Mobility of Elderly Patients When Using the "l'Ergonome" Mobility Device

Inclusion Criteria: * The patient must have given his/her informed and signed consent * The patient must be insured or beneficiary of a health insurance plan * The patient must be in stable medical condition (no complications for the last 10 days) * The patient is incapable of changing from a laying position to a sitting position by his/herself in \<10 secondes, and requires help for such movement * The patient has a sitting-balance score \> 2/4 (Brun et al 1991: Actual Rééduc Réadaptat: (16):412-7)) Exclusion Criteria: * The patient is in an exclusion period determined by a previous study * The patient is under judicial protection, under tutorship or curatorship * The patient refuses to sign the consent * It is impossible to correctly inform the patient * The patient has fractured vertebrae or pelvis * The patient has a weak heart * The patient has joint pain localized to the dorso-lumbar region * The patient has behavioral disorders (opposition, agitation, dementia) * The patient has a medical prescription for physical restraint by bed rails. * The patient is incapable of understanding the utility of the proposed technical aide, and using it for rolling and sitting up (notion of compliance).