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The trochanteric soft tissue attenuates impact force or absorbs impact energy during a fall on the hip (thereby helps to reduce a risk of hip fracture). While the benefits should be affected by contractions of muscles spanning the hip joint, no information is available to date. We examined how the stiffness (force attenuation capacity) and energy absorption of the trochanteric soft tissue were affected by hip muscle activation during a fall. Thirteen healthy young individuals (5 males, 8 females) participated in the pelvis release experiment. Falling trials were acquired with three muscle contraction conditions: 0–20% ("relaxed"), 20–50% ("moderate"), and 60–100% ("maximal") of the maximal voluntary isometric contraction of the gluteus medius muscle. During trials, we measured real-time force and deformation behaviour of the trochanteric soft tissue. Outcome variables included the stiffness and energy absorption of the soft tissue. The stiffness and energy absorption ranged from 56.1 to 446.9 kN/m, and from 0.15 to 2.26 J, respectively. The stiffness value increased with muscle contraction, and 59% greater in "maximal" than "relaxed" condition (232.2 (SD = 121.4) versus 146.1 (SD = 49.9)). However, energy absorption decreased with muscle contraction, and 58.9% greater in "relaxed" than "maximal" condition (0.89 (SD = 0.63) versus 0.56 (SD = 0.41)). Our results provide insights on biomechanics of the trochanteric soft tissue ("natural" padding device) during impact stage of a fall, suggesting that soft tissues' protective benefits are largely affected by the level of muscle contraction. • Trochanteric soft tissue plays a role in decreasing the impact force and energy delivered to the proximal femur at impact. • The performance of the trochanteric soft tissue changes with a level of hip muscle activation during sideways falls. • Hip muscle activation increases the stiffness of trochanteric soft tissue, but decreases energy absorption. [ABSTRACT FROM AUTHOR]

Abstract: Background: We determined any difference in oesophageal function between reflux patients with and without erosive esophagitis by the application of concurrent manometry and impedance. Methods: Twenty patients with erosive esophagitis, 20 patients with non-erosive reflux disease, and 15 controls were included in this study. All subjects underwent studies with a catheter containing four impedance-measuring segments and five solid-state pressure transducers. Each subject received 10 liquid and 10 viscous boluses to be swallowed. Results: Healthy controls had greater distal oesophageal peristaltic amplitude than both patient groups (p <0.05). Normal oesophageal peristalsis was found more frequently in healthy controls than either of the patient groups (p <0.05). Patients with erosive esophagitis exhibited a lower percentage of complete bolus transit compared to healthy controls and non-erosive reflux disease patients (both p <0.05). Patients with erosive esophagitis had a longer total bolus transit time compared to healthy controls and non-erosive reflux disease patients (both p <0.05). Conclusions: Erosive esophagitis is characterized by longer oesophageal bolus transit and fewer complete bolus transit than non-erosive reflux disease. The noted differences in oesophageal bolus transit may reflect a continuum of dysfunction secondary to increasing oesophageal mucosal damage. [Copyright &y& Elsevier]