Biomedical subjects

O Svensson

Publications and source records attributed to O Svensson.

At least 19 recordsLinked to original sources

PubMed2006

A multidisciplinary, multifactorial intervention program reduces postoperative falls and injuries after femoral neck fracture.

INTRODUCTION: This study evaluates whether a postoperative multidisciplinary, intervention program, including systematic assessment and treatment of fall risk factors, active prevention, detection, and treatment of postoperative complications, could reduce inpatient falls and fall-related injuries after a femoral neck fracture. METHODS: A randomized, controlled trial at the orthopedic and geriatric departments at Umeå University Hospital, Sweden, included 199 patients with femoral neck fracture, aged >or=70 years. RESULTS: Twelve patients fell 18 times in the intervention group compared with 26 patients suffering 60 falls in the control group. Only one patient with dementia fell in the intervention group compared with 11 in the control group. The crude postoperative fall incidence rate was 6.29/1,000 days in the intervention group vs 16.28/1,000 days in the control group. The incidence rate ratio was 0.38 [95% confidence interval (CI): 0.20 - 0.76, p=0.006] for the total sample and 0.07 (95% CI: 0.01-0.57, p=0.013) among patients with dementia. There were no new fractures in the intervention group but four in the control group. CONCLUSION: A team applying comprehensive geriatric assessment and rehabilitation, including prevention, detection, and treatment of fall risk factors, can successfully prevent inpatient falls and injuries, even in patients with dementia.

Accidental Falls↗

PubMed2006

High-throughput sample handling and data collection at synchrotrons: embedding the ESRF into the high-throughput gene-to-structure pipeline.

An automatic data-collection system has been implemented and installed on seven insertion-device beamlines and a bending-magnet beamline at the ESRF (European Synchrotron Radiation Facility) as part of the SPINE (Structural Proteomics In Europe) development of an automated structure-determination pipeline. The system allows remote interaction with beamline-control systems and automatic sample mounting, alignment, characterization, data collection and processing. Reports of all actions taken are available for inspection via database modules and web services.

Data Collection↗

PubMed2006

Genetic mating patterns studied in pools with manipulated nest site availability in two populations of Pomatoschistus minutus.

Pomatoschistus minutus show paternal care in a resource defence mating system. We investigated the effect of nest-site availability on parasitic spawning. Each experimental pool contained four potentially nest-building males, four females and nests-sites in shortage (2) or excess (6). Both treatments were conducted in two populations; one with natural nest-sites in excess, one with a nest-site shortage. Microsatellite-DNA revealed that all nest-holders had fertilized most of the eggs they tended. Yet, 35% of the nests contained eggs fertilized by another male and 14.4% of the males had performed parasitic spawning. There was no site or treatment effect. Several females spawned in two nests, which coincided with parasitic spawnings, suggesting a cost to the nest-holder in terms of lost mating success. Nest-holders with and without eggs and non-nesting males all spawned parasitically, generating a significantly lower opportunity for sexual selection compared to if there had been no parasitic spawning.

Animals↗

PubMed2005

Greater reduction of knee than hip pain in osteoarthritis treated with naproxen, as evaluated by WOMAC and SF-36.

OBJECTIVES: To compare the improvement of hip and knee osteoarthritis during treatment with naproxen. METHODS: Men and women aged 40 to 75 years with symptomatic osteoarthritis of the knee or hip of at least three months' duration participated in a six week placebo controlled, double blind study with naproxen 500 mg twice daily as one treatment arm. Naproxen was given to 403 patients (280 knee, 123 hip) and placebo to 108 patients (75 knee, 33 hip). WOMAC (Western Ontario and McMaster Universities osteoarthritis index) 3.1 visual analogue scale and SF-36 (36 item short form health survey) were used to assess response to treatment between baseline and week 6. RESULTS: There were no differences at baseline between knee and hip osteoarthritis for any of the WOMAC subscales or SF-36 domains. Improvement was between 4 and 7 mm greater for knee than for hip for all WOMAC subscales (pain, delta = 4.7 mm (p = 0.03); stiffness, delta = 6.6 mm (p = 0.004); function, delta = 4.8 mm (p = 0.06)). Effect size was about 0.8 for all WOMAC subscales for the knee and between 0.5 and 0.6 for the hip. Knee patients treated with naproxen improved 4.6 (p = 0.033) more than hip patients for SF-36 bodily pain and 10.3 (p = 0.014) more for SF-36 role-physical. CONCLUSIONS: Patients with knee osteoarthritis improved more with naproxen treatment than patients with hip osteoarthritis, as monitored by WOMAC and the SF-36 domains bodily pain and role-physical. These findings warrant further investigation and strongly suggest that efficacy of treatment of osteoarthritis of knee and hip should be evaluated separately.

