bone metabolism and quality
Conditions
Interventions
Prior to the bed rest phase, subjects will be randomly assigned to one of three
experimental groups (n=8 in each group).
* Group 1: 6° HDBR with no centrifugation (passive control).
* Group 2: 6° H
Sponsors
Department of muscle and bone metabolism
Eligibility
Age
18 Years to 99 Years
Inclusion criteria
Inclusion criteria: * Physically and mentally healthy test subjects that are able and declare their willingness to participate in the entire study and successfully passed the psychological and medical screening * Aged between 24 and 55 years old with a Body Mass Index (BMI) of 19 - 30 kg/m2, height between 153 -190 cm * Non-smoker, for at least six months before the start of the study * Capable of completing the study * Willing to stay in bed with or without weight-bearing (artificial gravity) for 60 days * Demonstrable medical insurance and official certificate of absence of criminal record * Demonstrable dentist certificate
Exclusion criteria
Exclusion criteria: Drug, medication or alcohol abuse (regular consumption of more than 20-30 g alcohol/day) * A requirement for any prescription medications * Vegetarian, vegan (during the study) * Migraine, chronic headache * Insomnia or other sleep disorders * Previous psychiatric illness * Claustrophobia * Increased intraocular pressure * Any eye disorder that could significantly impact or jeopardize visual function * Hyperopia > +5.0 Diopters * Myopia > - 6 Diopters * Astigmatism > 3 Diopters * History of laser surgery, glaucoma and retinal surgery * Hiatus hernia * Gastro-oesophageal reflux * Gastrointestinal stenosis, dysphagia * Current or history of chronic bowel disease * Diabetes mellitus * Rheumatic illness * Current or a history of (chronic) pulmonary disease * Current muscle or joint disease or disorder * History of prolapsed intervertebral disc * Chronic back complaints * Bone fractures less than 1 year prior to study * Kidney disorder: deviations from normal values for creatinine in plasma. Deviations from normal values (Normal values for creatinine in plasma 30 dB, or implanted hearing de
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| One Primary objective is to assess changes in volumetric bone mineral density of the trabecular and cortical compartment as well as bone strength by means of finite element modelling (failure load, stiffness, cortical stress, trabecular stress) of the proximal femur as a weight bearing skeletal region by means of QCT measurements of the hip. Endpoint 1: changes in total bone mineral density [g/cm3] in the proximal femur (QCT) Endpoint 2: changes in total bone mineral density [g/cm3] in the femoral neck (QCT) Endpoint 3: changes in trabecular bone mineral density [g/cm3] in the proximal femur (QCT) Endpoint 4: changes in trabecular bone mineral density [g/cm3] in the femoral neck (QCT) Endpoint 5: changes in cortical bone mineral density [g/cm3] in the proximal femur (QCT) Endpoint 6: changes in cortical bone mineral density [g/cm3] in the femoral neck (QCT) Endpoint 7: changes in bone strengths by means of Finite Element Analysis in the total proximal femur and femoral neck (QCT) Another primary objective is to assess the changes of trabecular and cortical microstructure as well as bone strength by means of finite element modelling by means HR-pQCT measurements of the tibia and radius. Endpoint 8: changes in total, trabecular and cortical bone density [mg/cm³] at the tibia and radius (HR-pQCT). Endpoint 9: changes in cortical thickness [µm], area [mm] and porosity at the tibia and radius (HR-pQCT). Endpoint 10: changes in bone microstructural parameter like trabecular number [mm-1], trabecular thickness [µm], trabecular bone separation [µm] at the tibia and radius | — |
Secondary
| Measure | Time frame |
|---|---|
| We would like to refer to the complete research protocol for all other research variables / outcome measures of the planned study. | — |
Countries
Netherlands
Outcome results
None listed