Enhancing physical activity and reducing symptoms of patients with osteoarthritis of the knee: a randomized controlled trial of the PrevOP-Psychological Adherence Program.

BACKGROUND: This primary analysis evaluated the "PREVenting the impairment of primary Osteoarthritis by high-impact long-term Physical exercise regimen-Psychological Adherence Program" (PrevOP-PAP), designed to support patients with osteoarthritis of the knee (OAK) to engage in regular moderate-to-vigorous physical activity (MVPA) to reduce OAK symptoms (WOMAC scores). Theory-based on the health action process approach (HAPA), the intervention targeted volitional precursors of MVPA change: action and coping planning, maintenance and recovery self-efficacy, action control, and social network formation. We hypothesized that compared to an active control condition, increases in MVPA at the end of the 12-month intervention would translate into lower WOMAC scores at 24 months in the intervention condition. METHODS: Participants with radiographically verified moderate OAK (N = 241; 62.66% female; M(SD) = 65.60(7.61) years) were randomly assigned to the intervention (51%) or the active control condition. WOMAC scores (24 months) were the primary -, accelerometer-assessed MVPA (12 months) the key secondary outcomes. The PrevOP-PAP was a 12-month intervention with computer-assisted face-to-face and phone-based sessions designed to increase HAPA-proposed volitional precursors of MVPA change (up to 24 months; secondary outcomes). Intent-to-treat analyses included multiple regression and manifest path models. RESULTS: MVPA (12 months) did not mediate effects of the PrevOP-PAP on WOMAC scores (24 months). Compared to the active control condition, WOMAC scores (24 months) were lower in the intervention condition, but this effect did not remain stable in sensitivity analyses (b(SE) = -8.41(4.66), 95%-CI [-17.53; 0.71]). However, exploratory analyses revealed significantly stronger reductions in WOMAC-pain (24 months) in the intervention condition (b(SE) = -2.99(1.18), 95%-CI [-5.36; -0.63]). Groups did not differ in MVPA at 12 months (b(SE) = -3.78(3.42), 95%-CI [-10.80; 2.58]). Of the proposed precursors of MVPA change, action planning was higher in the intervention than in the control condition (24 months; b(SE) = 0.64(0.26), 95%-CI [0.14; 1.15]). CONCLUSIONS: Compared to an active control condition, the PrevOP-PAP did not produce reliable effects on WOMAC scores and none on preceding MVPA. Of the HAPA-proposed volitional precursors, only action planning was sustainably increased. Future interventions should use m-health applications to digitally support long-term changes in proposed volitional precursors of MVPA change. TRIAL REGISTRATION: German Clinical Trials Register; https://drks.de/search/de/trial/DRKS00009677 ; also available at http://apps.who.int/trialsearch/ ; registration number: DRKS00009677; date of registration: 26/01/2016.

Balance Performance across the Lifespan Assessed by the Leonardo Mechanograph®: A Cross-Sectional Study.

Reference values of sway parameters have not been published for the Leonardo mechanograph® so far. The aim of this cross-sectional study was to determine normative values on postural control measured by the force plate Leonardo Mechanograph® and to analyze the influence of age and sex on balance performance. A set of standardized standing positions with eyes opened (Romberg, semi-tandem, tandem, unipedal standing) was carried out. Analysis of covariance (ANCOVA) was used to detect age-and sex-related differences in center of pressure (COP) parameters (path length, velocity, elliptical area, anterior-posterior, and medio-lateral directions). Measurements were available for 570 subjects aged 20-86 years. Statistical analysis showed a high effect of age group on postural control (partial n² between 0.1 and 0.4) with a U-shaped dependency between postural control and age for all area- and path-related COP parameters, with the largest sway in the youngest (aged 20-40) and the oldest age group (aged 60-86). For velocity of COP, a linear deterioration with increasing age was found. Medio-lateral components of COP are likely to indicate the extent of postural control. Significant sex differences were not clearly supported by current findings. Age- and sex-related normative values are a useful resource for diagnostic, research, and training.

Greater association of peak neuromuscular performance with cortical bone geometry, bone mass and bone strength than bone density: A study in 417 older women.

BACKGROUND: We evaluated which aspects of neuromuscular performance are associated with bone mass, density, strength and geometry. METHODS: 417 women aged 60-94years were examined. Countermovement jump, sit-to-stand test, grip strength, forearm and calf muscle cross-sectional area, areal bone mineral content and density (aBMC and aBMD) at the hip and lumbar spine via dual X-ray absorptiometry, and measures of volumetric vBMC and vBMD, bone geometry and section modulus at 4% and 66% of radius length and 4%, 38% and 66% of tibia length via peripheral quantitative computed tomography were performed. The first principal component of the neuromuscular variables was calculated to generate a summary neuromuscular variable. Percentage of total variance in bone parameters explained by the neuromuscular parameters was calculated. Step-wise regression was also performed. RESULTS: At all pQCT bone sites (radius, ulna, tibia, fibula), a greater percentage of total variance in measures of bone mass, cortical geometry and/or bone strength was explained by peak neuromuscular performance than for vBMD. Sit-to-stand performance did not relate strongly to bone parameters. No obvious differential in the explanatory power of neuromuscular performance was seen for DXA aBMC versus aBMD. In step-wise regression, bone mass, cortical morphology, and/or strength remained significant in relation to the first principal component of the neuromuscular variables. In no case was vBMD positively related to neuromuscular performance in the final step-wise regression models. CONCLUSION: Peak neuromuscular performance has a stronger relationship with leg and forearm bone mass and cortical geometry as well as proximal forearm section modulus than with vBMD.

Impact of oral ibandronate 150 mg once monthly on bone structure and density in post-menopausal osteoporosis or osteopenia derived from in vivo µCT.

The effect of ibandronate 150 mg/once monthly in the treatment of post-menopausal osteopenia and osteoporosis on bone micro-structure at the distal tibia and radius has not been considered to date. Seventy post-menopausal women with osteoporosis or osteopenia were recruited. All subjects received calcium and vitamin D supplementation and were randomized to either a group which took 150 mg ibandronate oral monthly or a placebo group over a 12-month period. µCT measures of the distal tibia and radius were conducted every three months, with DXA lumbar spine and hip measurements conducted only pre and post and serum markers of bone formation and resorption measured every 6 months. After 12-months no significant impact of ibandronate on the primary outcome measures bone-volume to tissue-volume and trabecular separation at the distal tibia (p≥0.15) was found. Further multiple regression analyses of the primary end-points indicated a significant effect favoring the ibandronate intervention (p=0.045). Analysis of secondary end-points showed greater increases in distal tibia cortical thickness, cortical density and total density (p≤0.043) with ibandronate and no significant effects at the distal radius, but greater increases of hip DXA-BMD and lumbar spine DXA-BMD (p≤0.017). Ibandronate use resulted in a marked reduction in bone turnover (p<0.001). While ibandronate resulted in greater mineralization of bone, this effect differed from one body region to another. There was some impact of ibandronate on bone structure (cortical thickness) at the distal tibia, but not on bone-volume to tissue-volume or trabecular separation.