Adult↗

PubMed2004

A randomised, placebo controlled, comparative trial of the gastrointestinal safety and efficacy of AZD3582 versus naproxen in osteoarthritis.

OBJECTIVE: To evaluate the gastrointestinal safety and efficacy of the COX inhibiting nitric oxide donator AZD3582 in patients with hip or knee osteoarthritis. METHODS: 970 patients were randomised (7:7:2) to AZD3582 750 mg twice daily, naproxen 500 mg twice daily, or placebo twice daily in a double blind study. The primary end point was the six week incidence of endoscopic gastroduodenal ulcers (diameter > or =3 mm). Overall damage measured on the Lanza scale was a secondary end point. Safety and tolerability assessments included endoscopic upper gastrointestinal erosions and the gastrointestinal symptom rating scale (GSRS). Efficacy was primarily assessed by WOMAC. RESULTS: The incidence of ulcers with AZD3582 was 9.7% and with naproxen 13.7% (p = 0.07, NS), v 0% on placebo. The incidence of Lanza scores >2 was higher with naproxen (43.7%) than with AZD3582 (32.2%) (p<0.001). Compared with baseline, significantly fewer ulcers and erosions developed in stomach and stomach/duodenum combined, and fewer erosions developed in stomach, duodenum, and both combined on AZD3582 than on naproxen. GSRS reflux and abdominal pain subscale scores were lower for AZD3582 than for naproxen but there was no difference for indigestion, constipation, and diarrhoea. AZD3582 was as effective as naproxen at improving WOMAC scores. Both agents were well tolerated, with no significant effects on blood pressure. CONCLUSIONS: At doses with similar efficacy in relieving osteoarthritis symptoms, the primary end point of six week endoscopic gastroduodenal ulcer incidence was not significantly different between AZD3582 and naproxen. Most secondary endoscopic gastrointestinal end points favoured AZD3582.

Adult↗

PubMed2003

Responsiveness of the EuroQol (EQ 5-D) and the SF-36 in elderly patients with displaced femoral neck fractures.

OBJECTIVES: To evaluate the responsiveness of the EuroQol (EQ-5D) and Short-Form 36 (SF-36) instruments, i.e. their ability to capture clinically important changes, in elderly patients with a displaced femoral neck fracture. The study was part of a prospective randomised study comparing two different surgical procedures, internal fixation (IF) and total hip replacement (THP). SETTING: University hospital. PATIENTS: A total of 110 patients, mean age 80 years with an acute displaced femoral neck fracture (Garden III and IV). The inclusion criteria were age > or = 70, absence of severe cognitive dysfunction, independent living status and independent walking capability. INTERVENTION: The patients were randomised to IF or to a THR. MAIN OUTCOME MEASUREMENTS: Health-related quality of life according to EQ-5D and SF-36. Responsiveness measured by the ability of the EQ-5D and the SF-36 to detect clinically relevant differences in the study population according to an external criterion (EC) for outcome (good or less good clinical outcome). Responsiveness was measured in terms of change scores, standardised effect size (SES) and standardised response mean (SRM). RESULTS: The rated prefracture EQ-5D(index) scores and SF-36 scores showed good correspondence with the scores of age-matched Swedish reference populations. The relationship between the EC and EQ-5D(index) score and the SF-36 global score showed significant differences in both comparisons (p < 0.001). The responsiveness expressed with the SES and SRM were large for both the EQ-5D (1.37 and 0.90, respectively) and for the SF-36 global score (0.89 and 0.82, respectively). The correlation between the change scores for the SF-36 global score and the EQ-5D was 0.39 (p < 0.001). CONCLUSION: The results showed high responsiveness for both the EQ-5D and the SF-36, indicating that both instruments are suitable for use as outcome measures in clinical trials in elderly hip fracture patients.

