Usability and preliminary effectiveness of an app-based physical activity and education program for people with hip or knee osteoarthritis - a pilot randomized controlled trial.

BACKGROUND: Hip and knee osteoarthritis (OA) are highly prevalent worldwide. The guidelines recommend physical activity and education as the core treatments for osteoarthritis. Digital health has the potential to engage people in physical activity and disease management. Therefore, we conducted a pilot trial to assess the usability and preliminary effectiveness of an app-based physical activity and education program (Join2Move) compared to usual care for people with hip and/or knee OA in Germany. METHODS: A randomized controlled pilot study was conducted. Individuals with diagnosed or self-reported knee and hip OA were included. Allocation to the intervention or control group was randomized. The intervention group received the Join2Move program. The Join2Move program was previously developed as a website and evaluated in the Netherlands. For the current study, the program was translated and adapted to the German context and adjusted from a website to an app. The control group received usual care. The primary outcomes were usability and preliminary effectiveness (pain and physical functioning). Measurements were taken at baseline and at twelve weeks. The data analysis was performed using SPSS (IBM SPSS Statistics 29.0). RESULTS: Sixty participants, with a mean age of 61.9 (SD ± 7.2) years, were allocated to the intervention (n = 32) or the control group (n = 28) and included in the analysis. The majority of participants had knee OA (68%), and 12% had hip and knee OA. The dropout rate was n = 11 (18%). No adverse events were reported. Usability was rated as acceptable (mean System Usability Scale = 71.3/100) with a wide range (32.5 to 100). Statistically significant between-group differences were found only for pain (mean difference 8.52 (95% CI 1.01 to 16.04), p = 0.027). CONCLUSIONS: Join2Move demonstrated acceptable usability. The preliminary results of the pilot trial indicate the potential of a stand-alone app for the treatment of patients with hip or knee OA. However, the acceptable usability of Join2Move limits its recommendation for everyone. There appears to be room for improvement in app usability and in identifying patients for whom the app is suitable and the right time to use a stand-alone app. TRIAL REGISTRATION: German Clinical Trials Register DRKS00027164 .

Anomalous Dispersion with Edges in the Soft X-ray Region: First Results of Diffraction from Single Crystals of Trypsin Near the K-Absorption Edge of Sulfur.

Anomalous dispersion of X-ray diffraction at wavelengths near the X-ray K-absorption edge of sulfur at wavelengths around 5 A has been applied to single crystals of trypsin obtained from an ammonium sulfate solution. The multiwavelength anomalous-dispersion method based on 775 unique reflections (+183 Bijvoet mates) measured at three wavelengths near the K-absorption edge of sulfur in trypsin (two methionines and disulfide bridges of six cystines) reproduces the known features of the trypsin structure of a resolution of 4 A. It appears that there is anisotropic anomalous scattering from the disulfide bridges of cystine. The multiwavelength anomalous solvent contrast shows up at wavelengths near the K-absorption edge of the sulfate ions, which is shifted by 10 eV to higher energies with respect to that of sulfur in trypsin. The influence of the complex contrast of trypsin in 2.5 M ammonium sulfate on the dispersion of a low-order reflection is analyzed. The measurement of anomalous dispersion of X-ray diffraction at long wavelengths beyond 5 A requires a special diffractometer, the features of which are presented. An outstanding one is a detector system consisting of four multiwire proportional counters. Its efficiency is compared with that of imaging plates. The influence of radiation damage with soft X-ray diffraction from single crystals of trypsin is presented and possible remedies are discussed.

Anomalous Dispersion with Edges in the Soft X-ray Region: First Results of Diffraction from Single Crystals of Ribosomes Near the K-Absorption Edge of Phosphorus.

X-ray diffraction from a single crystal of the small ribosomal subunit of Thermus thermophilus was measured at five wavelengths near the K-absorption edge of phosphorus. The intensity of the low-order diffraction peaks varies strongly with the wavelength. It is influenced by the dispersion of contrast due to the P atoms of the ribosomal ribonucleic acid and by that of absorption, in comparable amounts.