties to obtain the very thing they bargained for under the contract law of the Netherlands, Singapore and China. It does so by analysing the extent to which respective contract law principles balance out the interests of parties to a commercial sales contract in the principles surrounding the enforceability of performance obligations. Attention is also paid to the approaches taken by global and regional sales and contract law instruments. Show less
In this thesis, in close collaboration with my research colleagues, I have shown that T-cell recruitment in both spontaneous autoimmune diabetes and islet transplantation requires presence... Show more In this thesis, in close collaboration with my research colleagues, I have shown that T-cell recruitment in both spontaneous autoimmune diabetes and islet transplantation requires presence of a cognate antigen, which could be used as an argument in favour of further pursuing antigen-specific therapies. We have shown that recurrent diabetes in an islet transplantation model is driven by memory auto reactive T-cells and this latter finding has contributed to the present testing of immune suppressive drugs that indeed address recurrent autoimmunity, to improve outcome in clinical islet transplantation. We have designed and tested a novel auto-immune diabetes cell line tracing model for future testing of the regenerative capacity of islet-cells. We have shown that immune evasion protects beta-cells from autoimmune T-cell attack in vivo. Currently different immune evasion techniques, such as islet encapsulation are being tested in the clinic. We have shown that recall immunity is preserved in spite of high dose anti-CD3 treatment, adding to the safety of high dose anti-CD3 treatment as an immune modulator agent in the treatment of T1DM. Show less