Accidental Falls↗

PubMed2003

Sexually selected nest-building--Pomatoschistus minutus males build smaller nest-openings in the presence of sneaker males.

Both natural selection and sexual selection may act on nest-building. We tested experimentally how different regimes of egg-predation and male-male competition influence nest-building before mating, using the marine fish sand goby, Pomatoschistus minutus. Males with sneaker males present built the smallest nest-openings, smaller than males held alone or with Pomatoschistus microps males (which may predate eggs and compete over nest-sites but not compete over fertilizations). Males with visual access to other nest-building males tended also to build smaller openings than males held alone or with P. microps. Males with egg-predators present built nests with openings not differing significantly from any other treatment. Our results indicate that the small nest-openings found in the sneaker male treatment are sexually selected through protection against sneaking or by female choice. Across treatments, time span before a male started to build his nest also explained variation in nest-opening width; males starting late built larger nest-openings.

Adaptation, Physiological↗

PubMed2003

Internal fixation compared with total hip replacement for displaced femoral neck fractures in the elderly. A randomised, controlled trial.

The treatment algorithms for displaced fractures of the femoral neck need to be improved if we are to reduce the need for secondary surgery. We have studied 102 patients of mean age 80 years, with an acute displaced fracture of the femoral neck. They were randomly placed into two groups, treated either by internal fixation (IF) with two cannulated screws or total hip replacement (THR). None showed severe cognitive dysfunction, all were able to walk independently, and all lived in their own home. They were reviewed at four, 12 and 24 months after surgery. Outcome measurements included hip complications, revision surgery, hip function according to Charnley and the health-related quality of life (HRQoL) according to EuroQol (EQ-5D). The failure rate after 24 months was higher in the IF group than in the THR group with regard to hip complications (36% and 4%, respectively; p < 0.001), and the number of revision procedures (42% and 4%, p < 0.001). Hip function was significantly better in the THR group at all follow-up reviews regarding pain (p < 0.005), movement (p < 0.05 except at 4 months) and walking (p < 0.05). The reduction in HRQoL (EQ-5D index score) was also significantly lower in the THR group than in the IF group, comparing the pre-fracture situation with that at all follow-up reviews (p < 0.05). The results of our study strongly suggest that THR provides a better outcome than IF for elderly, relatively healthy, lucid patients with a displaced fracture of the femoral neck.

Aged↗

PubMed2002

Automation of the collection and processing of X-ray diffraction data -- a generic approach.

With modern detectors and synchrotron sources, it is now routine to collect complete data sets in 10-30 min. To make the most efficient use of these resources, it is desirable to automate the collection and processing of the diffraction data, ideally to a level at which multiple data sets can be acquired without any intervention. A scheme is described to allow fully automated data collection and processing. The design is modular, so that it can easily be interfaced with different beamline-control programs and different data-processing programs. An expert system provides a communication path between the data-processing software and the beamline-control software and takes decisions about the data collection based on project information provided by the user and experimental data provided by the data-processing program.

Algorithms↗

PubMed2002

Patient expectation and satisfaction in revision total hip arthroplasty.

Sixty-six consecutive revision total hip arthroplasty patients were asked about their expectations regarding future pain and walking ability. Expectations were high, regardless of background factors: 92% expected to have much less pain, and 82% expected the same walking ability as after the primary arthroplasty or a much improved walking ability. Of the patients, 56% stated a non-surgeon-related origin of expectations, 7% were uncertain, and 37% said expectations derived from the surgeon. At 1 year, Harris hip score had increased from a median 45 to 77 points, but only 69% and 55% said that their expectations had been fulfilled to a very large or rather large extent regarding pain and walking ability. The only predictor of fulfilled expectations was absence of complications (odds ratio, 4.8; 95% confidence interval, 1.1-20.8). Patient satisfaction was only moderate; 63% were very or rather satisfied with a moderate correlation (0.46-0.47) between satisfaction and fulfilled expectations. Patients with a poor preoperative hip condition generally were more satisfied (odds ratio, 5.0; 95% confidence interval, 1.4-17.9), and the most important reason probably was an improved walking ability (r = 0.64). Patient dissatisfaction may originate from unrealistic expectations. At preoperative consultation, it is recommended that the surgeon discuss the revision patient's expectations, especially regarding future walking ability, and inform the patient about the fundamental prognostic differences between revision and primary hip arthroplasty.

