Background: It is important to assess physical activity objectively during daily life circumstances, to understand the association between physical activity and diseases and to determine the effectiveness of interventions. Accelerometer-based physical activity monitoring seems a promising method and could potentially capture all four FITT (i.e. Frequency, Intensity, Time, Type) components of physical activity considered by the World Health Organization (WHO).Aim: To assess the four FITT components of physical activity with an accelerometer during daily life circumstances and compare with self-reported levels of physical activity in patients with knee osteoarthritis (OA) and a healthy control group.Methods: Patients (n=30) with end-stage knee OA and age-matched healthy subjects (n=30) were measured. An ambulant tri-axial accelerometer was placed onto the lateral side of the upper leg. Physical activity was measured during four consecutive days. Using algorithm-based peak detection methods in Matlab, parameters covering the four FITT components were assessed. Self-reported physical activity was assessed using the Short questionnaire to assess health enhancing physical activity (SQUASH).Results: Knee OA patients demonstrated fewer walking bouts (154 ±79 versus 215 ±65 resp.; p=0.002), step counts (4402 ±2960 steps/day versus 6943 ±2581 steps/day; p=0.001) and sit-to-stand (STS) transfers (37 ±14 versus 44 ±12; p=0.031) compared to controls. Knee OA patients demonstrated more time sitting (65 ±15% versus 57 ±10% resp.; p=0.029), less time walking (8 ±4% versus 11 ±4% resp.; p=0.014) and lower walking cadence (87 ±11steps/min versus 99 ± 8steps/min resp.; p<0.001). Accelerometer-based parameters of physical activity were moderately-strong (Pearsons’s r= 0.28-0.49) correlated to self-reported SQUASH scores.Conclusion: A single ambulant accelerometer-based physical activity monitor feasibly captures the four FITT components of physical activity and provides more insight into the actual physical activity behavior and limitations of knee OA patients in their daily life.

Osteoarthritis is one of the major causes of immobility and its current prevalence in elderly (>60 years) is 18% in women and 9.6% in men. Patients with osteoarthritis display altered movement patterns to avoid pain and overcome movement limitations in activities of daily life, such as sit-to-stand transfers. Currently, there is a lack of evidence that distinguishes effects of knee osteoarthritis on sit-to-stand performance in patients with and without obesity. The purpose of this study was therefore to investigate differences in knee and hip kinetics during sit-to-stand movement between healthy controls and lean and obese knee osteoarthritis patients. Fifty-five subjects were included in this study, distributed over three groups: healthy controls (n=22), lean knee osteoarthritis (n=14), and obese knee OA patients (n=19). All subjects were instructed to perform sit-to-stand transfers at self-selected, comfortable speed. A three-dimensional movement analysis was performed to investigate compensatory mechanisms and knee and hip kinetics during sit-to-stand movement. No difference in sit-to-stand speed was found between lean knee OA patients and healthy controls. Obese knee osteoarthritis patients, however, have reduced hip and knee range of motion, which is associated with reduced peak hip and knee moments. Reduced vertical ground reaction force in terms of body weight and increased medial ground reaction forces indicates use of compensatory mechanisms to unload the affected knee in the obese knee osteoarthritis patients. We believe that an interplay between obesity and knee osteoarthritis leads to altered biomechanics during sit-to-stand movement, rather than knee osteoarthritis alone. From this perspective, obesity might be an important target to restore healthy sit-to-stand biomechanics in obese knee OA patients.

People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal. If the publication is distributed under the terms of Article 25fa of the Dutch Copyright Act, indicated by the "Taverne" license above, please follow below link for the End User Agreement:

People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal. If the publication is distributed under the terms of Article 25fa of the Dutch Copyright Act, indicated by the "Taverne" license above, please follow below link for the End User Agreement:

No abstract

Background: Accelerometers facilitate analysis outside traditional gait laboratories. Before using these devices on a larger scale and in clinical settings, a thorough assessment of their performance in diverse populations is required. The goal of this study was to present an acceleration-based reference database for stair climbing in healthy subjects. The effect of age was studied with different parameters, such as step time up and down, asymmetry and irregularity.Methods: Our study included 100 healthy subjects, which were divided in two age groups. The group of younger adults consisted of 54 subjects with a mean age of 26 years and the group of older adults consisted of 46 subjects with a mean age of 65 years.Findings: Average step times were slightly higher ascending compared to descending. Step time difference, between ascending and descending, was significant between the young and elderly group. Irregularity and asymmetry did not diverge between the age groups. In addition, effects of age on gait parameters were found to be consistent with those reported in studies using other methodologies.Interpretation: Stair climbing based findings together with all the advantages of the device support the application of accelerometerbased gait analysis for routine clinical use and in daily life.

Background: Epileptic patients have increased risk of fractures. This is related to the traumatic event itself and to concomitant factors. Clear fracture related complaints are not always present at primary survey of these patients. This indicates a thorough primary evaluation of the complete individual post-seizure. We present a unique case of abdominal pain due to bilateral fractures fracture after an epileptic seizure.

No abstract