Showing papers by "L. Stefan Lohmander published in 2012"

High tibial osteotomy in Sweden, 1998-2007: a population-based study of the use and rate of revision to knee arthroplasty.

Abstract: Background and purpose Most studies on high tibial osteotomies (HTOs) have been hospital-based and have included a limited number of patients We evaluated the use and outcome—expressed as rate of revision to knee arthroplasty—of HTO performed in Sweden with 9 million inhabitants, 1998–2007 Patients and methods 3, 161 HTO procedures on patients 30 years or older (69% men) who were operated on for knee osteoarthritis in Sweden, 1998–2007, were identified through the inpatient and outpatient care registers of the Swedish National Board of Health and Welfare Pertinent data were verified through surgical records Conversions of HTO to knee arthroplasty before 2010 were identified through the Swedish Knee Arthroplasty Register (SKAR) The 10-year survival was determined using revision to an arthroplasty as the endpoint Results The number of HTOs decreased by one third between 1998 and 2007, from 388 operations a year to 257 a year Most of the HTOs were performed with open wedge osteotomy using external fix

Effect of leisure time physical activity on severe knee or hip osteoarthritis leading to total joint replacement: a population-based prospective cohort study

Abstract: Studies on leisure time physical activity as risk factor or protective factor for knee or hip osteoarthritis (OA) show divergent results. Longitudinal prospective studies are needed to clarify the association of physical activity with future OA. The aim was to explore in a prospective population-based cohort study the influence of leisure time physical activity on severe knee or hip OA, defined as knee or hip replacement due to OA. Leisure time physical activity was reported by 28320 participants (mean age 58 years (SD 7.6), 60% women) at baseline. An overall leisure time physical activity score, taking both duration and intensity of physical activities into account, was created. The most commonly reported activities were also used for analysis. The incidence of knee or hip replacement due to OA over 11 years was monitored by linkage with the Swedish hospital discharge register. Cox’s proportional hazards model (crude and adjusted for potential confounding factors) was used to assess the incidence of total joint replacement, or osteotomy (knee), in separate analyses of leisure time physical activity. There was no significant overall association between leisure time physical activity and risk for knee or hip replacement due to OA over the 11-year observation time. For women only, the adjusted RR (95% CI) for hip replacement was 0.66 (0.48, 0.89) (fourth vs. first quartile), indicating a lower risk of hip replacement in those with the highest compared with the lowest physical activity. The most commonly reported activities were walking, bicycling, using stairs, and gardening. Walking was associated with a lower risk of hip replacement (adjusted RR 0.76 (95% CI 0.61, 0.94), specifically for women (adjusted RR 0.75 (95% CI 0.57, 0.98)). In this population-based study of middle-aged men and women, leisure time physical activity showed no consistent overall relationship with incidence of severe knee or hip OA, defined as joint replacement due to OA, over 11 years. For women, higher leisure time physical activity may have a protective role for the incidence of hip replacement. Walking may have a protective role for hip replacement, specifically for women.

A population-based study of the use and rate of revision to knee arthroplasty

Abstract: Open Access This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the source is credited. DOI 10.3109/17453674.2012.688725 Background and purpose Most studies on high tibial osteotomies (HTOs) have been hospital-based and have included a limited number of patients. We evaluated the use and outcome— expressed as rate of revision to knee arthroplasty—of HTO performed in Sweden with 9 million inhabitants, 1998–2007. Patients and methods 3, 161 HTO procedures on patients 30 years or older (69% men) who were operated on for knee osteoarthritis in Sweden, 1998–2007, were identified through the inpatient and outpatient care registers of the Swedish National Board of Health and Welfare. Pertinent data were verified through surgical records. Conversions of HTO to knee arthroplasty before 2010 were identified through the Swedish Knee Arthroplasty Register (SKAR). The 10-year survival was determined using revision to an arthroplasty as the endpoint. Results The number of HTOs decreased by one third between 1998 and 2007, from 388 operations a year to 257 a year. Most of the HTOs were performed with open wedge osteotomy using external fixation. The cumulative revision rate at 10 years was 30% (95% CI: 28–32). The risk of revision increased with increasing age and was higher in women than in men (RR = 1.3, CI: 1.1–1.5). Interpretation If being without an artificial joint implant is considered to be beneficial, then HTO is an excellent alternative to knee arthroplasty in younger and/or physically active patients suffering from knee osteoarthritis.

Aggrecanase cleavage in juvenile idiopathic arthritis patients is minimally detected in the aggrecan interglobular domain but robust at the aggrecan C-terminus

Abstract: OBJECTIVE: To understand aggrecan degradation in juvenile idiopathic arthritis (JIA), the pattern and abundance of aggrecan fragments in synovial fluid aspirates from JIA patients were analysed and compared with aggrecan fragments in synovial fluids from patients with other arthritides, juvenile knee injury and a knee-healthy reference group. METHODS: The concentration of sulphated glycosaminoglycans in synovial fluid was measured by the Alcian blue precipitation assay. Aggrecan fragments were purified by dissociative CsCl density gradient centrifugation, deglycosylated and analysed by Western blot using antibodies specific for either aggrecanase-derived ARGS, SELE and KEEE neoepitopes, or the aggrecan G3-domain. RESULTS: The concentration of sulphated glycosaminoglycans in JIA synovial fluids was significantly lower compared with the levels in fluids from OA (P<0.001), juvenile knee injury (P=0.006) and knee-healthy reference (P=0.022) groups. Western blot analysis detected KEEE, SELE, and G3 fragments generated by aggrecanase cleavage in the chondroitin sulphate-rich region of JIA aggrecan. The pattern of JIA aggrecan fragments was not identical to that in synovial fluids pooled from OA patients, although there were notable similarities. Surprisingly, aggrecanase-derived ARGS fragments were barely detectable in the JIA synovial fluids, in marked contrast to the levels of ARGS fragments in OA synovial fluids. CONCLUSIONS: Aggrecanases appear to cleave minimally in the interglobular domain of aggrecan in JIA patients despite robust levels of cleavage in aggrecan's chondroitin-sulphate rich region. The results suggest that unlike other arthritides, aggrecanase cleavage in the aggrecan interglobular domain might not be a major pathogenic event in JIA. © 2012 American College of Rheumatology.

More on Treatment for Acute Anterior Cruciate Ligament Tears

Abstract: To the Editor: We previously published results of our randomized trial of treatment for anterior cruciate ligament tears (July 22, 2010, issue).1 In Table 3 of that article, which shows primary, secondary, and exploratory outcomes at 2 years, the P values and confidence intervals were calculated in compliance with the “Points to Consider on Adjustment for Baseline Covariates,” in the European Medicines Agency guidelines a distinction that was not stated in the article. Accordingly, the P values were adjusted for baseline value, whereas the unadjusted confidence intervals were calculated by maximum-likelihood estimation. There were no significant between-group differences in either . . .