Aged↗

PubMed2002

Observer reliability in the arthroscopic classification of osteoarthritis of the knee.

We studied 19 videotaped knee arthroscopies in 19 patients with mild to moderate osteoarthritis (OA) of the knee in order to compare the intraobserver and interobserver reliability and the patterns of disagreement between four orthopaedic surgeons. The classifications of OA of Collins, Outerbridge and the French Society of Arthroscopy were used. Intraobserver and interobserver agreements using kappa measures were 0.42 to 0.66 and 0.43 to 0.49, respectively. Only 6% to 8% of paired intraobserver classifications differed by more than one category. Observer-specific disagreement was evident both within and between observers. A small, but significant, occasional variation was also seen. Although reliability may improve by an analysis of disagreement, it appears that the arthroscopic grading of early osteoarthritic lesions is inexact.

Adult↗

PubMed2001

[Arthrosis among the elderly. Conservative therapy as a first choice].

Osteoarthritis, a collective term for late joint destruction, is one of the most common causes of disability among the elderly. Since the pathogenesis is unknown, there is no causal therapy. Treatment is therefore primarily conservative and focused on pain control. However, among elderly people, overall results after joint replacement are excellent. Moreover, outcome is continually improving, especially thanks to national quality registers.

Aged↗

PubMed2001

Otoacoustic emissions and improved pass/fail separation using wavelet analysis and time windowing.

A new method is presented for the purpose of improving pass/fail separation during transient evoked otoacoustic emission (TEOAE) hearing screening. The method combines signal decomposition in scales using the discrete wavelet transform, non-linear denoising and scale-dependent time windowing. The cross-correlation coefficient between two subaveraged, processed TEOAE signals is used as a pass/fail criterion and assessed in relation to the pure-tone, mean hearing level. The performance is presented in terms of receiver operating characteristics for a database of 5,214 individuals. The results show that the specificity improves from 68% to 83% at a sensitivity of 90% when compared with the conventional wave reproducibility parameter.

Hearing Loss↗

PubMed2001

Effect of load on articular cartilage matrix and the development of guinea-pig osteoarthritis.

OBJECTIVE: To study the biochemical changes in the early development of primary guinea-pig knee osteoarthritis (OA) and its dependence on load. METHODS: Load distribution was modified with below-knee amputation or femur valgus osteotomy in 9-month-old guinea-pigs. Soft tissue sham operated animals served as controls. The composition of uncalcified and calcified articular cartilage at the medial and lateral tibial condyle was studied by analysing small and large proteoglycans (PG) by gel electrophoresis and sulfation pattern with high-performance liquid chromatography. Collagen concentration was also determined. RESULTS: The articular surfaces with a presumed higher load after surgery had a slight, but consistent, higher water content. Decreased load-on the ipsilateral medial condyle after femur osteotomy, and on the ipsilateral medial and lateral condyles following tibia amputation-was associated with an increased concentration of PGs, while this concentration decreased in condyles with increased load. Collagen concentration followed a similar pattern in the osteotomy group. In the amputated animals collagen concentration went down in all condyles, regardless of change of load. The aggregability and proportion of large and small PGs, the concentration of hyaluronan and the sulfation pattern of chondroitin sulfate was not affected by load. No consistent changes in PG, collagen or HA concentration, HA aggregability or sulfation pattern were seen in the calcified cartilage. CONCLUSIONS: Primary guinea-pig knee OA is a reproducible model similar to human OA. It develops slowly and biochemical changes seem to appear before the morphological lesions become evident. The biochemical events are affected by load redistribution and correlate closely to morphological changes. These changes eventually result in a cartilage devoid in aggrecan, as also has been demonstrated in advanced human OA. All of this makes primary guinea-pig OA a suitable model for studying early OA changes.

