Qigong versus exercise therapy for chronic low back pain in adults--a randomized controlled non-inferiority trial.

BACKGROUND: The value of qigong in the treatment of chronic low back pain is unclear. In a randomized controlled trial, we evaluated whether qigong is non-inferior to exercise therapy in patients with chronic low back pain. METHODS: German outpatients (aged 46.7 ± 10.4) with chronic low back pain [mean visual analogue scale (VAS), 53.9 ± 12.5 mm] were enrolled and randomly allocated in a 1:1 ratio to receive either qigong (64 patients, 12 sessions with 1 × 90 min/week over 3 months) or exercise therapy (63 patients, 12 sessions 1 × 60 min/week). The primary outcome measure was the average pain intensity over the last 7 days on a VAS (0-100 mm, 0 = no pain, 100 = worst imaginable pain, non-inferiority margin = 5 mm) after 3 months. Follow-up was measured after 6 and 12 months. RESULTS: The mean adjusted low back pain intensity after 3 months was 34.8 mm [95% confidence interval (CI) 29.5; 40.2] in the qigong group and 33.1 mm (95% CI 27.7; 38.4) in the exercise group. Non-inferiority of the qigong group compared with the exercise group failed to show statistical significance (p = 0.204). In both groups, 10 patients reported suspected adverse reactions (e.g., muscle soreness, dizziness, pain) the total number was comparable in both groups (qigong n = 40, exercise n = 44). CONCLUSIONS: Qigong was not proven to be non-inferior to exercise therapy in the treatment of chronic low back pain. Its role in the prevention of chronic low back pain might be addressed in further studies.

Measurement of the hyperelastic properties of ex vivo brain tissue slices.

The elastic and hyperelastic properties of brain tissue are of interest to the medical research community as there are several applications where accurate characterization of these properties is crucial for an accurate outcome. The linear response is applicable to brain elastography, while the non-linear response is of interest for surgical simulation programs. Because of the biological differences between gray and white matter, it is reasonable to expect a difference in their mechanical properties. The goal of this work is to characterize the elastic and hyperelastic properties of the brain gray and white matter. In this method, force-displacement data of these tissues were acquired from 25 different brain samples using an indentation apparatus. These data were processed with an inverse problem algorithm using finite element method as the forward problem solver. Young's modulus and the hyperelastic parameters corresponding to the commonly used Polynomial, Yeoh, Arruda-Boyce, and Ogden models were obtained. The parameters characterizing the linear and non-linear mechanical behavior of gray and white matters were found to be significantly different. Young's modulus was 1787±186 and 1195±157Pa for white matter and gray matter, respectively. Among hyperelastic models, due to its accuracy, fewer parameters and shorter computational time requirements, Yeoh model was found to be the most suitable. Due to the significant differences between the linear and non-linear tissue response, we conclude that incorporating these differences into brain biomechanical models is necessary to increase accuracy.