No abstract

Although the addition of whole-body vibration to squat training failed to result in a significant improvement in functional performance and self-reported status of knee osteoarthritis in the elderly, the intragroup results suggest that whole-body vibration may represent a feasible and effective way of improving the functionality and self-perception of disease status in older adults with knee OA.

Background : Osteoarthritis of the knee (kOA) is a chronic, progressive, degenerative health condition that contributes to the imbalance between the synthesis and destruction of articular cartilage. Recently, whole body vibration (WBV) training has been recommended as an effective alternative for strength training in elderly people, and various physiological effects are obtained in response to exercise performed on a vibratory platform, such as an increase in muscle activation and improved muscle performance. However, the effects of WBV particularly on the strength of the quadriceps muscle and neuronal plasticity are unknown. Objective : The aim of this study was to evaluate the effects of adding WBV to squat training on the isometric quadriceps muscle strength (IQMS) and the plasma levels of brain-derived neurotrophic factor (BDNF) in elderly woman with kOA. Methods : Fifteen elderly women ≥65 years of age with kOA were randomized into two interventions: (1) the vibration group (VG), in which participants performed squat exercise training in association with WBV or (2) the exercise group (EG), in which participants performed squat exercise training without vibration, for 12 weeks 3×/week. Results : Compared to the EG group, the VG group demonstrated a significantly greater delta (Δ) in IQMS values (IC95% 0.43–7.06; p ≤ 0.05) and in Δ BDNF plasma levels (IC95% −32.51 to 4.217; p ≤ 0.05) after the intervention period. There was an association between increase of Δ BDNF plasma levels and increase of Δ IQMS ( β = 0.57; R 2 = 0.32; p = 0.03). Conclusion : The addition of WBV to squat exercise training improves lower limb muscle performance in elderly women with kOA. These findings suggest that the improvement in muscle performance is related to neuromuscular adaptations induced by WBV. Clinical Trial Registration : www.ClinicalTrials.gov , identifier NCT03918291.

The aim of this study was to analyze the levels of brain-derived neurotrophic factor (BDNF) in both the plasma and synovial fluid of patients with primary knee osteoarthritis compared with control individuals and to investigate the relationship between BDNF levels and self-reported pain. Twenty-seven patients with knee osteoarthritis (OA) and 19 healthy subjects were enrolled in the study. Anteroposterior knee radiographs were taken to determine the disease severity of the affected knee. Radiographic grading of OA in the knee was performed using the Kellgren-Lawrence criteria. The BDNF levels in the plasma and synovial fluid were measured by enzyme-linked immunosorbent assay. The mean plasma BDNF levels of the knee OA patients were significantly higher than that of the healthy controls (2,378 ± 1,067.2 vs. 1,756 ± 804.3 pg/mL, p < 0.05). BDNF levels in the synovial fluid of OA patients (358.9 ± 178.4 pg/mL) were sixfold lower than in corresponding blood samples (p < 0.0001) and fourfold lower than in the plasma of healthy controls (p < 0.0001). Subsequent analyses showed that the plasma BDNF levels significantly correlated with self-reported pain (Western Ontario and McMaster Universities Osteoarthritis Index) (r s = 0.39, p = 0.04). Furthermore, no correlation was found between the plasma and synovial fluid BDNF concentrations and knee OA severity. The findings of this study suggest that systemic BDNF levels are most likely associated with the mechanism of joint pain in knee OA in the acute stage of joint inflammatory process. Further studies are necessary to address the functional role of BDNF in the modulation of pain to establish new therapeutic implications.