Animals↗

PubMed2001

Ultrasound for diagnosis of infection in revision total hip arthroplasty.

Eighty consecutive patients (85 hips; 43 women; median age, 74 years [range, 33-90 years]) underwent a revision total hip arthroplasty. Preoperatively and guided by ultrasound, biopsy specimens of the joint pseudocapsule were taken, and joint fluid was aspirated for culture. Capsule morphology was investigated with light microscopy. When septic loosening was defined as 2 intraoperative cultures yielding the same microorganism, the prevalence was 12%. Sensitivity of the capsule biopsy cultures was 67%; specificity, 68%; positive predictive value, 22%; and negative predictive value, 94%. Joint fluid was often sparse and always falsely sterile. One specimen from a hip with septic loosening showed histologic changes (> or =3 foci, each with > or =3 plasma cells/high-power field) consistent with chronic infection. The remaining 8 septic loosenings eluded histologic detection, yielding 11% sensitivity. All aseptic loosenings were classified correctly (specificity 100%). Positive and negative predictive values were 100% and 89%. Ultrasound-guided aspiration and capsule biopsy with cultures and histology does not seem to be sufficiently accurate in the preoperative diagnosis of infected total hip arthroplasty.

Adult↗

PubMed2001

Early loosening of the stemmed McMinn cup.

The stemmed McMinn cup was used in 26 acetabular reconstructions (median age, 59 [range, 33-85 years]; 21 women) at 5 orthopaedic centers in Sweden between 1995 and 1998. Of the patients, 24 (92%) had severe bone defects (Gustilo-Pasternak grade 3 and 4). At a clinical and radiographic follow-up of median 3 years (range, 1-5 years), 4 (17%) cups were rerevised at 1 (2 cups), 2, and 3 years owing to symptomatic aseptic loosening. Another 8 cups (40%) were radiographically definitely loose and 1 (5%) was probably so. With an overall mechanical failure rate (rerevised plus definitely loose devices) of 43.8% at a minimum 3-year follow-up, the stemmed McMinn cup does not seem to be a reliable solution in acetabular reconstruction.

Acetabulum↗

PubMed2001

Collagen and fibronectin binding in experimental staphylococcal osteomyelitis.

A new mouse model of locally induced osteomyelitis was used to study the importance for pathogenicity of the specific binding ability of Staphylococcus aureus to collagen and fibronectin. This method appears to be convenient, reproducible, and suitable for large-scale experiments. In contrast to previous studies in experimental arthritis and endocarditis models, no difference in infection rates was found between the strains deficient in binding to collagen compared with the corresponding adherence-proficient strains. However, fibronectin binding ability in this model, in contrast to the endocarditis model, is thought to enhance the microorganisms' capacity to establish an infection. Infections caused by the fibronectin-binding strain also are thought to be clinically more aggressive than those caused by the nonbinding strain. Specific adherence mechanisms are thought to be operative in the pathogenesis of biomaterial associated osteomyelitis, and an improved understanding of such mechanisms may have an important prophylactic and therapeutic impact.

Adhesins, Bacterial↗

PubMed2000

[Malpractice in connection with radius fractures must be reduced. Clear guidelines for treatment and follow-up are required].

PSR handles the vast majority of malpractice injuries in Sweden. PSR is a claims handling company which settles claims for malpractice on behalf of the insurance company owned by the Swedish county councils: the County Councils Mutual Insurance Company. A central issue in the law regulating patient injuries in Swedish health care is to define injuries that could have been avoided if a certain therapeutic/diagnostic procedure or a more appropriate method had been utilized. PSR arranged a multiprofessional conference regarding guidelines to decrease the number of malpractice injuries in the treatment of distal radius fractures. Among the most important issues defined were: To improve and standardize diagnostic imaging Patient information Early decision making in surgery and physical/occupational therapy A more well-defined indication for surgery, in which type of trauma, biological age and functional demands are considered in addition to radiographs Less stereotyped thinking in follow-up Controlled randomized trials.

Clinical Competence↗